Gravity models for potential spatial healthcare access measurement: a systematic methodological review

Area of Science:

• Healthcare access measurement
• Spatial analysis in public health
• Geographic Information Systems (GIS) in healthcare

Background:

• Quantifying spatial access to care, considering accessibility and availability, is crucial for healthcare planning and understanding service distribution.
• Numerous methods exist to measure potential spatial access to healthcare services.
• This study systematically reviews gravity model-type methods for spatial healthcare access measurement and their empirical applications.

Approach:

• A two-step systematic review following PRISMA guidelines.
• Identified methodological studies developing novel gravity models for healthcare access.
• Identified empirical studies applying these methods, using forward citation searching.

Key Points:

• The Two-Step Floating Catchment Area (2SFCA) and Kernel Density (KD) methods are major developments.
• The 2SFCA method family encompasses most novel methodologies, addressing distance decay, catchment areas, and transportation modes.
• Empirical studies predominantly use 2SFCA methods, often in their basic form, for descriptive purposes or as explanatory factors for health outcomes.

Conclusions:

• Gravity models for spatial healthcare access are overwhelmingly dominated by the 2SFCA method family in both development and application.
• Despite increasing methodological complexity in new developments, simpler, computationally feasible 2SFCA applications prevail in research practice.