Can the detection rate of flexible bronchoscopy for lung cancer be increased by a series of simple quality improvement measures? Bronchoscopy-associated clinical parameters were prospectively recorded between 2001 and 2007 in patients with suspected lung malignancy. The detection rate of bronchoscopy, diagnostic yield of each biopsy modality and the possible impact of different service-improvement measures were assessed. 746 bronchoscopies were performed in 704 patients. The detection rate of bronchoscopy for malignancy was 83.6%, and increased over time (67.3% detection rate in 2001 (95% CI 52.9-79.7), 89.7% detection rate in 2007 (95% CI 81.3-95.2); p<0.001). Detection rate increased for bronchoscopically visible (75.0% in 2001 to 94.5% in 2007) and non-visible tumours (41.7% in 2001 to 81.2% in 2007; p<0.001 for both analyses). Prior computed tomography availability was associated with a higher diagnostic yield that did not reach statistical significance. Logistic regression analysis identified tumour visibility, year of study, use of transbronchial needle aspiration and pathologist identity as independent predictors of a positive diagnosis. A significant increase in bronchoscopic detection rate for malignancy occurred in association with a number of simple improvement measures.