Objectives: To systematically review the Willingness-to-Pay (WTP) threshold used in Greek cost-effectiveness (CE) studies over the last 10 years and investigate the methodology behind it.
Methods: A systematic search of PubMed and ScienceDirect was conducted up to May 2019. The identified studies were independently reviewed by two investigators against pre-determined inclusion and exclusion criteria. The data of selected studies were extracted using a relevant form and consequently were synthesized. Qualitative variables were presented with relative frequencies (%) and quantitative variables with median and interquartile range (IQR). Mann-Whitney and Kruskal Wallis tests were performed where needed.
Results: From the 221 identified studies, 102 satisfied the inclusion criteria. Studies were categorized to oncology (26.5%) and a non-oncology related (73.5%) based on drug treatment. The WTP threshold was reported to 71.6% of the studies (oncology: 59.3%; non-oncology: 76%), whereas the most frequently reported outcome associated with threshold was the “per quality-adjusted life year (QALY) gained” (oncology: 87.5%; non-oncology: 91.2%). A total of 34.3% of the studies with a reported threshold did not specified (NS) the origin of the threshold (oncology: 18.8%; non-oncology: 38.6%). From the rest of studies, the vast majority (91.7%) adopted thresholds equal to one-to-three times the gross domestic product (GDP) per capita [oncology: 100%; non-oncology: 88.6%], while the rest similar to NICE guidelines. The median (IQR) WTP threshold was differentiated between oncology [€51,000 (€50,000 – 57,000)] and non-oncology studies [€34,000 (€30,000 – €35,000); p-value<0.001]. In both type of studies, the median WTP thresholds were not statistically significantly different between GDP, NICE and NS methodologies.
Conclusions: Aligned with other countries where there is no standard WTP threshold to promote efficient use of healthcare resources, the most prominent practice in Greece was found to be that of one-to-three times the GDP per capita irrespective of type of treatment or outcome studied.