CRP and coronary artery disorder: If there is no intercept term in this regression, the slope parameter is the inverse-variance weighted causal estimate.48 If there is an intercept term (as in Egger regression), then under the InSIDE assumption (see later), the intercept is the average pleiotropic effect of a genetic variant; if the intercept differs from zero, then there is evidence of directional pleiotropy.46 In the example of CRP on CAD risk for the genome-wide significant variants, the P value for the test of directional pleiotropy is 0.61, indicating no evidence of directional pleiotropy.