Navigating Unserved Areas: A Comprehensive Review of Medical Deserts

Medical deserts have become an increasingly prominent expression of unequal access to healthcare, yet the literature addressing this phenomenon remains fragmented, with heterogeneous definitions, indicators, and analytical approaches. This narrative review aims to systematize existing evidence by developing and applying a multidimensional typology based on four analytical axes: medical specialty, geography, population vulnerability to threats, and systemic barriers. A narrative review of English-language studies retrieved from Web of Science, PubMed, Scopus, and Google Scholar was conducted and interpreted through this framework. The analysis shows that medical deserts are described across a wide range of clinical fields and territorial contexts, with research concentrating primarily on specialty- and geography-based dimensions. In contrast, population vulnerability and systemic barriers are addressed less consistently and are often treated implicitly rather than as core analytical dimensions. Vulnerable groups and structural determinants of access, including organizational, regulatory, and digital factors, remain underexplored despite their growing relevance. By organizing fragmented evidence into a coherent multidimensional framework, this review clarifies how medical deserts emerge as systemic phenomena and highlights the need for integrated policy responses that move beyond workforce redistribution to address social vulnerability and health system design.