Table 4

Multiple regression using backward stepwise method

VariableCoefficent bStandard errorp Value
Adjusted R2=0.21. The full model included the following variables: age, days unwell, oxygen saturation (Sao2), C reactive protein (CRP), total white blood cell count (WBC), drain type, drug, pleural fluid characteristics, and ultrasound appearances. For the categorical variables drug, drain type, appearance of pleural fluid and ultrasound appearance, two categories were identified as described in the text and coded 0 and 1 for the purposes of the model.
Days unwell–0.0260.010.037