Economic evaluation of hepatitis A vaccines by income level of the country: A systematic review

Background & objectives: Although several reviews of economic evaluation (EE) studies on hepatitis A virus (HAV) vaccine exist, there remains a need to corroborate such data from time to time. This study aimed to systematically review the literature for reports on EE of HAV vaccination by type of population, characteristics of intervention and income level of the country. Methods: PubMed and Scopus were searched to identify relevant studies from inception up to May 2021 using topic-specific key words in various combinaiton. Full EE studies comparing HAV vaccination to no vaccine or immunoglobulin were included. The risk of bias was assessed by using the ECOBIAS checklist. Results: Among the 1984 identified studies, 43 were found eligible. Of these, 27 were from high-income countries (HICs), 15 from middle-income countries (MICs), and one from low income country. Majority of the studies used Markov model and/or decision tree (n=26). Eight studies used a dynamic model. The discount rate, perspective and time horizon varied across the studies. Universal HAV vaccination without screening was cost-effective among children (14/16, 87.5%) and adolescents (1/5, 20%) but not in adults (0/4, 0%). Analysis by the level of income found that universal HAV vaccination among children without screening was cost-effective in 81.8 per cent of the studies conducted in MICs (9/11) as compared to 66.7 per cent in HICs (4/6). About one-third of the studies conducted among children found that screening and HAV vaccination were cost-effective compared to no vaccination. Interpretation & conclusions: The finding of this review suggest that universal vaccination of children without screening was likely to be cost-effective, especially in MICs. Nevertheless, it should be noted that the methodology varied across studies. Several aspects should also be considered in transferring the EE results across jurisdictions.

A determination of topics for health technology assessment in Thailand: making decision makers involved.

This study is to describe experiences and findings from the topic selection process for health technology assessment (HTA) conducted by Health Intervention and Technology Assessment Program. The process comprised of 5 stages namely: (1) determining objectives, scope and involved stakeholders; (2) requesting potential topics for assessment from decision makers at the national health authorities; (3) reviewing related literature on and prioritizing the proposed HTA topics by HITAP researchers; (4) selecting the HTA topics by decisionmakers; (5) analyzing the strengths and weaknesses of the current topic selection processes by HITAP staff The strengths of the topic selection were systematic and transparent. It also required participation from stakeholders; however the limitations were topics prioritization methods and time constraints. Lessons learnt from this procedure can be useful for improving the next HTA topic selection in order to increase the usefulness of the future HTA results.

Measurement of clinical effects.

The measurement and valuation of clinical effects is a significant component of economic evaluation. Decision makers are commonly interested in how a particular health intervention works in everyday practice; therefore, the resulting outcome under this circumstance is called the effectiveness. Clinical effects usually measure final intended effects of a proposed health technology in terms of the ultimate change in health state brought about by the technology. The systematic review and meta-analysis of high quality RCTs is the most favorable method to synthesize evidence because they are disciplined and transparent methods. The present chapter focuses on how to make a valid measure of clinical effects for use in cost-effectiveness analysis and how clinical effect is to be appropriately defined and measured.

Making health technology assessment information available for decision making: the development of a Thai database.

In Thailand, there is an attempt to develop the Thai HTA database in order to improve the accessibility and usefulness of HTA information. At present, the database is available online at www.db.hitap.net. The database includes (1) economic evaluation studies i.e. cost-minimization analysis, cost-effectiveness analysis, cost-benefit analysis, and cost-utility analysis, (2) outcome assessment studies i.e. randomized controlled trials, and (3) quantitative measured quality of life studies. All HTA studies related to the Thai context, and published in either Thai or English from 1990 onward, are eligible for inclusion in the database. In addition, there is a quality evaluation for each economic evaluation study which will help readers, who have limited knowledge about the method, to understand and make appropriate use of the information in their own settings. This may also raise awareness among researchers, who will conduct economic evaluation studies in the future, to adhere to the standard methodological guidelines because the quality evaluation was developed based on the national guidelines published in this supplement journal.