• Kwai Ching Kan Health Psychology Programme, School of Healthcare Sciences,Faculty of Health Sciences,Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia
  • Ponnusamy Subramaniam School of Healthcare Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia
  • Rosdinom Razali Department of Psychiatry, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, 56000 Kuala Lumpur, Malaysia
  • Shazli Ezzat Ghazali Health Psychology Programme, School of Healthcare Sciences,Faculty of Health Sciences,Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia



Quality of life, dementia, caregiver, factor analysis, Malay language


The Quality of Life-Alzheimer’s Disease (QOL-AD) questionnaire is a reliable, valid and popular outcome measure in dementia related studies. However, to date there is no published report on adopted version of QOL-AD in Malay language. Thus this preliminary study aimed to evaluate the reliability and validity of the QOL-AD in Malay language for patients with dementia and to examine the level of agreement between patient-caregiver as a proxy reports on patient’s quality of life. A total of 65 patients with mild to moderate dementia and their caregivers were recruited from the psycho-geriatric clinic, Universiti Kebangsaan Malaysia Medical Centre using a cross sectional study design. The QOL-AD was translated into Malay language using the standard guidelines for cross-cultural adaptation of measure. The patient-caregiver dyads completed the QOL-AD in Malay language separately. Test-retest and internal consistency was evaluated for reliability and construct validity was tested with principal component factor analysis. The reliability of QOL-AD in Malay language was good with Cronbach alpha coefficients of 0.82 and 0.79 and intraclass correlation coefficients of 0.77 and 0.89 for patients and caregivers report respectively. Meanwhile a positive moderate agreement was achieved between patient and caregiver rating (r=0.60, p<0.01). The principal component factor analysis extracted 4 factors for both patient and caregiver reports which explained 66.02% (patients’ report) and 64.24% (caregivers’ report) of the total variance of the scale. As a conclusion, the QOL-AD in Malay language is a reliable and valid tool to measure the quality of life of people with mild to moderate dementia.


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How to Cite

Kwai Ching Kan, Ponnusamy Subramaniam, Rosdinom Razali, & Shazli Ezzat Ghazali. (2019). RELIABILITY AND VALIDITY OF THE QUALITY OF LIFE-ALZHEIMER’S DISEASE QUESTIONNAIRE IN MALAY LANGUAGE FOR MALAYSIAN OLDER ADULT WITH DEMENTIA. Malaysian Journal of Public Health Medicine, 19(1), 56–63.