Table 4.

 Final GEE model of the average hearing threshold (in units of dB HL) among full cohort of all farmers for the low and high-frequency bands (n = 670 ears)

Variables	Low frequency (0.5–2 kHz)			High frequency (3–6 kHz)
	β	SE	P-value	β	SE	P-value
Model 1: years of exposure
Intercept	11.310	2.082	<0.001*	1.075	3.502	0.759
Years using pesticides	0.047	0.050	0.355	0.223	0.078	0.004*
Years using agricultural machinery	−0.115	0.046	0.062	0.231	0.089	0.009*
Ear
Right	0.00	—	—	0.00	—	—
Left	2.488	0.443	<0.001*	1.876	0.570	0.001*
Age (years)	0.259	0.049	<0.001*	0.444	0.084	<0.001*
Industrial noise ever
Never	0.00	—	—	0.00	—	—
Ever	0.311	1.032	0.763	3.535	1.904	0.063
Cigarette smoking
Never	0.00	—	—	0.00	—	—
Former	−0.396	1.031	0.701	4.419	1.960	0.024*
Current	3.535	2.854	0.216	9.244	3.994	0.021*

*Significant at P-value 0.05.