. 2015 Sep 1;192(5):551–558. doi: 10.1164/rccm.201503-0426OC

Table 2.

Baseline Demographics

Characteristic	Age <30 (n = 621)		Age ≥30 (n = 579)		P Value
Characteristic	n	Mean (95% CI)	n	Mean (95% CI)	P Value
Male^*	621	271 (43.6)	579	249 (43.0)	0.825
Nonwhite race^*	621	203 (32.7)	579	202 (34.9)	0.421
BMI, kg/m²^†	621	25.1 (24.7–25.5)	579	28.2 (27.7–28.7)	<0.001^‡
A.M. peak flow, L/min^†	621	446.3 (437.8–454.8)	578	423.3 (413.7–432.9)	<0.001^‡
P.M. peak flow, L/min^†	621	464.2 (455.7–472.7)	578	438.4 (428.8–447.9)	<0.001^‡
FEV₁, L^†	621	3.20 (3.14–3.26)	579	2.76 (2.70–2.82)	<0.001^‡
FEV₁ % predicted^†	621	85.7 (84.6–86.8)	579	80.2 (79.1–81.3)	<0.001^‡
Albuterol 2-puff reversibility^§	197	7.63 (3.97–13.42)	131	7.98 (4.11–14.75)	0.526
Maximum reversibility^§	202	10.27 (6.29–16.97)	181	10.47 (6.56–17.33)	0.629
PC₂₀, mg/ml^§	573	1.04 (0.39–3.05)	546	1.20 (0.49–3.59)	0.082
Daily symptom score, 0 = absent–3 = severe^§	620	0.20 (0.06–0.43)	578	0.20 (0.06–0.45)	0.685
Daily β-agonist rescue puffs, # of puffs^§	145	0.54 (0.08–1.69)	162	0.88 (0.11–2.14)	0.123
Exhaled nitric oxide, ppb^§	325	15.70 (10.60–24.30)	354	13.65 (8.90–22.10)	0.009^‡
Asthma quality-of-life score, 1 = worst–7 = best^§	529	5.88 (5.34–6.34)	506	5.77 (5.10–6.31)	0.072
IgE, IU/ml^§	213	164.0 (74.3–365.0)	237	141.0 (53.9–309.0)	0.160
Sputum eosinophils^§	279	0.40 (0.0–2.0)	325	0.70 (0.20–2.50)	0.056
Blood eosinophils^§	217	200.0 (120.0–330.0)	251	200.0 (110.0–300.0)	0.543
Treatment failure^*	621	64 (10.3)	579	100 (17.3)	<0.001^‡

Definition of abbreviations: BMI = body mass index; CI = confidence interval; PC₂₀ = methacholine provocative concentration required to produce a 20% decline in FEV₁.

All baseline comparisons are based on unique subjects across all studies using the most recent study data for subjects in multiple studies, with treatment failures taking precedence.

Chi-square test, frequency (percentage).

^{^†}

Two-sample t test, mean (95% CI).

^{^‡}

P < 0.05.

^{^§}

Wilcoxon rank sum test, median (quartile 1–quartile 3).