Population-Based Testing for Undiagnosed Hepatitis C: A Systematic Review of Economic Evaluations

Recognising the significant public health threat posed by hepatitis C, international targets have been established by the World Health Organization with the aim of eradicating the hepatitis C virus (HCV) by 2030. With the availability of safe and effective therapies, the greatest challenge to achieving elimination is the identification and treatment of those currently undiagnosed. This systematic review aimed to identify and appraise the international literature on the cost-effectiveness of birth cohort, universal, and age-based general population testing for identifying people with undiagnosed chronic HCV infection.

A comprehensive literature search was undertaken in Medline, Embase and grey literature sources to identify studies published between 1 January 2000 and 17 July 2020. Retrieved citations were independently reviewed by two reviewers according to pre-defined eligibility criteria. Data extraction and critical appraisal were completed in duplicate. Study quality, relevance and credibility were assessed using the Consensus for Health Economic Criteria and the ISPOR questionnaires. All costs were reported in 2019 Irish Euro following adjustment for inflation and purchasing power parity. Willingness-to-pay (WTP) thresholds of €20,000 and €45,000 were adopted as reference points for interpreting cost-effectiveness in the narrative synthesis. The systematic review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria.

Overall, 4622 citations were retrieved in the literature search. Of these, 27 studies met the inclusion criteria. Six (22%) of the 27 studies were rated as low quality, 17 (63%) were moderate quality and four (15%) were high quality. Compared with no testing or risk-based testing: 14 of 16 (88%) cost-utility analyses found that birth cohort testing was cost effective, eight of nine (89%) analyses found that universal testing was cost effective, and eight of eight (100%) analyses found that age-based general population testing was cost effective. Cost effectiveness was influenced by disease prevalence and progression, testing and treatment uptake, treatment eligibility of those identified by testing, the cost of treatment and the proportion of those treated that achieve sustained virological response.

Overall, the international evidence supports the potential cost effectiveness of birth cohort, universal, and age-based general population testing, but is caveated by study generalisability, specifically the transferability of findings from one jurisdiction to another, and institutional variations in healthcare delivery systems and budgetary constraints. The cost effectiveness of each approach will vary according to population- and health system-specific characteristics such as epidemiological context, testing coverage, linkage to care and capacity to treat. Given issues regarding the transferability of economic evaluations (for example, model inputs and assumptions) and the significant resources required to implement these interventions, jurisdiction-specific economic evaluations and budget impact analyses will likely be required to inform investment and implementation decisions.

PROSPERO, CRD42019127159. Registered 29 April 2019.