Abstract
Background and Purpose: The Short Physical Performance Battery (SPPB) is widely used for older adults since it has a high level of validity, reliability, and responsiveness in measuring function in this population. However, only a few studies of diagnostic accuracy have assessed SPPB capacity in detecting frailty and prefrailty by estimating more detailed measurement properties. Thus, the present study aimed to evaluate the SPPB's diagnostic accuracy in detecting frailty and prefrailty, in addition to identifying cut-off points for walking time and chair stand time.
Methods: This is a cross-sectional study composed of 786 community-dwelling older adults 60 years or older, in which sociodemographic and anthropometric data, frailty phenotype, and total SPPB score, as well as walking time and chair stand time, were assessed. Analysis of a receiver operating characteristic curve was performed to identify the cut-off point, sensitivity, and specificity in the total SPPB score, as well as the walking time and chair stand time for frailty and prefrailty screening. Accuracy and positive and negative predictive values were subsequently calculated.
Results and Discussion: The cut-off points identified for the total SPPB score, walking time, and chair stand time were 9 points or less (accuracy of 72.6%), 5 seconds or less, and 13 seconds or less, respectively, for frailty screening and 11 points or less (accuracy of 58.7%), 4 seconds or less, and 10 seconds or less, respectively, for prefrailty screening. The walking time showed greater frailty discriminatory capacity compared with the chair stand time (effect size = 1.24 vs 0.64; sensitivity = 69% vs 59%; and specificity = 84% vs 75%).
Conclusions: The total SPPB score has good diagnostic accuracy to discriminate between nonfrail and frail older adults using a cut-off point of 9 or less, being better to identify the true negatives (older adults who are not frail). Although the SPPB's diagnostic accuracy measures for detecting prefrailty were low to moderate, this instrument can help in screening prefrail older adults from the cutoff point of 11 or less in the total SPPB score. Identification of prefrail older adults enables implementing early treatment in this target audience and can prevent their advance to frailty.