. Author manuscript; available in PMC: 2010 Mar 14.

Published in final edited form as: J Allergy Clin Immunol. 2007 Feb;119(2):405–413. doi: 10.1016/j.jaci.2006.11.639

TABLE II.

Frequency of ATS severity⁸ criteria by disease severity

	Mild (n = 164)	Moderate (n = 70)	Severe (n = 204)	P value
Major criteria
OCSs for ≥50% of year	0.6%	0%	32%	ND
High-dose ICSs	0%	0%	98%	ND
Minor criteria
Daily 2nd controller medication	52%	79%	94%	<.0001^*
Daily SABA^‡	27%	44%	75%	<.0001^*
Persistent airflow obstruction^§	0%	100%	78%	ND
≥1 urgent care visits/y	16%	31%	54%	<.0001^*
≥3 OCS bursts/y	5%	13%	54%	<.0001^†
Deterioration with reduced corticosteroids	32%	60%	78%	<.0001^*
Near-fatal event in the past	4%	6%	23%	<.0001^†

ND, Not determined.

Three-way comparison significant; all groups are different.

^†

Three-way comparison, significant because of differences between severe vs mild and moderate.

^‡

Includes subject report of SABA prophylactic before exercise.

^§

Baseline FEV₁ ≤ 80%; measurement with bronchodilator withhold; ATS definition does not require withhold of bronchodilators.