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1.  Can Perioperative Chemotherapy for Advanced Gastric Cancer Be Recommended on the Basis of Current Research? A Critical Analysis 
Journal of Gastric Cancer  2014;14(1):39-46.
According to current guidelines, perioperative chemotherapy is an integral part of the treatment strategy for advanced gastric cancer. Randomized controlled studies have been conducted in order to determine whether perioperative chemotherapy leads to improved R0 resection rates, fewer recurrences, and prolonged survival. The aim of our project was to critically appraise three major studies to establish whether perioperative chemotherapy for advanced, potentially resectable gastric cancer can be recommended on the basis of their findings.
Materials and Methods
We analyzed the validity of the three most important studies (MAGIC, ACCORD, and EORTC) using a standardized questionnaire. Each study was evaluated for the study design, patient selection, randomization, changes in protocol, participating clinics, preoperative staging, chemotherapy, homogeneity of subjects, surgical quality, analysis of the results, and recruitment period.
All three studies had serious shortcomings with respect to patient selection, homogeneity of subjects, changes in protocol, surgical quality, and analysis of the results. The protocols of the MAGIC and ACCORD-studies were changed during the study period because of insufficient recruitment, such that carcinomas of the lower esophagus and the stomach were examined collectively. In neither the MAGIC study nor the ACCORD study did patients undergo adequate lymphadenectomy, and only about half of the patients in the chemotherapy group could undergo the treatment specified in the protocol. The EORTC study had insufficient statistical power.
We concluded that none of the three studies was sufficiently robust to justify an unrestrained recommendation for perioperative chemotherapy in cases of advanced gastric cancer.
PMCID: PMC3996248  PMID: 24765536
Perioperative chemotherapy; Lower esophageal cancer; Stomach neoplasms; Cancer of the esophagogastric junction
3.  Form follows function: pragmatic controlled trials (PCTs) have to answer different questions and require different designs than randomized controlled trials (RCTs) 
Rising concern for demonstrated real world comparative effectiveness has heightened interest in “pragmatic trials” design. Pragmatic trials investigate whether the efficacy, presumed or found in explanatory trials under ideal conditions, can also be detected under real world conditions, i.e. effectiveness. It is also recognized that ‘real world’ effects which are usually addressed in public health research gain growing interest in confirming the ‘road capability’ of results obtained under ideal study conditions. This paper demonstrates that studies under ideal or real world conditions use different methods, generate different information and cannot replace each other.
Subjects and methods
The PCT design meets four requirements of public health and of effectiveness research. It includes all individuals who presented with the selected condition. It classifies the included individuals according to baseline risks. It enables plausibility controls. Finally, it compares the outcomes resulting from specified and not-specified interventions or treatments.
We propose a pragmatic controlled trial (PCT) design in which patient preference and other co-factors crucial in determining the actual effectiveness of interventional options will not be neutralized by concealed randomization and blinding. This design is applicable to record the selected interventions and generated outcomes in day-to-day health care and is capable of incorporating preference and other participative factors into assessment of effectiveness.
The PCT design is useful for public health research, e.g. the effectiveness of interventions to change smoking habits or to prevent death from breast cancer, as well as for comparative effectiveness research where it will supplement the traditional randomized controlled trial (RCT).
PMCID: PMC3655212  PMID: 23687408
Randomized controlled trial (RCT); Pragmatic controlled trial (PCT); Public health research; Comparative effectiveness research; Internal validity; External validity
4.  Visual Aids for Multimodal Treatment Options to Support Decision Making of Patients with Colorectal Cancer 
A variety of multimodal treatment options are available for colorectal cancer and many patients want to be involved in decisions about their therapies. However, their desire for autonomy is limited by lack of disease-specific knowledge. Visual aids may be helpful tools to present complex data in an easy-to-understand, graphic form to lay persons. The aim of the present study was to evaluate the treatment preferences of healthy persons and patients using visual aids depicting multimodal treatment options for colorectal cancer.
We designed visual aids for treatment scenarios based on four key studies concerning multimodal treatment of colorectal cancer. The visual aids were composed of diagrams depicting outcome parameters and side effects of two treatment options. They were presented to healthy persons (n = 265) and to patients with colorectal cancer (n = 102).
Most patients and healthy persons could make immediate decisions after seeing the diagrams (range: 88% – 100%). Patients (79%) chose the intensive-treatment option in the scenario with a clear survival benefit. In scenarios without survival benefit, all groups clearly preferred the milder treatment option (range: 78% - 90%). No preference was seen in the scenario depicting equally intense treatment options with different timing (neoadjuvant vs. adjuvant) but without survival benefit.
Healthy persons’ and patients’ decisions using visual aids seem to be influenced by quality-of-life aspects rather than recurrence rates especially in situations without survival benefit. In the future visual aids may help to improve the management of patients with colorectal cancer.
PMCID: PMC3502169  PMID: 23092310
Visual aids; Colorectal cancer; Quality of life; Side effects; Shared decision-making
5.  Preferences of diabetes patients and physicians: A feasibility study to identify the key indicators for appraisal of health care values 
Evidence-based medicine, the Institute of Medicine (IOM) and the German Institute for Quality and Efficiency in Health Care (IQWiG), support the inclusion of patients' preferences in health care decisions. In fact there are not many trials which include an assessment of patient's preferences. The aim of this study is to demonstrate that preferences of physicians and of patients can be assessed and that this information may be helpful for medical decision making.
One of the established methods for assessment of preferences is the conjoint analysis. Conjoint analysis, in combination with a computer assisted telephone interview (CATI), was used to collect data from 827 diabetes patients and 60 physicians, which describe the preferences expressed as levels of four factors in the management and outcome of the disease. The first factor described the main treatment effect (reduction of elevated HbA1c, improved well-being, absence of side effects, and no limitations of daily life). The second factor described the effect on the body weight (gain, no change, reduction). The third factor analyzed the mode of application (linked to meals or flexible application). The fourth factor addressed the type of product (original brand or generic product). Utility values were scaled and normalized in a way that the sum of utility points across all levels is equal to the number of attributes (factors) times 100.
The preference weights confirm that the reduction of body weight is at least as important for patients - especially obese patients - and physicians as the reduction of an elevated HbA1c. Original products were preferred by patients while general practitioners preferred generic products.
Using the example of diabetes, the difference between patients' and physicians' preferences can be assessed. The use of a conjoint analysis in combination with CATI seems to be an effective approach for generation of data which are needed for policy and medical decision making in health care.
PMCID: PMC2989314  PMID: 21050469
6.  Qualitative assessment of innovations in healthcare provision 
The triad of quality, innovation and economic restraint is as important in health care as it is in the business world. There are many proposals for the assessment of quality and of economic restraints in health care but only a few address assessment of innovations. We propose a strategy and new structures to standardize the description of health care innovations and to quantify them.
Strategy and structure are based on the assumption that in the early phase of an innovation only data on the feasibility and possibly on the efficacy or effectiveness of an innovation can be expected. From the patient's perspective, benefit resulting from an innovation can be confirmed only in a later phase of development. Early indicators of patient's benefit will be surrogate parameters which correlate only weakly with the desired endpoints. After the innovation has been in use, there will be more evidence on correlations between surrogate parameters and the desired endpoints to provide evidence of the patient benefit. From an administrative perspective, this evidence can be considered in decisions about public financing. Different criteria are proposed for the assessment of innovations in prevention, diagnosis and therapy. For decisions on public financing a public fund for innovations may be helpful. Depending on the phase of innovation risk sharing models are proposed between manufacturers, private insurers and public funding.
Potential for patient benefit is always uncertain during early stages of innovations. This uncertainty decreases with increasing information on the effects of the innovation. Information about an innovation can be quantified, categorized and integrated into rational economic decisions.
PMCID: PMC2666677  PMID: 19298658
7.  The value of health care – a matter of discussion in Germany 
Interest in assessing the value of health-care services in Germany has considerably increased since the foundation of the Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen, IQWiG (Institute for Quality and Efficiency in Health Care). The practical application of value assessment illustrates how problematic the process can be. In all decisions made for the provision of health care, data concerning the measurable dimensions (quantity and quality of efficacy and effectiveness, validity of the results and costs) flow into a complex and not yet standardized decision-making process concerning public financing. Some of these decisions are based on data of uncertain validity, unknown reproducibility and unclear appropriateness.
In this paper we describe the theoretical aspects of value from psychological and economic viewpoints and discuss national and international approaches. Methodic details and difficulties in assessing the value of health-care services are analysed. A definition of the intangible value of health-care services will be proposed which contains only three factors: the absolute risk reduction (usually a measure of efficacy), the validity of the scientific papers examined and the type of the expected effectiveness (prevention of death and disability, restitution of well-being). The intangible value describes the additional benefit when comparing two possible actions, like treatment or observation only.
The description of intangible value from the viewpoint of different stakeholders is a useful measure for subsequent steps (not discussed here) – the evaluation of costs and of patient benefit. A standardised, transparent, fair and democratic evaluation is essential for the definition of a basic benefit package.
PMCID: PMC1764870  PMID: 17199886
8.  The fading of reported effectiveness. A meta-analysis of randomised controlled trials 
The "real" effect size of a medical therapy is constant over time. In contrast, the effect size reported in randomised controlled trials (RCTs) may change over time because the sum of all kinds of bias influencing the reported effectiveness is not necessarily constant. As this would affect the validity of meta-analyses, we tested the hypothesis that the reported effect size decreases over time. Furthermore, we tested three hypotheses that would explain a possible change.
Because of well established outcome measures, the lipid-lowering drugs Pravastatin and Atorvastatin (serum low-density lipoprotein cholesterol, LDL-C) and the anti-glaucoma drugs Timolol and Latanoprost (intraocular pressure, IOP) were chosen for this investigation. Studies were identified by a standardized MEDLINE search. RCTs investigating the above identified medications administered as monotherapy, and in defined dosages, were included. Publication year, baseline (= pre-treatment value in the treatment group of interest) and post intervention means, number of patients and the assignment to experimental or control group were extracted for each study.
A total of 625 citations were screened; 206 met the inclusion criteria. The reported effect size of Pravastatin (change of reported effect size in five years: -3.22% LDL-C, P < .0001), Timolol (-0.56 mmHg, P < .0001) and Latanoprost (-1.78 mmHg, P = .0074) decreased over time, while there was no significant change for Atorvastatin (+0.31% LDL-C, P = .8618). Multiple regression analysis showed that baseline values were the most important influencing factor; study size or treatment group did not play a significant role.
The effectiveness of medical therapies reported in RCTs decreases over time in three of the four investigated pharmaceuticals, caused mainly by baseline differences. We call this phenomenon "fading of reported effectiveness". Under this condition the validity of a meta-analysis may be impaired. Therefore we propose to observe this phenomenon in future meta-analyses in order to guarantee a maximum of transparency.
PMCID: PMC1479361  PMID: 16689990
9.  Sicily statement on evidence-based practice 
A variety of definitions of evidence-based practice (EBP) exist. However, definitions are in themselves insufficient to explain the underlying processes of EBP and to differentiate between an evidence-based process and evidence-based outcome. There is a need for a clear statement of what Evidence-Based Practice (EBP) means, a description of the skills required to practise in an evidence-based manner and a curriculum that outlines the minimum requirements for training health professionals in EBP. This consensus statement is based on current literature and incorporating the experience of delegates attending the 2003 Conference of Evidence-Based Health Care Teachers and Developers ("Signposting the future of EBHC").
Evidence-Based Practice has evolved in both scope and definition. Evidence-Based Practice (EBP) requires that decisions about health care are based on the best available, current, valid and relevant evidence. These decisions should be made by those receiving care, informed by the tacit and explicit knowledge of those providing care, within the context of available resources.
Health care professionals must be able to gain, assess, apply and integrate new knowledge and have the ability to adapt to changing circumstances throughout their professional life. Curricula to deliver these aptitudes need to be grounded in the five-step model of EBP, and informed by ongoing research. Core assessment tools for each of the steps should continue to be developed, validated, and made freely available.
All health care professionals need to understand the principles of EBP, recognise EBP in action, implement evidence-based policies, and have a critical attitude to their own practice and to evidence. Without these skills, professionals and organisations will find it difficult to provide 'best practice'.
PMCID: PMC544887  PMID: 15634359
10.  A new instrument to describe indicators of well-being in old-old patients with severe dementia – The Vienna List 
In patients with very severe dementia self-rating of quality of life usually is not possible and appropriate instruments for proxy-ratings are not available. The aim of this project is to develop an instrument of clinical proxy-ratings for this population.
Using electronic instruments, physicians and nurses recorded patient behaviour and changes of behaviour over a period of one year. Based on these data a list of 65 items was generated and subsequently allocated to 14 categories. This list was tested in 217 patients (61–105 yrs) with dementia diagnosed according to ICD-10 by both physicians and nurses. The severity of dementia was assessed by means of the Global Deterioration Scale (GDS) and the Brief Cognitive Rating Scale (BCRS). The Spitzer-Index (proxy-rating) was used as a global quality of life measure. Activity of daily living was rated using the Barthel Index.
A factor analysis of the original 65 items revealed 5 factors (communication, negative affect, bodily contact, aggression, and mobility). By stepwise removing items we obtained satisfactory internal consistencies of the factors both for nurses' and physicians' ratings. The factors were generally unrelated. The validity of the instrument was proven by correlations of the factors communication and mobility with the Brief Cognitive Rating Scale (BCRS) and the Barthel-Index.
The results demonstrate the reliability and validity of the Vienna List as a proxy rating measurement of quality of life in patients with severe dementia. The psychometric properties of the scale have to be proved in further studies.
PMCID: PMC395842  PMID: 14975057
well-being; quality of life; old-old; severe dementia

Results 1-10 (10)