Global trends and thematic evolution in online consultation with digital health technologies: Implications for future implementation and policy development

Online consultation has become a mainstream element of digital health within telemedicine, seeing rapid growth during the COVID-19 pandemic. Video, telephone, and secure messaging are extensively used for clinical advice, assessments, and follow-ups. However, the adoption of these technologies remains inconsistent, particularly in regions with limited infrastructure and workforce capacity. Key challenges include patient engagement, integration into clinical workflows, and the efficient allocation of resources. This bibliometric analysis covers 2,426 English-language journal articles indexed in the Science Citation Index Expanded (SCI-Expanded) within the Web of Science Core Collection (WoSCC) (1990-2025). Utilizing VOSviewer and the bibliometrix package, we mapped publication growth, international collaborations, keyword co-occurrence, and thematic evolution, with country-specific trajectories examined for the leading contributors. Countries were ranked via full counting, and joinpoint regression identified inflection points in annual publication output. Publication output grew steadily over the past 35 years, accelerating significantly after 2018, with a sharp peak from 2019 to 2022. The United States, England, China, Canada, Australia, and Germany were the main contributors and central hubs in international collaboration. The thematic focus shifted from early feasibility studies to service management, quality and outcome evaluation, barriers to implementation, equity considerations, and post-pandemic integration into standard care pathways. Country-specific trends were evident: the United States focused on telemedicine models and reimbursement mechanisms, England concentrated on primary care and general practice, and China experienced rapid growth in telehealth research post-2018. The literature on online consultation has evolved from proof-of-concept studies to a system-wide focus on management, evaluation, and large-scale implementation. These variations reflect differences in health system organization, regulation, reimbursement policies, and digital readiness across countries. Long-term reimbursement strategies, interoperable digital infrastructures, and equity-oriented service design may support the sustainable implementation of online consultation services.