Table 6.

Univariate Analysis of the Relation of Baseline Coronary Event Rate to the Odds Ratio and Risk Difference of Stroke in Cholesterol-Lowering Trials ^*

Outcome	Measure of Association †,‡	Correlation Coefficient r	Regression Coefficient β	p Value
Fatal stroke	Odds ratio	.2495	.0088	.7338
	Risk difference	.4768	.0125	.4716
Nonfatal stroke	Odds ratio	−.5486	−.0143	.2302
	Risk difference	−.7607	−.0946	.0140
Total stroke	Odds ratio	−.3841	−.0096	.3844
	Risk Difference	−.6757	−.0848	.0366

^*Risk differences for individual trials were computed using Meta-Analyst Version 0.98. To avoid undefined variance terms, a value of 0.5 was added to each cell when any cell contained 0.

^†Regression of the odds ratios to baseline coronary event rates were performed using the natural log scale (ln OR). Risk difference was defined as the incidence rate difference for 1,000 patient-years. Baseline coronary event rates were computed as the number of coronary events on placebo treatment per 1,000 patient-years.

^‡Regression weights were computed for each trial by the inverse of the square of their standard errors.