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

Table 4 Crude and adjusted c-section RRs of hospitals in group III

Hospital	n	Crude RR	p–value	Adj* RR	p–value	% variation†
A	684	0.94	0.770	1.04	0.855	10.6
B	408	1.13	0.614	1.27	0.295	12.4
C	327	0.35	0.021	0.38	0.034	8.6
D	120	1.15	0.733	1.18	0.669	2.6
E	347	0.86	0.604	0.92	0.755	7.0
F	379	0.24	0.005	0.21	0.002	−12.5
G	393	0.76	0.342	0.89	0.671	17.1
H	120	0.96	0.924	1.14	0.771	18.8
I	460	0.90	0.671	1.00	0.999	11.1
J	616	1.60	0.007	1.68	0.001	5.0
K	586	1.57	0.012	1.70	0.002	8.3
L	1,295	0.73	0.077	0.77	0.127	5.5
M	150	5.82	<0.001	3.69	<0.001	−36.6
N	106	5.21	<0.001	5.04	<0.001	−3.3
O	717	1.70	0.001	1.72	<0.001	1.2
P	576	1.72	0.002	1.76	0.001	2.3
Q	1,325	0.31	<0.001	0.35	<0.001	12.9
R	1,282	1.42	0.015	1.45	0.009	2.1
S	103	2.68	0.001	2.96	<0.001	10.4
T	77	5.08	<0.001	3.50	<0.001	−31.1
U	1,283	2.54	<0.001	2.21	<0.001	−13.0
V	1,182	0.58	0.008	0.54	0.003	−6.9
W	1,664	1.20	0.189	1.25	0.101	4.2
X	1,926	3.40	<0.001	2.93	<0.001	−13.8
Y	491	1.17	0.466	1.12	0.579	−4.3

* Adjusted for: age, severe co-morbid illness of the mother, HIV, diabetes, hypertension, lung diseases, ante-partum haemorrhage/abruption placentae/placenta praevia, eclampsia/pre-eclampsia, foetal-pelvic disproportion/excessive development of the infant, foetal anomalies, RH-isoimmunisation, polyhydramnios, oligohydramnios, problem of the amnios, congenital malformation, intrauterine growth retardation, post-maturity and macrosomia.
† The % variation is computed as (crude RR-adj RR)*100/crude RR.

ISSN: 1471-2393