Cost-Effectiveness of the IMPALA Monitoring System for Hospitalised Children in Low-Resource Settings: A Pragmatic Before-and-After Study
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Background
Staff shortages, limited training, and inadequate hospital equipment often delay responses to patient deterioration in low-resource settings. The IMPALA continuous monitoring system was developed to support proactive care for critically ill children in such settings. This study evaluated IMPALA cost-effectiveness compared with current practice manual intermittent monitoring from provider and societal perspectives.
Methods
We conducted an economic evaluation based on a before-and-after cohort of children (0 to 180 months) admitted to Zomba Central Hospital (ZCH) and St. Lukes Hospital (SLH), Malawi (2022 to 2024), where IMPALA was implemented in high-dependency units (HDUs). Targeted maximum likelihood estimation assessed percentage point (pp) differences in mortality, critical illness events (CIEs), disability-adjusted life years (DALYs), and costs (medical, non-medical, indirect). Incremental cost-effectiveness ratios (ICERs) and cost-effectiveness probabilities were calculated for different willingness-to-pay thresholds.
Findings
At ZCH paediatric ward, 1 840 pre- and 6 255 post-IMPALA children were included; 248 and 736 were admitted to the HDU. Ward mortality decreased (3.7% to 2.8%), with an adjusted 1.9pp reduction (95%CI: - 3.8;-0.6). At ZCH-HDU, mortality slightly increased (8.1% to 9.0%), but IMPALA was associated with an adjusted 9.8pp reduction (95%CI: -26.5;5.0), a 47.1pp decrease in CIEs (95%CI: -52.9;-41.8), and 5.4 DALYs averted (95%CI: -14.2;3.1). At SLH paediatric ward, mortality decreased (4.0% to 2.1%), with an adjusted 1.6pp reduction (95%CI: -3.2;-0.2), a 25.5pp decrease in CIEs (95% CI: -30.1;-20.9), and 1.0 DALYs averted (95% CI: -1.9;-0.1). Provider and societal costs decreased in both wards, but not in the HDU. IMPALA was dominant in wards and slightly more costly but more effective in the HDU (ICERs -$22.5 to $0.4 per life saved). Cost-effectiveness probabilities ranged from 0.8 to 1.0 in wards and 0.3 to 1.0 in the HDU.
Interpretation
IMPALA was highly cost-effective, reducing mortality by >40%, morbidity by >50%, increasing DALYs averted, shortening hospital stays, and lowering costs, with spillover benefits from HDUs to wards.
Funding
This project is part of the EDCTP2 programme (grant number RIA2020I-3294 IMPALA) supported by the European Union and Founders Pledge through GOAL3.
Evidence before the study
Continuous monitoring reduces mortality in high-resource settings, but its effectiveness in low-resource contexts remains uncertain. Systems designed for well-resourced environments may not suit settings with high patient-to-staff ratios, power instability, and limited supplies. In Malawi, qualitative findings suggest that the IMPALA monitoring system – including battery-supported automated digital continuous monitoring devices and local server, a tablet decision support app, and staff training – is feasible and potentially beneficial. However, evidence on the potential impact and cost-effectiveness are lacking.
Added value of this study
This study provides empirical evidence that the IMPALA monitoring system is a cost- and life-saving alternative to standard care, which relies on manual intermittent monitoring in low-resource settings. The findings indicate benefits, including saving lives, preventing critical illness events, and reducing disease burden, while lowering inpatient and societal costs by shortening hospital stays on paediatric wards as a spillover effect.
Implications of all the available evidence
This study implies that robust, well-implemented continuous patient monitoring systems can enhance children’s health outcomes and quality of care while reducing costs in a low-resource setting, highlighting the need for its broader implementation to improve paediatric care worldwide.
