Genes associated with cardiovascular disease may also be risk factors for congenital cerebral palsy (CP) and these associations may be modified by sex, since there is an increased risk of CP in male children. We investigated the association between CP of the child with cardiovascular disease in parents, taking sex of the child into consideration.
All parents of non-adopted singletons born in Denmark between 1973 and 2003 were included. Parents of a child with CP, confirmed by the Danish National CP registry, were considered exposed. Cox proportional hazards regressions were used to model risk of cardiovascular outcomes for exposed parents compared to all other parents beginning at the child’s 10th birthday.
We identified 733,730 mothers and 666,652 fathers among whom 1,592 and 1,484, respectively, had a child with CP. The mean age for mothers at end of follow up was 50±8 years. After adjustment for maternal age, parental education, child’s sex, child’s residence, child being small for gestational age and maternal hypertensive disorder during pregnancy, mothers of CP male children had an excess risk of cardiovascular disease (HR: 1.52, 95% CI: 1.16-2.00), attributable mostly to an increased incidence of hypertension and cerebrovascular disease. After additional adjustment for preterm birth, the association was markedly attenuated for cardiovascular disease (1.34, 95%CI: 1.02 - 1.76), became nonsignificant for hypertension, but remained significant for cerebrovascular disease (HR: 2.73, 95% CI: 1.45- 5.12). There was no increased risk of cardiovascular events in mothers of female CP children, or fathers of CP children of any sex.
Women that have a male child with CP are at increased risk for premature cardiovascular disease. Part of this association may be related to risk factors for preterm births.
In fledgling areas of research, evidence supporting causal assumptions is often scarce due to the small number of empirical studies conducted. In many studies it remains unclear what impact explicit and implicit causal assumptions have on the research findings; only the primary assumptions of the researchers are often presented. This is particularly true for research on the effect of faculty’s teaching performance on their role modeling. Therefore, there is a need for robust frameworks and methods for transparent formal presentation of the underlying causal assumptions used in assessing the causal effects of teaching performance on role modeling. This study explores the effects of different (plausible) causal assumptions on research outcomes.
This study revisits a previously published study about the influence of faculty’s teaching performance on their role modeling (as teacher-supervisor, physician and person). We drew eight directed acyclic graphs (DAGs) to visually represent different plausible causal relationships between the variables under study. These DAGs were subsequently translated into corresponding statistical models, and regression analyses were performed to estimate the associations between teaching performance and role modeling.
The different causal models were compatible with major differences in the magnitude of the relationship between faculty’s teaching performance and their role modeling. Odds ratios for the associations between teaching performance and the three role model types ranged from 31.1 to 73.6 for the teacher-supervisor role, from 3.7 to 15.5 for the physician role, and from 2.8 to 13.8 for the person role.
Different sets of assumptions about causal relationships in role modeling research can be visually depicted using DAGs, which are then used to guide both statistical analysis and interpretation of results. Since study conclusions can be sensitive to different causal assumptions, results should be interpreted in the light of causal assumptions made in each study.
Children today are exposed to cell phones early in life, and may be at the greatest risk if exposure is harmful to health. We investigated associations between cell phone exposures and headaches in children.
The Danish National Birth Cohort enrolled pregnant women between 1996 and 2002. When their children reached age seven years, mothers completed a questionnaire regarding the child’s health, behaviors, and exposures. We used multivariable adjusted models to relate prenatal only, postnatal only, or both prenatal and postnatal cell phone exposure to whether the child had migraines and headache-related symptoms.
Our analyses included data from 52,680 children. Children with cell phone exposure had higher odds of migraines and headache-related symptoms than children with no exposure. The odds ratio for migraines was 1.30 (95% confidence interval: 1.01–1.68) and for headache-related symptoms was 1.32 (95% confidence interval: 1.23–1.40) for children with both prenatal and postnatal exposure.
In this study, cell phone exposures were associated with headaches in children, but the associations may not be causal given the potential for uncontrolled confounding and misclassification in observational studies such as this. However, given the widespread use of cell phones, if a causal effect exists it would have great public health impact.
Cellular phone; child; electromagnetic frequency; environmental exposure; migraine; mobile phone; pain; radiofrequency
In maintenance hemodialysis (HD) patients, overweight and obesity are associated with survival advantages. Given greater survival of minority maintenance HD patients, we hypothesized that elevated body mass index (BMI) is more strongly associated with lower mortality among Blacks and Hispanics relative to non-Hispanic whites.
Retrospective, cohort study.
Setting and participants
We examined a 6 year (2001–2007) cohort of 109,605 maintenance HD patients including 39,090 Blacks, 17,417 Hispanics and 53,098 non-Hispanic white maintenance HD outpatients from DaVita dialysis clinics. Cox proportional hazards models examined the association between BMI and survival.
Race and BMI.
All cause mortality.
Patients were (mean±SD) 62±15 years old and included 45% women and 45% diabetics. Across 10 a priori selected BMI categories (<18 to ≥40 kg/m2) higher BMI was associated with greater survival in all 3 racial/ethnic groups. Hispanic and Black patients, however, experienced consistently higher survival gains compared to non-Hispanic Whites across almost all BMI categories. Hispanics in the ≥40 kg/m2 category had the lowest death hazard ratio (HR, 0.57; 95% confidence interval [CI], 0.49–0.68) compared to non-Hispanic Whites in the 21.5-<23 kg/m2 group (reference category). While the inverse association was observed for all subgroups, Black maintenance HD patients exhibited the largest decline in death HR with increasing BMI.
Race and ethnicity categories were based on self-identified data.
Whereas survival advantage of high BMI is consistent across all racial/ethnic groups, Black maintenance HD patients had the strongest association of high BMI with improved survival.
obesity; survival; hemodialysis; race; non-Hispanic white; Black; Hispanic
Multi-source feedback (MSF) offers doctors feedback on their performance from peers (medical colleagues), coworkers and patients. Researchers increasingly point to the fact that only a small majority of doctors (60–70 percent) benefit from MSF. Building on medical education and social psychology literature, the authors identified several factors that may influence change in response to MSF. Subsequently, they quantitatively studied the factors that advance the use of MSF for practice change.
This observational study was set in 26 non-academic hospitals in the Netherlands. In total, 458 specialists participated in the MSF program. Besides the collation of questionnaires, the Dutch MSF program is composed of a reflective portfolio and a facilitative interview aimed at increasing the acceptance and use of MSF. All specialists who finished a MSF procedure between May 2008 and September 2010 were invited to complete an evaluation form. The dependent variable was self-reported change. Three categories of independent variables (personal characteristics, experiences with the assessments and mean MSF ratings) were included in the analysis. Multivariate regression analysis techniques were used to identify the relation between the independent variables and specialists’ reported change in actual practice.
In total, 238 medical specialists (response rate 52 percent) returned an evaluation form and participated in the study. A small majority (55 percent) of specialists reported to have changed their professional performance in one or more aspects in response to MSF. Regression analyses revealed that two variables had the most effect on reported change. Perceived quality of mentoring positively influenced reported change (regression coefficient beta = 0.527, p < 0.05) as did negative scores offered by colleagues. (regression coefficient beta = −0.157, p < 0.05). The explained variance of these two variables combined was 34 percent.
Perceived quality of mentoring and MSF ratings from colleagues seem to be the main motivators for the self-reported change in response to MSF by specialists. These insights could leverage in increasing the use of MSF for practice change by investing in the quality of mentors.
Performance assessment; Mentoring; Multisource feedback; Physicians; Continuous medical education
Residents are vital to the clinical workforce of today and tomorrow. Although in training to become specialists, they also provide much of the daily patient care. Residency training aims to prepare residents to provide a high quality of care. It is essential to assess the patient outcome aspects of residency training, to evaluate the effect or impact of global investments made in training programs. Therefore, we conducted a systematic review to evaluate the effects of relevant aspects of residency training on patient outcomes.
The literature was searched from December 2004 to February 2011 using MEDLINE, Cochrane, Embase and the Education Resources Information Center databases with terms related to residency training and (post) graduate medical education and patient outcomes, including mortality, morbidity, complications, length of stay and patient satisfaction. Included studies evaluated the impact of residency training on patient outcomes.
Ninety-seven articles were included from 182 full-text articles of the initial 2,001 hits. All studies were of average or good quality and the majority had an observational study design.
Ninety-six studies provided insight into the effect of 'the level of experience of residents' on patient outcomes during residency training. Within these studies, the start of the academic year was not without risk (five out of 19 studies), but individual progression of residents (seven studies) as well as progression through residency training (nine out of 10 studies) had a positive effect on patient outcomes. Compared with faculty, residents' care resulted mostly in similar patient outcomes when dedicated supervision and additional operation time were arranged for (34 out of 43 studies). After new, modified or improved training programs, patient outcomes remained unchanged or improved (16 out of 17 studies). Only one study focused on physicians' prior training site when assessing the quality of patient care. In this study, training programs were ranked by complication rates of their graduates, thus linking patient outcomes back to where physicians were trained.
The majority of studies included in this systematic review drew attention to the fact that patient care appears safe and of equal quality when delivered by residents. A minority of results pointed to some negative patient outcomes from the involvement of residents. Adequate supervision, room for extra operation time, and evaluation of and attention to the individual competence of residents throughout residency training could positively serve patient outcomes. Limited evidence is available on the effect of residency training on later practice. Both qualitative and quantitative research designs are needed to clarify which aspects of residency training best prepare doctors to deliver high quality care.
There is a global need to assess physicians' professional performance in actual clinical practice. Valid and reliable instruments are necessary to support these efforts. This study focuses on the reliability and validity, the influences of some sociodemographic biasing factors, associations between self and other evaluations, and the number of evaluations needed for reliable assessment of a physician based on the three instruments used for the multisource assessment of physicians' professional performance in the Netherlands.
This observational validation study of three instruments underlying multisource feedback (MSF) was set in 26 non-academic hospitals in the Netherlands. In total, 146 hospital-based physicians took part in the study. Each physician's professional performance was assessed by peers (physician colleagues), co-workers (including nurses, secretary assistants and other healthcare professionals) and patients. Physicians also completed a self-evaluation. Ratings of 864 peers, 894 co-workers and 1960 patients on MSF were available. We used principal components analysis and methods of classical test theory to evaluate the factor structure, reliability and validity of instruments. We used Pearson's correlation coefficient and linear mixed models to address other objectives.
The peer, co-worker and patient instruments respectively had six factors, three factors and one factor with high internal consistencies (Cronbach's alpha 0.95 - 0.96). It appeared that only 2 percent of variance in the mean ratings could be attributed to biasing factors. Self-ratings were not correlated with peer, co-worker or patient ratings. However, ratings of peers, co-workers and patients were correlated. Five peer evaluations, five co-worker evaluations and 11 patient evaluations are required to achieve reliable results (reliability coefficient ≥ 0.70).
The study demonstrated that the three MSF instruments produced reliable and valid data for evaluating physicians' professional performance in the Netherlands. Scores from peers, co-workers and patients were not correlated with self-evaluations. Future research should examine improvement of performance when using MSF.
The development and use of performance indicators (PI) in the field of public mental health care (PMHC) has increased rapidly in the last decade. To gain insight in the current state of PI for PMHC in nations and regions around the world, we conducted a structured review of publications in scientific peer-reviewed journals supplemented by a systematic inventory of PI published in policy documents by (non-) governmental organizations.
Publications on PI for PMHC were identified through database- and internet searches. Final selection was based on review of the full content of the publications. Publications were ordered by nation or region and chronologically. Individual PI were classified by development method, assessment level, care domain, performance dimension, diagnostic focus, and data source. Finally, the evidence on feasibility, data reliability, and content-, criterion-, and construct validity of the PI was evaluated.
A total of 106 publications were included in the sample. The majority of the publications (n = 65) were peer-reviewed journal articles and 66 publications specifically dealt with performance of PMHC in the United States. The objectives of performance measurement vary widely from internal quality improvement to increasing transparency and accountability. The characteristics of 1480 unique PI were assessed. The majority of PI is based on stakeholder opinion, assesses care processes, is not specific to any diagnostic group, and utilizes administrative data sources. The targeted quality dimensions varied widely across and within nations depending on local professional or political definitions and interests. For all PI some evidence for the content validity and feasibility has been established. Data reliability, criterion- and construct validity have rarely been assessed. Only 18 publications on criterion validity were included. These show significant associations in the expected direction on the majority of PI, but mixed results on a noteworthy number of others.
PI have been developed for a broad range of care levels, domains, and quality dimensions of PMHC. To ensure their usefulness for the measurement of PMHC performance and advancement of transparency, accountability and quality improvement in PMHC, future research should focus on assessment of the psychometric properties of PI.
Previous studies identified different typologies of role models (as teacher/supervisor, physician and person) and explored which of faculty's characteristics could distinguish good role models. The aim of this study was to explore how and to which extent clinical faculty's teaching performance influences residents' evaluations of faculty's different role modelling statuses, especially across different specialties.
In a prospective multicenter multispecialty study of faculty's teaching performance, we used web-based questionnaires to gather empirical data from residents. The main outcome measures were the different typologies of role modelling. The predictors were faculty's overall teaching performance and faculty's teaching performance on specific domains of teaching. The data were analyzed using multilevel regression equations.
In total 219 (69% response rate) residents filled out 2111 questionnaires about 423 (96% response rate) faculty. Faculty's overall teaching performance influenced all role model typologies (OR: from 8.0 to 166.2). For the specific domains of teaching, overall, all three role model typologies were strongly associated with “professional attitude towards residents” (OR: 3.28 for teacher/supervisor, 2.72 for physician and 7.20 for the person role). Further, the teacher/supervisor role was strongly associated with “feedback” and “learning climate” (OR: 3.23 and 2.70). However, the associations of the specific domains of teaching with faculty's role modelling varied widely across specialties.
This study suggests that faculty can substantially enhance their role modelling by improving their teaching performance. The amount of influence that the specific domains of teaching have on role modelling differs across specialties.
Uncontrolled confounding in observational studies gives rise to biased effect estimates. Sensitivity analysis techniques can be useful in assessing the magnitude of these biases. In this paper, we use the potential outcomes framework to derive a general class of sensitivity-analysis formulas for outcomes, treatments, and measured and unmeasured confounding variables that may be categorical or continuous. We give results for additive, risk-ratio and odds-ratio scales. We show that these results encompass a number of more specific sensitivity-analysis methods in the statistics and epidemiology literature. The applicability, usefulness, and limits of the bias-adjustment formulas are discussed. We illustrate the sensitivity-analysis techniques that follow from our results by applying them to 3 different studies. The result bias formulas are particularly simple and easy to use in settings in which the unmeasured confounding variable is binary with constant effect on the outcome across treatment and covariate levels, and with a constant prevalence difference across covariate levels when comparing 2 treatment levels.
Tools for the evaluation, improvement and promotion of the teaching excellence of faculty remain elusive in residency settings. This study investigates (i) the reliability and validity of the data yielded by using two new instruments for evaluating the teaching qualities of medical faculty, (ii) the instruments' potential for differentiating between faculty, and (iii) the number of residents' evaluations needed per faculty to reliably use the instruments.
Methods and Materials
Multicenter cross-sectional survey among 546 residents and 629 medical faculty representing 29 medical (non-surgical) specialty training programs in the Netherlands. Two instruments—one completed by residents and one by faculty—for measuring teaching qualities of faculty were developed. Statistical analyses included factor analysis, reliability and validity exploration using standard psychometric methods, calculation of the numbers of residents' evaluations needed per faculty to achieve reliable assessments and variance components and threshold analyses.
A total of 403 (73.8%) residents completed 3575 evaluations of 570 medical faculty while 494 (78.5%) faculty self-evaluated. In both instruments five composite-scales of faculty teaching qualities were detected with high internal consistency and reliability: learning climate (Cronbach's alpha of 0.85 for residents' instrument, 0.71 for self-evaluation instrument, professional attitude and behavior (0.84/0.75), communication of goals (0.90/0.84), evaluation of residents (0.91/0.81), and feedback (0.91/0.85). Faculty tended to evaluate themselves higher than did the residents. Up to a third of the total variance in various teaching qualities can be attributed to between-faculty differences. Some seven residents' evaluations per faculty are needed for assessments to attain a reliability level of 0.90.
The instruments for evaluating teaching qualities of medical faculty appear to yield reliable and valid data. They are feasible for use in medical residencies, can detect between-faculty differences and supply potentially useful information for improving graduate medical education.
The importance of effective clinical teaching for the quality of future patient care is globally understood. Due to recent changes in graduate medical education, new tools are needed to provide faculty with reliable and individualized feedback on their teaching qualities. This study validates two instruments underlying the System for Evaluation of Teaching Qualities (SETQ) aimed at measuring and improving the teaching qualities of obstetrics and gynecology faculty.
Methods and Findings
This cross-sectional multi-center questionnaire study was set in seven general teaching hospitals and two academic medical centers in the Netherlands. Seventy-seven residents and 114 faculty were invited to complete the SETQ instruments in the duration of one month from September 2008 to September 2009. To assess reliability and validity of the instruments, we used exploratory factor analysis, inter-item correlation, reliability coefficient alpha and inter-scale correlations. We also compared composite scales from factor analysis to global ratings. Finally, the number of residents' evaluations needed per faculty for reliable assessments was calculated. A total of 613 evaluations were completed by 66 residents (85.7% response rate). 99 faculty (86.8% response rate) participated in self-evaluation. Factor analysis yielded five scales with high reliability (Cronbach's alpha for residents' and faculty): learning climate (0.86 and 0.75), professional attitude (0.89 and 0.81), communication of learning goals (0.89 and 0.82), evaluation of residents (0.87 and 0.79) and feedback (0.87 and 0.86). Item-total, inter-scale and scale-global rating correlation coefficients were significant (P<0.01). Four to six residents' evaluations are needed per faculty (reliability coefficient 0.60–0.80).
Both SETQ instruments were found reliable and valid for evaluating teaching qualities of obstetrics and gynecology faculty. Future research should examine improvement of teaching qualities when using SETQ.
Medical educational reform includes enhancing role modelling of clinical teachers. This requires faculty being aware of their role model status and performance. We developed the System for Evaluation of Teaching Qualities (SETQ) to generate individualized feedback on previously defined teaching qualities and role model status for faculty in (non) academic hospitals.
(i) To examine whether teaching qualities of faculty were associated with their being seen as a specialist role model by residents, and (ii) to investigate whether those associations differed across residency years and specialties.
Methods & Materials
Cross-sectional questionnaire survey amongst 549 Residents of 36 teaching programs in 15 hospitals in the Netherlands. The main outcome measure was faculty being seen as specialist role models by residents. Statistical analyses included (i) Pearson's correlation coefficients and (ii) multivariable logistic generalized estimating equations to assess the (adjusted) associations between each of five teaching qualities and ‘being seen as a role model’.
407 residents completed a total of 4123 evaluations of 662 faculty. All teaching qualities were positively correlated with ‘being seen as a role model’ with correlation coefficients ranging from 0.49 for ‘evaluation of residents’ to 0.64 for ‘learning climate’ (P<0.001). Faculty most likely to be seen as good role models were those rated highly on ‘feedback’ (odds ratio 2.91, 95% CI: 2.41–3.51), ‘a professional attitude towards residents’ (OR 2.70, 95% CI: 2.34–3.10) and ‘creating a positive learning climate’ (OR 2.45, 95% CI: 1.97–3.04). Results did not seem to vary much across residency years. The relative strength of associations between teaching qualities and being seen as a role model were more distinct when comparing specialties.
Good clinical educators are more likely to be seen as specialist role models for most residents.
Hospitals in European countries apply a wide range of quality improvement strategies. Knowledge of the effectiveness of these strategies, implemented as part of an overall hospital quality improvement system, is limited.
We propose to study the relationships among organisational quality improvement systems, patient empowerment, organisational culture, professionals' involvement with the quality of hospital care, including clinical effectiveness, patient safety and patient involvement. We will employ a cross-sectional, multi-level study design in which patient-level measurements are nested in hospital departments, which are in turn nested in hospitals in different EU countries. Mixed methods will be used for data collection, measurement and analysis. Hospital/care pathway level constructs that will be assessed include external pressure, hospital governance, quality improvement system, patient empowerment in quality improvement, organisational culture and professional involvement. These constructs will be assessed using questionnaires. Patient-level constructs include clinical effectiveness, patient safety and patient involvement, and will be assessed using audit of patient records, routine data and patient surveys. For the assessment of hospital and pathway level constructs we will collect data from randomly selected hospitals in eight countries. For a sample of hospitals in each country we will carry out additional data collection at patient-level related to four conditions (stroke, acute myocardial infarction, hip fracture and delivery). In addition, structural components of quality improvement systems will be assessed using visits by experienced external assessors. Data analysis will include descriptive statistics and graphical representations and methods for data reduction, classification techniques and psychometric analysis, before moving to bi-variate and multivariate analysis. The latter will be conducted at hospital and multilevel. In addition, we will apply sophisticated methodological elements such as the use of causal diagrams, outcome modelling, double robust estimation and detailed sensitivity analysis or multiple bias analyses to assess the impact of the various sources of bias.
Products of the project will include a catalogue of instruments and tools that can be used to build departmental or hospital quality and safety programme and an appraisal scheme to assess the maturity of the quality improvement system for use by hospitals and by purchasers to contract hospitals.
Information on prescribing quality is increasingly used by policy makers, insurance companies and health care providers. For reliable assessment of prescribing quality it is important to correctly identify the patients eligible for recommended treatment. Often either diagnostic codes or clinical measurements are used to identify such patients. We compared these two approaches regarding the outcome of the prescribing quality assessment and their ability to identify treated and undertreated patients.
The approaches were compared using electronic health records for 3214 diabetes patients from 70 general practitioners. We selected three existing prescribing quality indicators (PQI) assessing different aspects of treatment in patients with hypertension or who were overweight. We compared population level prescribing quality scores and proportions of identified patients using definitions of hypertension or being overweight based on diagnostic codes, clinical measurements or both.
The prescribing quality score for prescribing any antihypertensive treatment was 93% (95% confidence interval 90-95%) using the diagnostic code-based approach, and 81% (78-83%) using the measurement-based approach. Patients receiving antihypertensive treatment had a better registration of their diagnosis compared to hypertensive patients in whom such treatment was not initiated. Scores on the other two PQI were similar for the different approaches, ranging from 64 to 66%. For all PQI, the clinical measurement -based approach identified higher proportions of both well treated and undertreated patients compared to the diagnostic code -based approach.
The use of clinical measurements is recommended when PQI are used to identify undertreated patients. Using diagnostic codes or clinical measurement values has little impact on the outcomes of proportion-based PQI when both numerator and denominator are equally affected. In situations when a diagnosis is better registered for treated than untreated patients, as we observed for hypertension, the diagnostic code-based approach results in overestimation of provided treatment.
The relationship between individual and population health is partially built on the broad dichotomization of medicine into clinical medicine and public health. Potential drawbacks of current views include seeing both individual and population health as absolute and independent concepts. I will argue that the relationship between individual and population health is largely relative and dynamic. Their interrelated dynamism derives from a causally defined life course perspective on health determination starting from an individual’s conception through growth, development and participation in the collective till death, all seen within the context of an adaptive society. Indeed, it will become clear that neither individual nor population health is identifiable or even definable without informative contextualization within the other. For instance, a person’s health cannot be seen in isolation but must be placed in the rich contextual web such as the socioeconomic circumstances and other health determinants of where they were conceived, born, bred, and how they shaped and were shaped by their environment and communities, especially given the prevailing population health exposures over their lifetime. We cannot discuss the “what” and “how much” of individual and population health until we know the cumulative trajectories of both, using appropriate causal language.
Causality; Context; Ethics; Individual health; Life course; Population health; Theory of health
Patterns in time, place and cause of death can have an important impact on calculated hospital mortality rates. Objective is to quantify these patterns following myocardial infarction and stroke admissions in Dutch hospitals during the period 1996–2003, and to compare trends in the commonly used 30-day in-hospital mortality rates with other types of mortality rates which use more extensive follow-up in time and place of death.
Discharge data for all Dutch admissions for index conditions (1996–2003) were linked to the death certification registry. Then, mortality rates within the first 30, 90 and 365 days following admissions were analyzed for deaths occurring within and outside hospitals.
Most deaths within a year after admission occurred within 30 days (60–70%). No significant trends in this distribution of deaths over time were observed. Significant trends in the distribution over place of death were observed for both conditions. For myocardial infarction, the proportion of deaths after transfer to another hospital has doubled from 1996–2003. For stroke a significant rise of the proportion of deaths outside hospital was found. For MI the proportion of deaths attributed to a circulatory disease has significantly fallen ovtime. Seven types of hospital mortality indicators, different in scope and observation period, all show a drop of hospital mortality for both MI and stroke over the period 1996–2003. For stroke the observed absolute reduction in death rate increases for the first year after admission, for MI the observed drop in 365-day overall mortality almost equals the observed drop in 30-day in hospital mortality over 1996–2003.
Changes in the timing, place and causes of death following admissions for myocardial infarction and stroke have important implications for the definitions of in-hospital and post-admission mortality rates as measures of hospital performance. Although necessary for understanding mortality patterns over time, including within mortality rates deaths which occur outside hospitals and after longer periods following index admissions remain debatable and may not reflect actual hospital performance but probably mirrors transfer, efficiency, and other health care policies.
Tu et al present an analysis of the equivalence of three paradoxes, namely, Simpson's, Lord's, and the suppression phenomena. They conclude that all three simply reiterate the occurrence of a change in the association of any two variables when a third variable is statistically controlled for. This is not surprising because reversal or change in magnitude is common in conditional analysis. At the heart of the phenomenon of change in magnitude, with or without reversal of effect estimate, is the question of which to use: the unadjusted (combined table) or adjusted (sub-table) estimate. Hence, Simpson's paradox and related phenomena are a problem of covariate selection and adjustment (when to adjust or not) in the causal analysis of non-experimental data. It cannot be overemphasized that although these paradoxes reveal the perils of using statistical criteria to guide causal analysis, they hold neither the explanations of the phenomenon they depict nor the pointers on how to avoid them. The explanations and solutions lie in causal reasoning which relies on background knowledge, not statistical criteria.
To assess the reliability and validity of a translated version of the American Hospital-level Consumer Assessment of Health Plans Survey® (H-CAHPS) instrument for use in Dutch health care.
Data Sources/Study Setting
Primary survey data from adults aged 18 years or more who were recently discharged from two multispecialty city hospitals in the Netherlands.
We used forward and backward translation procedures and a panel of experts to adapt the 66-item pilot H-CAHPS into a 70-item Dutch instrument. Descriptive statistics and standard psychometric methods were then used to test the reliability and validity of the new instrument.
From late November 2003 to early January 2004, the survey was administered by mail to 1,996 patients discharged within the previous 2 months.
Analyses supported the reliability and validity of the following 7-factor H-CAHPS structure for use in Dutch hospitals: on doctor's communication, nurses' communication, discharge information, communication about medication, pain control, physical environment of hospital, and nursing services. The internal consistency reliability of the scales ranged from 0.60 to 0.88. Items related to “family receiving help when on visit,” “hospital staff introducing self,” and “admission delays” did not improve the psychometric properties of the new instrument.
These findings suggest that the H-CAHPS instrument is reliable and valid for use in the Dutch context. However, more research will be needed to support its equivalence to the United States version, and its use for between-hospital comparisons.
CAHPS®; hospitals; Dutch health care; patient experiences of care; cross-cultural translation
Physician migration from poor to rich countries is considered an important contributor to the growing health workforce crisis in the developing world. This is particularly true for Africa. The perceived magnitude of such migration for each source country might, however, depend on the choice of metrics used in the analysis. This study examined the influence of choice of migration metrics on the rankings of African countries that suffered the most physician migration, and investigated the correlates of physician migration.
Ranking and correlational analyses were conducted on African physician migration data adjusted for bilateral net flows, and supplemented with developmental, economic and health system data. The setting was the 53 African birth countries of African-born physicians working in nine wealthier destination countries. Three metrics of physician migration were used: total number of physician émigrés; emigration fraction defined as the proportion of the potential physician pool working in destination countries; and physician migration density defined as the number of physician émigrés per 1000 population of the African source country.
Rankings based on any of the migration metrics differed substantially from those based on the other two metrics. Although the emigration fraction and physician migration density metrics gave proportionality to the migration crisis, only the latter was consistently associated with source countries' workforce capacity, health, health spending, economic and development characteristics. As such, higher physician migration density was seen among African countries with relatively higher health workforce capacity (0.401 ≤ r ≤ 0.694, p ≤ 0.011), health status, health spending, and development.
The perceived magnitude of physician migration is sensitive to the choice of metrics. Complementing the emigration fraction, the physician migration density is a metric which gives a different but proportionate picture of which African countries stand to lose relatively more of its physicians with unchecked migration. The nature of health policies geared at health-worker migration can be expected to depend on the choice of migration metrics.
Given the proliferation and the growing complexity of performance measurement initiatives in many health systems, the Netherlands and Ontario, Canada expressed interests in cross-national comparisons in an effort to promote knowledge transfer and best practise. To support this cross-national learning, a study was undertaken to compare health system performance approaches in The Netherlands with Ontario, Canada.
We explored the performance assessment framework and system of each constituency, the embeddedness of performance data in management and policy processes, and the interrelationships between the frameworks. Methods used included analysing governmental strategic planning and policy documents, literature and internet searches, comparative descriptive tables, and schematics. Data collection and analysis took place in Ontario and The Netherlands. A workshop to validate and discuss the findings was conducted in Toronto, adding important insights to the study.
Both Ontario and The Netherlands conceive health system performance within supportive frameworks. However they differ in their assessment approaches. Ontario's Scorecard links performance measurement with strategy, aimed at health system integration. The Dutch Health Care Performance Report (Zorgbalans) does not explicitly link performance with strategy, and focuses on the technical quality of healthcare by measuring dimensions of quality, access, and cost against healthcare needs. A backbone 'five diamond' framework maps both frameworks and articulates the interrelations and overlap between their goals, themes, dimensions and indicators. The workshop yielded more contextual insights and further validated the comparative values of each constituency's performance assessment system.
To compare the health system performance approaches between The Netherlands and Ontario, Canada, several important conceptual and contextual issues must be addressed, before even attempting any future content comparisons and benchmarking. Such issues would lend relevant interpretational credibility to international comparative assessments of the two health systems.
Few studies have tried to assess the combined cross-sectional and temporal contributions of a more comprehensive set of amenable factors to population health outcomes for wealthy countries during the last 30 years of the 20th century. We assessed the overall ecological associations between mortality and factors amenable to public health. These amenable factors included addictive and nutritional lifestyle, air quality, public health spending, healthcare coverage, and immunizations.
We used a pooled cross-sectional, time series analysis with corrected fixed effects regression models in an ecological design involving eighteen member countries of the Organisation for Economic Cooperation and Development during the period 1970 to 1999.
Alcohol, tobacco, and fat consumption, and sometimes, air pollution were significantly associated with higher all-cause mortality and premature death. Immunizations, health care coverage, fruit/vegetable and protein consumption, and collective health expenditure had negative effects on mortality and premature death, even after controlling for the elderly, density of practicing physicians, doctor visits and per capita GDP. However, tobacco, air pollution, and fruit/vegetable intake were sometimes sensitive to adjustments.
Mortality and premature deaths could be improved by focusing on factors that are amenable to public health policies. Tackling these issues should be reflected in the ongoing assessments of health system performance.