METHODS: Literature and government documents were reviewed and analyzed by authors with experiences in HTA and drug policy in the country.

RESULTS: The structure of HTA and its process in the drug selection of the NLEM were described, followed by the outcomes of the use of HTA. Examples of lowering drug prices, as a result of price negotiation using HTA, were presented. A few examples were also provided to demonstrate how decisions were made from considering factors beyond cost-effectiveness findings. Finally, challenges on various issues including improvement of HTA structure and process were discussed for the future direction of HTA in Thailand.

METHODS: We conducted systematic search in PubMed and Scopus from September 1, 2016, to July 22, 2022. Original COI studies estimating the economic cost of obesity and/or overweight in at least one country, published in English were included. To facilitate the comparison of estimates across countries, we converted the cost estimates of different years to 2022 purchasing power parity (PPP) values using each country's consumer price index (CPI) and PPP conversion rate.

RESULTS: Nineteen studies were included. All studies employed a prevalence-based approach using Population Attributable Fraction (PAF) methodology. About half of the included studies (53%) were conducted in high-income countries while the others (47%) were conducted in middle-income countries. The economic burden of obesity ranged between PPP 15 million in Brazil to PPP 126 billion in the USA, in the year 2022. Direct medical costs accounted for 0.7% to 17.8% of the health system expenditure. Furthermore, the total costs of obesity ranged from 0.05% to 2.42% of the country's gross domestic product (GDP). Of the seven studies that estimated both direct and indirect costs, indirect costs accounted for the largest portion of five studies. Nevertheless, a variety in methodology across studies was identified. The number of co-morbidities included in the analysis varied across studies.