Abstract
Background: Available coronary artery disease (C AD)‐specific health‐related quality‐of‐life (HRQL) measures are not ideally suited for routine clinical practice. We report development of a valid and reliable CAD‐specific short‐form measure.
Hypothesis: The Integrated Therapeutics Group (ITG) CAD‐specific short‐form HRQL measure is reliable and valid for assessing the health status of patients with CAD.
Methods: In all, 409 patients (mean age 62.4 years) completed the 24–item CAD‐specific HRQL questionnaire. Factor analysis was used to identify the scaling of the 24 CAD‐specific items. Analysis of variance was used to reduce the number of items within each scale, and reliability (Cronbach's a), discriminant validity, and ceiling and floor effects of short‐form scales were evaluated. Short‐form scales were compared with the longer scales using relative validity coefficients. The CAD severity was assessed using New York Heart Association criteria, physician assessment, electrocardiogram results, the number of myocardial infarctions, and the number of CAD‐specific medications. Clinical validity of short‐form scales was then assessed based on their ability to discriminate across severity levels of these clinical criteria.
Results: Four scales were identified: Extent of Chest Pain, Functioning and Weil‐Being, Activities Level‐Physical, and Activities Level‐Social. The 24‐item questionnaire was reduced to a 13‐item short form, with reliability exceeding 0.70 for all four scales. Relative validity estimates comparing short‐form to original scales ranged from 0.68 to 2.58. Mean scores varied significantly (p < 0.05) by clinical severity, supporting the discriminant validity of the ITG CAD short‐form scales.
Conclusions: The ITG CAD short form (used alone or with a general HRQL measure) is valid and practical for assessing patients with CAD.
Keywords: coronary artery disease, quality of life, health status assessment
Full Text
The Full Text of this article is available as a PDF (779.4 KB).
References
- 1. American Heart Association : 1998 Heart and Stroke Statistical Update. Dallas. Tex.: American Heart Association, 1997. [Google Scholar]
- 2. Graboys TB: Coronary angiography—A long look at a short cue. J Am Med Assoc 1999: 282: 184–185 [DOI] [PubMed] [Google Scholar]
- 3. Huebb WA, Bellotti G, Oliveira S, Arie S, Albuquerque C, Jatene A, Pileggi F: The medicine, angioplasty or surgery study (Mass): A prospective, randomized trial of medical therapy, balloon angioplasty or bypass surgery for single proximal left anterior descending artery stenosis. J Am Coll Cardiol 1995: 26: 1600–1605 [DOI] [PubMed] [Google Scholar]
- 4. Graboys TB, Biegelsen B, Lampert S, Blatt CM, Lown B: Results of a second‐opinion trial among patients recommended for coronary angiography. J Am Med Assoc 1992: 268: 2537–2540 [PubMed] [Google Scholar]
- 5. U.S. Department of Health and Human Services : Quick Reference Guide for Clinicians, Cardiac Rehabilitation, as Secondary Prevention. October 17, 1995. [PubMed]
- 6. Cardiac Rehabilitation Guideline Panel : Cardiac rehabilitation as secondary prevention. Am Fain Pins 1995; 52 (8): 2257–2264 [PubMed] [Google Scholar]
- 7. Wu AW, Cagney KA: The role of quality of life assessments in medical practice In Quality of Life and Pharmacoeconomics in Clinical Trials, Second Edition, p. 517–522. New York: Lippincott‐Raven Publishers; 1996. [Google Scholar]
- 8. Steinberg EP, Tielsch JM, Schein OD, Javitt J, Sharkey P, Cassard S, Legro, M , Diener‐West M, Bass E, Damiano A, Steinwachs D, Sommer A: The VF‐14: An index of functional impairment in patients with cataract. Arch Ophthalmol 1994; 112: 630–638 [DOI] [PubMed] [Google Scholar]
- 9. Kaplan RM, Atkins CJ, Timms R: Validity of a quality of well‐being scale as an outcome measure in chronic obstructive pulmonary disease. J Chmn Dis 1984; 37 lpar;2): 85–95 [DOI] [PubMed] [Google Scholar]
- 10. Ware JE, Kemp JP, Buchner DA, Singer AE, Nolop KB, Goss TF: The responsiveness of disease‐specific and generic health measures to changes in the severity of asthma among adults. Qual Life Res 1998; 7 lpar;3): 235–244 [DOI] [PubMed] [Google Scholar]
- 11. McGrath MM, Bukstein DA, Buchner DA, Guzman GI, Landgraf JM, Goss TF: Assessment of the relationship between disease severity and general and disease‐specific health‐related quality of life in pediatric asthma patients. Ambul Child Health 1999: 5 lpar;3)249–261 [Google Scholar]
- 12. Wilson IB, Geary PD: Linking clinical variables with health‐related quality of life. A conceptual model of patient outcomes. J Am Med Assoc 1995; 273 lpar;1): 59–65 [PubMed] [Google Scholar]
- 13. Johnson KA, Partsch DJ, Tayor K, Rippe J, Musselman K: Pharmacist directed coronary artery disease clinic increased the percent of patients reaching National Cholesterol Education Program LDL‐cholesterol goal (abstr). Pharmacotherapy 1999: 19 lpar;4):475 [Google Scholar]
- 14. Partsch DJ, Johnson KA, Taylor K, Goodman LV, Hignett W, Graboys T, Musselman K: Impact of a pharmacist‐directed clinic on the medical management of patients with coronary artery disease (abstr). Pharmacotherapy 1999; 19 lpar;4):475 [Google Scholar]
- 15. Wenger NK, Naughton MJ, Furberg CD: Cardiovascular disorders In Quality of Life and Pharmacoeconomics in Clinical Trials. 2nd ed., p. 883–891 (Ed. Spilker B.). New York: Lippincott‐Raven Publishers, 1996. [Google Scholar]
- 16. Ware JE, Snow KK, Kosinski M, Gandek B: SF‐36 Health Survey‐Manual and Interpretation Guide. Boston: The Health Institute, New England Medical Center, 1993. [Google Scholar]
- 17. Bulpitt CJ, Fletcher AE: Measurement of quality of life in angina. J Hypertens 1987; 5(suppl I):s41–s45 [PubMed] [Google Scholar]
- 18. Rose G: Variability of angina. Some implications for epidemiology. Br J Prev Soc Med 1968: 22: 12–15 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19. Spertus JA, Winder JA, Dewhurst TA, Deyo RA, Prodzinski J, McDon Fihn SD: Development and evaluation of the Seattle Angina Questionnaire: A new functional status measure for coronary artery disease. J Am Coll Cardiol 1995: 25: 333–341 [DOI] [PubMed] [Google Scholar]
- 20. Hlatky MA, Boineau RE, Higginbotham MB, Lee KL, Mark DB, Califf RM, Cobb FR, Pryor DB: A brief self‐administered questionnaire to determine functional capacity (The Duke Activity Status Index). Am J Cardiol 1989; 64: 651–654 [DOI] [PubMed] [Google Scholar]
- 21. Wiklund I, Comrerford MB, Dimenas E: The relationship between exercise tolerance and quality of life in angina pectoris. J Clin Epidemiol 1991; 44: 981–988 [DOI] [PubMed] [Google Scholar]
- 22. Criteria Committee of the New York Heart Association : Nomenclature and criteria for diagnosis. In Diseases of the Heart and Blood Vessels, 6th ed., p. 110–114. Boston: Little Brown, 1964. [Google Scholar]
- 23. Visser MC, Fletcher AE, Parr G, Simpson A, Bulpitt CJ: A comparison of three quality of life instruments in subjects with angina pectoris: The Sickness Impact Profile, the Nottingham Health Profile, and the Quality of Well Being Scale. J Clin Epidemiol 1994; 47: 157–163 [DOI] [PubMed] [Google Scholar]
- 24. Dougherty CM, Dewhurst T, Nichol WP, Spertus J: Comparison of three quality of life instruments in stable angina pectoris: Seattle Angina Questionnaire, Short‐form Health Survey (SF‐36) and Quality of Life Index‐Cardiac Version III. J Clin Epidemiol 1998; 51 lpar;7): 569–575 [DOI] [PubMed] [Google Scholar]
- 25. Marquis P, Fayol C, Joire E, Leplege A: Psychometric properties of a specific quality of life questionnaire in angina pectoris patients. Qual Life Res 1995; 4: 540–546 [DOI] [PubMed] [Google Scholar]
- 26. Hays RD, Hayashi T, Carson S, Ware JE: A RAND note: User's Guide for the Multi‐trait Analysis Program (MAP), November 1988.
- 27. Deyo RA, Patrick DL: Barriers to the use of health status measures in clinical investigation, patient care, and policy research. Med Care 1989; 27:s254–s268 [DOI] [PubMed] [Google Scholar]
- 28. Wasson J, Keller A, Rubenstein L, Hays R, Nelson E, Johnson D, and The Dartmouth Primary Care COOP Project : Benefits and obstacles of health status assessment in ambulatory settings: The clinicians point of view. Med Care 1992; 30: ms42–ms49 [DOI] [PubMed] [Google Scholar]
- 29. Kaplan SH, Ware JE: The patient's role in health care and quality assessment In Providing Quality Care, the Challenge to Clinicians, I st ed, p. 25–69. (Eds. Goldfield N, Nash DB.). American College of Physicians; 1989. [Google Scholar]
- 30. Bukstein DA, McGrath MM, Buchner DA, Landgraf JM, Goss TF: Evaluation of a short‐form for assessing health‐related quality of life among pediatric asthma patients (abstr). American Academy of Allergy, Asthma and Immunology 55th Annual Meeting. February 26‐March 3, 1999, Orlando, Florida
- 31. Bungay KM, Ware JE: Measuring and Monitoring Health‐Related Quality of Life, p. 1–39. Kalamazoo, MI: Current Concepts A Scope Publication, 1993. [Google Scholar]
- 32. Bukstein DA: Practical approach to the use of outcomes in asthma: Traveling the road to better asthma care. Immunol Allergx Clin North Am 1996; 16 (4): 859–891 [Google Scholar]
- 33. McHorney CA, Tarlov AR: Individual patient monitoring in clinical practice: Are available health status surveys adequate? Qual Life Res 1995; 4: 293–307 [DOI] [PubMed] [Google Scholar]