GP locums are more likely to be young males and work in underperforming practices or in rural areas, according to a new study.

Analysis by researchers at the University of Manchester found that although the proportion of locums has not changed significantly between 2017 and 2020 – at 3% – usage of locums varied significantly between regions and clinical commissioning group areas.

Writing in the latest edition of the British Journal of General Practice, the researchers say they wanted to analyse national GP workforce data between December 2017 and September 2020 to determine the volume and geographical distribution of locum use and to examine the characteristics of locums compared with other GP types.

They modelled locum full-time equivalent (FTE) and estimated incidence rate ratios (IRRs) for associations between outcome and characteristics of practices and population. Although some practices did not provide valid or complete records, and this resulted in some data being recorded as missing or estimated, they point out that coverage was very high with about 95% of all practices providing valid workforce data in December 2019.

The FTE for locum GPs was derived as an average of the total number of hours worked in each month over the reporting quarter. They found practices in London had the highest locum FTE rate, while those in the Northeast and Yorkshire had the lowest locum FTE rate.

The research team said Care Quality Commission (CQC) ratings were a strong predictor of locum FTE, with practices rated as having inadequate and good services having higher locum FTE than practices that were rated as having outstanding services. Single-handed practices had substantially higher locum FTE compared with group practices, while rural practices had a 25% higher locum FTE than those in urban areas.

The team also established that practices with a higher proportion of female population had 3.3% lower locum FTE than practices that had a higher proportion of male population. A larger patient population in the 65 years and over age group was associated with 3% lower locum FTE.

They write: “The accurate monitoring of the GP workforce may help policymakers and commissioners to understand current challenges in primary care, including capacity and composition of the GP workforce and inform workforce planning. This can be particularly useful to meet local healthcare needs with sufficient resources for training and deployment of GPs, which will help ensure that the targets set out in the NHS Long Term Plan are met.

“For example, this research highlights elevated locum GP employment in practices in rural areas and those with inadequate CQC inspection ratings. These types of practices may face substantial challenges in recruiting and retaining permanent GPs, and it may be hypothesised that relatively high and sustained levels of locum use may be indicators of wider problems affecting recruitment and retention. Furthermore, the present study lays the foundation for future analysis of other existing routine primary care datasets that contain information on service utilisation and patient outcomes.”