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1.  Programmatic assessment of competency-based workplace learning: when theory meets practice 
BMC Medical Education  2013;13:123.
In competency-based medical education emphasis has shifted towards outcomes, capabilities, and learner-centeredness. Together with a focus on sustained evidence of professional competence this calls for new methods of teaching and assessment. Recently, medical educators advocated the use of a holistic, programmatic approach towards assessment. Besides maximum facilitation of learning it should improve the validity and reliability of measurements and documentation of competence development. We explored how, in a competency-based curriculum, current theories on programmatic assessment interacted with educational practice.
In a development study including evaluation, we investigated the implementation of a theory-based programme of assessment. Between April 2011 and May 2012 quantitative evaluation data were collected and used to guide group interviews that explored the experiences of students and clinical supervisors with the assessment programme. We coded the transcripts and emerging topics were organised into a list of lessons learned.
The programme mainly focuses on the integration of learning and assessment by motivating and supporting students to seek and accumulate feedback. The assessment instruments were aligned to cover predefined competencies to enable aggregation of information in a structured and meaningful way. Assessments that were designed as formative learning experiences were increasingly perceived as summative by students. Peer feedback was experienced as a valuable method for formative feedback. Social interaction and external guidance seemed to be of crucial importance to scaffold self-directed learning. Aggregating data from individual assessments into a holistic portfolio judgement required expertise and extensive training and supervision of judges.
A programme of assessment with low-stakes assessments providing simultaneously formative feedback and input for summative decisions proved not easy to implement. Careful preparation and guidance of the implementation process was crucial. Assessment for learning requires meaningful feedback with each assessment. Special attention should be paid to the quality of feedback at individual assessment moments. Comprehensive attention for faculty development and training for students is essential for the successful implementation of an assessment programme.
PMCID: PMC3851012  PMID: 24020944
Programmatic assessment; Workplace learning; Undergraduate (veterinary) medical education; (Peer) Feedback; Mentoring; Personal development
2.  Outcome errors are not necessary for learning orthopedic bone drilling 
Canadian Journal of Surgery  2009;52(2):98-102.
When learning orthopedic bone drilling, a surgical trainee relies on internally generated and externally provided feedback. The quality and type of feedback often varies in the clinical environment, thus affecting skill acquisition. We investigated the effect of feedback on technical error (plunging) when novice surgical trainees learned bone drilling.
Medical students (n = 22) and experienced postgraduate surgical residents (n = 4) drilled bicortical holes in a lamb femur under 1 of 3 feedback conditions: no feedback, self-generated feedback and externally generated feedback. Novices performed a retention test (10 bicortical holes) 1 week after the initial training. We measured plunge depth, the clinically relevant outcome, using computer-assisted methods.
During the initial experiment, the plunges of novices who were exposed to external feedback were similar to those of residents in the experienced group. Novices in the self-generated feedback group plunged more than those in the external feedback group or those in the experienced group (p = 0.002). All novices plunged similarly on the retention test, a measure of true skill learning.
When learning bicortical bone drilling, feedback related to plunging is not necessary to achieve a competent level of performance. In addition, although external feedback facilitates the achievement of better outcomes, it does not improve learning. It is suggested that to minimize plunging, trainees should learn how to optimize their drilling through the bone rather than how to prevent the plunge.
PMCID: PMC2663499  PMID: 19399203
3.  Vertically integrated shared learning models in general practice: a qualitative study 
BMC Family Practice  2013;14:144.
The numbers of learners seeking placements in general practice is rapidly increasing as an ageing workforce impacts on General Practitioner availability. The traditional master apprentice model that involves one-to-one teaching is therefore leading to supervision capacity constraints. Vertically integrated (VI) models may provide a solution. Shared learning, in which multiple levels of learners are taught together in the same session, is one such model. This study explored stakeholders’ perceptions of shared learning in general practices in northern NSW, Australia.
A qualitative research method, involving individual semi-structured interviews with GP supervisors, GP registrars, Prevocational General Practice Placements Program trainees, medical students and practice managers situated in nine teaching practices, was used to investigate perceptions of shared learning practices. A thematic analysis was conducted on 33 transcripts by three researchers.
Participants perceived many benefits to shared learning including improved collegiality, morale, financial rewards, and better sharing of resources, knowledge and experience. Additional benefits included reduced social and professional isolation, and workload. Perceived risks of shared learning included failure to meet the individual needs of all learners. Shared learning models were considered unsuitable when learners need to: receive remediation, address a specific deficit or immediate learning needs, learn communication or procedural skills, be given personalised feedback or be observed by their supervisor during consultations. Learners’ acceptance of shared learning appeared partially dependent on their supervisors’ small group teaching and facilitation skills.
Shared learning models may partly address supervision capacity constraints in general practice, and bring multiple benefits to the teaching environment that are lacking in the one-to-one model. However, the risks need to be managed appropriately, to ensure learning needs are met for all levels of learners. Supervisors also need to consider that one-to-one teaching may be more suitable in some instances. Policy makers, medical educators and GP training providers need to ensure that quality learning outcomes are achieved for all levels of learners. A mixture of one-to-one and shared learning would address the benefits and downsides of each model thereby maximising learners’ learning outcomes and experiences.
PMCID: PMC3851562  PMID: 24079420
Registrars; Prevocational trainees; Medical students; Medical education; Vertical integration; Near-peer teaching; General practice; Postgraduate training
4.  A cluster randomized controlled trial to evaluate the effectiveness of the clinically integrated RHL evidence -based medicine course 
Background and objectives
Evidence-based health care requires clinicians to engage with use of evidence in decision-making at the workplace. A learner-centred, problem-based course that integrates e-learning in the clinical setting has been developed for application in obstetrics and gynaecology units. The course content uses the WHO reproductive health library (RHL) as the resource for systematic reviews. This project aims to evaluate a clinically integrated teaching programme for incorporation of evidence provided through the WHO RHL. The hypothesis is that the RHL-EBM (clinically integrated e-learning) course will improve participants' knowledge, skills and attitudes, as well as institutional practice and educational environment, as compared to the use of standard postgraduate educational resources for EBM teaching that are not clinically integrated.
The study will be a multicentre, cluster randomized controlled trial, carried out in seven countries (Argentina, Brazil, Democratic Republic of Congo, India, Philippines, South Africa, Thailand), involving 50-60 obstetrics and gynaecology teaching units. The trial will be carried out on postgraduate trainees in the first two years of their training. In the intervention group, trainees will receive the RHL-EBM course. The course consists of five modules, each comprising self-directed e-learning components and clinically related activities, assignments and assessments, coordinated between the facilitator and the postgraduate trainee. The course will take about 12 weeks, with assessments taking place pre-course and 4 weeks post-course. In the control group, trainees will receive electronic, self-directed EBM-teaching materials. All data collection will be online.
The primary outcome measures are gain in EBM knowledge, change in attitudes towards EBM and competencies in EBM measured by multiple choice questions (MCQs) and a skills-assessing questionniare administered eletronically. These questions have been developed by using questions from validated questionnaires and adapting them to the current course. Secondary outcome measure will be educational environment towards EBM which will be assessed by a specifically developed questionnaire.
Expected outcomes
The trial will determine whether the RHL EBM (clinically integrated e-leraning) course will increase knowledge, skills and attitudes towards EBM and improve the educational environment as compared to standard teaching that is not clinically integrated. If effective, the RHL-EBM course can be implemented in teaching institutions worldwide in both, low-and middle income countries as well as industrialized settings. The results will have a broader impact than just EBM training because if the approach is successful then the same educational strategy can be used to target other priority clinical and methodological areas.
Trial Registration
PMCID: PMC2880979  PMID: 20470382
5.  An exploratory study into the impact and acceptability of formatively used progress testing in postgraduate obstetrics and gynaecology 
Part of recent reforms of postgraduate medical training in the Netherlands is the introduction of formatively intended knowledge testing or progress testing. We previously evaluated the construct validity and reliability of postgraduate progress testing. However, when assessment is intended to be formative, the acceptability of the test (scores) and the educational impact that is achieved are at least as important in the utility of this assessment format. We developed a questionnaire targeted at both educational supervisors and postgraduate trainees, containing questions on general acceptability, educational impact and acceptability of test content. 90 % of trainees and 84 % of educational supervisors completed the questionnaire. The general acceptability of formatively used progress testing is good; however, the self-reported educational impact is limited. Furthermore, trainees query the validity of test content. Formatively intended progress testing is well accepted; however the impact is limited. We discuss the importance of feedback quality and the effect of grading. Furthermore we start a debate on whether, for a genuine effect on learning, formative assessment should have consequences, either by entwining the assessment with the training programme or by linking the assessment to a summative standard.
PMCID: PMC3722371
Postgraduate; Formative assessment; Progress test; Acceptability; Educational impact
6.  An exploratory study into the impact and acceptability of formatively used progress testing in postgraduate obstetrics and gynaecology 
Part of recent reforms of postgraduate medical training in the Netherlands is the introduction of formatively intended knowledge testing or progress testing. We previously evaluated the construct validity and reliability of postgraduate progress testing. However, when assessment is intended to be formative, the acceptability of the test (scores) and the educational impact that is achieved are at least as important in the utility of this assessment format. We developed a questionnaire targeted at both educational supervisors and postgraduate trainees, containing questions on general acceptability, educational impact and acceptability of test content. 90 % of trainees and 84 % of educational supervisors completed the questionnaire. The general acceptability of formatively used progress testing is good; however, the self-reported educational impact is limited. Furthermore, trainees query the validity of test content. Formatively intended progress testing is well accepted; however the impact is limited. We discuss the importance of feedback quality and the effect of grading. Furthermore we start a debate on whether, for a genuine effect on learning, formative assessment should have consequences, either by entwining the assessment with the training programme or by linking the assessment to a summative standard.
PMCID: PMC3722371
Postgraduate; Formative assessment; Progress test; Acceptability; Educational impact
7.  The national portfolio for postgraduate family medicine training in South Africa: a descriptive study of acceptability, educational impact, and usefulness for assessment 
BMC Medical Education  2013;13:101.
Since 2007 a portfolio of learning has become a requirement for assessment of postgraduate family medicine training by the Colleges of Medicine of South Africa. A uniform portfolio of learning has been developed and content validity established among the eight postgraduate programmes. The aim of this study was to investigate the portfolio’s acceptability, educational impact, and perceived usefulness for assessment of competence.
Two structured questionnaires of 35 closed and open-ended questions were delivered to 53 family physician supervisors and 48 registrars who had used the portfolio. Categorical and nominal/ordinal data were analysed using simple descriptive statistics. The open-ended questions were analysed with ATLAS.ti software.
Half of registrars did not find the portfolio clear, practical or feasible. Workshops on portfolio use, learning, and supervision were supported, and brief dedicated time daily for reflection and writing. Most supervisors felt the portfolio reflected an accurate picture of learning, but just over half of registrars agreed. While the portfolio helped with reflection on learning, participants were less convinced about how it helped them plan further learning. Supervisors graded most rotations, suggesting understanding the summative aspect, while only 61% of registrars reflected on rotations, suggesting the formative aspects are not yet optimally utilised. Poor feedback, the need for protected academic time, and pressure of service delivery impacting negatively on learning.
This first introduction of a national portfolio for postgraduate training in family medicine in South Africa faces challenges similar to those in other countries. Acceptability of the portfolio relates to a clear purpose and guide, flexible format with tools available in the workplace, and appreciating the changing educational environment from university-based to national assessments. The role of the supervisor in direct observations of the registrar and dedicated educational meetings, giving feedback and support, cannot be overemphasized.
PMCID: PMC3733709  PMID: 23885806
8.  Postgraduate trainees as simulated patients in psychiatric training: Role players and interviewers perceptions 
Indian Journal of Psychiatry  2010;52(4):350-354.
Teaching skills to enhance competence in clinical settings need to have a focus on learning how to do. This paper describes the subjective experiences and feedback of trainees who participated in a teaching technique using postgraduate trainees as simulated patients.
Materials and Methods
The Objective Structured Clinical Assessment and Feedback was employed for training using trainees as simulated patients and interviewers. This exercise is performed in front of consultants and peers who subsequently provide feedback about the content and process using a structured format. In order to assess the subjective experience of the interviewer and the role players they were requested to provide structured feedback on several aspects. The trainee role player provided feedback on comfort in playing the role, need for further inputs, satisfaction regarding role play, satisfaction with the interview, and the overall effect of the activity. The trainee interviewer gave feedback on his/her level of comfort performing in front of a peer group, being watched, and evaluated in a group.
The feedback forms from 15 sessions were analyzed. Only two of the role players indicated that they felt very uncomfortable while the rest reported comfort. Twelve of the 15 trainees who simulated patients felt they needed more inputs to improve the clarity of the role play; however they all reported feeling satisfied with the role play or interview. The feedback from the interviewers indicated that most were comfortable in all aspects, i.e. conducting the interview, performing in front of a group, being evaluated, and given feedback in front of a group.
The trainees report indicates that those simulating patients need more clarity on their roles and majority had no discomfort performing in front of a group. Interviewers were satisfied and comfortable with all aspects. On the whole, simulated interviews and role plays were found to be an acceptable teaching method by postgraduate psychiatry trainees.
PMCID: PMC3025162  PMID: 21267370
Postgraduate training; psychiatry; role plays; simulated patients
9.  Comprehensive feedback on trainee surgeons’ non-technical skills 
This study aimed to explore the content of conversations, feedback style, and perceived usefulness of feedback to trainee surgeons when conversations were stimulated by a tool for assessing surgeons’ non-technical skills.
Trainee surgeons and their supervisors used the Non-Technical Skills for Surgeons in Denmark tool to stimulate feedback conversations. Audio recordings of post-operation feedback conversations were collected. Trainees and supervisors provided questionnaire responses on the usefulness and comprehensiveness of the feedback. The feedback conversations were qualitatively analyzed for content and feedback style. Usefulness was investigated using a scale from 1 to 5 and written comments were qualitatively analyzed.
Six trainees and six supervisors participated in eight feedback conversations. Eighty questionnaires (response rate 83 percent) were collected from 13 trainees and 12 supervisors. Conversations lasted median eight (2-15) minutes. Supervisors used the elements and categories in the tool to structure the content of the conversations. Supervisors tended to talk about the trainees’ actions and their own frames rather than attempting to understand the trainees’ perceptions. Supervisors and trainees welcomed the feedback opportunity and agreed that the conversations were useful and comprehensive.
The content of the feedback conversations reflected the contents of the tool and the feedback was considered useful and comprehensive. However, supervisors talked primarily about their own frames, so in order for the feedback to reach its full potential, supervisors may benefit from training techniques to stimulate a deeper reflection among trainees.
PMCID: PMC4306652  PMID: 25602262
feedback; surgery; communication; decision making; leadership
10.  Quantitative analysis of regulatory flexibility under changing environmental conditions 
Day length changes with the seasons in temperate latitudes, affecting the many biological rhythms that entrain to the day/night cycle: we measure these effects on the expression of Arabidopsis clock genes, using RNA and reporter gene readouts, with a new method of phase analysis.Dusk sensitivity is proposed as a simple, natural and general mathematical measure to analyse and manipulate the changing phase of a clock output relative to the change in the day/night cycle.Dusk sensitivity shows how increasing the numbers of feedback loops in the Arabidopsis clock models allows more flexible regulation, consistent with a previously-proposed, general operating principle of biological networks.The Arabidopsis clock genes show flexibility of regulation that is characteristic of a three-loop clock model, validating aspects of the model and the operating principle, but some clock output genes show greater flexibility arising from direct light regulation.
The analysis of dynamic, non-linear regulation with the aid of mechanistic models is central to Systems Biology. This study compares the predictions of mechanistic, mathematical models of the circadian clock with molecular time-series data on rhythmic gene expression in the higher plant Arabidopsis thaliana. Analysis of the models helps us to understand (explain and predict) how the clock gene circuit balances regulation by external and endogenous factors to achieve particular behaviours. Such multi-factorial regulation is ubiquitous in, and characteristic of, living systems.
The Earth's rotation causes predictable changes in the environment, notably in the availability of sunlight for photosynthesis. Many biological processes are driven by the environmental input via sensory pathways, for example, from photoreceptors. Circadian clocks provide an alternative strategy. These endogenous, 24-h rhythms can drive biological processes that anticipate the regular environmental changes, rather than merely responding. Many rhythmic processes have both light and clock control. Indeed, the clock components themselves must balance internal timing with external inputs, because circadian clocks are reset daily through light regulation of one or more clock components. This process of entrainment is complicated by the change in day length. When the times of dawn and dusk move apart in summer, and closer together in winter, does the clock track dawn, track dusk or interpolate between them?
In plants, the clock controls leaf and petal movements, the opening and closing of stomatal pores, the discharge of floral fragrances, and many metabolic activities, especially those associated with photosynthesis. Centuries of physiological studies have shown that these rhythms can behave differently. Flowering in Ipomoea nil (Pharbitis nil, Japanese morning glory) is controlled by a rhythm that tracks the time of dusk, to give a classic example. We showed that two other rhythms associated with vegetative growth track dawn in this species (Figure 5A), so the clock system allows flexible regulation.
The relatively small number of components involved in the circadian clockwork makes it an ideal candidate for mathematical modelling. Molecular genetic studies in a variety of model eukaryotes have shown that the circadian rhythm is generated by a network of 6–20 genes. These genes form feedback loops generating a rhythm in mRNA production. A single negative feedback loop in which a gene encodes a protein that, after several hours, turns off transcription is capable of generating a circadian rhythm, in principle. A single light input can entrain the clock to ‘local time', synchronised with a light–dark cycle. However, real circadian clocks have proven to be more complicated than this, with multiple light inputs and interlocked feedback loops.
We have previously argued from mathematical analysis that multi-loop networks increase the flexibility of regulation (Rand et al, 2004) and have shown that appropriately deployed flexibility can confer functional robustness (Akman et al, 2010). Here we test whether that flexibility can be demonstrated in vivo, in the model plant, A. thaliana. The Arabidopsis clock mechanism comprises a feedback loop in which two partially redundant, myb transcription factors, LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1), repress the expression of their activator, TIMING OF CAB EXPRESSION 1 (TOC1). We previously modelled this single-loop circuit and showed that it was not capable of recreating important data (Locke et al, 2005a). An extended, two-loop model was developed to match observed behaviours, incorporating a hypothetical gene Y, for which the best identified candidate was the GIGANTEA gene (GI) (Locke et al, 2005b). Two further models incorporated the TOC1 homologues PSEUDO-RESPONSE REGULATOR (PRR) 9 and PRR7 (Locke et al, 2006; Zeilinger et al, 2006). In these circuits, a morning oscillator (LHY/CCA1–PRR9/7) is coupled to an evening oscillator (Y/GI–TOC1) via the original LHY/CCA1–TOC1 loop.
These clock models, like those for all other organisms, were developed using data from simple conditions of constant light, darkness or 12-h light–12-h dark cycles. We therefore tested how the clock genes in Arabidopsis responded to light–dark cycles with different photoperiods, from 3 h light to 18 h light per 24-h cycle (Edinburgh, 56° North latitude, has 17.5 h light in midsummer). The time-series assays of mRNA and in vivo reporter gene images showed a range of peak times for different genes, depending on the photoperiod (Figure 5C). A new data analysis method, mFourfit, was introduced to measure the peak times, in the Biological Rhythms Analysis Software Suite (BRASS v3.0). None of the genes showed the dusk-tracking behaviour characteristic of the Ipomoea flowering rhythm. The one-, two- and three-loop models were analysed to understand the observed patterns. A new mathematical measure, dusk sensitivity, was introduced to measure the change in timing of a model component versus a change in the time of dusk. The one- and two-loop models tracked dawn and dusk, respectively, under all conditions. Only the three-loop model (Figure 5B) had the flexibility required to match the photoperiod-dependent changes that we found in vivo, and in particular the unexpected, V-shaped pattern in the peak time of TOC1 expression. This pattern of regulation depends on the structure and light inputs to the model's evening oscillator, so the in vivo data supported this aspect of the model. LHY and CCA1 gene expression under short photoperiods showed greater dusk sensitivity, in the interval 2–6 h before dawn, than the three-loop model predicted, so these data will help to constrain future models.
The approach described here could act as a template for experimental biologists seeking to understand biological regulation using dynamic, experimental perturbations and time-series data. Simulation of mathematical models (despite known imperfections) can provide contrasting hypotheses that guide understanding. The system's detailed behaviour is complex, so a natural and general measure such as dusk sensitivity is helpful to focus on one property of the system. We used the measure to compare models, and to predict how this property could be manipulated. To enable additional analysis of this system, we provide the time-series data and experimental metadata online.
The circadian clock controls 24-h rhythms in many biological processes, allowing appropriate timing of biological rhythms relative to dawn and dusk. Known clock circuits include multiple, interlocked feedback loops. Theory suggested that multiple loops contribute the flexibility for molecular rhythms to track multiple phases of the external cycle. Clear dawn- and dusk-tracking rhythms illustrate the flexibility of timing in Ipomoea nil. Molecular clock components in Arabidopsis thaliana showed complex, photoperiod-dependent regulation, which was analysed by comparison with three contrasting models. A simple, quantitative measure, Dusk Sensitivity, was introduced to compare the behaviour of clock models with varying loop complexity. Evening-expressed clock genes showed photoperiod-dependent dusk sensitivity, as predicted by the three-loop model, whereas the one- and two-loop models tracked dawn and dusk, respectively. Output genes for starch degradation achieved dusk-tracking expression through light regulation, rather than a dusk-tracking rhythm. Model analysis predicted which biochemical processes could be manipulated to extend dusk tracking. Our results reveal how an operating principle of biological regulators applies specifically to the plant circadian clock.
PMCID: PMC3010117  PMID: 21045818
Arabidopsis thaliana; biological clocks; dynamical systems; gene regulatory networks; mathematical models; photoperiodism
11.  Training evaluation: a case study of training Iranian health managers 
The Ministry of Health and Medical Education in the Islamic Republic of Iran has undertaken a reform of its health system, in which-lower level managers are given new roles and responsibilities in a decentralized system. To support these efforts, a United Kingdom-based university was contracted by the World Health Organization to design a series of courses for health managers and trainers. This process was also intended to develop the capacity of the National Public Health Management Centre in Tabriz, Iran, to enable it to organize relevant short courses in health management on a continuing basis. A total of seven short training courses were implemented, three in the United Kingdom and four in Tabriz, with 35 participants. A detailed evaluation of the courses was undertaken to guide future development of the training programmes.
The Kirkpatrick framework for evaluation of training was used to measure participants' reactions, learning, application to the job, and to a lesser extent, organizational impact. Particular emphasis was put on application of learning to the participants' job. A structured questionnaire was administered to 23 participants, out of 35, between one and 13 months after they had attended the courses. Respondents, like the training course participants, were predominantly from provincial universities, with both health system and academic responsibilities. Interviews with key informants and ex-trainees provided supplemental information, especially on organizational impact.
Participants' preferred interactive methods for learning about health planning and management. They found the course content to be relevant, but with an overemphasis on theory compared to practical, locally-specific information. In terms of application of learning to their jobs, participants found specific information and skills to be most useful, such as health systems research and group work/problem solving. The least useful areas were those that dealt with training and leadership. Participants reported little difficulty in applying learning deemed "useful", and had applied it often. In general, a learning area was used less when it was found difficult to apply, with a few exceptions, such as problem-solving. Four fifths of respondents claimed they could perform their jobs better because of new skills and more in-depth understanding of health systems, and one third had been asked to train their colleagues, indicating a potential for impact on their organization. Interviews with key informants indicated that job performance of trainees had improved.
The health management training programmes in Iran, and the external university involved in capacity building, benefited from following basic principles of good training practice, which incorporated needs assessment, selection of participants and definition of appropriate learning outcomes, course content and methods, along with focused evaluation. Contracts for external assistance should include specific mention of capacity building, and allow for the collaborative development of courses and of evaluation plans, in order to build capacity of local partners throughout the training cycle. This would also help to develop training content that uses material from local health management situations to demonstrate key theories and develop locally required skills. Training evaluations should as a minimum assess participants' reactions and learning for every course. Communication of evaluation results should be designed to ensure that data informs training activities, as well as the health and human resources managers who are investing in the development of their staff.
PMCID: PMC2654422  PMID: 19265528
12.  Effect of domestic violence training 
Canadian Family Physician  2014;60(7):618-624.
To describe and evaluate the effectiveness of domestic violence education in improving physicians’ knowledge, recognition, and management of abused women.
Data sources
The Cochrane Database of Systematic Reviews, MEDLINE, PubMed, PsycINFO, ERIC, and EMBASE were searched for articles published between January 1, 2000, and November 1, 2012. This search was supplemented by manual searches for relevant articles using a combined text-word and MeSH-heading search strategy.
Study selection
Randomized controlled trials were selected that used educational interventions among physicians and provided data on the effects of the interventions.
Nine randomized controlled trials were included that described different educational approaches with various outcome measures. Three studies examined the effects of educational interventions among postgraduate trainee physicians and found an increase in knowledge but no change in behaviour with regard to identifying victims of domestic violence. Six studies examined educational interventions for practising physicians. Three of these studies used multifaceted physician training that combined education with system support interventions to change physician behaviour, such as increasing general awareness of domestic violence with brochures and posters, providing aids to remind physicians how to identify victims, facilitating physician access to victim support services, and providing audits and feedback. Multifaceted educational interventions included interactive workshops, Web-based learning, and experiential training. Another study used focus-group discussions and training, and showed improved domestic violence reporting among physicians. The remaining 2 studies showed improved perceptions of practising physicians’ self-efficacy using problem-based online learning.
It was difficult to determine the most effective educational strategy, as the educational interventions and the outcome measures varied among the selected studies. Brief interventions for postgraduate trainee physicians improved knowledge but did not seem to affect behaviour. Online education using a problem-based learning format improved practising physicians’ perceptions, knowledge, and skills in managing domestic violence. Physician training combined with system support interventions seemed to benefit domestic violence victims and increase referrals to domestic violence support resources.
PMCID: PMC4096259  PMID: 25022633
13.  Development and pretesting of an electronic learning module to train health care professionals on the use of the Pediatric Respiratory Assessment Measure to assess acute asthma severity 
Severity-specific guidelines based on the Pediatric Respiratory Assessment Measure (PRAM), a validated clinical score, reduce pediatric asthma hospitalization rates.
To develop, pretest the educational value of and revise an electronic learning module to train health care professionals on the use of the PRAM.
The respiratory efforts of 32 children with acute asthma were videotaped and pulmonary auscultation was recorded. A pilot module, composed of a tutorial and 18 clinical cases, was developed in French and English. Health care professionals completed the module and provided feedback. The performance of participants, case quality and difficulty, and learning curve were assessed using the Rasch test; quantitative and qualitative feedback served to revise the module.
Seventy-two participants (19 physicians, 22 nurses, four respiratory therapists and 27 health care trainees) with a balanced distribution across self-declared expertise (26% beginner, 35% competent and 39% expert) were included. The accuracy of experts was superior to beginners (OR 1.79, 1.15 and 2.79, respectively). Overall performance significantly improved between the first and latter half of cases (P<0.001). Participants assessed the module to be clear (96%), relevant (98%), realistic (94%) and useful (99%) to learn the PRAM. The qualitative/quantitative analysis led to the deletion of three cases, modification of remaining cases to further enhance quality and reordering within three levels of difficulty.
Using rigorous educational methods, an electronic module was developed to teach health care professionals on use of the PRAM score. Using the back-translation technique, both French and English versions were developed and validated simultaneously. The pilot module comprised a tutorial and three case-scenario sections, and was tested on a target audience of physicians, nurses, respiratory therapists and medical trainees.
The final electronic learning module met the clarity and quality requirements of a good teaching tool, with a demonstrated learning effect and high appreciation by health care professionals. Available in French and English, it is offered to facilitate implementation of PRAM-based acute pediatric asthma guidelines.
PMCID: PMC3917818  PMID: 24046819
Asthma; Child; Clinical score; Computer-assisted learning; Emergency medicine; Health personnel; Validation studies
14.  The Development of Scientific Communication Skills: A Qualitative Study of the Perceptions of Trainees and Their Mentors 
Scientific communication, both written and oral, is the cornerstone of success in biomedical research, yet formal instruction is rarely provided. Trainees with little exposure to Standard Academic English may find developing scientific communication skills challenging. In this exploratory, hypothesis-generating qualitative study, the authors examined the process by which mentored junior researchers learn scientific communication skills, their feelings about the challenges, and their mentor’s role in the process.
In 2010, the authors conducted semi-structured focus groups and interviews to explore research trainees’ and faculty mentors’ perceptions and practices regarding scientific communication skills development, as part of the development phase of a larger quantitative study. The facilitator took detailed notes and verified their accuracy with participants during the sessions; a second member of the research team observed and verified the recorded notes. Three coders performed a thematic analysis, and the other authors reviewed it.
Forty-three trainees and 50 mentors participated. Trainees and mentors had diverging views on the role of mentoring in fostering communication skills development. Trainees expressed varying levels of self-confidence but considerable angst. Mentors felt that most trainees have low self-confidence. Trainees expressed interest in learning scientific communication skills, but mentors reported that some trainees were insufficiently motivated and seemed resistant to guidance. Both groups agreed that trainees found mentors’ feedback difficult to accept.
The degree of distress, dissatisfaction, and lack of mutual understanding between mentors and trainees was striking. These themes have important implications for best practices and resource development.
PMCID: PMC3809893  PMID: 23969363
15.  Peer mentoring: evaluation of a novel programme in paediatrics 
Archives of Disease in Childhood  2013;99(2):142-146.
Mentoring is important for personal and professional development of doctors. Peer mentoring is a core skill in the UK paediatric postgraduate curriculum. However, there is a paucity of peer mentoring programmes aimed at postgraduate doctors in training (postgraduate trainees), and there are no such schemes within paediatrics described in the literature. We developed a regional peer mentoring programme for postgraduate trainees in paediatrics to assess demand and need for peer mentoring and to explore the benefits for both peer mentees and mentors.
Programme design
Junior postgraduate trainees, randomly selected from volunteers, received peer mentoring from more senior trainees for 1 year. Peer mentors were selected by competitive application and undertook tailored training followed by an experiential learning programme. The programme was evaluated using structured questionnaires.
90% (76/84) of first-year postgraduate trainees in paediatrics applied to participate, demonstrating high demand. 18 peer mentor–mentee pairs were matched. Peer mentors and mentees reported high satisfaction rates, acquisition of new and transferable skills and changed behaviours. All peer mentors intended to use the skills in their workplace and, later, as an educational supervisor.
Our programme represents a novel approach to meeting the demonstrated demand and the curriculum requirement for peer mentoring, and enabled peer mentors and mentees to develop a valuable and versatile skill set. To our knowledge, it is the first such programme in paediatrics and provides a feasibility model that may be adapted locally to allow education providers to offer this important experience to postgraduate trainees.
PMCID: PMC3913287  PMID: 24152570
Medical Education; General Paediatrics
16.  Learning styles and approaches to learning among medical undergraduates and postgraduates 
BMC Medical Education  2013;13:42.
The challenge of imparting a large amount of knowledge within a limited time period in a way it is retained, remembered and effectively interpreted by a student is considerable. This has resulted in crucial changes in the field of medical education, with a shift from didactic teacher centered and subject based teaching to the use of interactive, problem based, student centered learning. This study tested the hypothesis that learning styles (visual, auditory, read/write and kinesthetic) and approaches to learning (deep, strategic and superficial) differ among first and final year undergraduate medical students, and postgraduates medical trainees.
We used self administered VARK and ASSIST questionnaires to assess the differences in learning styles and approaches to learning among medical undergraduates of the University of Colombo and postgraduate trainees of the Postgraduate Institute of Medicine, Colombo.
A total of 147 participated: 73 (49.7%) first year students, 40 (27.2%) final year students and 34(23.1%) postgraduate students. The majority (69.9%) of first year students had multimodal learning styles. Among final year students, the majority (67.5%) had multimodal learning styles, and among postgraduates, the majority were unimodal (52.9%) learners.
Among all three groups, the predominant approach to learning was strategic. Postgraduates had significant higher mean scores for deep and strategic approaches than first years or final years (p < 0.05). Mean scores for the superficial approach did not differ significantly between groups.
The learning approaches suggest a positive shift towards deep and strategic learning in postgraduate students. However a similar difference was not observed in undergraduate students from first year to final year, suggesting that their curriculum may not have influenced learning methodology over a five year period.
PMCID: PMC3620557  PMID: 23521845
Learning methods; Medicine; Post graduate; Undergraduate curriculum evaluation
17.  Modification of Peyton’s four-step approach for small group teaching – a descriptive study 
BMC Medical Education  2014;14:68.
Skills-lab training as a methodological teaching approach is nowadays part of the training programs of almost all medical faculties. Specific ingredients have been shown to contribute to a successful learning experience in skills-labs. Although it is undoubted that the instructional approach used to introduce novel clinical technical skills to learners has a decisive impact on subsequent skills performance, as yet, little is known about differential effects of varying instructional methods. An instructional approach that is becoming increasingly prevalent in medical education is “Peyton’s Four-Step Approach”. As Peyton’s Four Step Approach was designed for a 1:1 teacher : student ratio, the aim of the present study was to develop and evaluate a modified Peyton’s Approach for small group teaching.
The modified Peyton’s Approach was applied in three skills-lab training sessions on IV catheter insertion, each with three first- or second year medical students (n = 9), delivered by three different skills-lab teachers. The presented descriptive study investigated the practicability and subjective impressions of skills-lab trainees and tutors. Skills-lab sessions were evaluated by trainees’ self-assessment, expert ratings, and qualitative analysis of semi-standardized interviews conducted with trainees and tutors.
The model was well accepted by trainees, and was rated as easy to realize, resulting in a good flow of teaching and success in attracting trainee’s attention when observed by expert raters. Qualitative semi-standardized interviews performed with all of the trainees and tutors revealed that trainees valued repeated observation, instruction of trainees and the opportunity for independent performance, while tutors stressed that trainees were highly concentrated throughout the training and that they perceived repeated observation to be a valuable preparation for their own performance.
The modified Peyton’s Approach to instruct small groups of students in skills-lab training sessions has revealed to be practicable, well accepted by trainees, and easy for tutors to realize. Further research should address the realization of the model in larger skills-lab training groups.
PMCID: PMC3976361  PMID: 24690457
Undergraduate medical education; Clinical skills; Catheter insertion; Simulation; Instructional approach; Peyton; Small group teaching
18.  Maximising harm reduction in early specialty training for general practice: validation of a safety checklist 
BMC Family Practice  2012;13:62.
Making health care safer is a key policy priority worldwide. In specialty training, medical educators may unintentionally impact on patient safety e.g. through failures of supervision; providing limited feedback on performance; and letting poorly developed behaviours continue unchecked. Doctors-in-training are also known to be susceptible to medical error. Ensuring that all essential educational issues are addressed during training is problematic given the scale of the tasks to be undertaken. Human error and the reliability of local systems may increase the risk of safety-critical topics being inadequately covered. However adherence to a checklist reminder may improve the reliability of task delivery and maximise harm reduction. We aimed to prioritise the most safety-critical issues to be addressed in the first 12-weeks of specialty training in the general practice environment and validate a related checklist reminder.
We used mixed methods with different groups of GP educators (n = 127) and specialty trainees (n = 9) in two Scottish regions to prioritise, develop and validate checklist content. Generation and refinement of checklist themes and items were undertaken on an iterative basis using a range of methods including small group work in dedicated workshops; a modified-Delphi process; and telephone interviews. The relevance of potential checklist items was rated using a 4-point scale content validity index to inform final inclusion.
14 themes (e.g. prescribing safely; dealing with medical emergency; implications of poor record keeping; and effective & safe communication) and 47 related items (e.g. how to safety-net face-to-face or over the telephone; knowledge of practice systems for results handling; recognition of harm in children) were judged to be essential safety-critical educational issues to be covered. The mean content validity index ratio was 0.98.
A checklist was developed and validated for educational supervisors to assist in the reliable delivery of safety-critical educational issues in the opening 12-week period of training, and aligned with national curriculum competencies. The tool can also be adapted for use as a self-assessment instrument by trainees to guide patient safety-related learning needs. Dissemination and implementation of the checklist and self-rating scale are proceeding on a national, voluntary basis with plans to evaluate its feasibility and educational impact.
PMCID: PMC3418214  PMID: 22721273
19.  The Clinical Education Partnership Initiative: an innovative approach to global health education 
BMC Medical Education  2014;14:1043.
Despite evidence that international clinical electives can be educationally and professionally beneficial to both visiting and in-country trainees, these opportunities remain challenging for American residents to participate in abroad. Additionally, even when logistically possible, they are often poorly structured. The Universities of Washington (UW) and Nairobi (UoN) have enjoyed a long-standing research collaboration, which recently expanded into the UoN Medical Education Partnership Initiative (MEPI). Based on MEPI in Kenya, the Clinical Education Partnership Initiative (CEPI) is a new educational exchange program between UoN and UW. CEPI allows UW residents to partner with Kenyan trainees in clinical care and teaching activities at Naivasha District Hospital (NDH), one of UoN’s MEPI training sites in Kenya.
UW and UoN faculty collaborated to create a curriculum and structure for the program. A Chief Resident from the UW Department of Medicine coordinated the program at NDH. From August 2012 through April 2014, 32 UW participants from 5 medical specialties spent between 4 and 12 weeks working in NDH. In addition to clinical duties, all took part in formal and informal educational activities. Before and after their rotations, UW residents completed surveys evaluating clinical competencies and cross-cultural educational and research skills. Kenyan trainees also completed surveys after working with UW residents for three months.
UW trainees reported a significant increase in exposure to various tropical and other diseases, an increased sense of self-reliance, particularly in a resource-limited setting, and an improved understanding of how social and cultural factors can affect health. Kenyan trainees reported both an increase in clinical skills and confidence, and an appreciation for learning a different approach to patient care and professionalism.
After participating in CEPI, both Kenyan and US trainees noted improvement in their clinical knowledge and skills and a broader understanding of what it means to be clinicians. Through structured partnerships between institutions, educational exchange that benefits both parties is possible.
Electronic supplementary material
The online version of this article (doi:10.1186/s12909-014-0246-5) contains supplementary material, which is available to authorized users.
PMCID: PMC4335420  PMID: 25547408
International; Clinical rotation; Medical education; Residents; Kenya
20.  Why peer assessment helps to improve clinical performance in undergraduate physical therapy education: a mixed methods design 
BMC Medical Education  2014;14:117.
Peer Assessment (PA) in health professions education encourages students to develop a critical attitude towards their own and their peers’ performance. We designed a PA task to assess students’ clinical skills (including reasoning, communication, physical examination and treatment skills) in a role-play that simulated physical therapy (PT) practice. Students alternately performed in the role of PT, assessor, and patient. Oral face-to-face feedback was provided as well as written feedback and scores.
This study aims to explore the impact of PA on the improvement of clinical performance of undergraduate PT students.
The PA task was analyzed and decomposed into task elements. A qualitative approach was used to explore students’ perceptions of the task and the task elements. Semi-structured interviews with second year students were conducted to explore the perceived impact of these task elements on performance improvement. Students were asked to select the elements perceived valuable, to rank them from highest to lowest learning value, and to motivate their choices. Interviews were transcribed verbatim and analyzed, using a phenomenographical approach and following template analysis guidelines. A quantitative approach was used to describe the ranking results.
Quantitative analyses showed that the perceived impact on learning varied widely. Performing the clinical task in the PT role, was assigned to the first place (1), followed by receiving expert feedback (2), and observing peer performance (3). Receiving peer feedback was not perceived the most powerful task element.
Qualitative analyses resulted in three emerging themes: pre-performance, true-performance, and post-performance triggers for improvement. Each theme contained three categories: learning activities, outcomes, and conditions for learning.
Intended learning activities were reported, such as transferring prior learning to a new application context and unintended learning activities, such as modelling a peer’s performance. Outcomes related to increased self-confidence, insight in performance standards and awareness of improvement areas. Conditions for learning referred to the quality of peer feedback.
PA may be a powerful tool to improve clinical performance, although peer feedback is not perceived the most powerful element. Peer assessors in undergraduate PT education use idiosyncratic strategies to assess their peers’ performance.
PMCID: PMC4064265  PMID: 24928420
Peer assessment; Peer feedback; Self-assessment; Clinical performance
21.  An innovative OSCE clinical log station: a quantitative study of its influence on Log use by medical students 
BMC Medical Education  2012;12:111.
A Clinical Log was introduced as part of a medical student learning portfolio, aiming to develop a habit of critical reflection while learning was taking place, and provide feedback to students and the institution on learning progress. It was designed as a longitudinal self-directed structured record of student learning events, with reflection on these for personal and professional development, and actions planned or taken for learning.
As incentive was needed to encourage student engagement, an innovative Clinical Log station was introduced in the OSCE, an assessment format with established acceptance at the School. This study questions: How does an OSCE Clinical Log station influence Log use by students?
The Log station was introduced into the formative, and subsequent summative, OSCEs with careful attention to student and assessor training, marking rubrics and the standard setting procedure. The scoring process sought evidence of educational use of the log, and an ability to present and reflect on key learning issues in a concise and coherent manner.
Analysis of the first cohort’s Log use over the four-year course (quantified as number of patient visits entered by all students) revealed limited initial use. Usage was stimulated after introduction of the Log station early in third year, with some improvement during the subsequent year-long integrated community-based clerkship. Student reflection, quantified by the mean number of characters in the ‘reflection’ fields per entry, peaked just prior to the final OSCE (mid-Year 4). Following this, very few students continued to enter and reflect on clinical experience using the Log.
While the current study suggested that we can’t assume students will self-reflect unless such an activity is included in an assessment, ongoing work has focused on building learner and faculty confidence in the value of self-reflection as part of being a competent physician.
PMCID: PMC3511194  PMID: 23140250
Medical education; Electronic reflective clinical log; Assessment; OSCE log station
22.  Optimizing the Implementation of Practice Improvement Modules in Training: Lessons from Educators 
The American Board of Internal Medicine approved the use of Practice Improvement Modules (PIMs) to help training programs teach and assess practice-based learning and improvement (PBLI) and systems-based practice (SBP).
We surveyed individuals who ordered a PIM in a residency or fellowship training program between June 2006 and August 2009. The 43 programs that volunteered to participate completed a 30-minute anonymous online survey.
Program directors or associate program directors led the PIM process in 30 programs (70%). Trainees' degrees of involvement in PIMs were highly variable between programs, and several respondents felt that trainees were either not sufficiently engaged or not engaged with enough consistency. The most common activity for trainee involvement was data collection through patient surveys or chart review, although only 17 programs (40%) provided protected time for this activity. Few trainees participated in higher level activities such as data analysis or identification for areas of improvement or were given leadership roles; yet most respondents reported that completing the PIM helped trainees learn basic principles of QI and develop competence in PBLI and SBP and that PIM completion improved the program's ability to develop QI initiatives and resulted in program or institutional improvements, including sustainable improvement in patient care. Most respondents reported that the outcome warranted the effort to complete PIMs.
PIMs may be a valuable but underused educational experience for trainees as well as training programs. Focusing on particular themes and facets of PIMs may facilitate implementation.
PMCID: PMC3613323  PMID: 24404231
23.  Pediatric resident and faculty attitudes toward self-assessment and self-directed learning: a cross-sectional study 
The development of self-assessment and self-directed learning skills is essential to lifelong learning and becoming an effective physician. Pediatric residents in the United States are now required to use Individualized Learning Plans (ILPs) to document self-assessment and self-directed learning. A better understanding of resident and faculty attitudes and skills about self-assessment and self-directed learning will allow more successful integration of lifelong learning into residency education. The objective of this study was to compare faculty and resident attitudes, knowledge and skills about self-assessment, self-directed learning and ILPs.
Survey of pediatric residents and faculty at a single institution. Respondents rated their attitudes, knowledge, and self-perceived skills surrounding self-assessment, self-directed learning and ILPs.
Overall survey response rate was 81% (79/97); 100% (36/36) residents and 70% (43/61) faculty. Residents and faculty agreed that lifelong learning is a necessary part of being a physician. Both groups were comfortable with assessing their own strengths and weaknesses and developing specific goals to improve their own performance. However, residents were less likely than faculty to continuously assess their own performance (44% vs. 81%; p < 0.001) or continuously direct their own learning (53% vs. 86%; p < 0.001). Residents were more likely than faculty to believe that residents should be primarily responsible for directing their own learning (64% vs. 19%; p < 0.0001), but at the same time, more residents believed that assigned clinical (31% vs. 0%; p < 0.0001) or curricular (31% vs. 0%; p < 0.0001) experiences were sufficient to make them competent physicians. Interns were less likely than senior residents to have a good understanding of how to assess their own skills (8% vs. 58%; p = 0.004) or what it means to be a self-directed learner (50% vs. 83%; p = 0.04).
Qualitative comments indicated that while ILPs have the potential to help learners develop individualized, goal-directed learning plans based on strengths and weaknesses, successful implementation will require dedicated time and resident and faculty development.
These findings suggest that training and experience are necessary for physicians to understand the role of self-directed learning in education. Deliberate practice, for example by requiring residents to use ILPs, may facilitate self-directed, lifelong learning.
PMCID: PMC2673219  PMID: 19364401
24.  Does interprofessional simulation increase self-efficacy: a comparative study 
BMJ Open  2015;5(1):e005472.
In this work, we have compared uniprofessional and interprofessional versions of a simulation education intervention, in an attempt to understand more about whether it improves trainees’ self-efficacy.
Interprofessionalism has been climbing the healthcare agenda for over 50 years. Simulation education attempts to create an environment for healthcare professionals to learn, without potential safety risks for patients. Integrating simulation and interprofessional education can provide benefits to individual learners.
The intervention took place in a high-fidelity simulation facility located on the campus of a large urban hospital. The centre provides educational activities for an Academic Health Sciences Centre. Approximately 2500 staff are trained at the centre each year.
One hundred and fifteen nurses and midwives along with 156 doctors, all within the early years of their postgraduate experience participated. All were included on the basis of their ongoing postgraduate education.
Each course was a one-day simulation course incorporating five clinical and one communication scenarios. After each a facilitated debriefing took place. A mixed methods approach utilised precourse and postcourse questionnaires measuring self-efficacy in managing emergency situations, communication, teamwork and leadership.
Thematic analysis of qualitative data showed improvements in communication/teamwork and leadership, for doctors and nurses undergoing simulation training. These findings were confirmed by statistical analysis showing that confidence ratings improved in nurses and doctors overall (p<0.001). Improved outcomes from baseline were observed for interprofessional versus uniprofessional trained nurses (n=115; p<0.001). Postcourse ratings for doctors showed that interprofessional training was significantly associated with better final outcomes for a communication/teamwork dimension (n=156; p<0.05).
This study provides evidence that simulation training enhances participants’ self-efficacy in clinical situations. It also leads to increases in their perceived abilities relating to communication/teamwork and leadership/management of clinical scenarios. Interprofessional training showed increased positive effects on self-efficacy for nurses and doctors.
PMCID: PMC4298099  PMID: 25586366
25.  Extension of a genetic network model by iterative experimentation and mathematical analysis 
Molecular Systems Biology  2005;1:2005.0013.
We extend the current model of the plant circadian clock, in order to accommodate new and published data. Throughout our model development we use a global parameter search to ensure that any limitations we find are due to the network architecture and not to our selection of the parameter values, which have not been determined experimentally. Our final model includes two, interlocked loops of gene regulation and is reminiscent of the circuit structures previously identified by experiments on insect and fungal clocks. It is the first Arabidopsis clock model to show such good correspondence to experimental data.Our interlocked feedback loop model predicts the regulation of two unknown components. Experiments motivated by these predictions identify the GIGANTEA gene as a strong candidate for one component, with an unexpected pattern of light regulation.*
This study involves an iterative approach of mathematical modelling and experiment to develop an accurate mathematical model of the circadian clock in the higher plant Arabidopsis thaliana. Our approach is central to systems biology and should lead to a greater, quantitative understanding of the circadian clock, as well as being more widely relevant to research into genetic networks.
The day–night cycle caused by the Earth's rotation affects most organisms, and has resulted in the evolution of the circadian clock. The circadian clock controls 24-h rhythms in processes from metabolism to behaviour; in higher eukaryotes, the circadian clock controls the rhythmic expression of 5–10% of genes. In plants, the clock controls leaf and petal movements, the opening and closing of stomatal pores, the discharge of floral fragrances and many metabolic activities, especially those associated with photosynthesis.
The relatively small number of components involved in the central circadian network makes it an ideal candidate for mathematical modelling of complex biological regulation. Genetic studies in a variety of model organisms have shown that the circadian rhythm is generated by a central network of between 6 and 12 genes. These genes form feedback loops generating a rhythm in mRNA production. One negative feedback loop in which a gene encodes a protein that, after several hours, turns off transcription is, in principle, capable of creating a circadian rhythm. However, real circadian clocks have proven to be more complicated than this, with interlocked feedback loops. Networks of this complexity are more easily understood through mathematical modelling.
The clock mechanism in the model plant, A. thaliana, was first proposed to comprise a feedback loop in which two partially redundant genes, LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1), repress the expression of their activator, TIMING OF CAB EXPRESSION 1 (TOC1). We previously modelled this preliminary network and showed that it was not capable of recreating several important pieces of experimental data (Locke et al, 2005). Here, we extend the LHY/CCA1–TOC1 network in new mathematical models. To check the effects of each addition to the network, the outputs of the extended models are compared to published data and to new experiments.
As is the case for most biological networks, the parameter values in our model, such as the translation rate of TOC1 protein, are unknown. We employ here an optimisation method, which works well with noisy and varied data and allows a global search of parameter space. This should ensure that the limitations we find in our networks are due to the network structure, and not to our parameter choices.
Our final interlocked feedback loop model requires two hypothetical components, genes X and Y (Figure 4), but is the first Arabidopsis clock model to exhibit such a good correspondence with experimental data. The model simulates a residual short-period oscillation in the cca1;lhy mutant, as characterised by our experiments. No single-loop model is able to do this. Our model also matches experimental data under constant light (LL) conditions and correctly senses photoperiod. The model predicts an interlocked feedback loop structure similar to that seen in the circadian clock mechanisms of other organisms.
The interlocked feedback loop model predicts a distinctive pattern of Y mRNA accumulation in the wild type (WT) and in the cca1;lhy double mutant, with Y mRNA levels increasing transiently at dawn. We designed an experiment to identify Y based on this prediction. GIGANTEA (GI) mRNA levels fit very well to our predicted profile for Y (Figure 6), identifying GI as a strong candidate for Y.
The approach described here could act as a template for experimental biologists seeking to extend models of small genetic networks. Our results illustrate the usefulness of mathematical modelling in guiding experiments, even if the models are based on limited data. Our method provides a way of identifying suitable candidate networks and quantifying how these networks better describe a wide variety of experimental measurements. The characteristics of new putative genes are thereby obtained, facilitating the experimental search for new components. To facilitate future experimental design, we provide user-friendly software that is specifically designed for numerical simulation of circadian experiments using models for several species (Brown, 2004b).
*Footnote: Synopsis highlights were added on 5 July 2005.
Circadian clocks involve feedback loops that generate rhythmic expression of key genes. Molecular genetic studies in the higher plant Arabidopsis thaliana have revealed a complex clock network. The first part of the network to be identified, a transcriptional feedback loop comprising TIMING OF CAB EXPRESSION 1 (TOC1), LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1), fails to account for significant experimental data. We develop an extended model that is based upon a wider range of data and accurately predicts additional experimental results. The model comprises interlocking feedback loops comparable to those identified experimentally in other circadian systems. We propose that each loop receives input signals from light, and that each loop includes a hypothetical component that had not been explicitly identified. Analysis of the model predicted the properties of these components, including an acute light induction at dawn that is rapidly repressed by LHY and CCA1. We found this unexpected regulation in RNA levels of the evening-expressed gene GIGANTEA (GI), supporting our proposed network and making GI a strong candidate for this component.
PMCID: PMC1681447  PMID: 16729048
biological rhythms; gene network; mathematical modelling; parameter estimation

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