Table 2.

Associations between regularity of GP appointments and emergency inpatient admissions and A&E attendances for the cohort: multilevel random intercept negative binomial regression models for all years 2000–2015 (inpatient admissions) and 2008–2015 (A&E attendances)^a

	Emergency inpatient admission				A&E visit

	Incidence rate ratio	95% CI		P-value	Incidence rate ratio	95% CI		P-value
Coefficient of variation for gaps between consultations
<0.75	1 (ref)				1 (ref)
≥0.75, <0.95	1.05	1.01	1.09	0.01	1.01	0.97	1.05	0.63
≥0.95, <1.20	1.07	1.03	1.12	<0.01	1.04	0.99	1.08	0.10
≥1.20	1.15	1.10	1.20	<0.01	1.05	1.01	1.10	0.03
Undefined (<2 consultation gaps in year)	1.24	1.19	1.29	<0.01	0.91	0.88	0.95	<0.01

No. of consultations in year	1.04	1.04	1.04	<0.01	1.03	1.03	1.03	<0.01
Year	0.96	0.95	0.96	<0.01	1.03	1.03	1.04	<0.01

Sex
Male	1 (ref)				1 (ref)
Female	1.04	1.00	1.08	0.08	0.95	0.91	0.99	0.02

Ethnic group
Black African	1.11	0.95	1.30	0.17	1.06	0.92	1.22	0.43
Black Caribbean	1.31	1.04	1.64	0.02	1.49	1.19	1.88	<0.01
Black other	1.39	1.09	1.79	0.01	1.50	1.19	1.89	<0.01
Bangladeshi	1.16	0.84	1.61	0.37	0.92	0.68	1.24	0.58
Chinese	0.83	0.56	1.23	0.35	1.06	0.72	1.55	0.78
Indian	0.86	0.73	1.01	0.07	0.93	0.79	1.08	0.34
Pakistani	1.07	0.94	1.22	0.30	0.99	0.87	1.13	0.89
Other Asian	1.36	1.14	1.61	<0.01	1.24	1.06	1.46	0.01
White	1 (ref)				1 (ref)
Mixed	1.24	1.08	1.42	<0.01	1.16	1.02	1.32	0.02
Other	1.08	0.92	1.27	0.33	1.19	1.03	1.38	0.02

Age group, years
<1	3.48	3.29	3.68	<0.01	1.94	1.79	2.11	<0.01
1–5	1 (ref)				1 (ref)
6–10	0.46	0.45	0.48	<0.01	0.65	0.62	0.68	<0.01
11–15	0.44	0.42	0.46	<0.01	0.69	0.65	0.73	<0.01
16–20	0.44	0.41	0.46	<0.01	0.72	0.68	0.76	<0.01
21–25	0.43	0.41	0.46	<0.01	0.80	0.75	0.84	<0.01

Main diagnostic group
Circulatory	1.79	1.56	2.06	<0.01	1.22	1.06	1.39	0.01
Congenital	1 (ref)				1 (ref)
Gastrointestinal	2.80	2.36	3.32	<0.01	1.32	1.12	1.56	<0.01
Genitourinary	3.05	2.78	3.36	<0.01	1.65	1.51	1.82	<0.01
Haematology	1.84	1.67	2.03	<0.01	1.19	1.08	1.31	<0.01
Metabolic	1.97	1.78	2.19	<0.01	1.34	1.20	1.49	<0.01
Neurology	1.70	1.60	1.81	<0.01	1.33	1.25	1.41	<0.01
Oncology	1.93	1.82	2.06	<0.01	1.01	0.95	1.08	0.68
Perinatal	0.89	0.76	1.05	0.17	0.97	0.83	1.12	0.65
Respiratory	2.29	2.12	2.47	<0.01	1.29	1.19	1.39	<0.01
Other	1.53	1.23	1.90	<0.01	1.23	1.01	1.50	0.04

Deprivation category
1 (least deprived)	0.72	0.67	0.77	<0.01	0.63	0.59	0.67	<0.01
2	0.75	0.70	0.80	<0.01	0.66	0.62	0.71	<0.01
3	0.82	0.77	0.88	<0.01	0.78	0.73	0.83	<0.01
4	0.95	0.89	1.01	0.10	0.86	0.80	0.91	<0.01
5 (most deprived)	1 (ref)				1 (ref)

Model parameters
Degrees of freedom	39				39
Log likelihood	−91 244.5				−63 549.9
BIC	182 939.0				127 531.9

↵a ’No. of consultations in year’ and ‘Year’ are continuous variables — incident rate ratios indicate the expected proportional change in outcome rate for one additional consultation and 1 year later in time. A&E = accident and emergency. BIC = Bayesian information criterion.