Background: Disparities in MR access between different countries and healthcare systems are well documented. Determinants of unequal access within the same healthcare system and geographical region are poorly understood.
Objective: An analysis of public sector MR utilisation in South Africa's Western Cape province (WCP).
Methods: A retrospective study of WCP MR and population data for 2013 and 2018. MR units/106 people, studies, and studies/103 people were calculated for each year, for the whole province and the 'western' and 'eastern' referral pathways, stratified by age (0-14 years, > 14 years).
Results: Between 2013 and 2018, the WCP population increased 8% (4.63 vs 5.08 × 106 people) while MR resources were unchanged ('western' = 2 units; 'eastern' = 1), equating to decreasing access (units/106 people) for the province (0.65 vs 0.59; -9.2%), the 'western' (0.97 vs 0.9; -7.2%) and 'eastern' (0.39 vs 0.35; -10.3%) pathways. In 2013, 40% (4005/10 090) of studies were in the 'eastern' pathway serving 55% (2 066 079/4 629 051) of the population. Between 2013 and 2018 'eastern' population growth (n = 286 781) exceeded 'western' (n = 168 469) by 70% (n = 118 312). By 2018, 38% (7939/12 848) of studies were performed in the 'eastern' pathway, then serving 56% (2 849 753/5 084 301) of the population. Among 0-14-year-olds, 'western' utilisation (studies/103 people) exceeded 'eastern' by a factor of approximately 2.4 throughout. In patients > 14 years, the utilisation differential increased from 1.78 to 1.98 in the review period.
Conclusion: Ensuring equitable services on the same healthcare platform requires ongoing surveillance of resource and population distribution. MR access can serve as a proxy for equity in highly specialised services.