Table 2.

Odds of continuing treatment beyond 30, 90, and 180 days by patient and practice level variables. Full model with overlapping patient and practice variables

	Continuation beyond 30 days			Continuation beyond 90 days			Continuation beyond 180 days

	OR	95% CI	P-value	OR	95% CI	P-value	OR	95% CI	P-value
Patient variables
Male	1.00	0.94 to 1.06	0.95	0.92	0.87 to 0.98	0.01	0.92	0.86 to 1.00	0.04
Deprivation^a	0.98	0.95 to 1.01	0.18	0.96	0.93 to 0.99	0.007	0.97	0.93 to 1.00	0.07
Age 35–64 years	1.25	1.18 to 1.34	<0.001	1.40	1.32 to 1.50	<0.001	1.53	1.41 to 1.66	<0.001
Age ≥65 years	1.13	1.04 to 1.23	0.006	1.39	1.27 to 1.52	<0.001	1.83	1.64 to 2.05	<0.001
Episode coded^b	1.99	1.85 to 2.14	<0.001	1.70	1.59 to 1.83	<0.001	1.56	1.44 to 1.70	<0.001

Practice variables
Female GPs^c	1.23	1.00 to 1.50	0.04	1.19	0.98 to 1.45	0.09	1.34	1.06 to 1.68	0.01
Deprivation^d	0.97	0.93 to 1.01	0.11	0.98	0.94 to 1.02	0.31	1.00	0.95 to 1.04	0.90
Practice list size^e	1.00	0.99 to 1.02	0.67	1.00	0.99 to 1.01	0.99	1.00	1.00 to 1.00	0.63
Episodes coded^f	0.81	0.63 to 1.03	0.08	0.81	0.64 to 1.02	0.08	0.90	0.69 to 1.18	0.46
Prescribing rate^g	1.00	0.99 to 1.00	0.22	1.00	0.99 to 1.01	0.64	0.99	0.98 to 1.00	0.14

Model fit described using Akaike Information Criterion. Values for 30 days = 28 043; 90 days = 26 170, and 180 days = 17 618.
↵a Per category of the 7 category DepCat measure.
↵b Entry during the treatment period of a Read Code for a depression or anxiety disorder.
↵c Proportion of GPs in the practice who were female not adjusted for part-time working.
↵d Per DepCat category of the practice main address.
↵e List size in thousands.
↵f Proportion of cases with one or more Read Codes indicative of depression or anxiety during the treatment period.
↵g Patients prescribed new antidepressant treatment per thousand registered patients.