Table 1. Demographic characteristics for all subjects working as sewing machine operators in Los Angeles, California (n  = 520).

Variable	Category	Number	%*
Gender	Female	335	64.4
	Male	185	35.6
Age group	Mean (SD)	37.7	(9.9)
	<30	121	23.3
	30–39	176	33.8
	40–49	153	29.4
	⩾50	70	13.5
Ethnicity	Asian/Pacific Islander	147	28.3
	Hispanic	349	67.1
	Caucasian	24	4.6
Educational level	Primary	235	45.2
	High school	261	50.2
	University or more	23	4.4
Marital status	Living alone	110	21.2
	Cohabitating but not married	110	21.2
	Married but separated	75	14.4
	Married and living with spouse	166	31.9
Living with children	No children	120	23.1
	Equal or less than 5 years of age	157	30.2
	More than 5 years of age	243	46.7
Supporting other family members	No	235	45.2
outside of their own household	Yes	285	54.8
Body mass index (BMI)	Mean (SD)	26.2	(4.8)
	Underweight (<18.5 kg/m2)	6	1.2
	Normal (18.6–24.9 kg/m2)	195	37.5
	Overweight (25–29.9 kg/m2)	203	39.0
	Obese (>29.9 kg/m2)	83	16.0
Non-work-related physical activity	None	194	37.3
	Less than once per week	34	6.5
	Once or twice per week	171	32.9
	Three or more times per week	121	23.3
Smoking behaviour	Non-smoker	441	84.8
	Past smoker	54	10.4
	Current smoker	25	4.8
Medical history of systemic illness†	None	443	85.2
	Any	77	14.8
Medical history of musculoskeletal disorders	None	468	90.0
	Any	52	10.0
Years lived in the United States	Mean (SD)	12.0	(7.2)
	<5 years	109	21.0
	5–10 years	103	19.8
	10–20 years	148	28.5
	>20 years	160	30.8
English-speaking ability	None at all	117	22.5
	Only a few words	357	68.7
	Enough to get by or very well	46	8.8
Years of employment in garment industry	Mean (SD)	11.1	(7.3)
	<7	154	29.6
	7–10	106	20.4
	11–15	152	29.2
	>15	108	20.8

* Some percentages do not total 100 because of rounding; † the list of systemic illnesses or diseases included: diabetes (excluding diabetes solely related to pregnancy), rheumatoid arthritis, lupus erythematodes, degenerative arthritis (osteoarthritis), low thyroid or overactive thyroid, chronic renal failure, and gout.