Farmers | Controls | |
Subjects n | 145 | 144 |
Time between surveys yrs | 11.9±0.2 | 11.7±0.2 |
ΔVC mL·yr−1 | -20.61±37.7 | -26.97±43.7 |
ΔFEV1 mL·yr−1 | -13.2±32.8 | -17.0±31.5 |
ΔFEV1/VC %·yr−1 | 0.08±0.57 | 0.00±0.57 |
ΔFEF25–75% mL·yr−1 | -19.5±58.3 | -23.1±67.4 |
Data are presented as mean±sd, unless otherwise stated. Δ: change; VC: vital capacity; FEV1: forced expiratory volume in one second; FEF25–75%: mean forced expiratory flow between 25 and 75% of forced VC. Δ = (1998 value–1986 value)/(number of yrs between T1 and T3 examinations).