ABSTRACT
The primary objective of this study is to compare the construct, convergent and divergent validity and the reliability of three optimism scales. The study relied on a nonprobability sample of 100 social work students at Western Michigan University in the United States (Seventy-nine percent of the sample were female, and 21% were male). The sample’s mean age was 26.35 years, SD = 7.70. Sixty-nine percent (69%) of the respondents self-identified as White, and 31% self-identified as African American, Hispanic/Latino, multiethnic, Native American or Asian American. The study used confirmatory factor and multiple regression analyses (CFA and MRA). The findings show that the Life Orientation Test-Revised (LOT-R) and the Personal Optimism Scale (POS) were supported by three indicators of goodness of fit, while the Brief Interactive Optimism Scale-Garcia (BIOS-G) was supported by eight. The LOT-R showed no acceptable internal consistency indicators, but the POS and the BIOS-G showed several good internal consistency indicators. Correlations of all of these scales with the Physical Well-being Scale-Garcia (PWS-G) ranged from r (100) = .303, p = .002 to r (100) = .439, p = .000. The three scales had divergent validity because their scores did not differ by gender (LOT-R: t(100) = −.885, p = .383; POS: t(100) = −.263, p = .794; BIOS-G: t(100) = −.840, p = .407). The findings suggest the advisability of recommending the BIOS-G, which is short and easy to use and understand
