Development and testing of a four-item version of the physical resilience instrument for older adults (PRIFOR-4)

The 16-item Physical Resilience Instrument for Older Adults (PRIFOR) has good clinimetric properties; however, a shortened PRIFOR would greatly enhance physical resilience measurements in clinical settings. The current analysis aimed to reduce the number of PRIFOR while maintaining its clinimetric properties, emphasizing on its factor structure and convergent validity. A longitudinal study was conducted among 863 patients aged 65 years or older. Four PRIFOR items with high factor loadings were selected to generate the short version of PRIFOR (PRIFOR-4). The PRIFOR-4 was found to have a unidimensional structure (comparative fit index = 0.999; Tucker-Lewis index = 0.998 in the confirmatory factor analysis results) with good convergent validity with various external measures (absolute r = 0.109-0.597; p-values<0.01). Because the PRIFOR-4 contains only four items, the completion time for the respondents reduced three fourths from the original PRIFOR, which may have a marked reduction in the response burden. The PRIFOR-4 is thus an easy-to-use measurement that saves time for healthcare professionals in clinical practice.