Psychometric Properties of the Farsi Version of the Schwartz Outcome Scale

Although improving well-being and psychological health is an important goal in the treatment of inpatient and outpatient populations, there are few measures in this field to assess such an important concept. The Schwartz Outcome Scale-10 (SOS-10) is a brief, cost-effective and user-friendly tool that could be used for this purpose in a wide variety of populations and clinical situations.

In this study, the psychometric properties of the SOS-10 were investigated among the Iranian population.

The participants consisted of 181 non-patients selected from among students of Iran University of Medical Sciences and Tehran University and 97 psychiatric patients recruited from Iran Psychiatric Hospital, Clinic of Tehran Psychiatric Institute, and one private clinic. The instruments used included Schwartz Outcome Scale-10, Inventory of Interpersonal Problems (IIP-32), Ryff’s Psychological Well-Being Questionnaire (PWB-18), Syndrome Checklist (SCL-25), Health Survey- Short Form (SF-12), Satisfaction with Life Scale (SWLS), and Beck’s Hopelessness Scale (BHS).

The findings revealed high internal consistency (Cronbach’s α: 0.913) and high test-retest reliability with intraclass correlation coefficients ranging between 0.910 - 0.971. The SOS-10 showed strong and positive correlations with SWL (r: 0.624, P < 0.001), SF-12 (r: 0.762, P < 0.001), and RWQ-18 (r: 0.656, P < 0.001) and strong negative associations with IIP-32 (r: -0.569, P < 0.001), BHS (r: -0.701, P < 0.001), and SCL-25 (r: -0.653, P < 0.001). According to principal component analysis, results indicated that the scale was unifactorial, and this uni-factor structure explained 56.37% of the variance of the scale and was well-fitted to the original version.

Generally, findings indicated that the Farsi version of SOS-10 has good reliability and validity and may therefore be used as a measure for assessing psychological health and well-being by researchers and clinicians in various settings.