Odds ratios should be avoided when events are common. Altman DG (1991) Practical statistics for medical research.
A standard normal deviate ( z-value) is calculated as ln(OR)/SE, and the P-value is the area of the normal distribution that falls outside ± z (see Values of the Normal distribution table). Test of significance: the P-value is calculated according to Sheskin, 2004 (p. En su esencia, MedCalc aloja soporte para procedimientos estadsticos paramtricos y no paramtricos bsicos, herramientas para metanlisis y clculos de tamao de muestra, y una amplia gama de resultados grficos (estadstica descriptiva, regresin no lineal, regresiones logsticas, ANOVA, Mann Prueba de Whitney, prueba de. Where zeros cause problems with computation of the odds ratio or its standard error, 0.5 is added to all cells (a, b, c, d) (Pagano & Gauvreau, 2000 Deeks & Higgins, 2010). With the standard error of the log odds ratio being The odds ratio (OR), its standard error and 95% confidence interval are calculated according to Altman, 1991.