Southwestern Assessment of Processing Speed (SWAPS): A new brief test with demographically-corrected norms in an ethnically and educationally diverse population

Abstract

Objective. Neuropsychological measures of processing speed have long been used as sensitive indices of cognitive functioning. Most of these commonly used tests are proprietary, and there is a need for brief, freely available tools that can be used in diverse clinical and research settings. The Southwestern Assessment of Processing Speed (SWAPS) is a 60-second digit-symbol transcription task developed as a brief alternative to commercially available coding tests. Demographically-corrected normative data are presented along with reliability and sensitivity/specificity values in older adults with and without cognitive impairment. Method. SWAPS data from 915 healthy aging individuals (NC) and 858 subjects with clinical diagnoses of mild cognitive impairment (MCI; n = 430) and Alzheimer’s disease clinical syndrome (ADCS; n = 428) were obtained from the Texas Alzheimer’s Research and Care Consortium (TARCC). TARCC participants represent ethnically and educationally diverse community-dwelling individuals age 50+. Results. SWAPS scores showed the expected associations with age, sex, and education, and the interaction between age and education were significant predictors of SWAPS scores. Test-retest reliability in NC was good, and the SWAPS distinguished impaired and non-impaired groups with adequate to excellent sensitivity and specificity for the primary analyses, with optimal cut-off points provided. Raw score- to uncorrected normalized T-scores and demographically-corrected SWAPS T-scores using regression-based norms are presented along with scoring programs for the calculation of each. Conclusions. The SWAPS is a brief, free, easily administered test with demographically-corrected regression-based norms and promising utility for detection of cognitive impairment and efficient assessment of processing speed.