Back injury in municipal workers: a case-control study.
OBJECTIVE
The purpose of this study was to identify factors associated with acute low back injury among municipal employees of a large city.


METHODS
For each of 200 injured case patients, 2 coworker controls were randomly selected, the first matched on gender, job, and department and the second matched on gender and job classification. In-person interviews were conducted to collect data on demographics, work history, work characteristics, work injuries, back pain, psychosocial and work organization, health behaviors, and anthropometric and ergonomic factors related to the job. Psychosocial work organization variables were examined with factor analysis techniques; an aggregate value for job strain was entered into the final model. Risk factors were examined via multivariate logistic regression techniques.


RESULTS
High job strain was the most important factor affecting back injury (odds ratio [OR] = 2.12, 95% confidence interval [CI] = 1.28, 3.52), and it showed a significant dose-response effect. Body mass index (OR = 1.54, 95% CI = 1.08, 2.18) and a work movement index (twisting, extended reaching, and stooping) (OR = 1.42, 95% CI = 0.97, 2.08) were also significant factors.


CONCLUSIONS
Results suggest that increasing workers' control over their jobs reduces levels of job strain. Ergonomic strategies and worksite health promotion may help reduce other risk factors.
Harlem Center for Health Promotion and Disease Prevention, New York, NY, USA. men11@columbia.edu
A H
AH
Myers
S P
SP
Baker
G
G
Li
G S
GS
Smith
S
S
Wiker
K Y
KY
Liang
J V
JV
Johnson
D000062:Accidents, Occupational / Q000706:statistics & numerical data; D000328:Adult; D000886:Anthropometry; D019567:Back Injuries / Q000453:epidemiology / Q000209:etiology*; D015142:Baltimore / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D012307:Risk Factors; D011795:Surveys and Questionnaires