A new instrument for measuring anticoagulation-related quality of life: development and preliminary validation.
Abstract
BACKGROUND: Anticoagulation can reduce quality of life, and different models of anticoagulation
management might have different impacts on satisfaction with this component of medical
care. Yet, to our knowledge, there are no scales measuring quality of life and satisfaction
with anticoagulation that can be generalized across different models of anticoagulation
management. We describe the development and preliminary validation of such an instrument
- the Duke Anticoagulation Satisfaction Scale (DASS). METHODS: The DASS is a 25-item
scale addressing the (a) negative impacts of anticoagulation (limitations, hassles
and burdens); and (b) positive impacts of anticoagulation (confidence, reassurance,
satisfaction). Each item has 7 possible responses. The DASS was administered to 262
patients currently receiving oral anticoagulation. Scales measuring generic quality
of life, satisfaction with medical care, and tendency to provide socially desirable
responses were also administered. Statistical analysis included assessment of item
variability, internal consistency (Cronbach's alpha), scale structure (factor analysis),
and correlations between the DASS and demographic variables, clinical characteristics,
and scores on the above scales. A follow-up study of 105 additional patients assessed
test-retest reliability. RESULTS: 220 subjects answered all items. Ceiling and floor
effects were modest, and 25 of the 27 proposed items grouped into 2 factors (positive
impacts, negative impacts, this latter factor being potentially subdivided into limitations
versus hassles and burdens). Each factor had a high degree of internal consistency
(Cronbach's alpha 0.78-0.91). The limitations and hassles factors consistently correlated
with the SF-36 scales measuring generic quality of life, while the positive psychological
impact scale correlated with age and time on anticoagulation. The intra-class correlation
coefficient for test-retest reliability was 0.80. CONCLUSIONS: The DASS has demonstrated
reasonable psychometric properties to date. Further validation is ongoing. To the
degree that dissatisfaction with anticoagulation leads to decreased adherence, poorer
INR control, and poor clinical outcomes, the DASS has the potential to help identify
reasons for dissatisfaction (and positive satisfaction), and thus help to develop
interventions to break this cycle. As an instrument designed to be applicable across
multiple models of anticoagulation management, the DASS could be crucial in the scientific
comparison between those models of care.
Type
Journal articleSubject
Administration, OralAged
Anticoagulants
Cost of Illness
Female
Focus Groups
Hematologic Tests
Humans
Long-Term Care
Male
Middle Aged
Outpatients
Patient Compliance
Patient Satisfaction
Psychometrics
Quality of Life
Sickness Impact Profile
Warfarin
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https://hdl.handle.net/10161/11676Published Version (Please cite this version)
10.1186/1477-7525-2-22Publication Info
Samsa, Greg; Matchar, David B; Dolor, Rowena J; Wiklund, Ingela; Hedner, Ewa; Wygant,
Gail; ... Edwards, Roger (2004). A new instrument for measuring anticoagulation-related quality of life: development
and preliminary validation. Health Qual Life Outcomes, 2. pp. 22. 10.1186/1477-7525-2-22. Retrieved from https://hdl.handle.net/10161/11676.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Rowena Joy Dolor
Professor of Medicine
Rowena J. Dolor, MD, MHS did her medical training and internal medicine residency
at Duke University Medical Center. She completed the Ambulatory Care/Health Services
Research fellowship at the Durham VA Medical Center in 1996 and obtained her Masters
in Health Sciences degree in Biometry (renamed MHS in Clinical Research) from the
Duke University School of Medicine in 1998. Dr. Dolor was a staff physician in the
Ambulatory Care Service at the Durham VA Medical Center and Research Associate at
t
David Bruce Matchar
Professor of Medicine
My research relates to clinical practice improvement - from the development of clinical
policies to their implementation in real world clinical settings. Most recently my
major content focus has been cerebrovascular disease. Other major clinical areas in
which I work include the range of disabling neurological conditions, cardiovascular
disease, and cancer prevention. Notable features of my work are: (1) reliance on
analytic strategies such as meta-analysis, simulation, decision analy
Gregory P. Samsa
Professor of Biostatistics & Bioinformatics
Greg Samsa is an applied statistician whose primary interests are in study design,
instrument development, information synthesis, practice improvement, effective communication
of statistical results, and teaching. He is a believer in the power of statistical
thinking, as broadly defined.
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