%0 Journal Article
%T An empirical comparison of methods for analyzing correlated data from a discrete choice survey to elicit patient preference for colorectal cancer screening
%A Ji Cheng
%A Eleanor Pullenayegum
%A Deborah A Marshall
%A John K Marshall
%A Lehana Thabane
%J BMC Medical Research Methodology
%D 2012
%I BioMed Central
%R 10.1186/1471-2288-12-15
%X A two-stage DCE design was used to investigate the impact of six attributes on participants' preferences for CRC screening test and willingness to undertake the test. We compared six models for clustered binary outcomes (logistic and probit regressions using cluster-robust standard error (SE), random-effects and generalized estimating equation approaches) and three models for clustered nominal outcomes (multinomial logistic and probit regressions with cluster-robust SE and random-effects multinomial logistic model). We also fitted a bivariate probit model with cluster-robust SE treating the choices from two stages as two correlated binary outcomes. The rank of relative importance between attributes and the estimates of ¦Â coefficient within attributes were used to assess the model robustness.In total 468 participants with each completing 10 choices were analyzed. Similar results were reported for the rank of relative importance and ¦Â coefficients across models for stage-one data on evaluating participants' preferences for the test. The six attributes ranked from high to low as follows: cost, specificity, process, sensitivity, preparation and pain. However, the results differed across models for stage-two data on evaluating participants' willingness to undertake the tests. Little within-patient correlation (ICC ¡Ö 0) was found in stage-one data, but substantial within-patient correlation existed (ICC = 0.659) in stage-two data.When small clustering effect presented in DCE data, results remained robust across statistical models. However, results varied when larger clustering effect presented. Therefore, it is important to assess the robustness of the estimates via sensitivity analysis using different models for analyzing clustered data from DCE studies.With increased emphasis on the role of patients in healthcare decision making, discrete choice experimental (DCE) designs are more often used to elicit patient preferences among proposed health services programs [1,2]. DC
%K Discrete choice experiment
%K Intra-class correlation
%K Statistical model
%K Patient preference
%U http://www.biomedcentral.com/1471-2288/12/15