Portuguese version of the standardized Nordic musculoskeletal questionnaire: cross cultural and reliability

To analyse the impact of overtime and extended working hours on the risk of occupational injuries and illnesses among a nationally representative sample of working adults from the United States. Responses from 10,793 Americans participating in the National Longitudinal Survey of Youth (NLSY) were used to evaluate workers' job histories, work schedules, and occurrence of occupational injury and illness between 1987 and 2000. A total of 110,236 job records were analysed, encompassing 89,729 person-years of accumulated working time. Aggregated incidence rates in each of five exposure categories were calculated for each NLSY survey period. Multivariate analytical techniques were used to estimate the relative risk of long working hours per day, extended hours per week, long commute times, and overtime schedules on reporting a work related injury or illness, after adjusting for age, gender, occupation, industry, and region. After adjusting for those factors, working in jobs with overtime schedules was associated with a 61% higher injury hazard rate compared to jobs without overtime. Working at least 12 hours per day was associated with a 37% increased hazard rate and working at least 60 hours per week was associated with a 23% increased hazard rate. A strong dose-response effect was observed, with the injury rate (per 100 accumulated worker-years in a particular schedule) increasing in correspondence to the number of hours per day (or per week) in the workers' customary schedule. Results suggest that job schedules with long working hours are not more risky merely because they are concentrated in inherently hazardous industries or occupations, or because people working long hours spend more total time "at risk" for a work injury. Strategies to prevent work injuries should consider changes in scheduling practices, job redesign, and health protection programmes for people working in jobs involving overtime and extended hours.

Reports in the literature have identified a need for internationally standardized and reliable measurements to analyse musculoskeletal symptoms. Screening of musculoskeletal disorders may serve as a diagnostic tool to evaluate the work environment. The Nordic general questionnaire is a standardized instrument used to analyse musculoskeletal symptoms in an ergonomic or occupational health context. To translate and adapt a version of the Nordic general questionnaire into Brazilian Portuguese and evaluate its reliability. The cross-cultural adaptation was performed according to internationally recommended methodology, using the following guidelines: translation; back-translation; committee review; and pretesting. First, the questionnaire was independently translated into Portuguese by two teachers and one doctor, and a consensus version was generated. Second, two other translators performed a back-translation independently from one another. This version was then submitted to a committee, consisting of six specialists in the area of knowledge of the instrument, to evaluate its equivalence to the original instrument. The final version was pretested on 20 subjects randomly selected in an outpatient clinic. Reliability was assessed by a test-retest procedure at 1-day intervals using the Kappa coefficient in a group of 40 subjects. The Kappa agreement values were calculated for each one of the four questions of the questionnaire. The agreement among the same observers was substantial, varying from 0.88 to 1, according to the Kappa values. these demonstrated strong agreement of the instrument, suggesting that the Brazilian version of the "Standardized Nordic Questionnaire" offers substantial reliability.