Unlike randomized controlled trials, lack of methodological rigor is a concern about real-world evidence (RWE) studies. The objective of this study was to characterize methodological practices of studies collecting pharmacoeconomic data in a real-world setting for the management of type 2 diabetes mellitus (T2DM).

A systematic literature review was performed using the PICO framework: population consisted of T2DM patients, interventions and comparators were any intervention for T2DM care or absence of intervention, and outcomes were resource utilization, productivity loss or utility. Only RWE studies were included, defined as studies that were not clinical trials and that collected de novo data (no retrospective analysis).

The literature search identified 1,158 potentially relevant studies, among which sixty were included in the literature review. Many studies showed a lack of transparency by not mentioning the source for outcome and exposure measurement, source for patient selection, number of study sites, recruitment duration, sample size calculation, sampling method, missing data, approbation by an ethics committee, obtaining patient's consent, conflicts of interest, and funding. A significant proportion of studies had poor quality scores and was at high risk of bias.

RWE from T2DM studies lacks transparency and credibility. There is a need for good procedural practices that can increase confidence in RWE studies. Standardized methodologies specifically adapted for RWE studies collecting pharmacoeconomic data for the management of T2DM could help future reimbursement decision making in this major public health problem.