Table 3.

Summary of interactions

	Multiplicative model
	Measure of interaction		Additive model
	Measure of interaction δ	P-value	Measure of interaction δ	P-value
Known interaction
Simvastatin-ciclosporin and MYP	1.48	0.089	0.014	0.0002
Methotrexate-diclofenac and BMD	1.79	0.015	0.009	0.001
Ketoconazole-terfenadine and TdP	1.71	0.27	0.011	0.038
Cisapride-erythromycin and TdP	0.32	0.0001	0.013	0.014
No known interaction
Methotrexate-rofecoxib and BMD	0.34	0.14	−0.004	0.0001
Fluvastatin-ciclosporin and MYP	0.26	0.19	−0.002	0.83
Cisapride-azithromycin and TdP	0.11	0.002	−0.0047	0.01
Fexofenadine-ketoconazole and TdP	0	*	−0.002	0.0001

^*P value not estimated as one cell contains 0. BMD bone marrow depression; MYP myopathy; TdP Torsades de Pointes.