Skip to main content
. 2013 Apr 29;63(610):e339–e344. doi: 10.3399/bjgp13X667204

Table 3.

Model 2: predictors of percentages of patients reporting being able to get an appointment quickly at their practice, n = 8079 in final modela

Predictor Beta (95% CI) IRRb (95% CI) Effect size P-value
Number of patients on practice hypertension register −0.0002 (−0.0002 to −0.0001) 0.9999 (0.9998 to 0.9999 ) −0.01% <0.001
GPs per 1000 practice population 0.28 (0.25 to 0.32) 1.33 (1.28 to 1.38 ) 33% <0.001
Proportion aged ≥65 years 0.007 (0.005 to 0.009) 1.01 (1.005 to 1.009) 1% <0.001
IMD −0.0007 (−0.002 to −0.0001) 0.9994 (0.998 to 0.9999) −0.06% 0.013
Practice list size −0.0001 (−0.0001 to −0.0001) 0.99987 (0.99987 to 0.99988) −0.013% <0.001
Total Quality and Outcomes Framework points for hypertension management −0.002 (−0.004 to −0.001) 0.998 0.996 − 0.999 −0.2% <0.001

IMD = Index of Multiple Deprivation. IRR = incident rate ratio.

a

Statistical model: negative binomial regression, using log of the list size as the offset.

b

Subtracting 1 from the IRR and then multiplying by 100 gives the percentage change in the expected count for a one-unit increase in the predictor. So for GPs per 1000 practice population, for every extra GP per 1000, the expected percentage of patients able to get an appointment fairly quickly increases by 33%. IRR values less than 1.0 represent decreases and IRR values greater than 1.0 represent increases in the count.