Primary care mortality and the impact of funding: a national longitudinal study 2013 -2016
Problem
Previous studies reporting an association between primary care investment and practice-level mortality have relied on estimates of mortality or been confined to small geographical areas. We investigated the relationship between funding and actual mortality rates, both at practice-level, in a national sample of practices in England.
Approach
We combined seven datasets for all general practices in England (n=7310), 2013-2016: (i) General and Personal Medical Services database , providing workforce and patient data; (ii) NHS payments to General Practice, which records payments to practices; (iii) Quality and Outcomes Framework describing performance on clinical achievement indicators in LTCs, (iv) deprivation data for each practice; (v) neighbourhood ethnicity for each practice; (vi) patient experience scores from the General Practice Patient Survey; and (vii)practice-level mortality. We estimated a variety of count data models using longitudinal practice-level data to examine the association between general practice funding and practice-level mortality. These included (a)pooled models; (b) practice fixed effect models; (c) random effects models; and (d) Mundlak specification. We used the Poisson specification for models with practice fixed effects and allowed for over-dispersion of errors by using robust standard errors. Practice-year observations with <5 deaths/year were truncated. We entered the number of general practitioners, nurses and administrative staff in four different ways in the exponential mean function. The goodness of fit for each model was explored using the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC), both of which penalise the number of coefficients estimated; smaller AIC and BIC scores indicate better fitting models.
Findings
The inflation adjusted mean total funding per patient across the study period was £133.66 (standard deviation £39.46), adjusted to 2016 costs. The mean total deaths per practice increased from 61.23 (SD 46.15) in 2013/14 to 65.78 (SD 50.52) in 2016/17. Premature mortality (deaths in those <75 years) also increased from 19.22(SD 13.09) in 2013/14 to 20.86 (SD14.45) in 2016/17. Reduced practice mortality rates were significantly associated with increased total funding (B coefficient -0.003; %95CI: -0.0004, -0.0001). Other characteristics associated with reduced mortality included: practices in receipt of the capitation supplement, (MPIG) (B coefficient -0.02; %95CI: -0.04, -0.01); practices with less deprived populations (B coefficient 0.011; %95CI: 0.010, 0.011); and practices with increased overall patient experience scores (B coefficient -0.001; %95CI: -0.001, -0.0001). The relationship between mortality and patient age was U-shaped, with extremes of age 0- 4 years (B coefficient 0.03; %95CI: 0.03, 0.04) and ≥75 years (B coefficient 0.10; %95CI:0.10, 0.11) significantly associated with practice mortality.
Consequences
This is the first study to examine general practice funding and practice-level mortality rates in England. We found that practice mortality rates are inversely related to the underlying funding allocated to each general practice. Further work is needed to determine the likely mechanism of any causal relationship between funding and mortality.