Risk adjustment models for interhospital comparison of CS rates using Robson’s ten group classification system and other socio-demographic and clinical variables

Table 5 Crude and adjusted c-section RRs of hospitals in group IV

Hospital	n	Crude RR	p–value	Adj* RR	p–value	% variation†
A	188	1.42	0.004	1.23	0.070	−13.4
B	105	1.80	<0.001	1.58	<0.001	−12.2
C	73	1.51	0.013	1.47	0.017	−2.6
D	35	2.36	<0.001	2.50	<0.001	5.9
E	127	1.08	0.621	1.07	0.637	−0.9
F	187	0.82	0.213	0.85	0.289	3.7
G	120	1.02	0.930	1.04	0.819	2.0
H	44	1.70	0.005	1.52	0.020	−10.6
I	168	1.47	0.002	1.41	0.004	−4.1
J	242	1.30	0.025	1.16	0.178	−10.8
K	162	1.50	0.001	1.41	0.003	−6.0
L	316	0.95	0.647	0.92	0.487	−3.2
M	43	0.64	0.206	0.62	0.157	−3.1
N	91	0.26	0.001	0.27	0.001	3.8
O	143	0.58	0.010	0.57	0.009	−1.7
P	225	1.22	0.102	1.13	0.287	−7.4
Q	398	1.28	0.015	1.20	0.059	−6.3
R	410	1.76	<0.001	1.69	<0.001	−4.0
S	71	2.49	<0.001	2.30	<0.001	−7.6
T	40	2.26	<0.001	1.91	<0.001	−15.5
U	370	1.77	<0.001	1.56	<0.001	−11.9
V	266	0.96	0.755	0.87	0.250	−9.4
W	671	1.17	0.102	1.18	0.074	0.9
X	527	0.47	<0.001	0.48	<0.001	2.1
Y	151	1.17	0.274	1.04	0.777	−11.1

* Adjusted for: age, severe co-morbid illness of the mother, lung diseases, ante-partum haemorrhage/abruption placentae/placenta praevia, eclampsia/pre-eclampsia, foetal-pelvic disproportion/excessive development of the infant, oligohydramnios, premature rupture of the membranes, abortion threats/assisted fecundation, congenital malformation, post-maturity and macrosomia.
† The % variation is computed as (crude RR-adj RR)*100/crude RR.

ISSN: 1471-2393