The health and economic benefits of immunization may extend beyond the elements traditionally included in cost-effectiveness analyses (CEAs). This review investigated how broader impacts are considered in economic evaluations of vaccines and whether their inclusion would substantially change CEA findings.
We reviewed CEAs of vaccines associated with the largest global health burden, published from 2014 to 2019 using the Tufts CEA Registry and Tufts Global Health CEA Registry. We supplemented this with a systematic review of published and grey literature. We conducted descriptive analyses to examine the frequency of inclusion of specific social factors and study characteristics associated with their inclusion. We also conducted a case study of the human papilloma virus (HPV) vaccine to illustrate the potential change in CEA findings from selected social impacts.
We identified 475 relevant health economic assessments. Overall, 40% of studies included at least one category of social impact. The most commonly included non-healthcare cost among cost-per-QALY studies was productivity (25%), while cost-per-DALY studies reported transportation costs most frequently (24%). Few studies examined the impact of vaccination on other sectors such as education and housing (<3%). Middle-income and North American settings were positively associated with social impact inclusion, while sub-Saharan African location was negatively associated. In the HPV case study, the addition of nonhealth costs improved cost-effectiveness by up to 90% or made the vaccine cost-saving, depending on geographic setting. The cost-saving scenario saved up to $30,000 in costs per case of cervical cancer averted.
A minority of vaccine CEAs include social impacts, particularly for nonhealth sectors. The omission of these impacts may result in a systematic undervaluation of vaccines from a societal perspective. Further efforts are required to document the full benefits of vaccination for policymaker consideration.