Figure 5
Proportional odds model estimates; The proportional odds model estimates of the odds of receiving lower tidal volume ventilation for each variable compared to a reference value, with median exhaled tidal volume categorized as > 10 mL per kg of predicted body weight (PBW), 8–10 mL per kg of PBW, and < 8 mL per kg of PBW. The triangles mark the estimate centers, with 95% confidence intervals indicated with the bars extending from the centers. For the categorical variables of year, gender and center, the estimates provided are odds of receiving lower tidal volume ventilation relative to 2005, females and center A, respectively. For height and weight, the estimates provided are the interquartile odd ratio, indicating the odds of receiving lower tidal volume ventilation at the 75th percentile of those variables compared to the 25th percentile. The p-value for each estimate is p < 0.0001 based on a likelihood ratio test with 11 degrees of freedom.