Table 5.

Prescription-level multivariable models of risks associated with prescribing or monitoring errors: unadjusted and adjusted for patient clustering

Factor	Multivariable unadjusted model (model 5)a			Multivariable adjusted model (model 6)b
	Odds ratio	95% CI	P-value	Odds ratio	95% CI	P-value
Medication on monitoring list	3.18	2.05 to 4.94	<0.001	3.63	2.65 to 4.98	<0.001
Repeat prescriptionc	1.25	0.91 to 1.72	0.168	0.98	0.73 to 1.31	0.903
Formulationd
Eye/ear drops	1.43	0.39 to 5.23	0.586
Inhalers	0.51	0.21 to 1.27	0.149
Injections	0.41	0.06 to 3.07	0.387
Liquid oral	1.08	0.60 to 1.95	0.794
Rectal	1.93	0.24 to 15.42	0.535
Topical	0.66	0.31 to 1.42	0.287
Prescriber typee
Salaried GP	0.71	0.46 to 1.11	0.13	0.76	0.47 to 1.22	0.258
Locum GP	1.16	0.60 to 2.28	0.655	1.23	0.60 to 2.54	0.576
Training GP	1.42	0.67 to 3.01	0.353	1.66	0.74 to 3.72	0.218
Non-medical prescriber	1.55	0.47 to 5.13	0.469	1.09	0.30 to 3.91	0.898
Other/unknown	1.78	0.52 to 6.14	0.358	1.97	0.54 to 7.23	0.305
British National Formulary chapterf
Cardiovascular system	2.37	1.03 to 5.45	0.042
Respiratory system	2.26	0.83 to 6.17	0.11
CNS	2.09	0.95 to 4.63	0.068
Infections	2.67	1.17 to 6.11	0.02
Endocrine	1.91	0.78 to 4.72	0.159
Obstetrics, gynaecology, urinary tract disorders	1.41	0.41 to 4.80	0.584
Malignant disease and immunosuppression	6.77	1.71 to 2 6.84	0.006
Nutrition and blood	1.22	0.36 to 4.15	0.752
Musculoskeletal	6.97	3.06 to 15.88	<0.001
Eye	4.92	1.12 to 21.62	0.035
Ear nose and oropharynx	4.60	1.29 to 16.42	0.019
Skin	5.78	2.04 to 16.36	0.001
Immunology and vaccines	5.91	0.60 to 58.00	0.127
Computer systemg
EMIS PCS	1.06	0.79 to 1.42	0.706	1.13	0.80 to 1.60	0.501
Isoft Premiere	0.68	0.46 to 1.01	0.055	0.64	0.40 to 1.01	0.058
TPP	1.05	0.71 to 1.56	0.803	0.94	0.58 to 1.52	0.81

CNS = central nervous system.

^aModel unadjusted for clustering by patient.

^bModel adjusted for clustering by patient but formulation and chapter not included in the model due to non-convergence of model.

^cAcute prescriptions.

^dSolid oral medication (pessaries category omitted).

^eGP partner.

^fGastrointestinal (anaesthesia chapter omitted).

^gEMIS LV.