Welding related occupational eye injuries: a narrative analysis.

OBJECTIVE: To determine the activities and circumstances proximal to a welding related occupational eye injury, a hybrid narrative coding approach derived from two well developed classification systems was developed to categorize and describe the activity, initiating process, mechanism of injury, object and/or substance, and the use of protective eyewear from the narrative text data reported for each injury. METHODS: Routinely collected workers' compensation claims over a one year period (2000) were analyzed from a large US insurance provider. An index term search algorithm of occupation, incident, and injury description fields identified 2209 potential welding related eye injury claims. After detailed review of these claims, 1353 welders and 822 non-welders were analyzed. RESULTS: During 2000, eye(s) as the primary injured body part accounted for 5% (n = 26 413) of all compensation claims. Eye injuries accounted for 25% of all claims for welders. Subjects were mainly male (97.1%) and from manufacturing (70.4%), service (11.8%), or construction (8.4%) related industries. Most injuries were foreign body (71.7%) or burn (22.2%) and 17.6% were bilateral. Common activities include welding (31.9%) and/or grinding (22.5%). Being struck by an airborne object occurred in 56.3% of cases. Non-welders showed similar patterns except that burns (43.8%) were more frequent and more often initiated by another worker (13.9%). CONCLUSIONS: Narrative injury text provides valuable data to supplement traditional epidemiologic analyses. Workers performing welding tasks or working nearby welders should be trained to recognize potential hazards and the effective use of proper safety equipment to prevent ocular injury.

A case-crossover study of transient risk factors for occupational acute hand injury.

BACKGROUND: Workers with acute hand injuries account for over 1 000 000 emergency department visits annually in the United States. AIMS: To determine potential transient risk factors for occupational acute hand injury. METHODS: Subjects were recruited from 23 occupational health clinics in five northeastern states in the USA. In a telephone interview, subjects were asked to report the occurrence of seven potential risk factors within a 90-minute time period before an acute hand injury. Each case also provided control information on exposures during the month before the injury. The self-matched feature of the study design controlled for stable between-person confounders. RESULTS: A total of 1166 subjects were interviewed (891 men, 275 women), with a mean age (SD) of 37.2 years (11.4). The median time interval between injury and interview was 1.3 days. Sixty three per cent of subjects had a laceration. The relative risk of a hand injury was increased when working with equipment, tools, or work pieces not performing as expected (11.0, 95% CI 9.4 to 12.8), or when using a different work method to do a task (10.5, 95% CI 8.7 to 12.7). Other transient factors in decreasing order of relative risk were doing an unusual task, being distracted, and being rushed. Wearing gloves reduced the relative risk by 60% (0.4, 95% CI 0.3 to 0.5). Occupational category, job experience, and safety training were found to alter several of these effects. CONCLUSION: The results suggest the importance of these transient, potentially modifiable factors in the aetiology of acute hand injury at work. Attempts to modify these exposures by various strategies may reduce the incidence of acute hand injury at work.

Case-crossover studies of occupational trauma: methodological caveats.

OBJECTIVES: The case-crossover study design was developed to examine triggers for the onset of myocardial infarction. This paper seeks to examine selected methodological issues when applying the case-crossover method to the study of traumatic injuries in the work environment. METHODS: Researchers known to be working on occupational case-crossover studies were invited to present at a workshop held at the National Occupational Injury Research Symposium in October 2000. Data from ongoing studies were used to illustrate various methodological issues involved in case-crossover studies of occupational injury. KEY FINDINGS AND ISSUES IDENTIFIED: To utilize the case-crossover design, investigators must clearly define the time during which a worker is at risk of injury, the period of time during which a particular transient exposure could cause an injury and carefully select control time periods that estimate the expected frequency of exposure. Other issues of concern are changing work tasks over time, correlated exposures over time and information bias. CONCLUSIONS AND FUTURE RESEARCH NEEDS: More case-crossover studies of occupational injury are needed to compare results from multiple studies. The validation of the timing of transient exposures relative to injury onset, whether done in a laboratory or field setting, should be conducted. Nested case-crossover designs in other epidemiological studies (case-control or cohort) can examine both transient and fixed risk factors for occupational injury, and should be attempted.

A case-crossover study of occupational traumatic hand injury: methods and initial findings.

BACKGROUND: Acute hand injury is the leading cause of occupational injury treated in United States' hospital emergency departments (e.g., laceration, crush or fracture). To identify risk factors for traumatic hand injuries, we conducted a case-crossover study of transient exposures (e.g., being rushed) for acute occupational traumatic hand injury. METHODS: The case-crossover method, which uses subjects as their own controls, was used to identify risk factors for occupational hand injury. Two hundred and thirty-two subjects were recruited from 17 occupational health clinics in New England and interviewed by telephone a median of 1.2 days after their injury. The a priori hazard period was defined as 10 min before the injury. Two control periods were used: one was 60-70 min prior to the injury (matched-pair interval analysis); the other was the total work-time exposed, on average, in the previous month (usual frequency analysis). RESULTS: In the usual frequency analysis, the relative risk for using malfunctioning or different-from-usual equipment or tools in the hazard period was 25.5 (95% confidence interval = 18.4-35.2). Relative risks were also significantly elevated for performing a task using an unusual work method, doing an unusual task, being distracted, or being rushed. Wearing gloves appeared to be protective (relative risk = 0.8, 95% CI = 0.5-1.2). Matched-pair interval analysis, where appropriate, provided similar findings but had much wider confidence intervals. CONCLUSIONS: This study demonstrates that the case-crossover design is a feasible and efficient method for studying transient risk factors for sudden-onset traumatic occupational hand injury. The usual frequency analysis proved more useful than the match-pair approach to control period selection.

Estimates of blood pressure variability in adolescents using an automatic blood pressure measuring device.

Knowledge of BP variability is important for BP screening and for the design of studies with BP as an outcome. We calculated estimates of the between-visit and within-visit variances from data obtained using an automated BP.device (Dinamap) in 776 students, aged 13-17 years, in the Exeter-Andover Project. Each subject had his or her BP measured three times per visit at up to 24 weekly visits. We compared these estimates of variance with those published for adolescents using a standard mercury sphygmomanometer. For subjects measured using the Dinamap, the between-visit variance was greater for SBP and the within-visit variance for both pressures was almost three times greater than for subjects measured with the standard instrument.

Influence of parents' physical activity levels on activity levels of young children.

To determine the relationship between activity levels of parents and those of their young children, we monitored physical activity with a mechanical device, the Caltrac accelerometer, in one hundred 4- to 7-year-old children and in 99 of their mothers and 92 of their fathers. During 1 year in the Framingham Children's Study, data were obtained for an average of more than 10 hours per day for 8.6 +/- 1.8 days for the children, for 8.3 +/- 2.1 days for their mothers, and for 7.7 +/- 2.3 days for their fathers. Children of active mothers (average Caltrac accelerometer counts per hour greater than the median) were 2.0 times as likely to be active as children of inactive mothers (95% confidence interval = 0.9, 4.5); the relative odds ratio of being active for the children of active fathers was 3.5 (95% confidence interval = 1.5, 8.3). When both parents were active, the children were 5.8 times as likely to be active (95% confidence interval = 1.9, 17.4) as children of two inactive parents. Possible mechanisms for the relationship between parents' and child's activity levels include the parents' serving as role models, sharing of activities by family members, enhancement and support by active parents of their child's participation in physical activity, and genetically transmitted factors that predispose the child to increased levels of physical activity.