Fig. 4.

Risk factors associated with OIRD in the multivariate regression model (using backward elimination). A backward elimination (or backward deletion) process was used in the regression model, where all predictor variables were entered into the equation first and the variable that contributes the least to the regression model was eliminated if they were above the specified stay criterion of p = 0.1. Concomitant sedatives included in the model were gabapentinoids (gabapentin, pregabalin) and benzodiazepines (alprazolam, clonazepam, diazepam, lorazepam, midazolam, midazolam hydrochloride, temazepam, zolpidem, and zolpidem tartrate)