Table 2.

Frequency distributions of first diagnostic test and first pulmonologist visit in 5 years before diagnosis of idiopathic pulmonary fibrosis among newly diagnosed Medicare beneficiaries (N = 7,306)

	Year before Diagnosis when First Test Occurred
	Fifth Year		Fourth Year		Third Year		Second Year		First Year*
	No.	%	No.	%	No.	%	No.	%	No.	%	Cumulative %
Any diagnostic test	4,217	57.7	1,365	18.7	695	9.5	460	6.3	569	7.8	100.0
Pulmonary function testing	1,219	16.7	867	11.9	696	9.5	752	10.3	1,942	26.6	75.0
Chest radiograph	3,542	48.5	1,531	21.0	823	11.3	571	7.8	782	10.7	99.2
CT scan of the chest	1,399	19.1	978	13.4	864	11.8	962	13.2	3,103	42.5	100.0
Fiberoptic bronchoscopy	115	1.6	100	1.4	116	1.6	168	2.3	770	10.5	17.4
Autoimmune serologies	484	6.6	420	5.7	414	5.7	479	6.6	1,157	15.8	40.4
6-minute-walk test	142	1.9	127	1.7	156	2.1	229	3.1	742	10.2	19.1
Cardiopulmonary exercise testing†		N/A		N/A		N/A		N/A	33	0.5	1.1
Precipitin panel	22	0.3	26	0.4	26	0.4	47	0.6	244	3.3	5.0
Arterial blood gas	186	2.5	156	2.1	181	2.5	214	2.9	525	7.2	17.3
Oxygen saturation	753	10.3	600	8.2	566	7.7	618	8.5	1,176	16.1	50.8
Surgical lung biopsy	60	0.8	73	1.0	65	0.9	104	1.4	474	6.5	10.6
Pulmonologist visit	1,245	17.0	543	7.4	520	7.1	625	8.6	2,221	30.4	70.5

Definition of abbreviations: CT = computed tomography; N/A = not applicable.

^*Including index date (the date of diagnosis of idiopathic pulmonary fibrosis).

^†Four cell counts suppressed because of three cell sizes with counts less than 11.