- Framework of problems / Rigorous
- Weaknesses identified in some Cochrane reviews
- The normality assumption on between-study random effects was questionable in a considerable number of Cochrane meta-analyses
| Ref ID | 885 |
| First Author | Z. Liu |
| Journal | BMC MEDICINE |
| Year Of Publishing | 2023 |
| URL | https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-023-02823-9 |
| Keywords |
• General medical • Heterogeneity • Cochrane • Statistical |
| Problem(s) |
• Inadequate analysis of heterogeneity • Weaknesses identified in some Cochrane reviews |
| Number of systematic reviews included | 5652 |
| Summary of Findings | From 7667 Cochrane meta-analyses from 5652 overarching Cochrane systematic reviews. The between-study normality assumption was commonly violated in Cochrane meta-analyses. Based on 4234 eligible meta-analyses with binary outcomes and 3433 with non-binary outcomes, the proportion of meta-analyses that had statistically significant non-normality varied from 15.1 to 26.2%. Risk differences and non-binary outcomes led to more frequent non-normality issues than odds ratios and risk ratios. For binary outcomes, the between-study non-normality was more frequently found in meta-analyses with larger sample sizes and event rates away from 0 and 100%. |
| Did the article find that the problem(s) led to qualitative changes in interpretation of the results? | N/A |
| Are the methods of the article described in enough detail to replicate the study? | No |