TABLE 1—

Demographic and Occupational Characteristics of Participants in the Taxi Drivers’ Health Study (TDHS) and Other Drivers^a: Taipei, Taiwan, 2000

	TDHS Participants (N = 1242)		Other Drivers (N = 1940)
Characteristics	n1	Mean ± SD or %	n2	Mean ± SD or %	Reference Groupb
Age, y	1242	44.5 ± 8.7	1403	46.6 ± 8.7	43.9
Professional seniority, y	1234	11.4 ± 7.8	1890	11.0 ± 7.5	9.2
Total driving per month, days	1239	26.2 ± 2.6	1780	25.2 ± 3.6	26.8
Total driving per day, h	1238	9.8 ± 2.8	1889	9.9 ± 2.5	10
Body mass index, kg/m2	1242	24.9 ± 3.6	1780	25.2 ± 3.6	. . .
Gender
Male	1193	96%	1854	96%	97%
Female	49	4%	82	4%	3%
Education
Less than high school	405	33%	770	40%	. . .
High school	782	63%	1067	56%	. . .
College or more	53	4%	69	4%	. . .
Marital status
Single	201	16%	257	14%	. . .
Married	960	75%	1469	77%	. . .
Separated/divorced/widowed	116	9%	178	10%	. . .
Registration type
Individual	497	40%	808	43%	. . .
Cooperative	395	32%	606	33%	. . .
Affiliated with taxicab company	341	28%	447	24%	. . .
Lifting activities
Never/rare/seldom	604	49%	. . .	. . .	. . .
Often/sometimes	508	41%	. . .	. . .	. . .
Very frequently	122	10%	. . .	. . .	. . .
Bending/twisting
Never/rare/seldom	643	52%	. . .	. . .	. . .
Often/sometimes	482	39%	. . .	. . .	. . .
Very frequently	111	9%	. . .	. . .	. . .
Leisure-time physical exertion
Never/rare/seldom	602	49%	. . .	. . .	. . .
Often/sometimes	506	41%	. . .	. . .	. . .
Very frequently	126	10%	. . .	. . .	. . .
Perceived job stress
None	282	23%	. . .	. . .	. . .
Mild	639	52%	. . .	. . .	. . .
Moderate to severe	311	25%	. . .	. . .	. . .
Mental health score (0–100)	1218	63.1 ± 16.8	. . .	. . .	. . .
Job dissatisfaction index (0.01–1.00)	1225	0.61 ± 0.17	. . .	. . .	. . .
Low back pain in past 12 months	628 (1241)	51%	988 (1798)	55%	. . .
Knee pain in past 12 months	234 (1241)	19%	395 (1798)	22%	. . .

Note. n1 = number of subjects in TDHS group; n2 = number of subjects not in study base. The total number summed up across each category varies slightly because of missing data.

^aOther drivers received medical examinations at hospitals outside the study.

^bData from Dept of Statistics, Ministry of Transportation and Communication, Taiwan.58