Clinical Evaluation of Pediatric Pulse Oximeters in South Africa: Protocol for a Cluster Randomized Controlled Trial

The burden of children with lower respiratory infections and low blood oxygen levels (hypoxemia) is high, and outcomes are poor in low- and middle-income countries (LMICs). Pulse oximeters noninvasively measure the capillary oxyhemoglobin saturation (SpO2) to identify hypoxemia, but high-quality devices designed for the unique needs of children are rarely available in primary health care clinics (PHCs) in LMICs, where children initially access care.

This study aims to evaluate whether 2 pediatric pulse oximeters co-designed with health care workers (HCWs) in LMICs improve the correct SpO2 management of children in PHCs compared to a standard pulse oximeter.

We are conducting a pragmatic 3-arm cluster randomized controlled trial in the Eastern Khayelitsha, Northern, and Tygerberg areas of Cape Town, South Africa, over 18 months between 2024 and 2026. We plan to enroll 1200 children aged younger than 2 years with an acute respiratory infection from 18 PHCs randomized to implement one of 3 pulse oximeters, either 1 standard-of-care device or 2 intervention devices. HCWs in selected PHCs will administer the intervention. Our primary outcome will be "correct SpO2 management," an intermediate clinical end point between device implementation and hypoxemia outcome, defined by the following three elements necessary to reduce inappropriately treated hypoxemia: (1) device adoption-HCW use of the device as evidenced by a HCW-documented SpO2 and pulse rate; (2) quality SpO2 measurement-SpO2 confirmed by reference device measurement within 2% SpO2 above or below the HCW-measured SpO2; and (3) correct SpO2 decision-making-an appropriate referral recommendation by the HCW. A concurrent mixed methods process evaluation will explore how, why, for whom, and to what extent these devices impact the clinical management of hypoxemic children. The primary analysis will be intention-to-treat. For all primary and secondary outcomes, we will conduct pairwise comparisons between the 2 intervention arms and the control arm.

Data collection commenced in 2024, and results are expected from 2026 to 2027. As of December 2025, enrollment has been completed in 12 clinics.

While there are notable challenges inherent in designing a trial to evaluate whether pulse oximeters improve HCW SpO2 management of children at PHCs, our protocol development process attempted to address all potential limitations and sources of bias to maximize the trial's future impact.