Table 2.

Difference in FEV₁ response to albuterol and ipratropium between Day 1 and Day 10, stratified by specific thresholds

Difference between Day 1 and Day 10 (mL)	Albuterol, n=53*	Ipratropium, n=54*
<100	31	28
≥100 to <150	12	8
≥150 to <200	4	9
≥200	6	9

Notes:

^*One patient completed the ipratropium study period but not the albuterol study period; therefore, n=53 for albuterol and n=54 for ipratropium.

Abbreviation: FEV₁, forced expiratory volume in 1 second.