Some additional tips on how to differentiate a pleural effusion/haemothorax from other pulmonary pathology or overlying soft tissue have been added to the Pleural effusion page in the Respiratory section. Additional links between the Thoracic trauma page (containing haemothorax and pneumothorax) in the Trauma section and the Pleural effusion and Penumothorax pages in the Respiratory section have been added due to the significant overlap of content.