Development of a weighted scale to assess the quality of cost-effectiveness studies and an application to the economic evaluations of tetravalent HPV vaccine

Aim: Interest in the quality of economic analyses is increasing in the field of decision-making. Drummond's checklist is a useful tool. This study aimed to use a weighted version of Drummond’s checklist together with a consensus of experts to derive a new scoring system to improve the evaluation of economic analyses of tetravalent human papillomavirus (HPV) vaccine as a case study. Methods: Drummond's checklist is composed of 35 items divided into 3 sections: study design, data collection and analysis and interpretation of results. To weight the items, a group of experts was asked to attribute a score according to their importance. A bibliographic search of economic evaluations of tetravalent HPV vaccine was performed. Two researchers assessed the quality of selected studies according to the original and weighted checklist. Results: The weighted scores assigned by the consensus to study design, data collection and analysis and interpretation of results were 26, 45 and 48, respectively. Thirteen papers were included in the review of economic evaluations of tetravalent HPV vaccine. According to the weighted Drummond's checklist, their median quality score was 74 with a maximum of 119. The highest score was reached in the study design section. Conclusion: According to the weighted Drummond's checklist, studies were judged to be of medium quality. The main pitfalls were found in issues assigned the highest scores by the consensus, underlying the utility of weighting available checklists to improve the estimate of the quality of economic analyses. The weighted checklist could be thus proposed as a scoring tool to assess the quality.