Table 3.

Change in mean absolute risk at 12 month follow up by baseline risk and trial arm

Baseline risk category (%)	Mean absolute risk
	Computer support plus chart	Chart only	Usual care
<10	3.8	2.3	0.9
10-19.9	1.5	0.7	1.8
⩾20	−1.7	−1.7	−0.3
All	0.7	−0.5	0.8

Test for interaction between trial arm and baseline risk (using baseline risk as a continuous variable): F(2, 524)=4.88, P<0.01.