Spanish adaptation and validation of the Pain Assessment Scale in Advanced Dementia (PAINAD) in patients with dementia and impaired verbal communication: cross-sectional study

OBJECTIVES: The aim of this study was to adapt and validate the Pain Assessment in Advanced Dementia (PAINAD) scale in Spanish. DESIGN: Cross-sectional observational study. SETTING: Two health districts of Andalusian provinces, located in the south of Spain, through the Andalusian network of Primary Healthcare centres and four institutions dedicated to the care of patients with dementia. PARTICIPANTS: A total of 100 older people, with a medical diagnosis of dementia and a score on the Global Deterioration Scale between 5 and 7 were assessed using the PAINAD scale. PRIMARY AND SECONDARY OUTCOME MEASURES: Psychometric properties including content validity, construct validity and reliability of the scale have been tested. RESULTS: The overall Item Content Validity Index was excellent (0.95). Regarding construct validity, it was confirmed that a lower use of analgesics implied a lower score on the PAINAD scale (p<0.05). The internal consistency of the scale was 0.76 and it increases to 0.81 if we remove the breathing item. Furthermore, the intraclass correlation coefficient (ICC) used to assess interobserver reliability was 0.94, whereas the ICC used to assess temporary stability was 0.55. CONCLUSIONS: The Spanish version of the PAINAD scale is a valid tool to assess pain in patients with dementia and inability to communicate verbally.