Measuring cancer caregiver health literacy: validation of the health literacy of caregivers scale-cancer (HLCS-C) in an Australian population

Caregivers have been largely neglected in health literacy measurement. We assess the construct validity, and internal consistency of the Health Literacy of Caregivers Scale–Cancer (HLCS‐C), and present a revised, psychometrically robust scale. Using data from 297 cancer caregivers (12.4% response rate) recruited from Melbourne, Australia between January–July 2014, confirmatory factor analysis (CFA) was conducted to evaluate the HLCS‐C's proposed factor structure. Items were evaluated for: item difficulty, unidimensionality and overall item fit within their domain. Item‐threshold‐ordering was examined though one‐parameter Item Response Theory models. Internal consistency was assessed using Raykov's reliability coefficient. CFA results identified 42 poorly performing/redundant items which were subsequently removed. A 10‐factor model was fitted to 46 acceptable items with no correlated residuals or factor cross‐loadings accepted. Adequate fit was revealed (χ2 WLSMV = 1463.807[df = 944], p < .001, RMSEA = 0.043, CFI = 0.980, TLI = 0.978, WRMR = 1.00). Ten domains were identified: Proactivity and determination to seek information; Adequate information about cancer and cancer management; Supported by healthcare providers (HCP) to understand information; Social support; Cancer‐related communication with the care recipient (CR); Understanding CR needs and preferences; Self‐care; Understanding the healthcare system; Capacity to process health information; and Active engagement with HCP. Internal consistency was adequate across domains (0.78–0.92). The revised HLCS‐C demonstrated good structural, convergent, and discriminant validity, and high internal consistency. The scale may be useful for the development and evaluation of caregiver interventions.