Type | Effect size | Point estimate | Sampling variance estimate | Reference |
---|---|---|---|---|
Single group | Mean | \(\overline{x}_{i}\) | \({s}_{i}^{2}/{n}_{i}\) | [134] |
Single group | Proportion | \({p}_{i}=\frac{{y}_{i}}{{n}_{i}}\) | \(\frac{{p}_{i}\left(1-{p}_{i}\right)}{{n}_{i}}=\frac{{y}_{i}\left({n}_{i}-{y}_{i}\right)}{{n}_{i}^{3}}\) | [134] |
Single group | Log standard deviation (lnSD) | \({\text{ln}}{s}_{i}\) | \(\frac{1}{2\left({n}_{i}-1\right)}\) | [27] |
Single group | Log coefficient of variation (lnCV) | \(\ln \left( {\frac{{S_{i} }}{{\overline{x}_{i} }}} \right)\) | \(\frac{{s_{i}^{2} }}{{n_{i} \overline{x}_{i}^{2} }} + \frac{1}{{2\left( {n_{i} - 1} \right)}}\) | [27] |
Comparative | Mean difference (MD) | \(\overline{x}_{iT} - \overline{x}_{iC}\) | \(\frac{{s}_{iC}^{2}}{{n}_{iC}}+\frac{{s}_{iT}^{2}}{{n}_{iT}}\) | [134] |
Comparative | Standardised mean difference (SMD) | \(d_{i} = \frac{{\overline{x}_{iT} - \overline{x}_{iC} }}{{\sqrt {\frac{{\left( {n_{iC} - 1} \right)s_{iC}^{2} + \left( {n_{iT} - 1} \right)s_{iT}^{2} }}{{n_{iC} + n_{iT} - 2}}} }}\) | \(\frac{1}{{n}_{iC}}+\frac{1}{{n}_{iT}}+\frac{{d}_{i}^{2}}{2\left({n}_{iC}+{n}_{iT}\right)}\) | [25] |
Comparative | Risk (proportion) difference (RD) | \(\frac{{y}_{iT}}{{n}_{iT}}-\frac{{y}_{iC}}{{n}_{iC}}\) | \(\frac{{y}_{iT}\left({n}_{iT}-{y}_{iT}\right)}{{n}_{iT}^{3}}+\frac{{y}_{iC}\left({n}_{iC}-{y}_{iC}\right)}{{n}_{iC}^{3}}\) | [134] |
Comparative | Log odds ratio (lnOR) | \({\text{ln}}\left(\frac{{y}_{iT}}{{n}_{iT}-{y}_{iT}}\right)-{\text{ln}}\left(\frac{{y}_{iC}}{{n}_{iC}-{y}_{iC}}\right)\) | \(\frac{1}{{y}_{iT}}+\frac{1}{{n}_{iT}-{y}_{iT}}+\frac{1}{{y}_{iC}}+\frac{1}{{n}_{iC}-{y}_{iC}}\) | [134] |
Comparative | Log response ratio (lnRR) | \({\text{ln}}\left( {\frac{{\overline{x}_{iT} }}{{\overline{x}_{iC} }}} \right)\) | \(\frac{{s_{iC}^{2} }}{{n_{iC} \overline{x}_{iC}^{2} }} + \frac{{s_{iT}^{2} }}{{n_{iT} \overline{x}_{iT}^{2} }}\) | [135] |
Comparative | Log variability ratio (lnVR) | \({\text{ln}}\left(\frac{{s}_{iT}}{{s}_{iC}}\right)\) | \(\frac{1}{2\left({n}_{iC}-1\right)}+\frac{1}{2\left({n}_{iT}-1\right)}\) | [27] |
Comparative | Log coefficient of variation ratio (lnCVR) | \({\text{ln}}\left( {\frac{{s_{iT} }}{{\overline{x}_{iT} }}} \right) - {\text{ln}}\left( {\frac{{s_{iC} }}{{\overline{x}_{iC} }}} \right)\) | \(\frac{{s_{iC}^{2} }}{{n_{iC} \overline{x}_{iC}^{2} }} + \frac{1}{{2\left( {n_{iC} - 1} \right)}} + \frac{{s_{iT}^{2} }}{{n_{iT} \overline{x}_{iT}^{2} }} + \frac{1}{{2\left( {n_{iT} - 1} \right)}}\) | [27] |
Association | Fisher’s z-transformation of correlation, r (Zr) | \(\frac{1}{2}{\text{ln}}\left(\frac{1+{r}_{i}}{1-{r}_{i}}\right)\) | \(\frac{1}{{n}_{i}-3}\) | [134] |