A Psychometric Evaluation of Three Pain Rating Scales for People with Moderate to Severe Dementia

Little comparative information exists regarding the reliability and validity of pain rating scales for nurses to assess pain in people with moderate to severe dementia in residential aged care facilities. The objective of this study was to evaluate the relative psychometric merits of the Abbey Pain Scale, the DOLOPLUS-2 Scale, and the Checklist of Nonverbal Pain Indicators Scale, three well-known pain rating scales that have previously been used to assess pain in nonverbal people with dementia. An observational study design was used. Nurses (n = 26) independently rated a cross-section of people with moderate to severe dementia (n = 126) on two occasions. The Abbey Pain Scale and the DOLOPLUS-2 Scale showed good psychometric qualities in terms of reliability and validity, including resistance to the influence of rater characteristics. The Checklist of Nonverbal Pain Indicators Scale also had reasonable results but was not as psychometrically strong as the Abbey Pain Scale and DOLOPLUS-2 Scale. This study has provided comparative evidence for the reliability and validity of three pain rating scales in a single sample. These scales are strong, objective adjuncts in making comprehensive assessments of pain in people who are unable to self-report pain due to moderate to severe dementia, with each having their own strengths and weaknesses. The DOLOPLUS-2 Scale provides more reliable measurement, and the Abbey Pain Scale may be better suited than the other two scales for use by nurse raters who only occasionally use pain rating scales or who have lower level nursing qualifications.