Persistent mental and physical health impact of exposure to the September 11, 2001 World Trade Center terrorist attacks

Table 5 Comparison of participants and non-participants in Wave 4

	Participants		Non-Participants
Characteristic	N	%	N	%	p-value
Overall	36,864	54.6	30,640	45.4
Sex
Male	22,291	60.5	18,280	59.7	.03
Female	14,573	39.5	12,360	40.3
Age on 9/11
<18	886	2.4	1461	4.8	<.01
18–24	1776	4.8	2561	8.4
25–44	18,840	51.1	17,527	57.4
45–64	14,453	39.2	8082	26.5
65+	891	2.4	912	3.0
Race/ethnicity
White	25,682	69.7	16,896	55.1	<.01
Black or African American	3554	9.6	4539	14.8
Hispanic or Latino	4204	11.4	4922	16.1
Asian	2134	5.8	2739	8.9
Other	1290	3.5	1544	5.0
Education
Less than high school	8200	22.4	9191	30.7	<.01
At least some college	8999	24.6	7148	23.9
College or higher	19,384	53.0	13,617	45.5
Income
Less than $25,000	2932	8.8	3938	14.8	<.01
$25,000 - $74,999	13,644	41.1	11,725	44.2
$75,000 - $150,000	12,483	37.6	7892	29.8
$150,000 or more	4169	12.6	2976	11.2
Smoking status
Never	21,019	57.8	17,566	59.3	<.01
Former	10,311	28.3	6774	22.9
Current	5060	13.9	5267	17.8
Self identified
Yes	27,684	75.1	19,840	64.8	<.01
No	9180	24.9	10,800	35.3
Registry eligibility group
Rescue/recovery worker	16,976	46.7	12,602	41.8	<.01
Lower Manhattan area resident	5361	14.8	6237	20.7
Area workers and school staff/students	12,600	34.7	10,000	33.2
Passersby	1417	3.9	1310	4.4
Dust cloud exposure
Yes	19,121	52.1	15,602	51.2	.02
No	17,575	47.9	14,873	48.8
Personally witnessed trauma on 9/11
Yes	25,130	69.5	20,849	69.7	.63
No	11,041	30.5	9085	30.4
Asthma at Wave 1
Yes	5191	14.1	4266	14.0	.69
No	31,586	85.9	26,193	86.0
GERS ^a at Wave 1
Yes	11,202	30.5	9237	30.4	.67
No	25,484	69.5	21,166	69.6
PTSD ^b at Wave 1
Yes	5386	15.0	5285	18.2	<.01
No	30,629	85.1	23,690	81.8

^aGastroesophageal reflux symptoms (GERS) were defined as reported heartburn, indigestion, or reflux at the time of the Wave 1 questionnaire
^bPosttraumatic stress disorder (PTSD) was defined as a score > 44 on the 17-item, event-specific PTSD Checklist

ISSN: 1476-069X