Measuring Health-Related Quality of Life

Abstract

Clinicians and policymakers are recognizing the importance of measuring health-related quality of life (HRQL) to inform patient management and policy decisions. Self- or interviewer-administered questionnaires can be used to measure cross-sectional differences in quality of life between patients at a point in time (discriminative instruments) or longitudinal changes in HRQL within patients during a period of time (evaluative instruments). Both discriminative and evaluative instruments must be valid (really measuring what they are supposed to measure) and have a high ratio of signal to noise (reliability and responsiveness, respectively). Reliable discriminative instruments are able to reproducibly differentiate between persons. Responsive evaluative measures are able to detect important changes in HRQL during a period of time, even if those changes are small. Health-related quality of life measures should also be interpretable--that is, clinicians and policymakers must be able to identify differences in scores that correspond to trivial, small, moderate, and large differences. Two basic approaches to quality-of-life measurement are available: generic instruments that provide a summary of HRQL; and specific instruments that focus on problems associated with single disease states, patient groups, or areas of function. Generic instruments include health profiles and instruments that generate health utilities. The approaches are not mutually exclusive. Each approach has its strengths and weaknesses and may be suitable for different circumstances. Investigations in HRQL have led to instruments suitable for detecting minimally important effects in clinical trials, for measuring the health of populations, and for providing information for policy decisions.

The clinical validity of the treatment satisfaction survey for intraocular pressure in ocular hypertensive and glaucoma patients

“…Accordingly, several validated surveys have been developed over the past several years that evaluate the impact of glaucoma on a patient's activities of daily living and vision. [1][2][3][4][5][6][7][8][9] Further, several years ago Laibovitz et al 10 validated the Comparison of Ophthalmic Medications for Quality of Life questionnaire (COMQoL), which was designed to compare specifically the tolerability of ophthalmic medications and to evaluate the effect of ocular hypotensive therapy on side effects, routine living activities, quality of life, compliance, and patient satisfaction with medication. The data were used to show an increased preference for dorzolamide compared to pilocarpine due to reasons of side effects and patient satisfaction.…”

Perceived symptoms and health-related quality of life reported by uncomplicated hypertensive patients compared to normal controls

“…Health-related quality of life (HQL) refers to the physical, emotional, and social impact of disease and treatments 8,9 and is distinct from physiologic measures of disease. [8][9][10][11] HQL measures may reflect disease or treatment characteristics that are not captured by clinical symptom measures and also may be an efficient way to represent the disease and treatment impact from the patient's perceptive.…”

Antihypertensive treatment using an angiotensin receptor blocker and a thiazide diuretic improves patients’ quality of life: The Saga Challenge Antihypertensive Study (S-CATS)

“…QOL refers to the physical, emotional and social impact of a disease and its treatments 20,21 and is distinct from the physiological measures of disease. [20][21][22][23] Estimation of QOL may assess the impact of a disease and its treatment from a patient's perspective to a greater extent than it assesses conventional clinical symptoms. To estimate the patients' QOL, several scoring systems in the form of questionnaires on various health-related factors have been developed and validated.…”