Table 2.
Matched cohort characteristics.
| Characteristics | ICBT-I | Usual Care | Total | Standardized Difference* |
|---|---|---|---|---|
| n | 638 | 3,825 | 4,463 | 0.00101 |
| Age, mean (SD), y | 54.5 (15.13) | 54.5 (15.13) | 54.5 (15.13) | |
| Sex | 0.00051 | |||
| Female | 446 (69.9) | 2,673 (69.9) | 3,119 (69.9) | |
| Male | 192 (30.1) | 1,152 (30.1) | 1,344 (30.1) | |
| Race/ethnicity | 0.00492 | |||
| White | 453 (71) | 2,718 (71.1) | 3,171 (71.1) | |
| Black | 30 (4.7) | 180 (4.7) | 210 (4.7) | |
| Hispanic | 102 (16.0) | 612 (16.0) | 714 (16.0) | |
| Asian/Pacific Islander | 29 (4.5) | 174 (4.5) | 203 (4.5) | |
| Other | 8 (1.3) | 48 (1.3) | 56 (1.3) | |
| Missing | 16 (2.5) | 93 (2.4) | 109 (2.4) | |
| Marital status | 0.12799 | |||
| Married/partnered | 301 (47.2) | 2037 (53.3) | 2338 (52.4) | |
| Single/separated | 235 (36.8) | 1,252 (32.7) | 1,487 (33.3) | |
| Widowed | 30 (4.7) | 146 (3.8) | 176 (3.9) | |
| Other | 2 (0.3) | 5 (0.1) | 7 (0.2) | |
| Missing | 70 (11) | 385 (10.1) | 455 (10.2) | |
| Study entry criteria | ||||
| Had insomnia medication order in the past 14 days | 106 (16.6) | 725 (19) | 831 (18.6) | −0.06122 |
| Had insomnia diagnosis in the past 14 days | 216 (33.9) | 1,276 (33.4) | 1,492 (33.4) | 0.01051 |
| Had depression diagnosis in the past 14 days | 246 (38.6) | 1,412 (36.9) | 1,658 (37.1) | 0.03390 |
| Had anxiety diagnosis in the past 14 days | 320 (50.2) | 2,014 (52.7) | 2,334 (52.3) | −0.04997 |
| Had insomnia diagnosis/medication at baselinea | 353 (55.3) | 1,886 (49.3) | 2,239 (50.2) | 0.12079 |
| Number of sessions completed | ||||
| 0 | 197 (30.9) | 3,401 (88.9) | 3,598 (80.6) | 1.48211 |
| 1 | 233 (36.5) | 136 (3.6) | 369 (8.3) | |
| 2+ | 208 (32.6) | 288 (7.5) | 496 (11.1) | |
| Baseline count per month, mean (SD)b | ||||
| Insomnia medication days’ supply | 5.3 (10.83) | 5.1 (10.59) | 5.1 (10.62) | 0.02199 |
| Insomnia/depression/anxiety medication days’ supply | 29.0 (27.41) | 25.7 (26.86) | 26.1 (26.96) | 0.12354 |
| Primary care visits | 1.0 (0.95) | 0.9 (0.83) | 0.9 (0.85) | 0.12890 |
| Psychiatry/sleep medicine visits | 0.8 (1.42) | 0.5 (1.09) | 0.6 (1.14) | 0.17548 |
| Follow-up count per month, mean (SD)c | ||||
| Insomnia medication days’ supply | 5.1 (10.39) | 5.1 (10.92) | 5.1 (10.84) | 0.00256 |
| Insomnia/depression/anxiety medication days | 29.9 (28.56) | 25.9 (28.08) | 26.5 (28.18) | 0.13805 |
| Primary care visits | 1.0 (1.02) | 0.9 (0.92) | 0.9 (0.93) | 0.09927 |
| Sleep medicine or psychiatry visits | 0.8 (1.44) | 0.6 (1.26) | 0.6 (1.29) | 0.18278 |
Continuous data are presented as mean ± SD; categorical variables are presented as n (%). Characteristics of participants who accessed ICBT-I and matched participants in usual care: matched cohort. Matched participants who accessed ICBT-I (Sleepio) to usual-care participants with a 1:6 ratio based on race/ethnicity, sex, age, Sleep Well, Live Well class participation, and study entry criteria. *Standardized difference = difference in means or proportions divided by standard error; imbalance defined as absolute value > 0.20 (small effect size). aHad an insomnia diagnosis or any of the insomnia medication 12 months prior to outreach. b12 months prior to outreach. c12 months after outreach. ICBT-I = internet cognitive behavioral therapy for insomnia.