A test of invariance of the construct of suicidal ideation across three diverse samples

Suicide treatment research has placed major emphasis on preventing behavior, an observable phenomenon. Suicidal ideation (SI), however, is a distressing experience that annually impacts >15 million Americans; yet the construct validity of SI has not been well established, limiting empirical attention.

We compared the coherence of three SI items (diminished wish to live, urge to die/controllability, suicide intent/expectations) and four related items across three adult samples (N = 314) that differed based on current SI severity and assessment time-scales (retrospective versus momentary).

A measurement model with scalar invariance had acceptable fit (CFI = 0.969, RMSEA = 0.076), indicating that the SI items consistently loaded onto one construct across samples. The structural model with metric invariance also had acceptable fit (CFI = 0.956, RMSEA = 0.063) and three of four related items (burdensome, hopelessness, and fatigue, but not agitation) were associated with SI across samples.

Use of existing data limited the items considered.

Suicidal ideation is a coherent construct independent of the items used to assess it, the assessment's time-scale (retrospective versus momentary), or the severity of thoughts, and is worthy of greater empirical, clinical, and policy attention.