Systematic review of the impact of health care expenditure on health outcome measures: implications for cost-effectiveness thresholds

ObjectiveEmpirical estimates of the impact of healthcare expenditure on health outcome measures may inform the cost-effectiveness threshold (CET) for guiding funding decisions. This study aims to systematically review studies that estimated this, summarize and compare the estimates by country income level.MethodsWe searched PubMed, Scopus, York Research database, and [anonymized] for Reviews and Dissemination database from inception to 1 August 2023. For inclusion, a study had to be an original article, estimating the impact of healthcare expenditure on health outcome measures at a country level, and presented estimates, in terms of cost per quality-adjusted life year (QALY) or disability-adjusted life year (DALY).ResultsWe included 18 studies with 385 estimates. The median (range) estimates were PPP$ 11,224 (PPP$ 223 - PPP$ 288,816) per QALY gained and PPP$ 5,963 (PPP$ 71 - PPP$ 165,629) per DALY averted. As ratios of Gross Domestic Product per capita (GDPPC), these estimates were 0.376 (0.041-182.840) and 0.318 (0.004-37.315) times of GDPPC, respectively.ConclusionsThe commonly used CET of GDPPC seems to be too high for all countries, but especially low-to-middle-income countries where the potential health losses from misallocation of the same money are greater.RegistrationThe review protocol was published and registered in PROSPERO (CRD42020147276).