Zeitschrift für Evidenz, Fortbildung und Qualität im Gesundheitswesen
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Z Evid Fortbild Qual Gesundhwes · Jan 2014
[GRADE guidelines: 13. Preparing Summary of Findings tables and evidence profiles - continuous outcomes].
Presenting continuous outcomes in Summary of Findings tables presents particular challenges to interpretation. When each study uses the same outcome measure, and the units of that measure are intuitively interpretable (e.g., duration of hospitalisation, duration of symptoms), presenting differences in means is usually desirable. When the natural units of the outcome measure are not easily interpretable, choosing a threshold to create a binary outcome and presenting relative and absolute effects become a more attractive alternative. When studies use different measures of the same construct, calculating summary measures requires converting to the same units of measurement for each study. The longest standing and most widely used approach is to divide the difference in means in each study by its standard deviation and present pooled results in standard deviation units (standardised mean difference). Disadvantages of this approach include vulnerability to varying degrees of heterogeneity in the underlying populations and difficulties in interpretation. Alternatives include presenting results in the units of the most popular or interpretable measure, converting to dichotomous measures and presenting relative and absolute effects, presenting the ratio of the means of intervention and control groups, and presenting the results in minimally important difference units. We outline the merits and limitations of each alternative and provide guidance for meta-analysts and guideline developers. ⋯ Summary of Findings tables provide succinct presentations of evidence quality and magnitude of effects. Summarising the findings of continuous outcomes presents special challenges to interpretation that become daunting when individual trials use different measures for the same construct. The most commonly used approach to providing pooled estimates for different measures, presenting results in standard deviation units, has limitations related to both statistical properties and interpretability. Potentially preferable alternatives include presenting results in the natural units of the most popular measure, transforming into a binary outcome and presenting relative and absolute effects, presenting the ratio of the means of intervention and control groups, and presenting results in preestablished minimally important difference units.
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Z Evid Fortbild Qual Gesundhwes · Jan 2014
Comparative Study[Comorbidity in medical guidelines: comparison of the current state, epidemiologic models and expert opinion].
Medical guidelines focusing on monomorbidities can be associated with adverse events in multimorbid patients. This study investigates how comorbidities are actually particularised in a set of German guidelines. In addition, it evaluates whether two epidemiologic approaches (disease combinations or clusters of comorbidities) can be used to systematically integrate multimorbidity in guideline development. ⋯ Methodological support is needed for addressing comorbidities in guidelines in a more consistent way. The currently existing epidemiologic approaches should not be used in their current form without being further developed and re-evaluated. Expert opinion of physicians involved in the care of multimorbid patients should be systematically included in methodological refinement studies.
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Z Evid Fortbild Qual Gesundhwes · Jan 2014
[Experiences with synopses of clinical guidelines using the example of synopses for Disease Management Programmes (DMP)].
Guideline synopses, i.e. the systematic synthesis of clinical practice guidelines, are used as a basis for Disease Management Programmes (DMPs) in Germany. One of the responsibilities of the German Institute for Quality and Efficiency in Health Care (IQWiG) is the preparation of guideline synopses for DMPs. The article describes the experiences with this methodology. ⋯ A guideline synopsis is an established tool for identifying health care standards as a basis for developing and updating DMPs. Further methodological development, particularly in collaboration with guideline providers, appears to be reasonable. It should be examined whether guideline synopses are suitable not only for guideline and DMP development, but also for other health care issues.
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The American Board of Internal Medicine (ABIM) Foundation launched the Choosing Wisely campaign in 2012 and until today convinced more than 50 US specialist societies to develop lists of interventions that may not improve people's health but are potentially harmful. We suggest combining these new efforts with the already existing efforts in clinical practice guideline development. Existing clinical practice guidelines facilitate a more participatory and evidence-based approach to the development of top 5 lists. In return, adding top 5 lists (for overuse and underuse) to existing clinical practice guidelines nicely addresses a neglected dimension to clinical practice guideline development, namely explicit information on which Do or Don't do recommendations are frequently disregarded in practice.