Gaps Between Self-Reported and Documented Use of a Health Care Service Portal Among Older Adults: Cross-Sectional Survey and Retrospective Electronic Data Study.

Background: Health care systems increasingly offer services to citizens through online portals, which have been found to be associated with patient satisfaction and better management of health concerns. Few studies have compared self-reported use with objectively documented portal use, especially among older adults. Objective: This study aimed to examine differences between documented and self-reported health portal use, and their associations with background variables and digital health literacy (DHL) among older adults. Methods: A cross-sectional telephone survey was conducted among 600 participants aged 60 years and older, who were sampled from a registry of members of a national health maintenance organization (HMO). The participants reported their use of the HMO's portal, their DHL, and demographic and background variables. Participants' use of the portal was retrospectively retrieved from the HMO's administrative database. Results: A large gap between self-reported use and documented use of the health portal was found: for example, while only 8.1% (46/566) reported not using the portal, the HMO's records indicated that 62% (372/600) did not make use of the portal. However, a positive correlation was found between self-reported use and documented use ( Conclusions: The findings indicate that users tend to overestimate their health portal use. Interpretations vary from measurement issues, such as social desirability bias regarding digital functioning or the perception that assisted use also constitutes usage, to signaling their identity as engaged digital health consumers. Future studies on digital health use should also include measures of electronically documented use and not only self-reported use.