Abstract
Utility value is an important outcome for cost-utility analysis (CUA). The EQ-5D is used to elicit the utility values for economic analyses recommended by the Thai health technology assessment guideline. Therefore, this literature review was to establish the dataset of utility values for Thai patients with liver, lung, colorectal, breast, cervical, ovarian and hematologic cancers in various stages in Thailand.
This study reviewed all relevant studies by searching international databases such as PubMed and Scopus, and national databases including health intervention and technology assessment program (HITAP), health systems research institute (HSRI) and Thai LIS-Thailibrary integrated system (ThaiLIS) Study was included if 1) report utility values for Thai cancer patients and 2) identify the type of instruments used to elicit utility values. Moreover, quality scoring and assessment were performed for all included studies based on the adapted National Heart, Lung and Blood Institute guideline.
Of total 4,432 studies identified, 30 studies were included for literature review. Utility values were elicited from direct methods (Standard gamble; n=3 and mixed direct methods: Standard gamble, Time-trade off and Visual analog scale; n=1), indirect methods (n=14), mixed direct and indirect methods (n=3), mapping techniques (n=3), indirect method and retrieved from published papers (n=3) and unidentified methods (n=3). Within indirect methods, the EQ-5D questionnaire (n=17) was used in which the EQ-5D-3L (n=13) was the most frequently used. However, none of the included studies reported the psychometric performance of the instruments used to elicit the utility values.
This review establishes the dataset of utility values for Thai cancer patients with various stages. Both direct (SG, TTO and VAS) and indirect methods are used to elicit the utility values. The utility values decline in patients with metastatic stage (Stage IV) compared to the earlier-stage (Stage I-II). However, the utility values are mostly the result from chemotherapy or surgery for cancer treatment, so the utility values is directly uncomparable among the included studies. Therefore, further studies investigating the differences of utility values derived from direct and indirect methods among Thai patient cancers with various stages should be encouraged. Furthermore, the EQ-5D-5L with hybrid model should be used to elicit the utility values for economic analyses based on Thai health technology assessment guideline.
