title: Epidemiology of acute low back injury in employees of a large home improvement retail company.
abstract: Acute low back injuries are described in a cohort of about 31,000 material handlers employed in all Home Depot, Inc., retail stores in California from 1990 through 1994. With over 87 million work hours, incidence density rates, rate ratios, and confidence intervals are given by age, sex, length of employment, and job-lifting requirements. Injuries are further described by lost work days, activity at time of injury, work restrictions, and time frames. The unadjusted low back injury rate per million work hours was 1.6 times higher for men compared with women, and rates were highest for those less than 25 years of age, those with less than 2 years of current job experience, and employees with the greatest materials lifting and handling job requirements. These findings in unadjusted rates and rate ratios persisted when each was adjusted through a Poisson regression model, with the exception of sex. The adjusted risk ratio for males was reversed with significantly higher risk in females when the rate ratio was adjusted for age, lifting intensity, and length of job experience. Injuries were most commonly associated with lifting activities and, while injury occurrence was highest from 10 a.m. to 4 p.m., rates were greatest during those hours when the store was closed to retail activities. Merchandise stocking that requires heavy and frequent materials handling is done during these hours. Fewer injuries than expected were reported on weekends, days with considerably less materials handling activities.
authors.affiliation: Department of Epidemiology, Southern California Injury Prevention Research Center, School of Public Health, University of California at Los Angeles 90095-1772, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Kraus
authors.forename: K B
authors.initials: KB
authors.lastname: Schaffer
authors.forename: D L
authors.initials: DL
authors.lastname: McArthur
authors.forename: C
authors.initials: C
authors.lastname: Peek-Asa
mesh_terms: D000041:Absenteeism; D000208:Acute Disease; D000328:Adult; D017677:Age Distribution; D019567:Back Injuries / Q000453:epidemiology* / Q000209:etiology; D002140:California / Q000453:epidemiology; D016009:Chi-Square Distribution; D015331:Cohort Studies; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015994:Incidence; D007587:Job Description; D017770:Lifting / Q000009:adverse effects*; D017116:Low Back Pain / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology*; D017678:Sex Distribution