Comparing health workforce forecasting approaches for healthcare planning: The case for ophthalmologists

Health workforce planning is essential in the provision of quality healthcare. Several approaches to planning are customarily used and advocated, each with unique underlying assumptions. Thus, a thorough understanding of each assumption is required in order to make an informed decision on the choice of forecasting approach to be used. For illustration, we compare results for eye care requirements in Singapore using three established workforce forecasting approaches – workforce-to-population-ratio, needs based approach, utilization based approach – and a proposed robust integrated approach to discuss the appropriateness of each approach under various scenarios. Four simulation models using the systems modeling methodology of system dynamics were developed for use in each approach. These models were initialized and simulated using the example of eye care workforce planning in Singapore, to project the number of ophthalmologists required up to the year 2040 under the four different approaches. We found that each approach projects a different number of ophthalmologists required over time. The needs based approach tends to project the largest number of required ophthalmologists, followed by integrated, utilization based and workforce-to-population ratio approaches in descending order. The four different approaches vary widely in their forecasted workforce requirements and reinforce the need to be discerning of the fundamental differences of each approach in order to choose the most appropriate one. Further, health workforce planning should also be approached in a comprehensive and integrated manner that accounts for developments in demographic and healthcare systems.