Article type
Year
Abstract
Background: Systematic reviews and meta-analyses are the gold standard to assess efficacy and acceptability of treatments. In the field of antidepressant trials, hundreds of studies are available and many systematic reviews have been carried out so far, sometimes with conflicting results. It is known that the quality of the reviews may play an important role. However, this issue has not been yet systematically investigated.
Objectives: To examine the quality of meta-analyses of serotonin reuptake inhibitor treatment of depression and to shed light on the influence of methodological aspects on the results of these meta-analyses.
Methods: A comprehensive literature search for systematic reviews including meta-analysis of RCTs on SSRI and SNRI treatment in major depression was conducted. Studies comparing SSRI and SNRI to placebo or all kinds of pharmacological antidepressant treatments were included. Results were screened for inclusion or exclusion by two independent investigators. Relevant data was extracted from the included studies, and quality assessment of systematic reviews was performed. Influence of a variety of factors on the results of reviews was analysed by regression analyses and t-tests.
Results: The analyses included 134 reviews. Depending on the rating scale, the average quality of included studies was moderate or good, with a significant increase of study quality over the past 20 years. Blinding of reviews regarding authors and results had no impact on quality ratings. The results pointed out that there is room for improvement of current quality measurements for systematic reviews. Only involvement of drug companies in the publication of meta-analyses showed an impact on the effects of the review. All other factors tested failed to reveal statistically significant relationships with the results of the review.
Objectives: To examine the quality of meta-analyses of serotonin reuptake inhibitor treatment of depression and to shed light on the influence of methodological aspects on the results of these meta-analyses.
Methods: A comprehensive literature search for systematic reviews including meta-analysis of RCTs on SSRI and SNRI treatment in major depression was conducted. Studies comparing SSRI and SNRI to placebo or all kinds of pharmacological antidepressant treatments were included. Results were screened for inclusion or exclusion by two independent investigators. Relevant data was extracted from the included studies, and quality assessment of systematic reviews was performed. Influence of a variety of factors on the results of reviews was analysed by regression analyses and t-tests.
Results: The analyses included 134 reviews. Depending on the rating scale, the average quality of included studies was moderate or good, with a significant increase of study quality over the past 20 years. Blinding of reviews regarding authors and results had no impact on quality ratings. The results pointed out that there is room for improvement of current quality measurements for systematic reviews. Only involvement of drug companies in the publication of meta-analyses showed an impact on the effects of the review. All other factors tested failed to reveal statistically significant relationships with the results of the review.