Identifying key factors of medical service quality by a modified DEMATEL method based on total sensitivity analysis

Decision-making trial and evaluation laboratory (DEMATEL) has been widely used by practitioners to improve service quality as well as to increase customer satisfaction by identifying key factors. For an effective study, two-stage surveys are needed. First, conducting a survey is required in order to identify the important factors. A derived importance method is used if the information of importance is not available. Then, the DEMATEL questionnaire is designed and then conducted to collect the needed information. The traditional DEMATEL questionnaire completely uses self-stated assessments to evaluate the direct influence and total influences to identify critical factors. The disadvantages of using self-stated evaluation are that respondents might have hard time differentiating the differences between low level and high level of influences. In addition, social norms or political correctness might affect respondents' answers. This study introduces a total sensitivity index method based on information theory when the DEMATEL questionnaire is unavailable in the second stage. Moreover, an integrated framework of normalized mutual information and total sensitivity analysis in modified DEMATEL method is proposed with four steps. Finally, a case study of the national health of Xianxi Township which is located in Changhua County, Taiwan is illustrated to examine the medical service quality by the proposed framework when the DEMATEL questionnaire is unavailable directly from the survey.