A secondary analysis of the role of geography in engagement and outcomes in a clinical trial of an efficacious Internet intervention for insomnia()

BACKGROUND: Online interventions for insomnia can increase access to treatments for those with limited access to services. What remains unknown is whether individuals from more isolated (vs. more densely populated) regions engage with, and benefit as much from, an online intervention. This secondary analysis examined the relationship of geographical indices with engagement and outcomes of an efficacious, fully automated online cognitive behavioral therapy for insomnia (CBT—I) program (Sleep Healthy Using the Internet-SHUTi). METHOD: 303 participants (M(age) = 43.3; SD = 11.6) were randomly assigned to SHUTi or an online patient education condition and assessed at baseline and post intervention. Rural code of participants was determined using participant zip codes. Distance to the nearest sleep medicine provider was calculated as the distance between the center of the nearest provider's city (from a publicly available list of CBT-I providers) and the center of the participants' zip code. Adherence outcomes were number of intervention core completions, sleep diaries, and logins. Sleep outcomes were insomnia severity as well as sleep onset latency and wake after sleep onset derived from online sleep diaries. RESULTS: Individuals were from a range of geographic locations. Most lived in fairly densely populated areas; however, there was a large variation in distance to the nearest sleep medicine provider. Findings indicate that the efficacy, adherence, and engagement with SHUTi were not impacted by where people lived. Controlling for age and gender did not impact any of the relationships among geography variables (i.e., distance, ruralness) and adherence or sleep related outcomes. CONCLUSIONS: Internet interventions must demonstrate that they can overcome obstacles posed by geography. This is the first study to examine the geographic location of participants and its association with engagement with, and outcomes of, online CBT-I.