Cost-effectiveness of multi-sample National Thalassemia Screening Programme vs. single-sample reflex DNA thalassemia screening in Malaysian schools: a comparative study in Sabah and Sarawak

Background: Thalassemia poses a significant health and financial burden in Malaysia, highlighting the need for effective screening strategies to reduce the incidence of severe cases and associated costs. While the National Thalassemia Screening Programme (NTSP) for students has made progress in identifying carriers, challenges persist in preventing dropouts and ensuring timely diagnoses. This study assessed the cost-effectiveness of thalassemia screening and prevalence reduction using the single-sample reflex DNA approach comparing Sabah and Sarawak for Form Four or 16-year-old school adolescents. The existing National Screening approach (P1) uses multi-sample compared to the single-sample reflex DNA approach (P2), considering cost, effectiveness, potential cost savings on treatment expenses, and prevalence reduction. Methods: The study employed a retrospective quantitative approach, using secondary data and nonprobability sampling techniques. A purposive sampling method was used to select two states with contrasting prevalence levels: Sabah, with a prevalence rate above the national average, and Sarawak, with a lower-than-average prevalence. The sample comprised 36,860 test cases from Sabah and 35,161 from Sarawak, enabling a comparative analysis of the cost-effectiveness of P1 and P2. We conducted the analysis in three stages: (I) calculating screening and diagnosis costs, (II) comparing dropout rates and carriers identified under each approach, and (III) projecting the long-term impact on future treatment cost savings and prevalence reduction. Results: The cost-effectiveness analysis using the incremental cost-effectiveness ratio (ICER) demonstrated that the additional cost per dropout averted was around RM 40. However, further analysis revealed substantial potential savings in future treatment costs associated with P2, suggesting significant savings for both Sabah and Sarawak. Depending on the assumed 2% to 6% probability of carriers marrying each other, the projected savings range from RM 691,000 to RM 11 million in Sabah and RM 200,000 to RM 2.2 million in Sarawak, based on the estimated reduction in new thalassemia births. Additionally, the study forecasts a potential 40% annual decrease in thalassemia cases, with the possibility of achieving minimal to zero new cases within 15 years of sustained implementation. Conclusions: The single-sample reflex DNA approach is a cost-effective alternative to the existing NTSP. It offers a more efficient and rapid screening process, reducing dropout rates and time to diagnosis. Implementing this approach could enhance the screening program’s efficiency and contribute to reducing thalassemia prevalence in Sabah and Sarawak, providing a potential model for nationwide adoption.