The development of a valid and reliable scale for rating anxiety in dementia (RAID)

A rating scale to measure anxiety in dementia sufferers was developed and e valuated in a sample of 51 inpatients and 32 day-hospital patients. Anxiety scores were not related to sex, age, accommodation or DSM-IV diagnosis of the type of dementia. However, both subjects with physical illnesses and su bjects with insight into their memory problems had significantly higher anx iety scores. The kappa values for inter-rater reliability ranged from 0.51 to I and for test-retest reliability from 0.53 to 1, which indicates modera te to good reliability. The overall agreement on individual items ranged fr om 82-100% (inter-rater) and 84-100% (test-retest). The professionals worki ng in the care of the elderly and carer groups felt that the scale was comp rehensive and all the items in the scale were important, thereby confirming that it has good content validity. The scale significantly correlated with other anxiety scales and also with independent ratings both by a consultan t psychiatrist and also nursing staff, indicating good concurrent validity. Anxiety scores were significantly higher in dementia patients who fulfille d modified DSM-IV criteria for anxiety and clinical diagnosis of anxiety di sorder. This showed evidence of good criterion validity. Factor analysis sh owed five factors, including all items of the scale. Scores of 11 and above on the scale indicated significant clinical anxiety. Overall, the scale ha d good reliability and validity. It should be a useful clinical and researc h instrument for assessing anxiety in dementia sufferers.