Problems of meta-analysis to explore rare diseases

Core Tip

Core Tip: Meta-analysis is essential in evidence-based medicine but presents challenges in rare diseases due to limited studies, small sample sizes, and reliance on observational data. These factors reduce statistical power, increase bias, and limit generalizability. Heterogeneity in patient characteristics and study design further complicates analysis, while traditional statistical methods may yield unreliable estimates. Collaborative networks, disease registries, and advanced techniques like Bayesian methods or the Hartung-Knapp-Sidik-Jonkman approach can help address these limitations. In some cases, scoping reviews may be more appropriate. Recognizing and managing these challenges is crucial to improving evidence quality and clinical outcomes in rare disease research.