OBJECTIVES: Meta-analysis (MA) of economic evaluation (EE) studies is a novel method to quantitatively summarize economic evidence. This study provides a step-by-step description of the methods for EE study data harmonization and synthesis and a framework for handling study heterogeneity using pneumococcal conjugate vaccines (10-valent pneumococcal conjugate vaccine [PCV10] and 13-valent pneumococcal conjugate vaccine [PCV13]) in children as a case study.

METHODS: Data harmonization methods were constructed to account for variability in data availability, economic parameters, and heterogeneity of EE studies (i.e., country income level, currency, time horizon, perspective, modelling approach, and willingness to pay). We developed five data extraction scenarios based on the availability of data reported in studies, including the incremental cost (ΔC), incremental effectiveness (ΔE), and incremental cost-effectiveness ratio (ICER), and their associated dispersion. The incremental net benefit (INB) and variance were estimated and pooled across studies using a random-effects model for MA.

RESULTS: A total of 67 studies with 150 comparisons were eligible for INB pooling. PCV13 was significantly cost-effective compared to PCV10, with an INB (95% confidence interval) of 74.06 (55.60, 92.52) and 67.57 (16.30, 118.85) from the payer and societal perspective, respectively, when including herd effects. From the payer perspective, PCV13 was significantly cost-effective compared to no vaccination, with INBs of 320.86 (265.58, 376.15) and 127.84 (21.24, 234.43) with and without herd effects, respectively. Meanwhile, PCV10 was only significantly cost-effective with an INB of 176.36 (68.91, 283.80) in the payer perspective when herd effects were considered. MA results were influenced by model assumptions, such as the inclusion of herd effects provided by PCVs.

CONCLUSIONS: Following the data harmonization approach, our case study demonstrates that the MA technique for summarizing PCV EE studies is a useful methodology for the synthesis of economic evidence to aid policy makers in decision-making.