Adherence to the iDSI reference case among published cost-per-DALY averted studies

Background: The iDSI reference case, originally published in 2014, aims to improve the quality and comparability of cost-effectiveness analyses (CEAs). This study assesses whether the development of the guideline has improved the reporting and methodology for CEAs using disability-adjusted life-years (DALYs). Methods: We analyzed the Tufts Medical Center Global Health CEA Registry to identify cost-per-DALY averted studies published from 2011 to 2017. Among each of 11 principles in the iDSI reference case, we translated all reporting standards and methodological specifications into quantifiable yes/no questions and awarded articles one point for each item satisfied. We then separately calculated reporting and methods scores, measured as percent adherence (0%=no adherence, 100%=full adherence). Using the year 2014 as the dissemination period, we conducted a pre-post analysis. Additionally, we conducted an analysis stratified by the 11 principles and examined different scoring strategies and dissemination periods in sensitivity analyses. Results: Articles averaged 74% adherence to reporting standards and 60% adherence to methodological specifications. Adherence to reporting standards increased slightly over time (72% pre-2014 vs. 75% post-2014, p<0.01), but methodological adherence did not significantly improve (59% pre-2014 vs. 60% post-2014, p=0.53). Overall, reporting adherence scores exceeded methodology adherence scores (74% vs. 60%, p<0.001). Articles seldom addressed budget impact (9% reporting, 10% methodology) or equity (7% reporting, 7% methodology). Conclusions: The iDSI reference case has substantial potential to serve as a useful resource for researchers and policy-makers in global health settings, but greater effort to promote adherence and awareness is needed to achieve its potential.