Biomedical subjects

M G Hunink

Publications and source records attributed to M G Hunink.

59 records · Page 4Linked to original sources

PubMedDate not supplied

Heterogeneity in the relationship between the standard-gamble utility measure and health-status dimensions.

The authors assessed the relationship between the standard-gamble utility measure and the RAND-36 health-status dimensions, taking into account possible heterogeneity among patients in the weights they assign to different health-status dimensions. A questionnaire including both measures was completed by 68 patients with symptomatic peripheral arterial disease. Conventional multiple regression analysis, assuming a homogeneous relationship for the total population between the standard-gamble utility and the RAND-36 health-status dimensions, demonstrated that only the dimension social functioning was significant (p < 0.05), which accounted for 10% of the variation. Assuming that the population consisted of two separate classes demonstrated superior representation of the data. Latent class analysis was used to estimate the unknown parameters and class memberships. In the first class, consisting of 65% of the patients, the relationship between the standard-gamble utility and the dimension general health perception was significant. The within-R2 was 12%. The second class represented 35% of the patients and showed significant coefficients for the dimensions social functioning and role limitations due to physical problems, which accounted for 80% of the variation. The overall percentage of variation explained by latent class analysis was 49%. The results suggest that patients with symptomatic peripheral arterial disease belong to a variety of classes, all with class-specific relationships between the standard-gamble utility and the RAND-36 health-status dimensions.

Activities of Daily Living↗

PubMedDate not supplied

Fitting multistate transition models with autoregressive logistic regression: supervised exercise in intermittent claudication.

The purpose of this study was to develop a model that predicts the outcome of supervised exercise for intermittent claudication. The authors present an example of the use of autoregressive logistic regression for modeling observed longitudinal data. Data were collected from 329 participants in a six-month exercise program. The levels of the polytomous outcome variable correspond to states they defined in a Markov decision model comparing treatment strategies for intermittent claudication. Autoregressive logistic regression can be used to fit multistate transition models to observed longitudinal data with standard statistical software. The technique allows exploration of alternative assumptions about the dependence in the outcome series and provides transition probabilities for different covariate patterns. Of the alternatives examined, a Markov model including two preceding responses, time, age, ankle brachial index, and duration of disease best described the data.

Decision Support Techniques↗

PubMedDate not supplied

Uncertainty in decision models analyzing cost-effectiveness: the joint distribution of incremental costs and effectiveness evaluated with a nonparametric bootstrap method.

PURPOSE: To illustrate the use of a nonparametric bootstrap method in the evaluation of uncertainty in decision models analyzing cost-effectiveness. METHODS: The authors reevaluated a previously published cost-effectiveness analysis that used a Markov model comparing initial percutaneous transluminal angioplasty with bypass surgery for femoropopliteal lesions. Each probability in the model was simulated with a first-order Monte Carlo simulation to represent sampling uncertainty. Superimposed on this, a second-order Monte Carlo simulation was performed to represent parameter uncertainty, drawing the probability values from nonparametric distributions based on published data or from primary collected data as available. After simulation of a mixed (i.e., non-identical) cohort of 30,000 patients, 3,000 bootstrap samples of 1,000 patients each were drawn and the joint distribution of mean incremental costs and mean effectiveness gained was evaluated. RESULTS: Using a bootstrap sample size of 1,000 patients, 92.7% of the joint distribution of mean incremental costs and mean effectiveness gained fell in the quadrant where angioplasty dominated bypass surgery. Another 6.9% of samples demonstrated either greater effectiveness with an incremental cost-effectiveness ratio of at most $20,000/QALY gained, or cost savings with a ratio of at least $20,000 saved/QALY lost. CONCLUSION: A nonparametric bootstrap method can be used to estimate the joint distribution of mean incremental costs and mean effectiveness gained, and the results can provide an understanding of the uncertainty in a cost-effectiveness analysis based on a decision model.

Angioplasty, Balloon↗

PubMedDate not supplied

Estimating general-population utilities using one binary-gamble question per respondent.

This study used a single binary-gamble question per health state per respondent to obtain societal preferences for the health states intermittent claudication and major amputation and compare those with Health Utilities Indices obtained from patients, to test the feasibility of this method, and to investigate whether the utility depends on the presentation of a vignette as generic vs disease-specific. A random sample of the general U.S. population (n = 1,003) was randomly divided into ten subgroups. In telephone interviews, subjects answered one binary-gamble question in a standard-gamble format for each of two health states. The risks of death varied across subgroups but not between health states. Mean utility was estimated by the area above the proportional distribution of responses indicating acceptance of the gamble. The method is based on the binary-choice method used in contingent-valuation studies of willingness to pay. The health states were alternatively described by generic and disease-specific vignettes in two subsamples. The results suggest that the binary-gamble question can be used to obtain societal preferences for health states, and that disease-specific descriptions yield lower utilities compared with generic descriptions of health states.

Adult↗

PubMedDate not supplied

Time-tradeoff values and standard-gamble utilities assessed during telephone interviews versus face-to-face interviews.

The purpose of this study was to compare time-tradeoff values and standard-gamble utilities obtained during telephone interviews with those obtained through face-to-face interviews. Sixty-five patients with peripheral arterial occlusive disease completed both interviews. One week prior to the telephone interview, the patients received by mail a questionnaire in which the value and utility measures were presented in writing. The face-to-face interviews used the same questions, but the interviewer used visual aids. The mean time-tradeoff values were 0.84 (SD 0.20) vs 0.86 (SD 0.17) for the telephone and face-to-face interviews, respectively (p = 0.31). The mean standard-gamble utilities were 0.93 (SD 0.16) vs 0.92 (SD 0.17) for the telephone and face-to-face interviews, respectively (p = 0.26). In conclusion, telephone interviews yield similar time-tradeoff values and standard-gamble utilities compared with face-to-face interviews, suggesting that telephone interviews can replace face-to-face interviews.

Adult↗