Table 4.

Concordance of Report recommendations with Fleischner Society guidelines in 2014 cases and 2017 validation set cases (as determined by manual review).

Comparison between 2014 and 2017 reports
	2014		2017
	n/total	Percentage (95% CI)	n/total	percentage	p value
Reports with ILN	108/500	21.6% (18.0 – 25.2%)	101/450	22.4% (18.7 – 26.4%)	0.754
Reports with ILN and follow-up recommendation	75/108	69.4% (60.2 – 77.8%)	80/101	79.2% (71.3 – 87.1%)	0.107
Reports with ILN and follow-up recommendation using a macro*	18/75	24.0% (14.7 – 33.3%)	38/80	47.5% (36.3 – 58.8%)	0.002
Reports with ILN and guideline concordant follow up recommendation	53/75	70.7% (60.0 – 80.0%)	60/80	75.0% (65.0 – 83.8%)	0.544
ILN Warranting Both Low and High Risk Fleischner Society Recommendations
ILN in category warranting both low and high clinical risk recommendations (if/then statement)	39/75	52.0% (41.3 – 62.7%)	39/80	48.8% (37.5 – 60.0%)	0.686
Report reflected guideline concordant recommendation	18/39	46.2% (30.8 – 61.5%)	24/39	61.5% (46.2 – 76.9%)	0.173
ILN with Imaging Features Associated with Elevated Risk for Malignancy#
ILN with imaging features suggestive of elevated risk	45/75	60.0% (49.3 – 70.7%)	39/80	48.8% (37.5 – 60.0%)	0.160
Report reflected guideline concordant recommendation	37/45	82.2% (71.1 – 93.3%)	30/39	76.9% (64.1 – 89.7%)	0.547
ILN without Imaging Features Associated with Elevated Risk for Malignancy
ILN without imaging features suggestive of elevated risk	30/75	40.0% (29.3 – 50.7%)	41/80	51.3% (40.0 – 62.5%)	0.160
Report reflected guideline concordant recommendation	16/30	55.1% (36.7 – 70.0%)	30/41	73.2% (58.5 – 85.4%)	0.084

ILN = Incidental lung nodules

^*In 2014, individual radiologists may have used personal macros while in 2017 a department-wide standardized macro was implemented.

^#elevated risk features according to American College of Chest Physicians, Fleischner Society.