[Systematic Reviews on the Effectiveness of Multidisciplinary Rehabilitation].

Systematic reviews and meta-analyses of clinical trials are considered to represent the highest level of scientific evidence in clinical medicine provided internationally accepted guidelines and checklists are followed.In systematic reviews and meta-analyses all clinical studies focussing a specific predefined clinical question are collected and evaluated. The results of systematic reviews strongly depend on the study protocol, including the exact definition of the population of interest, the therapeutic intervention under consideration and, last not least, the time period of observation. Moreover, evaluating multidisciplinary rehabilitation, its specifications with regard to therapeutic content, intensity and duration, supervision and general framework must be considered for correctly estimating determinants that control therapeutic success or failure.The range of potential risks of bias arising during planning, realization and publication of clinical studies is considerable and needs to be carefully estimated with regard to each single study included in meta-analysis.Taking together, the incremental scientific value of systematic reviews and meta-analyses cannot be taken for granted, but strongly depends on the methodological quality of the clinical studies being included as well as on the systematic process of the meta-analysis and the critical interpretation of the results.