PURPOSE Despite considerable interest in examining spirituality in health-related quality-of-life studies, there is a paucity of instruments that measure this construct. The objective of this study was to test a valid and reliable measure of spirituality that would be useful in patient populations.
METHODSWe conducted a multisite, cross-sectional survey using systematic sampling of adult outpatients at primary care clinic sites in the Kansas City metropolitan area (N = 523). We determined the instrument reliability (Cronbach's α, test-retest) and validity (confi rmatory factor analysis, convergent and discriminant validation) of the Spirituality Index of Well-Being (SIWB).
RESULTSThe SIWB contains 12 items: 6 from a self-effi cacy domain and 6 from a life scheme domain. Confi rmatory factor analysis found the following fi t indices: χ 2 (54, n = 508) = 508.35, P <.001; Comparative Fit Index = .98; TuckerLewis Index = .97; root mean square error of approximation = .13. The index had the following reliability results: for the self-effi cacy subscale, α = .86 and test-retest r = 0.77; for the life scheme subscale, α = .89 and test-retest r = 0.86; and for the total scale α = .91 and test-retest r = 0.79, showing very good reliability. The SIWB had signifi cant and expected correlations with other quality-of-life instruments that measure well-being or spirituality: Zung Depression Scale (r = 0 -.42, P <.001), General Well-Being Scale (r = 0.64, P <.001), and Spiritual Well-Being Scale (SWB) (r = 0.62, P <.001). There was a modest correlation between the religious well-being subscale of the SWB and the SIWB (r = 0.35, P <.001).
CONCLUSIONSThe Spirituality Index of Well-Being is a valid and reliable instrument that can be used in health-related quality-of-life studies.
INTRODUCTIONT here is continued interest in examining the association of religion and spirituality with health-related outcomes.1 Despite this interest, the use of small, nongeneralizable samples, confounding, and the lack of valid and reliable instruments that measure spirituality or religiosity compromise most studies in this fi eld.2 Although there is no shortage of instruments from the disciplines of sociology, psychology, and pastoral theology and chaplaincy, 3 these measures frequently are not applicable or useful in studies of individual or population health.The current study describes the development and evaluation of the Spirituality Index of Well-Being (SIWB), which was designed to measure the effect of spirituality on subjective well-being. Two assumptions guided our study design and analysis. First, we recognized that no global, yet parsimonious, instrument captures the complexity and depth of spirituality in any context, health care or otherwise. Next, based on our qualitative From a cultural and social perspective, spirituality and religion are especially salient in the lives of the elderly minority populations, 5,6 particularly within the settings of serious illness and end-of-life care.7 From a population health perspective, inc...