Table 3.
Model results.
| ICBT-I Group (n) vs Comparison Group (n) | Relative Risk (95% CI) | ||||
|---|---|---|---|---|---|
| Insomnia Medicationsa | Insomnia, Depression, Anxiety Medicationsa | Primary Care Visitsb | Sleep Medicine or Psychiatry Visitsb | ||
| Model 1: Adjusted | ICBT-I (Sleepio) vs usual care (all) | 1.03 (0.91, 1.17) | 1.03 (0.95, 1.12) | 0.97 (0.89, 1.06) | 1.11 (0.90, 1.36) |
| Model 2: adjusted with session completion interaction | Sleepio 0 sessions vs Sleep Well, Live Well 0 sessions | 1.08 (0.85, 1.37) | 1.02 (0.89, 1.18) | 1.06 (0.93, 1.22) | 1.27 (0.94, 1.72) |
| Sleepio 1 session vs Sleep Well, Live Well 1 session | 1.07 (0.77, 1.47) | 1.02 (0.82, 1.25) | 0.91 (0.73, 1.12) | 1.01 (0.64, 1.58) | |
| Sleepio 2+ sessions vs Sleep Well, Live Well 2+ sessions | 0.95 (0.72-1.25) | 1.06 (0.88, 1.26) | 0.88 (0.74, 1.05) | 0.94 (0.57, 1.57) | |
| Sleepio 1+ sessions vs Sleep Well, Live Well 0 sessions | 0.92 (0.81, 1.05) | 1.04 (0.96, 0.13) | 1.05 (0.97, 1.13) | 1.30 (1.07, 1.57) | |
| Model 3: adjusted with insomnia interaction | Sleepio insomnia vs usual-care insomnia | 0.94 (0.84, 1.06) | 1.01 (0.93, 1.11) | 0.98 (0.90, 1.07) | 1.13 (0.90, 1.43) |
| Sleepio non-insomnia vs usual-care non-insomnia | 1.38 (0.99, 1.92) | 1.06 (0.96, 1.17) | 1.10 (1.00, 1.21) | 1.38 (1.11, 1.72) | |
Results of all models, matched analyses. Matched participants who accessed ICBT-I (Sleepio) to usual-care participants with a 1:6 ratio on race/ethnicity, sex, age, and study entry criteria. Model 1 is adjusted for 1-year baseline count and number of sessions completed. Model 2 is adjusted for 1-year baseline count, number of sessions completed, and the interaction between number of sessions and treatment. Model 3 is adjusted for 1-year baseline count, baseline insomnia status (diagnosis or medication for insomnia up to 1 year prior to case identification), and the interaction between baseline insomnia status and treatment. aDays’ supply of medications. Zero-inflated negative binomial model. Correlation among matched pairs is negligible and therefore not accounted for in the model. bPrimary care visits, sleep medicine/psychiatry visits. GEE model with negative binomial distribution, considering correlation between matched pairs. CI = confidence interval, GEE = generalized estimating equation, ICBT-I = internet cognitive behavioral therapy for insomnia.