Data analysis
Data were entered into Statistical Package for Social Science version 22.0 (SPSS 22.0) for Windows (SPSS, Chicago, IL, USA). Both descriptive and analytical analysis were performed on the data. Due to low clinical importance of interactions with severity ratings of A, B, and C, only interactions with D (major) and X (contraindicated) scales were considered for further analysis. The interacting drugs, documentation rate, mechanism of interaction, and clinical recommendations for prevention were recorded. Descriptive analyses of the variables were expressed as mean, standard deviation [SD], median, interquartile range [IQR], and percentage as appropriate.
The association between occurrence of pDDIs and probable risk factors were assessed using logistic regression analysis. Dependent variable was defined as exposure to at least one major or contraindicated pDDI. Patient’s sex, common comorbidities (hypertension, obesity, diabetes, Ischemic Heart Disease (IHD), Chronic Respiratory Diseases (CRDs), neoplasms), and ICU admission were taken as the covariates. At the first, univariate logistic regression analysis was carried out. Variables with a significant univariate p-value (<0.05) were further assessed by multivariate analysis.