Table 3

Unadjusted and adjusted HRs (with corresponding 95% CIs and p values) for lower limb amputation given QOF indicator exposures/NDA care processes after one-to-one propensity score matching; incidence rates per 1000 person-years are also included for the matched samples

Outcome	Exposure	Incidence rate		Unadjusted analyses			Adjusted analyses*
Outcome	Exposure	Exposed	Unexposed	HR	95% CI	P value	HR	95% CI	P value
First minor or major amputation	HbA1c QOF target	1.39	2.44	0.57	0.46 to 0.69	<0.0001	0.61	0.49 to 0.74	<0.0001
	Blood pressure QOF target	1.55	1.70	0.91	0.76 to 1.10	0.3278	0.88	0.73 to 1.06	0.1891
	Cholesterol QOF target	1.39	1.96	0.71	0.55 to 0.90	0.0048	0.67	0.53 to 0.86	0.0017
	All QOF targets	1.06	1.66	0.64	0.51 to 0.81	0.0002	0.64	0.50 to 0.81	0.0002
	4–6 (vs 0–3) NDA processes	1.45	2.92	0.49	0.27 to 0.87	0.0149	0.45	0.24 to 0.83	0.0106
	7–9 (vs 0–3) NDA processes	1.77	2.27	0.78	0.55 to 1.11	0.1717	0.67	0.47 to 0.97	0.0319
	7–9 (vs 4–6) NDA processes	1.34	3.04	0.44	0.25 to 0.78	0.0049	0.38	0.20 to 0.70	0.0022
	9 (vs <9) NDA processes	1.15	2.05	0.56	0.46 to 0.67	<0.0001	0.58	0.48 to 0.71	<0.0001
First major amputation	HbA1c QOF target	0.56	0.86	0.65	0.47 to 0.91	0.0114	0.69	0.49 to 0.97	0.0302
	Blood pressure QOF target	0.55	0.65	0.84	0.62 to 1.15	0.2777	0.81	0.59 to 1.10	0.1754
	Cholesterol QOF target	0.60	0.70	0.86	0.58 to 1.27	0.4502	0.84	0.56 to 1.24	0.3739
	All QOF targets	0.45	0.60	0.76	0.52 to 1.10	0.1449	0.76	0.52 to 1.11	0.1595
	4–6 (vs 0–3) NDA processes	1.05	1.34	0.78	0.37 to 1.62	0.5046	0.92	0.42 to 2.02	0.8356
	7–9 (vs 0–3) NDA processes	0.35	0.95	0.36	0.19 to 0.69	0.0021	0.32	0.16 to 0.61	0.0006
	7–9 (vs 4–6) NDA processes	0.15	1.26	0.12	0.03 to 0.53	0.0049	0.10	0.02 to 0.49	0.0042
	9 (vs <9) NDA processes	0.43	0.80	0.52	0.38 to 0.71	<0.0001	0.54	0.39 to 0.74	0.0001

*Adjusted for age, sex, ethnicity, IMD, practice region, BMI, smoking status, alcohol consumption, number of other comorbid conditions, hospitalizations, duration of diabetes, diabetes complications, number of glucose lowering therapies, and insulin prescription status.
BMI, body mass index; HbA1c, glycated hemoglobin; IMD, Index of Multiple Deprivation; NDA, National Diabetes Audit; QOF, Quality and Outcomes Framework.