The REST-IT study found the addition of zolpidem-controlled release (CR) provided a significant reduction in observer-rated measurement of suicidal ideation (the Columbia Suicide Severity Rating Scale) in 103 depressed outpatients with insomnia and suicidal ideation, but without significant change in a self-report measure of suicidal ideation (the Scale for Suicide Ideation). This secondary analysis of the REST-IT data examined the suicide item of another observer-rated scale, the Hamilton Rating Scale for Depression (HRSD), further clarifying the impact of insomnia-focused treatment on suicidal ideation. This analysis established a significant advantage for zolpidem-CR compared with placebo on the HRSD suicide item.