Table 1.

Statistical analysis

		Central		Peripheral		Total
		Count	Percent	Count	Percent	Count	Percent
No. of patients		25	44.6	31	55.4	56
Age	Range	52–88		52–82		52–88
	Mean	67		70		69
Sex	Male	19	76.0	19	61.3	38	67.9
	Female	6	24.0	12	38.7	18	32.1
Race	Caucasian	23	92.0	24	77.4	47	83.9
	African American	2	8.0	5	16.1	7	12.5
	Other	1		1	3.2	2	3.6
Smoking status	Current	8	32.0	12	38.7	20	35.7
	Past (quit >6 months)	16	64.0	19	61.3	35	62.5
	Never	1	4.0	0	0.0	1	1.8
PPI use		7	28.0	6	19.4	13	23.2
Inhaler use		14	56.0	18	58.1	32	57.1
Right lung	Total	13	52.0	16	51.6	29	51.8
	Upper	5	38.5	9	56.2
	Middle	8	61.5	0	0.0
	Lower	0	0.0	7	43.8
Left lung	Total	11	44.0	14	45.2	25	44.6
	Upper	4	36.4	11	78.6
	Lower	7	63.6	3	21.4

Data were managed with Microsoft Excel 2010. Student's t-test was used to compare the means for the ages of the two study groups, and a chi-square test was used to compare the rest of the demographic features and risk factors mentioned above. A p-value of <0.05 was used for all the analyzed data.