Abstract B23: Examining the psychometric properties of the Functional Assessment of Cancer Therapy-Breast (FACT-B) among Korean American breast cancer survivors

Abstract

Abstract Background: The 37-item Functional Assessment of Cancer Therapy-Breast (FACT-B) instrument has been validated and widely used in the literature to assess quality of life (QOL) among women with breast cancer. However, validation of the Korean version was conducted among breast cancer patients in Korea, and most studies in the United States have examined multiethnic samples with typically small numbers of Korean Americans (KA). This study examined the psychometric properties of FACT-B and its five subscales (physical well-being (PWB), social well-being (SWB), emotional well-being (EWB), functional well-being (FWB), and breast cancer subscale (BCS)) in a sample of KA breast cancer survivors. Methods: Data for this study are from a seven week randomized control trial aiming to increase QOL and reduce perceived stress among KA breast cancer survivors. Participants completed the FACT-B instrument at baseline, end of the program, and 7-weeks post intervention. In this study, baseline assessments of FACT-B were examined from 61 KA women in the Washington, D.C. metropolitan area with stages 0 to IV breast cancer. Participants' ages ranged from 30 to 83 (mean=56.7; SD=10.2). Principal component analysis (PCA) was conducted to examine FACT-B and its subscales. The factor correlation matrix was examined to determine the appropriate rotation method. Internal reliability was assessed using Cronbach's alpha. Results: Varimax rotation was employed given that factor correlations were mostly less than 0.32, which suggests that the variance between factors do not greatly overlap. The internal reliability of FACT-B in this sample was found to be good (α=.88). Moreover, the internal reliabilities were also good for PWB, SWB, and FWB (α=.85 to .89), but lower for EWB and BCS (α=.69 and α=.67 respectively). In general, these findings are consistent with the literature on White (α=.64-.91), African American (α=.77-.92), and Latina women (α=.72-.91) with breast cancer. Some variations were found between our study on KA women and other literature on breast cancer patients in China, Japan, and Korea. The internal reliability for EWB was lower in KA women (α=.69) as compared to Chinese women (α=.84), Japanese women (α=.74), and women in Korea (α=.79). However, our reliability is the same as that found in the initial FACT-B validation study by Brady et al. (1997) (α=.69). For other subscales, the internal reliabilities were similar or lower than in our sample. The initial PCA with varimax rotation retained 11 factors with eigenvalues above 1. However, 4 factors had only one or two items with factor loadings of at least |0.4|. Thus, 5 factors were specified based on the established number of subscales in the literature. The only item with a factor loading less than .4 was a question that asked how bothered participants were by hair loss. The low loading may be a result of few participants experiencing hair loss at the time of the survey. Interestingly, an item asking participants about how much they worry about dying had a negative loading even after reverse coding (ℓ=-.48), meaning those who worry more tend to have better QOL. One reason may be that concerns regarding death motivate some individuals to reassess priorities and better allocate their time on things that are more valued and enjoyable. Conclusions: Our findings were consistent with those from previous studies examining White, African American, and Latina women with breast cancer. In addition, FACT-B and its subscales had similar or higher internal reliabilities in our sample of KA women with breast cancer as compared to breast cancer patients in China, Japan, and Korea, with the exception of EWB. Overall, FACT-B was found to be reliable in our sample of KA breast cancer survivors providing additional support for its use in this population. Citation Format: Mary Y. Jung, Min Q. Wang, Sunmin Lee. Examining the psychometric properties of the Functional Assessment of Cancer Therapy-Breast (FACT-B) among Korean American breast cancer survivors. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B23.