Table 3.
SI rates by treatment condition and insomnia remission status at posttreatment and 1-year follow-up
| CBTI | Control | Remission | Non-remission | |||
|---|---|---|---|---|---|---|
| Alleviating SI: Rates of SI at posttreatment and 1-year follow-up for patients who endorsed SI before treatment | ||||||
| Posttreatment | ||||||
| SI endorsed | 18/60; 30.0% | 36/66; 54.5% | χ2 = 7.73, p = .005, RR = 1.82 | 8/40; 20.0% | 46/86; 53.5% | χ2 = 12.50, p < .001, RR = 2.68 |
| 1-year follow-up | ||||||
| SI endorsed | 16/56; 29.6% | 29/62; 46.8% | χ2 = 4.13, p = .042, RR = 1.58 | 8/37; 21.6% | 37/81; 53.5% | χ2= 6.23, p = .013, RR = 2.12 |
| SI endorsed (ITT) | 17/60; 28.3% | 30/66; 45.5% | χ2 = 3.94, p = .047, RR = 1.61 | 8/43; 18.6% | 39/83; 47.0% | χ2 = 9.76, p = .002, RR = 2.53 |
| Preventing SI: Rates of SI at posttreatment and 1-year follow-up for patients who denied SI before treatment | ||||||
|---|---|---|---|---|---|---|
| Posttreatment | ||||||
| SI endorsed | 15/298; 5.0% | 10/234; 4.3% | χ2 = 0.17, p = .681 | 3/195; 1.5% | 22/337; 6.5% | χ2 = 6.87, p = .009, RR = 4.33 |
| 1-year follow-up | ||||||
| SI endorsed | 12/270; 4.4% | 15/220; 6.8% | χ2 = 1.31, p = .252 | 8/191; 4.2% | 19/299; 6.4% | χ2 = 1.05, p = .305 |
| SI endorsed (ITT) | 14/298; 4.7% | 18/234; 7.7% | χ2 = 2.08, p = .149 | 8/209; 3.8% | 24/323; 7.4% | χ2 = 2.91, p = .088 , RR = 1.95 |
SI, suicidal ideation over the past week, operationalized as endorsing the SI item on the quick inventory of depressive symptomatology, 16-item self-report version; Remission, insomnia severity index score ≤ 7; Non-remission, insomnia severity index score ≥ 8. One-year follow-up data are derived from per-protocol analysis, except when noted as ITT (intent-to-treat; these ITT results are reported in the Supplement). χ2, chi-square for comparing SI rates between treatment conditions and between remission statuses; RR, relative risk; CBTI, cognitive-behavioral therapy for insomnia.