Quality of Life Measurement and Its Application in Indonesia

This Ph.D. thesis entitled ‘Quality of life measurement and its application in Indonesia’ sets out to provide valid and reliable HRQOL measurement tools, namely EQ-5D-5L and WHOQOL-BREF to be used in Indonesia, including their population norms and a national value set for EQ-5D-5L. A standardized data collection procedure (EuroQol Valuation Technology/EQ-VT) and state-of-the-art quality control (QC) tool were implemented to obtain data from a representative sample of the Indonesian general population.
Six main findings of this thesis are the following:
(i) comprehensive training before and during the study, and individual feedback on the basis of a QC tool would increase the validity of values obtained;
(ii) the two EQ-5D-5L health states elicitation techniques employed in the EQ-VT: Time Trade-Off (TTO) and Discrete Choice Experiments (DCE) have different results concerning their test-retest reliability: the TTO is stable over time, while for DCE the relative values of the dimensions shift;
(iii) the Indonesian EQ-5D-5L value set was estimated by combining TTO and DCE data using so-called a ‘hybrid regression model’. It was shown that the preference of the Indonesian people were most affected by the mobility dimension and least by the pain/discomfort dimension and health states values were ranged from -0.865 for the worst state (‘55555’) to 1.00 for the health state with no problems in all dimensions (health state ‘11111’);
(iv) the EQ-5D-5L descriptive system and the WHOQOL-BREF questionnaire have acceptable test-retest reliability scores;
(v) the two questionnaires were able to differentiate between different sociodemographic characteristics: i.e., residence (urban/rural), gender, level of education, and income; and
(vi) the two questionnaires can differentiated the health status and quality of life of people living on the riverbanks of a highly polluted river and the Indonesian general population. The EQ-5D-5L and WHOQOL-BREF, together with its value set and population norms are now available in Indonesia and will promote and facilitate health economic evaluations and HRQOL research in Indonesia.