The purpose of this multisite study was to conduct a randomized controlled trial of an e-mail version of the caring letters (CL) suicide prevention intervention to determine whether the intervention is efficacious in preventing suicide behaviors among U.S. service members and veterans.
Psychiatric inpatients (N = 1,318) were recruited from four military medical centers and two VA hospitals and randomized to receive either 13 caring e-mails over two years or usual care.
There were 10 deaths from any cause in the CL group (three suicides) and 14 in the usual care group (seven suicides) during the individual two-year follow-up intervals. There was no statistically significant difference in the rate of all-cause hospital readmission between the study groups (RR = 1.13; 95% CI = 0.94, 1.36). There were no differences observed between groups on self-reported psychiatric hospital readmissions, self-reported suicide attempts, or other measures associated with risk for suicide.
No firm conclusions about the efficacy of the intervention can be made because the study was inadequately powered. There were no adverse events associated with the intervention, and implementation of the procedures was feasible in the military and veteran hospital settings. These results provide important methodological considerations for caring contact trials in military populations.