Table 2.

Formulas and thresholds of ROR and BCPNN.

Method	Formula	Threshold
ROR	ROR= $\frac{a/c}{b/d}$ 95%CI = e^ $(\mathit{\text{lnROR}}\pm 1.96\sqrt{1/a+1/b+1/c+1/d})$	a ≥ 3 and 95% CI (lower limit) > 1
BCPNN	IC= ${log}_2\frac{a(a+b+c+\mathrm{d})}{(a+b)(a+c)}$ $\gamma ={\gamma }_{\mathit{ij}}\frac{(N+\alpha )(N+\beta )}{(a+b+{\alpha }_i)(a+c+{\beta }_j)}$ $E\left(\mathit{IC}\right)={log}_2\frac{(a+{\gamma }_{\mathit{ij}})(N+\alpha )(N+\beta )}{(N+\gamma )(a+b+{\alpha }_i)(a+c+{\beta }_j)}$ $V\left(\mathit{IC}\right)={\left(\frac{1}{ln2}\right)}^2(\frac{N-\alpha +\gamma -{\gamma }_{\mathit{ij}}}{(\alpha +{\gamma }_{\mathit{ij}})(1+N+\gamma )}+\frac{N-a-b+\alpha -{\alpha }_i}{(a+b+{\alpha }_i)(1+N+\alpha )}+\frac{N-a-c+\beta -{\beta }_j}{(a+c+{\beta }_j)(1+N+\beta )})$ $\mathit{SD}=\sqrt{V\left(\mathit{IC}\right)}$ IC025= $E\left(\mathit{IC}\right)-2\mathit{SD}$	IC025 > 0