New trial in Nigeria evaluates voice-based hotline that connects rural health care workers to the power of generative AI
Community health extension workers are testing the performance of a toll-free platform that uses large language models to deliver on-demand, expert-level responses to their diagnosis and treatment questions.
Adedeji Christianah, a community health extension worker at Oke-Itunu Primary Health Centre in Oyo State, Nigeria, uses Community Health Extension Worker Assistant, a generative artificial intelligence tool, while consulting with a patient. Photo: Viamo.
PATH and Viamo, a Canadian social enterprise, have launched a groundbreaking trial that will provide critical insights into how health care workers who lack access to a computer, smartphone, or internet connection can still benefit from artificial intelligence (AI)–enabled clinical decision support tools. Community health extension workers (CHEWs) in two Nigerian states, Kano and Oyo, will utilize a toll-free hotline that uses generative AI (GenAI) to deliver verbal responses to their health-related queries. This platform—Community Health Extension Worker Assistant (CHEWA)—uses voice prompts to give CHEWs on-demand access to a GenAI capability that provides contextually appropriate medical guidance, all from a basic phone via a simple voice call.
PATH and Viamo are conducting this research study with a consortium of partners, including the Association for Reproductive and Family Health, the University of Birmingham, Obafemi Awolowo University, and the Centre for Research, Evaluation Resources and Development (CRERD).
CHEWs are health professionals who play a critical role in delivering frontline health care. With physicians and other experts highly concentrated in urban areas, CHEWs are charged with making diagnosis and treatment decisions across a wide range of health concerns in their rural communities. Their ability to make timely and accurate diagnoses is often hindered by their limited medical training and their inability to reach experts for consultations when they encounter complex or unfamiliar medical cases. Many lack access to smart devices or the internet, instead relying on their personal mobile handset.
“Advancements in voice-first GenAI present a new opportunity to support CHEWs in delivering accurate, timely, and comprehensive health care,” said Charles Ohikhuai, Head of Programs at Viamo Nigeria. “By providing real-time, contextually appropriate information, the CHEWA could help community health extension workers overcome existing barriers in accessing medical knowledge.”
“Advancements in voice-first GenAI present a new opportunity to support community health extension workers (CHEWs) in delivering accurate, timely, and comprehensive health care.”— Charles Ohikhuai, Head of Programs, Viamo Nigeria
To ensure patient safety during the trial, the team will monitor CHEWs’ use of the AI knowledge assistant through a real-time dashboard. A panel of medical experts will review transcripts within the hour on the same day of the CHEW interactions with the platform to ensure it is providing responses that are safe, accurate, and in compliance with Nigeria’s national medical guidelines. If a response provided by the CHEWA platform is flagged as unsafe or potentially harmful, the CHEW who receives that guidance will receive a follow-up call from a medical expert with the correct information and will follow established protocols to reach the patient to correct the diagnosis and treatment plan.
“Our research design allows us to build trust with CHEWs and their patients by ensuring that the AI tool will provide safe, actionable, and context-relevant guidance,” said Dr. Elizabeth Omoluabi, Director at CRERD. “At the end of the study, we will have generated much-needed evidence about how AI-enabled clinical decision tools can be designed to best support frontline health care workers and be effectively harnessed to improve health service delivery for all Nigerians.”
“At the end of the study, we will have generated much-needed evidence about how AI-enabled clinical decision tools can be designed to best support frontline health care workers.”— Dr. Elizabeth Omoluabi, Director at CRERD
Patient recruitment began on June 26, 2025, and will run until CHEWA logs approximately 3,000 patient encounters. One hundred CHEWs will participate in this first research phase. When using the platform, CHEWs will also be asked to respond to a satisfaction survey to provide feedback on the user experience and their perceived quality and usefulness of the medical guidance provided. These data will be used to inform improvements to the CHEWA platform and future research on and rollout of voice-based AI-enabled tools for frontline health care workers.
“For too long, we’ve merely talked about the evidence gap around the effectiveness of AI-based solutions in low-resource health care settings. It’s a privilege to be able to do something about it,” said Bilal Mateen, Chief AI Officer at PATH. “It’s especially exciting to be able to generate evidence on such an innovative tool that bypasses the major hurdle of internet connectivity at the last mile, helping us genuinely touch the lives of those in rural communities.”
“For too long, we’ve merely talked about the evidence gap around the effectiveness of AI-based solutions in low-resource health care settings. It’s a privilege to be able to do something about it.”— Bilal Mateen, Chief AI Officer at PATH
About PATH
PATH is a global nonprofit dedicated to achieving health equity. With more than 40 years of experience forging multisector partnerships, and with expertise in science, economics, technology, advocacy, and dozens of other specialties, PATH develops and scales up innovative solutions to the world’s most pressing health challenges. The first-ever Phase 3 randomized controlled trial of a large language model–based clinical decision support tool in Africa is currently being led by PATH and its partners in Kenya.
For media inquiries, please contact Lauren Grella, Senior Director of Marketing and Communications, at media@path.org.
About Viamo
Viamo is a technology social enterprise. Its platform provides the connection to spark life-changing information exchanges with millions of people with access to a simple mobile phone but no internet connection, offering services for the international development and business sectors. Globally, its platform reached 27.2 million active users, consuming more than 652 million messages in 72 languages in 2024 alone.
About the Centre for Research, Evaluation Resources and Development
The Centre for Research, Evaluation Resources and Development (CRERD) is a nonprofit, nongovernmental organization concerned with improving the understanding and delivery of population and health services and environmental development in Nigeria and other countries in Africa. The organization is an outgrowth of the Operations Research Unit and Network, Obafemi Awolowo University, lIe-lfe.