An Intervention to Tag Findings Suspicious for Lung Cancer on Chest Computed Tomography Has Good Sensitivity and Number Needed to Diagnose.

BACKGROUND: In 2015, Kaiser Permanente Northern California implemented an intervention to improve follow-up for pulmonary findings on diagnostic chest computed tomography (CT). The intervention includes tagging CT reports with the prefix "#PUL" followed by a character (0-6 or X) to track specific findings. #PUL5, indicating "suspicious for malignancy," triggers automatic referral for multidisciplinary care review.
METHODS: Among patients who obtained an index chest CT exam from August 2015 to July 2017 without an exam in the previous 2 years, we computed the frequency of lung cancer diagnosis within 120 days of CT in relation to each #PUL tag. For #PUL5, we computed sensitivity, specificity, positive and negative predictive values, and number needed to diagnose. We also performed a chart review to assess why some patients diagnosed with lung cancer were not tagged #PUL5.
RESULTS: Of the 39,409 patients with a tagged CT report, 1105 (2.8%) had a new primary lung cancer diagnosis within 120 days. Among the 2255 patients tagged #PUL5, 821 were diagnosed with lung cancer, with a sensitivity of 74% (95% confidence interval, 72%-77%). The positive predictive value was 36% (35%-38%), number needed to diagnosis was 2.7 (2.6-2.9), and specificity and negative predictive values were > 95%. Chart review identified opportunities to improve system defaults and clarify concepts.
CONCLUSION: The intervention performed well but needed improvement. Automating CT reports was simple and generalizable, and enabled reduction of care gaps and system improvement.