3049 — Comprehensive Assessment of Veterans' Preferences for Prostate Cancer Care: Validity of the Values Insight and Balance Evaluation Scales
Knight SJ (San Francisco VA Medical Center), Lim E
(Purdue University), Green GL
(San Francisco VA Medical Center), Latini DM
(Michael E. DeBakey VA Medical Center), Yale MS
(Purdue University), Chren MM
(San Francisco VA Medical Center), Sands LP
Understanding how to help Veterans make complex trade-offs among prostate cancer treatment outcomes is central to achieving the promise of shared decision-making in the Veterans Health Administration (VHA) where prostate cancer is a life-changing event for many. Our objective was to evaluate the reliability and construct validity of a clinically relevant and comprehensive measure of Veterans’ preferences for prostate cancer treatment.
The cross-sectional sample included men diagnosed with localized prostate cancer cared for in the VHA or affiliate (n = 394). Consented participants completed the Values Insight and Balance Evaluation scales (VIBEs), a 46-item measure of prostate cancer treatment preferences. The instrument is based on substantial input from Veterans, spouses, and clinicians, and an explicitly derived conceptual framework with eleven domains (personal and family responsibilities, survival, well-being, self-image, mood, urinary function, sexual function, gastrointestinal symptoms, hormonal symptoms, radiation therapy, and surgery). We determined internal consistency reliability using Cronbach’s alpha, and conducted confirmatory factor analysis using a robust maximum likelihood approach for non-normal distributions. Validation was assessed using the Satorra-Bentler Scales chi-square to evaluate model fit.
The majority of participants were Veterans in the VHA (68%), ranging in age from 40 to 89. Most were Caucasian (84%), married or living with a partner (61%), and had received active treatment (e.g., surgery, radiation) (78%). Internal consistency reliabilities ranged from 0.71 to 0.94. Confirmatory factor analysis revealed that eleven subscales fit the data well based on a non-significant chi-square statistic (p = 0.13), an RMSE < 0.05 (RMSE = 0.03), and a CFI > 0.95 (CFI = 0.99). Standardized estimates for subscale domains ranged from 0.48 to 0.88.
The VIBEs is reliable, and has strong evidence of construct validity. These results suggest that the VIBEs accurately and comprehensively measures treatment preferences in Veterans with prostate cancer.
Most patients with prostate cancer survive with the disease and treatment sequelae. Comprehensive measurement of patient treatment preferences is important because the choices are complex, affect multiple aspects of patients’ and families’ lives, and have long lasting consequences. Because it was developed with substantial input from Veterans, and has substantial evidence of reliability and validity, the VIBEs has strong potential to improve shared decision-making for Veterans with prostate cancer.