Reporting Bias Prevalence in Systematic Reviews and Meta-analyses on Trochleoplasty: A Systematic Review

Abstracts of systematic reviews and meta-analyses offer an efficient way to digest the full text, however; abstracts that contain spin, defined as reporting greater efficacy or safety of the experimental treatment than is supported by the results, can negatively affect clinical decisions.

The purpose of this study was to identify and analyze the incidence and types of spin present in systematic reviews and meta-analyses of trochleoplasty procedures while also determining if any identifiable patterns of spin exist. It was hypothesized that abstracts of systematic reviews and meta-analyses on trochleoplasty would contain spin elements.

Systematic review; Level of evidence, 4.

This study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Peer-reviewed articles were collected from the PubMed, Scopus, Web of Science, and Google Scholar databases as of January 2025. Inclusion criteria were systematic reviews or meta-analyses assessing trochleoplasty. Quality was assessed using AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews Version 2). Two independent authors examined the incidence of the 15 most severe categories of spin. The Fisher exact test with a 95% confidence interval was used to examine associations between spin type and various study characteristics.

Twenty studies met inclusion criteria, and 9 were meta-analyses. All studies contained at least 1 type of spin (median, 1; range, 1-5). There were no significant associations between spin type or study characteristics, including PRISMA adherence. The most common type of spin was type 5 (conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies), which was observed in 10 (50.0%) articles.

Reporting bias is highly prevalent in many abstracts of systematic reviews and meta-analyses on trochleoplasty. When present, spin in the abstracts of the reviewed studies inappropriately favored safety, beneficial effects, and efficacy of the experimental treatment. These findings emphasize the need for clinicians to assess full-text articles regarding trochleoplasty as results presented in abstracts may frequently be misleading. The authors recommend the addition of spin bias evaluation to the PRISMA abstract checklist to help authors recognize and avoid spin in future abstracts of systematic reviews and meta-analyses.