An Economic Evaluation of the LINKEDin study: An intervention to reduce initial loss to follow-up among tuberculosis patients in South Africa

Tuberculosis (TB) patients who are diagnosed but not registered and initiated on TB treatment are categorised as initial loss to follow-up (ILTFU). ILTFU is a key driver of morbidity and mortality associated with TB and is a contributing factor to high TB transmission rates. LINKEDin was a quasi-experimental study which evaluated two specific interventions for reducing ILTFU in three high-TB burden provinces in South Africa. As part of LINKEDin, we undertook a micro-costing from the healthcare provider perspective using an activity-based costing approach. Cost estimates included the cost of the operation of an integrated provincial health data centre in the Western Cape, apportioned to the TB activities it supported in the province. Cost estimates were linked to intervention outcomes to understand the incremental cost of the intervention per additional patient linked to care compared to rates of ILTFU in the absence of the interventions. Sensitivity analyses were conducted to account for uncertainty in the intervention outcomes, and for periods where the implementation of the intervention was interrupted due to COVID-19 related disruptions. The primary cost driver of the interventions were staff salaries, with the cost of data extraction and in-hospital activities low relative to primary healthcare (PHC)-based follow-up activities. In the Western Cape, systematically tracking persons with TB using an automated system proved highly cost efficient compared to the more labour intense approach adopted in KwaZulu-Natal. Optimising the curation and management of data and increasing the effectiveness of tracing systems and processes can result in cost-savings.确诊后未进行登记且未启动结核治疗的结核病（Tuberculosis, TB）患者被归类为初始失访（Initial Loss to Follow-up, ILTFU）。初始失访是结核病相关发病与死亡的关键驱动因素，也是推高结核病传播率的重要诱因。LINKEDin是一项准实验研究，旨在评估南非三个结核病高负担省份中两种可降低初始失访率的特定干预措施。作为LINKEDin研究的组成部分，本研究从医疗服务提供方视角出发，采用基于活动的成本核算方法开展微观成本测算，成本测算范围涵盖西开普省一体化省级医疗数据中心的运维成本，并将该成本分摊至该中心在省内支持的各项结核病相关工作；将成本测算结果与干预结局进行关联，以对比无干预措施时的初始失访率，计算每额外成功衔接诊疗的患者所需的干预增量成本。针对干预结局的不确定性以及因新冠疫情相关干扰导致干预实施中断的时段，本研究开展了敏感性分析。本次干预措施的主要成本驱动因素为人员薪酬，相较于基于基层医疗（Primary Healthcare, PHC）的随访工作，数据提取与院内活动的成本相对较低。在西开普省，相较于夸祖鲁-纳塔尔省采用的劳动密集型方案，使用自动化系统系统性追踪结核病患者的方式被证实具备极高的成本效益。优化数据整理与管理工作，提升追踪系统及流程的效能，可实现成本节约。