Need for mechanical ventilation. Pooling the four cited studies (39) (40) (41) (42), an RR of 0.62 (95% CI 0.49 to 0.79) was obtained, with negligible heterogeneity (I2=0%), shown in Figure 8 (Forest plot of comparison: Paraffin oil versus standard therapy, outcome 1.3 Need for mechanical ventilation). In addition, the estimates were maintained with adjustments for other summary measures (OR= 0.30, 95% CI of 0.17 to 0.53). Continuing with the sensitivity analysis, the robustness of the estimates is shown by obtaining an RR of 0.68 (95% CI of 0.51 to 0.91) excluding the trials classified as having a high risk of bias (40) (41), shown in Figure 9 (Forest plot of comparison: Sensitivity analysis, outcome 1.3 Need for mechanical ventilation).