Validity and reliability of the Checklist for Habitual Physical Activity for people 75 years and older in Japan.

Background: Despite health benefits, many older adults struggle to meet physical activity guidelines, leading to stagnant activity levels. While integrating physical activity into daily routines has been proposed as a promising strategy for older adults, fit-for-purpose measurement tools to assess such routines are lacking. The Checklist for Habitual Physical Activity (CHaPA) was developed based on the positive deviance approach and socio-ecological model to assess daily behaviours encouraging physical activity among adults aged 75 and older.