Evaluation of the validity and reliability of the Alzheimer Disease-related Quality of Life Assessment Instrument

Judith D Kasper, Betty S Black, Andrew D Shore, Peter V Rabins, Judith D Kasper, Betty S Black, Andrew D Shore, Peter V Rabins

Abstract

The Alzheimer Disease-related Quality of Life (ADRQL) instrument was developed to assess health-related quality of life in people with AD using assessments from family caregivers or professional staff. Validity and reliability of the ADRQL in its original form and a revised version are assessed in a sample consisting of persons in 3 residential settings (community, assisted living, nursing home). The ADRQL exhibits good item-internal consistency (67.5% of items met 0.40 standard); high correlation of items to hypothesized scales (85% of items met criteria for 4 of 5 subscales and the overall instrument); a good range of scores (21.6 to 100 for total sample revised instrument); very low missing data; and internal-consistency reliability coefficients exceeding the minimum reliability standard for group comparisons (0.86 for total scores; range of 0.56 to 0.83 for subscales). In a community sample, the ADRQL discriminates between groups and is responsive over time in hypothesized directions. Characteristics of caregiver raters (community sample) including demographics and self-rated health were largely unrelated to scores. The results support the use of the ADRQL to evaluate health-related quality of life in persons with AD across various care settings and various stages of the disease. Modest correlations with cognitive and functional disability levels suggest that the ADRQL provides insight into other important dimensions of life experience in persons with dementia. The revised version has improved measurement properties and is recommended for use over the original.

Conflict of interest statement

Conflict of Interest Declaration

Drs. Kasper, Rabins and Black are entitled to a share of fees received on sales of the ADRQL questionnaire. The terms of this agreement are being managed by the Johns Hopkins University in accordance with its conflict of interest policies.

References

    1. Lawton MP. Quality of life in alzheimer disease. Alzheimer Dis Assoc Disord. 1994;8 Suppl 3:138–150.
    1. Rabins PV, Black BS. Measuring quality of life in dementia: Purposes, goals, challenges and progress. Int Psychogeriatr. 2007;19(3):401–407.
    1. Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med. 1993;118(8):622–629.
    1. Rabins PV, Kasper JD. Measuring quality of life in dementia: Conceptual and practical issues. Alzheimer Dis Assoc Disord. 1997;11 Suppl 6:100–104.
    1. Rabins PV, Kasper JD, Kleinman L, Black B, Patrick DL. Concepts and methods in the development of the ADRQL: An instrument for assessing health-related quality of life in persons with Alzheimer's disease. Journal of Mental Health and Aging. 1999;5(1):33–48. (This journal has ceased publication. The article can also be obtained directly from Drs. Rabins or Kasper.)
    1. Patrick DL, Erickson P. Concepts of health-related quality of life. In: Patrick DL, Erickson P, editors. Health Status and Health Policy. New York: Oxford University Press; pp. 76–112.
    1. Sloane PD, Zimmerman S, Williams CS, Reed PS, Gill KS, Preisser JS. Evaluating the quality of life of long-term care residents with dementia. Gerontologist. 2005;45 Spec No 1(1):37–49.
    1. Bergner M, Bobbit RA, Kressel S, Pollard WE, Gilson BS, Morris JR. The sickness impact profile: Conceptual formulation and methodology for the development of a health status measure. International Journal of Health Services. 1976;6:393–415.
    1. Black BS, Rabins PV, Kasper JD. Alzheimer Disease Related Quality of Life (ADRQL) User’s Manual. Baltimore Maryland:
    1. Black BS, Kasper J, Brandt J, et al. Identifying dementia in high-risk community samples: The memory and medical care study. Alzheimer Dis Assoc Disord. 2003;17(1):9–18.
    1. Rosenblatt A, Samus QM, Steele CD, et al. The Maryland assisted living study: Prevalence, recognition, and treatment of dementia and other psychiatric disorders in the assisted living population of central Maryland. J Am Geriatr Soc. 2004;52(10):1618–1625.
    1. Folstein MF, Folstein SE, McHugh PR. Mini-Mental State Examination. A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res. 1975;12(3):189–198.
    1. Tombaugh T, McIntyre N. The Mini-Mental State Examination: a comprehensive review. J Am Geriatr Soc. 1992;40:922–935.
    1. Chatfield M, Matthews FE, Brayne C and the Medical Research Council Cognitive Function and Ageing Study. Using the Mini-Mental State Examination for tracking cognition in the older population based on longitudinal data. J Am Geriatr Soc. 2007;55:1066–1071.
    1. Cronbach LF. Coefficient alpha and the internal structure of tests. Psychometrika. 1951;16:297–302.
    1. McHorney CA, Ware JE, Jr, Raczek AE. The MOS 36-item short-form health survey (SF-36): II. psychometric and clinical tests of validity in measuring physical and mental health constructs. Med Care. 1993;31(3):247–263.
    1. Ware JE, Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. conceptual framework and item selection. Med Care. 1992;30(6):473–483.
    1. McHorney CA, Ware JE, Jr, Lu JF, Sherbourne CD. The MOS 36-item short-form health survey (SF-36): III. tests of data quality, scaling assumptions, and reliability across diverse patient groups. Med Care. 1994;32(1):40–66.
    1. Heyman A, Peterson B, Fillenbaum G, Pieper C. Predictors of time to institutionalization of patients with Alzheimer's disease: The CERAD experience, part XVII. Neurology. 1997;48(5):1304–1309.
    1. Miller SC, Prohaska TR, Furner SE, Freels S, Brody JA, Levy PS. Time to nursing home admission for persons with Alzheimer's disease: The effect of health care system characteristics. J Gerontol B Psychol Sci Soc Sci. 1998;53(6):S341–S353.
    1. Yaffe K, Fox P, Newcomer R, et al. Patient and caregiver characteristics and nursing home placement in patients with dementia. JAMA. 2002;287(16):2090–2097.
    1. Neumann PJ, Araki SS, Gutterman EM. The use of proxy respondents in studies of older adults: Lessons, challenges, and opportunities. J Am Geriatr Soc. 2000;48(12):1646–1654.
    1. Logsdon RG, Teri L. Depression in alzheimer's disease patients: Caregivers as surrogate reporters. J Am Geriatr Soc. 1995;43(2):150–155.
    1. Hilari K, Owen S, Farrelly SJ. Proxy and self-report agreement on the stroke and aphasia quality of life scale-39. J Neurol Neurosurg Psychiatry. 2007;78(10):1072–1075.
    1. Logsdon RG, Gibbons LE, McCurry SM, Teri L. Assessing quality of life in older adults with cognitive impairment. Psychosom Med. 2002;64(3):510–519.
    1. Williams LS, Bakas T, Brizendine E, et al. How valid are family proxy assessments of stroke patients' health-related quality of life? Stroke. 2006;37(8):2081–2085.
    1. Duncan PW, Lai SM, Tyler D, Perera S, Reker DM, Studenski S. Evaluation of proxy responses to the stroke impact scale. Stroke. 2002;33(11):2593–2599.
    1. Lyketsos CG, Gonzales-Salvador T, Chin JJ, Baker A, Black B, Rabins P. A followup study of change in quality of life among persons with dementia residing in a long-term care facility. Int J Geriatr Psychiatry. 2003;18(4):275–281.

Source: PubMed

3
Abonner