Table 1

Response and selected characteristics of responders to stage II

  • 1-1 Responded to at least the questions on smoking.

  • 1-2 Valid slope, therefore at least two doses of methacholine.

  • 1-3 Subjects who declined lung function or were ineligible for challenge or unable to proceed.

  • 1-4 Subjects who had baseline lung function but were ineligible for challenge, declined further participation, or were unable to proceed.

  • RI = respiratory infection; FEV1 = forced expiratory volume in one second; FVC = forced vital capacity.