P.P.TAY1, P.L.K. YAP1, C.Y. CHEONG1, C. MALHOTRA2
Khoo Teck Puat Hospital1, Duke-NUS Graduate Medical School2
There has yet been a well-validated scale to assess the quality of life (QoL) in advanced dementia in Singapore. We sought to establish the psychometric properties of QUALID for assessing the QoL in patients with advanced dementia who live at home.
Data from 215 subjects [mean age±SD 83.6±8.2 years] in the “Panel study Investigating Status of Cognitively impaired Elderly in Singapore” were included. Principal component analysis (PCA) with varimax rotation was applied to assess the factor structure. Construct validity was performed by correlating QUALID with Bedford Alzheimer Nursing-Severity Scale (BAN-S) and Cohen-Mansfield Agitation Inventory (CMAI).
The median of QUALID score was 22 (interquartile range 17-27). QUALID showed acceptable internal consistency overall (Crohnbach’s α=0.77). PCA identified two factors accounting for 53.2% of the variance. The first factor was ‘Emotion’ (items were: facial expression of discomfort, appears physically uncomfortable, verbalization implying discomfort, being irritable and aggressive, appears calm, appears sad, cries, facial expression of discomfort). The second factor was ‘Well-Being’ (items were: smiles, enjoys eating, enjoys touching/being touched, enjoys social interaction). QUALID moderately and modestly correlated with CMAI (ρ= 0.463, P <0.01) and BAN-S (ρ= 0.305, P <0.01).
The QUALID has adequate reliability as well as construct and factor validity for assessing patients with advanced dementia in Singapore. It sets the stage for QUALID as a useful outcome measure in clinical care and research in this group of patients.