Culturally-Adapted Translation, Psychometric and Predictive Validation of the Reported Edmonton Frail Scale-Thai version (REFS-Thai)

Abstract

Abstract Background: Frailty, a geriatric syndrome, results in increasing vulnerability, disability, and adverse health outcomes in older adults. In order to provide better care, early detection is the best approach to manage frailty. However, gaps exist in identifying frailty as instruments to measure the construct are not widely available. This is particularly true in the Thai language, where there are no published studies that investigate frail orthopedic patients in Thailand. To promote healthy aging and enhance equity of care, early identification of frailty with a reliable and cross-culturally sensitive instrument is necessary for reaching the goal in this population. This dissertation is composed of a series of research studies that focus on cross-cultural frailty in order to enhance equity and quality of care in an older Thai population. Objectives: The first paper aims to identify and evaluate frailty instruments used with hospitalized older orthopedic patients. The second paper aims to: 1) translate and culturally-adapt the Reported Edmonton Frail Scale (REFS) for use in hospitalized older adults in Thailand, and 2) evaluate the psychometric properties of the translated instrument, the REFS-Thai. The third paper aims to test the ability of the REFS-Thai to predict hospital outcomes compared with standard preoperative assessment measures, the American Society of Anesthesiologists physical status classification (ASA) and the Elixhauser Comorbidity Measure (EMC) in older Thai adults who were scheduled for a major orthopedic surgery. Research design: The data for the manuscripts of the dissertation were drawn from two main methodological approaches: a scoping review (the first study) and two observational studies—a cross-sectional (the second study) and a prospective cohort study (the third study). Subjects: Hospitalized older adults who were scheduled for elective surgeries (N = 341) Measures: In the observational studies, we used the REFS-Thai version, Mini-Cog Thai version, and the 4 “A” test- Thai version (4AT). The preoperative health status was assessed by the American Society of Anesthesiologists physical status classification (ASA), and the Elixhauser Comorbidity Measure (EMC) were extracted from medical records. For psychometric validity, the Cronbach’s alpha and inter-rater reliability were analyzed. Firth logistic regression and Robust Poisson regression were applied to evaluate the association between frailty and outcomes. Predictive ability was examined using cross-validation comparing the area under the receiver operating characteristic curve (AUC) and the mean squared errors (MSE). Results: The scoping review identified 14 reliable frailty instruments currently used in orthopedic patients. Of all of these instruments, the REFS appeared to be the most practical as it measured multiple dimensions of frailty, had few requirements for training, and could be administered in hospitals with limited-resources. For the cross-sectional study, the findings revealed that the REFS-Thai was a reliable tool to assess clinical frailty and had a content validity index of 0.97 and Cronbach’s alpha of 0.73. Inter-rater reliability was good, the linear weighted Kappa was 0.87 (p < 0.001). The instrument was completed, on average, in less than 6 minutes. For the prospective cohort study, frailty as evaluated by the REFS-Thai, showed significant association with an increased risk of postoperative complications (odds ratio [OR] = 2.38, p = 0.049), postoperative delirium (POD) (OR = 3.52, p = 0.034), and prolonged-length of stay (relative risk [RR] = 1.42, p = 0.043). Using the REFS-Thai shows good performance in predicting postoperative complication (AUC = 0.81, 95% confidence interval [CI] = 0.74-0.88) and POD (AUC = 0.81, 95% CI = 0.72-0.90). Conclusions: Comprehensive screening of frailty that is culturally appropriate has the potential to improve person-centered preoperative care. The REFS-Thai—a brief and valid instrument—may be a practical tool for the multidimensional evaluation of frailty in Thailand. Providing a frailty instrument that can be used in multiple settings results in enhancing equity for the screen of frailty.