Table.

Aspirin prophylaxis in patients after myocardial infarction in 45 general practices in Leicestershire

	Phase 1* (n=1264)	Phase 2 (n=1258)†	Significance
No of patients taking aspirin	957	1058	—
No (%) of patients with contraindication to aspirin	127 (10.0)	163 (13.0)	—
% of patients treated, excluding those with contraindication (95% CI)	84.2 (81.9 to 86.2)	96.6 (95.4 to 97.6)	χ2=97.1, P<0.0001

^*All eligible patients were receiving aspirin in 12 practices. 

^†Excludes six patients who had been given incorrect diagnosis, who had died, or who had moved away.