Testing trajectories for GetCheckedOnline in British Columbia: Implications for equity, stewardship and sustainability of digital STI testing services

BackgroundDigital services for sexually transmitted and blood borne infection (STBBI) testing may influence demand in publicly funded health systems by enabling low barrier, self-directed access to testing, raising concerns about repeated use and sustainability. We examined longitudinal utilization of GetCheckedOnline, British Columbias digital STBBI testing service, to characterize testing trajectories and assess factors associated with higher intensity use. MethodsWe conducted a retrospective cohort study using GetCheckedOnline program data for users who created an account between April 2020 and November 2022, with 24 months of follow-up. We used group-based trajectory modelling to identify patterns of testing over time among (1) all users and (2) users with at least one test. Multilevel regression models with local health area random intercepts were used to examine associations between higher intensity trajectory membership, individual risk indicators, and geographic clustering. ResultsAmong 34,228 users, 22,542 (65.9%) completed at least one test and 42,451 tests were conducted (median 1; range 0-44). Two trajectories were identified in both analytic samples, with a minority demonstrating sustained higher intensity testing. The top 10% of users accounted for 39.6% of tests. Higher intensity trajectory membership was associated with sexual risk indicators including having multiple partners, condomless sex with multiple partners, and prior STBBI diagnosis. Geographic clustering across local health areas was modest in the null model (ICC 0.042) and attenuated with adjustment. ConclusionGetCheckedOnline utilization reflects a prevention-oriented pattern that appears more consistent with service needs than indiscriminate overuse. A small subset of users with elevated sexual risk account for higher-intensity testing. Findings support risk aligned stewardship including education and differentiated guidance, rather than universal restrictions to reducing testing volumes. Author SummaryDigital services are being used to make testing for sexually transmitted and blood borne infections (STBBIs) easier to access. Some health systems decision makers worry that online testing could lead to too much testing and higher costs. We examined how people used GetCheckedOnline, British Columbias public online STBBI testing service, over two years. Most people used the service only once or tested occasionally (less than once in six months). A smaller group tested more often. People who tested more often were also more likely to report higher sexual health risk, such as having multiple partners or a recent STBBI diagnosis. This suggests that repeat testing is often done by people who may benefit from testing more often, rather than people testing without need. For health systems, this means it may be more helpful to give clear guidance and education about when to test instead of placing broad limits on access to online testing.