High level of preferences for routines is an indicator of psychological vulnerability in older adults. However, the psychometric properties of the Preferences for Routines Scale (PRS) initially validated in a small selected sample of older adults revealed a low Cronbach's α (.50) in the general elderly population. The present study aims to improve the PRS using the data from the "AMI" and "PAQUID" population-based studies. Among 718 older persons, the most discriminative items are identified using item response theory methodology. A short form of the PRS (PRS-S) included five of the ten items of the original scale and showed improved internal consistency and test-retest reliability. The factors associated with the PRS-S are similar to those found in previous studies. Norms are provided according to gender and educational level. The reduction of the number of items tends to facilitate its administration and promote its use in both clinical and epidemiologic research contexts.
Keywords: daily life functioning; item response theory; older adults; psychometrics; routinization.