Clinical parameters of patients. Patients that developed pneumonia had comparable age, weight and duration of operation to controls that had no postoperative pneumonia. (A): Patients demographic data in a table format. (B-C): The patients who developed postoperative pneumonia were matched according to sex, age, weight and length of brain surgery. Data were compared using the non-parametric Mann-Whitney test and expressed as "box and whiskers: 10–90 percentile".