Table 2.

Results for the established drug–drug interaction

Algorithm	Variable	n	Value
Ω shrinkage measure	Ω025	5	1.23
Logistic regression	OR (interferon alfa-2a)	1	13.16 (1.65–91.95)
	OR (ribavirin)	0	0 (0–∞)
	OR (drug combination)	5	129.68 (45.45–334.85)
The additive model	δ	5	0.07
The multiplicative model	δ	5	*

n, the number of the combinations when both of the drugs were used concomitantly and a certain adverse drug reaction was caused as a result. The P-value for the interaction term of AB in the logistic model was <0.001. The P-value for the additive and multiplicative model was 0.021 and <0.001, respectively.

^*RRA × RRB was 0 and the δ could not be calculated as a result.