Trust, but verify. The errors and misinterpretations in the Cochrane analysis by O. J. Storebo and colleagues on the efficacy and safety of methylphenidate for the treatment of children and adolescents with ADHD

Ref ID 267
First Author T. Banaschewski
Journal ZEITSCHRIFT FUR KINDER-UND JUGENDPSYCHIATRIE UND PSYCHOTHERAPIE
Year Of Publishing 2016
URL https://econtent.hogrefe.com/doi/pdf/10.1024/1422-4917/a000433
Keywords • Cochrane
• Pharmacological
• Paediatrics
• Risk of bias
• Heterogeneity
• Error
Problem(s) • Weaknesses identified in some Cochrane reviews
• Flawed risk of bias undertaken
• Inadequate analysis of heterogeneity
• Errors in effect estimate calculations or data synthesis
• Failure to define clinically meaningful outcomes
Article Type Non-systematic literature review
First Author Country Germany
Aim To highlight various examples of errors, inconsistencies, and misinterpretations in a Cochrane systematic review on the efficacy and safety of methylphenidate for the treatment of children and adolescents with ADHD which reportedly led to false results and inadequate conclusions.
Level of Investigation Descriptive
Summary of Findings The authors highlight that within a Cochrane systematic review on the efficacy and safety of methylphenidate for the treatment of children and adolescents with ADHD, the study selection was flawed and undertaken without sufficient scientific justification. It is concluded that due to flaw in meta-analysis and the heterogenous trial designs, the effect sizes were calculated as too small and, moreover, were inadmissibly clinically interpreted. The methodology of the assessment of bias and quality is not objective and cannot be substantiated by the data. The conclusion of the authors is stated to be grossly misleading.
Number of systematic reviews included 1
Number of eligible systematic reviews assessed 1
Treatment impacted Yes
Treatment impacted description The authors state that 4 of the 19 studies used to calculate the effect size should not have been entered into the analysis: In these studies, methylphenidate was not tested against placebo, but rather a combined treatment with another intervention and MPH was tested against this intervention alone.
Interpretation impacted Yes
Interpretation impacted description The authors assert that the corrected effect size lies at 0.89 (95 % confidence interval 0.79–1.01) as opposed to 0.77 (95 % confi dence interval 0.90– 0.64) which implies a large effect size rather than moderate.