Measuring the contact coverage of maternal, newborn, child, and adolescent health (MNCAH) services overestimates the benefits of these services because the quality of care provided during a contact is not measured.

Effective coverage measures the proportion of the population that received a service with sufficient quality to have a positive health outcome from the service.

MNCAH services and interventions involve a series of complex interactions between patients and the health system that are best measured using health service coverage cascades that follow an individual through their care journey to identify where efficiency is lost.

Current data limitations and gaps make measuring effective coverage using health service cascades challenging. Further investment in data collections and measurement methods is required so that the method can be used at both the facility and population levels.

We argue that using these cascades for global monitoring for MNCAH is premature and make recommendations for how to scale up use of health service coverage cascades for global monitoring.

As countries take on the challenge of meeting the Sustainable Development Goal targets for health (SDG 3)1 by 2030, they are monitoring a range of indicators, including those measuring coverage of essential health services for women, newborns, children, and adolescents. Existing coverage indicators measure service contact coverage or intervention coverage,2 that is, the proportion of the target population that either reaches an appropriate health service or receives the required intervention.

Within the context of this viewpoint, a health service is referred to as a system or organized effort aimed at providing health care to individuals or populations and that encompasses a wide range of components, including the infrastructure, personnel, resources, and processes necessary to deliver care (e.g., inpatient or outpatient services and emergency services).3 In contrast, a health intervention is a specific action or set …