Journal of Abnormal Psychology 1997. Vol. 106, No. 2, 260-265 Copyright 1997 by the American Psychological Association, Inc 002I-843X/97/S3.00 The Modified Scale for Suicidal Ideation: Factors of Suicidality and Their Relation to Clinical and Diagnostic Variables Thomas E. Joiner, Jr. University of Texas Medical Branch at Galveston M. David Rudd and M. Hasan Rajab Scott and White Clinic and Hospital and Texas A&M University Health Sciences Center The authors conducted the 1st large-sample factor-analytic study of the Modified Scale for Suicidal Ideation (MSSI; I. W. Miller, W. H. Norman, S. B. Bishop, & M. G. Dow, 1986) on a sample of 330 suicidal young adults. Factor analyses revealed 2 MSSI factors: Suicidal Desire and Ideation (ongoing thoughts or desires about suicide) and Resolved Plans and Preparation (intense thoughts, plans, and courage and capability to commit suicide). The Resolved Plans and Preparation factor was more related to Attempt versus Ideator status than was the Suicidal Desire and Ideation factor. The Suicidal Desire and Ideation factor was more highly related to depressotypic indicators than was the other factor, suggesting that level of depression, although predictive of ideation, may not be as strong aeon-elate of preparation. Comparison of depression- and anxiety-related diagnostic groups on the MSSI factors revealed little difference, consistent with previous work highlighting the occur- rence of suicidality across diagnostic groups. These findings have implications for the structure of suicidality, as well as its clinical assessment. Beck, Kovacs, and Weissman (1979) developed the Scale for Suicidal Ideation, a semistructured, clinician-rated measure of suicidality. Although Beck et at. provided some initial reliability and validity data, an essential piece of the scale's construct validity regarding its factorial structure was not fully assessed. In an exploratory analysis, Beck et al. found three factors: Active Suicidal Desire, Passive Suicidal Desire, and Suicidal Behavior. Using a self-report version of the scale, Steer, Rissmiller, Ranieri, and Beck (1993) reported a slightly different structure, again using an exploratory approach. These authors identified the following factors: Desire for Death, Active Suicidal Desire, and Preparation for Suicide (cf. Beck, Kovacs, & Weissman's [1979] Suicidal Behavior). Although the Steer et al. and Beck, Kovacs, and Weissman studies assigned similar labels to the three factors, there was substantial variability regarding which items comprised which factor (e.g., wish to die loaded on Active Thomas E. Joiner, Jr., Department of Psychiatry and Behavioral Sci- ences, University of Texas Medical Branch at Galveston; M. David Rudd and M. Hasan Rajab, Department of Psychiatry and Behavioral Sciences, Scott and White Clinic and Hospital, and College of Medicine, Texas A&M University Health Sciences Center. Preparation of this article was supported in part by a "Young Investiga- tor Award from the National Alliance for Research on Schizophrenia and Depression, by a component of an Institutional Grant from the American Suicide Foundation (principal investigator, Charles E. Holzer III), and by Grant MH48097 from the National Institute of Mental Health. Correspondence concerning this article should be addressed to Thomas E. Joiner, Jr., Department of Psychiatry and Behavioral Sciences, 3.102 Graves Building, 301 University Boulevard, University of Texas Medical Branch, Galveston, Texas 77555-0425. Electronic mail may be sent via Internet to Thomas.Joiner @utmb.edu. Suicidal Desire in the Beck, Kovacs, & Weissman study, but in the Steer et al. study, wish to die loaded on the Wish for Death factor). Miller, Norman, Bishop, and Dow (1986) provided a revision of the original scale (Modified Scale for Suicidal Ideation; MSSI), along with convincing reliability and construct validity data (e.g., reliability estimates in the .90s, convergence with other measures of suicidality). However, as with the original version, factorial validity data were, to our knowledge, lacking. The only exception is a study by Clum and Yang (1995) on 91 college students who experienced suicidal ideation. Clum and Yang reported three MSSI factors: Suicidal Desire. Preparation for Attempt, and Perceived Capability of Making an Attempt. The present study was designed to assess the factorial struc- ture of the MSSI among a large clinical sample. Lack of such data represents an important gap in the literature on this useful tool. In so doing, we have not only provided essential psycho- metric validity data for a specific instrument, but have also obtained data on the general structure of suicidality and on the clinical and diagnostic correlates of suicidality factors (i.e., depression, hopelessness, life events, problem-solving style, di- agnostic status, ideator vs. attempter status). Method Participants Participants included 330 (271 male, 59 female) individuals, evalu- ated at intake prior to entry into a study on the efficacy of a time- limited, problem-solving treatment for suicidal young adults (Rudd et al., 1996). Participants were referred from two outpatient clinics, a 20- bed inpatient facility, and an emergency room, all affiliated with a major U.S. army medical center. Mean age for the total sample was 22 (SD = 2.3 years). The gender 260