Comparisons of hearing threshold changes in male workers with unilateral conductive hearing loss exposed to workplace noise: a retrospective cohort study for 8 years

Table 4 Comparisons of threshold changes between SNHL and CHL ear during follow-up period by age

	Age < 50 years (N = 42)									Age ≥ 50 years (N = 36)
	Difference of Air conduction			Difference of Bone conduction			Difference of Air-bone gap			Difference of Air conduction			Difference of Bone conduction			Difference of Air-bone gap
kHz	Mean^a	SD^d	p	Mean^b	SD^d	p	Mean^c	SD^d	p	Mean^a	SD^d	p	Mean^b	SD^d	p	Mean^c	SD^d	p
0.5	−2.0	8.7	0.136	−1.9	8.6	0.158	−0.1	5.9	0.875	0.7	6.8	0.544	−0.3	19.4	0.925	1.0	20.4	0.771
1	−3.7	9.5	0.017	−4.0	9.6	0.011	0.3	5.3	0.729	2.1	9.4	0.180	−0.9	9.9	0.582	3.1	8.7	0.042
2	−2.5	9.8	0.110	−2.3	9.1	0.113	−0.2	6.7	0.837	1.7	8.9	0.268	0.7	11.2	0.724	1.0	7.1	0.404
3	1.4	11.2	0.420	1.9	9.7	0.220	−0.5	8.6	0.735	1.8	8.2	0.208	1.0	8.7	0.481	0.7	6.6	0.518
4	2.5	10.8	0.134	1.3	7.3	0.271	1.3	7.7	0.283	4.1	9.5	0.015	0.4	7.0	0.740	3.7	7.3	0.005
6	0.5	15.0	0.838	-	-	-	-	-	-	1.0	10.8	0.593	-	-	-	-	-	-

p-value was calculated by paired t-test; ^aMean, difference of air conduction threshold (2013-2006) at SNHL ear vs. difference of air conduction threshold (2013-2006) at CHL ear; ^bMean, difference of bone conduction threshold (2013-2006) at SNHL ear vs. difference of bone conduction threshold (2013-2006) at CHL ear; ^cMean, average of air-bone gap; ^dSD, standard deviation

ISSN: 2052-4374