A comparison of individual patient analysis versus pooled study meta-analysis methodologies of exercise training trials in heart failure patients

Background: A fixed effects meta-analysis of ten exercise training in trials heart failure patients was conducted. The aim of this current work was to compare different approaches to meta-analysis using the same dataset from the previous work on ten exercise training trials in heart failure patients. Methods: The following different meta-analysis techniques were used to analyse the data and compared the effects of exercise training on BNP, NT pro-BNP and peak VO2 before and after exercise training: (1) Trial level (traditional) level MA i) Follow up (post-exercise training intervention) outcome only. ii) Baseline-follow up difference (2) Patient level MA by Post-Stage ANCOVA i)naive model does not take into account trial level ii) Single Stage iii) Two Stage (3) Post outcome only i) Single stage ii) Pre-post outcome difference Single stage Results: The Individual patient data (IPD) analyses produced smaller effect sizes and 95% confidence intervals compared to conventional meta analysis. The advantage of the one-stage model is that it allows sub-group analyses, while the two-stage model is considered more robust but limited for sub-analyses. Conclusions: Our recommendation is to use one-stage or two-stage ANCOVA analysis, the former allows sub-group analysis, while the latter is considered to be more technically robust.