Matching-Adjusted Indirect Comparison Studies in Oncology: A Scoping Review Focused on Reporting Quality

Matching-adjusted indirect comparisons (MAICs) can be used in case of cross-trial heterogeneity or availability of only single-arm trials. Although the National Institute for Health and Care Excellence (NICE) provides MAIC-development orientation, many still do not adhere to it. Our goal was to map MAIC oncology studies and whether NICE recommendations were observed.

We included MAIC studies comparing treatments in oncology from 2010. We searched PubMed, Embase, and the Cochrane Library up to October 1, 2024. We analyzed MAIC characteristics such as previous systematic reviews, whether the analysis was anchored or unanchored, selection of variables, and individual patient data (IPD) reporting. We adopted NICE recommendations for the assessment of MAIC studies.

We included 117 MAIC studies, which often explored multiple myeloma (n = 19%) and non-small cell lung cancer (17%) more frequently. Most MAICs were unanchored (72%), with an average of 1.9 comparisons per study. MAIC studies generally reported using pseudo-IPD (69%) but did not report the source of IPD (78%). In general, MAICs did not conduct systematic reviews to select trials for inclusion (66%). The average sample size reduction, in comparison with the original trials, was 44.9%. Only 3 MAICs fulfilled all NICE recommendations. The least reported aspects were the adjustment for all effect modifiers and prognostic variables (for unanchored MAICs), evidence of effect modifier status, and distribution of weights.

Most MAIC models did not follow NICE recommendations. Our review highlights the importance of rigorous methodological standards and thorough reporting of MAIC studies to enhance their credibility.