Suicidal behaviors and suicide risk

The effectiveness of the R4 intervention was evaluated using self-report responses to a battery of suicide-related measures at the intervals mentioned earlier. Suicidal behaviors consisted of ideations, plans, and attempts. Non-suicidal self-injury (NSSI) was also assessed but not included in suicidal-behavior totals. The occurrence of each behavior was assessed via Yes/No answers during the pre-T1, T1-T2, T1-T3 time points, and lifetime. The change in soldier outcomes over time (1) compared the change from baseline to follow-up among soldiers in the intervention group (within) and (2) contrasted the change over time for soldiers in intervention and control groups (between). These analyses were conducted using linked data, at the division-level, and also by R4-use status (as mentioned later).

The 12-month prevalence of suicidal behavior(s) at T1 and T3 and 6-month prevalence at T2 were computed for each time point. The 6-month incidence of suicidal behavior(s) at T2 was computed among soldiers with no reported lifetime suicidal behavior(s) at T1. Among soldiers with no reported prior suicidal behavior at T1, any report of suicidal behavior(s) since R4 implementation (T2 and/or T3) was tallied to determine any occurrence of new suicidal behavior(s) during the 12-month study period.

Data on a modified version of the Suicide Behaviors Questionnaire—Revised (SBQ-R) were also collected to assess individuals at risk for suicidal behaviors. The SBQ-R consisted of four items to assess different dimensions for determining suicide risk: (1) lifetime suicidal ideation, plan, and attempts; (2) frequency of suicidal ideation in the previous year; (3) suicidal threats; and (4) the likelihood of future suicide attempts. A score of ≥7 met the criteria for individual risk.⁵