Measuring health-related quality of life by experiences: the experience sampling method.

OBJECTIVE: To explore the potential value of obtaining momentary, instead of retrospective, accounts of the description and valuation of a person's own health-related quality of life (HRQOL). METHODS: Momentary HRQOL was examined with the experience sampling method (ESM) in 139 participants from four different samples. The ESM consists of a so-called beep questionnaire that was administered 10 times a day by an electronic device. Feasibility was determined by assessing willingness to participate in the study and by analyzing the percentage of dropouts and the number of completed beep questionnaires. Multilevel analysis was used to investigate the relation between momentary HRQOL and momentary feelings and symptoms. The relation between momentary outcomes and the EuroQol visual analogue scale was investigated with a multiple regression model. RESULTS: The overall participation rate was low, but there were no dropouts and the number of completed beeps was comparable to that in other studies. Multilevel analysis showed that feelings and symptoms were significant predictors of momentary HRQOL. The strength of these relations differed among three patient groups and a population-based sample. The EuroQol visual analogue scale was not predicted by momentary feelings and symptoms. CONCLUSIONS: We can conclude that the use of the ESM to measure accounts of the momentary experience of health in different populations is feasible. Retrospective measures may provide a biased account of the impact of health problems in the daily lives of people who are affected. Moreover, the bias may be different in different conditions.

Tinnitus: a cost study.

OBJECTIVES: The aim of this study was to examine the costs of tinnitus in The Netherlands from a health care and a societal perspective. Furthermore, the impact of disease characteristics and demographic characteristics on these costs were examined. METHODS: A bottom-up cost of illness study was performed, using the baseline data on a cost questionnaire of a randomized controlled trial investigating the (cost) effectiveness of an integral multidisciplinary treatment for tinnitus versus care as usual. Mean yearly costs were multiplied by the prevalence figure of tinnitus for the adult general population to estimate the total cost of illness of tinnitus to society. Because cost data usually are not normally distributed, a nonparametric bootstrap resampling procedure with 1000 simulations was performed to determine statistical uncertainty of the cost estimates per category. Several questionnaires measuring disease and demographic characteristics were administered. The impact of disease characteristics and demographics on costs was investigated using a multivariate regression analysis. RESULTS: Total mean societal cost of illness was €6.8 billion (95% confidence interval: €3.9 billion-€10.8 billion). The larger part of total cost of illness was not related to health care. Total mean health care costs were €1.9 billion (95% confidence interval: €1.4 billion-€2.5 billion). Significant predictors of both health care costs and societal costs were tinnitus severity, age, shorter duration of tinnitus, and more severe depression. CONCLUSION: The economical burden of tinnitus to society is substantial, and severity of tinnitus is an important predictor of the costs made by patients.

Tinnitus interferes with daily life activities: a psychometric examination of the Tinnitus Disability Index.

OBJECTIVES: Tinnitus Disability Index (TDI) is presented as a novel and brief self-report measure for the assessment of the interference of tinnitus with performance in specific daily life activities. We hypothesized that the TDI is a reliable and valid measure and that tinnitus disability is strongly associated with tinnitus severity, subjective tinnitus intensity ratings, and ratings of general health. DESIGN: Six hundred fifteen tinnitus patients from across the Netherlands completed online a number of questionnaires about their tinnitus, their general health, and demographics. Two samples were extracted by a random split: Sample I (N = 311) for exploratory factor analysis and Sample II (N = 304) for confirmatory analysis, using structural equation modeling. One hundred forty-three of the first included respondents repeated assessment after a 2-wk time interval for test/retest analysis. Regression analyses were employed to investigate construct validity. RESULTS: Present analyses reveal that tinnitus disability, as measured with the TDI, might be best understood as a single-component construct, that is, one single underlying factor. The TDI is reliable over time, and tinnitus-related disability, as measured with the TDI, is strongly associated with subjective ratings of tinnitus intensity, negatively associated with quality of life ratings, and distress due to tinnitus. CONCLUSIONS: The TDI is a brief and easily administered index measuring a unique construct, namely the experienced interference of the tinnitus with daily life activities, which is invaluable in the assessment and treatment of tinnitus patients.

Assessment of health state in patients with tinnitus: a comparison of the EQ-5D and HUI mark III.

OBJECTIVES: Expressing the outcomes of treatment in quality-adjusted life years is increasingly important as a tool to aid decision makers concerning the allocation of scarce resources within the health care sector. A quality-adjusted life year is a measure of life expectancy that is weighted by health-related quality of life. These weights are referred to as utility scores and are usually measured by multiattribute utility measures. Several studies found that different utility measures provide different estimates of the same person's level of utility. The aim of this study was to investigate which of two widely used utility measures, the EQ-5D and the HUI mark III, is preferred in a tinnitus population. METHODS: Baseline and follow-up data on EQ-5D and HUI mark III of 429 patients of a randomized controlled clinical trial, investigating cost-effectiveness of usual care versus specialized care of tinnitus, were included. Agreement, discriminative power, and responsiveness of the health state description and the utility scores were examined. RESULTS: Corresponding dimensions of the EQ-5D and HUI mark III showed large correlations; although ceiling effects were more frequently observed in the EQ-5D. Mean utility scores for EQ-5D (0.77; SD 0.22) and HUI mark III (0.64; SD 0.28) were significantly different (Wilcoxon signed ranks test, p < 0.001), and agreement was low to moderate (intraclass correlation coefficient = 0.53). Both health state description and utility scores of both measures discriminated between different severity groups. These groups were based on baseline scores of the Tinnitus Questionnaire. The HUI mark III had a higher ability than the EQ-5D to detect improved patients from randomly selected pairs of improved and unimproved patients. CONCLUSION: This study shows that different utility measures lead to different health state descriptions and utility scores among tinnitus patients. However, both measures are capable of discriminating between clinically different groups. The HUI mark III is more responsive than the EQ-5D, and therefore preferred in a tinnitus population.

Cost-effectiveness of specialized treatment based on cognitive behavioral therapy versus usual care for tinnitus.

OBJECTIVE: To evaluate the cost-effectiveness of specialized multidisciplinary tinnitus treatment based on cognitive behavioral therapy, compared with care as usual. DESIGN: Randomized controlled trial including an economic evaluation from a health-care and societal perspective, using a one-year time horizon. SETTING: Audiologic center. PATIENTS: A referred sample of 626 patients with tinnitus were eligible for participation. Approximately 492 patients were included in the study. Eighty-six (35%) of 247 patients in the usual care group, and 74 (30%) of 245 patients in the specialized care group were lost to follow-up by month 12. MAIN OUTCOME MEASURES: Quality adjusted life years (QALYs) as measured with the Health Utilities Index Mark III and cost in US dollars. RESULTS: Compared with patients receiving usual care, patients who received specialized care gained on average 0.015 QALYs (95% bootstrapped confidence interval [BCI], -0.03 to 0.06). The incremental costs from a societal perspective are $357 (95% BCI,-$1,034 to $1,785). The incremental cost per QALY from a societal perspective amounted to $24,580. The probability that SC is cost-effective from a societal perspective is 58% for a willingness to pay for a QALY of $45,000. CONCLUSION: Specialized multidisciplinary tinnitus treatment based on cognitive behavioral therapy is cost-effective as compared with usual care. Although uncertainty surrounding the incremental costs and effects is considerable, sensitivity analysis indicated that cost-effectiveness results were robust.