Development of the Life-Worldly Communication Scale to Improve Quality of Life: Daily Conversation as Care for Older Adults.

The lack of daily conversation may lead to the deterioration of quality of life and cognitive function in older adults requiring long-term care. This study aimed to develop a scale to measure daily conversation among them, the Life-Worldly Communication Scale: LWCS, and to test its structural, convergent, and discriminant validity. The subjects were 539 older adults requiring long-term care in facilities and at home. A 24-item provisional scale was created, using a panel of experts. Structural validity of LWCS was examined from exploratory factor analysis to establish the factor structure, two confirmatory factor analyses for cross-validation, and measurement invariance between the institutional and home setting. Convergent validity was examined from the average variance extracted: AVE, composite reliability: CR, and simple regression analysis between LWCS and Interdependent Happiness Scale: IHS. Discriminant validity was examined using the heterotrait-monotrait ratio of correlations: HTMT. Multiple imputations were used to deal with missing data on these scales. The results showed that the goodness of fit of the three-factor, 11-item model obtained from the two-step CFA was SRMR = .043, RMSEA = .059, CFI = .978, and AGFI = .905. The model was confirmed for structural validity by measurement invariance tests: configural invariance (CFI=.973, RMSEA = .047), metric invariance (ΔCFI= .001, ΔRMSEA=-.004), scalar invariance (ΔCFI =-0.002, RMSEA = -0.003). Convergent validity was confirmed by AVE = .503~.772, CR = .801~.910, and simple regression analysis between LWCS and IHS (adjusted r=.18,  < .001). Discriminant validity was also confirmed among the three factors (HTMT=.496~.644). LWCS can contribute to the assessment of daily conversation in geriatric settings and research regarding its promotion.