Establishment and verification of the Chinese Musculoskeletal Questionnaire——The questionnaire is attached in the attachment / 中国职业医学

OBJECTIVE: To compile the Chinese Musculoskeletal Questionnaire(CMQ) and test its reliability and validity. METHODS: The initial CMQ was formed through studying literatures, interviewing professional workers who have work-related musculoskeletal disorders(WMSDs) and investigation with occupational health and ergonomics experts. Then, 436 and 443 manufacturing workers were selected as prediction and verification samples respectively by convensence sampling method. The reliability and validity of the CMQ were tested by item analysis, exploratory factor analysis and confirmatory factor analysis. RESULTS: i) The CMQ composed of 48 items with item analysis. ii) Nine common factors of CMQ were extracted using exploratory factor analysis, which explained 70.721% of WMSDs variance. iii) The results of confirmatory factor analysis showed that the ratio of chi-square to degree of freedom was 3.380, the comparative fit index was 0.781, the Tucker-Lewis index was 0.764, the root mean square error of approximation was 0.073, and the standardized root mean square residual was 0.068. iv) The results showed that the item reliabilities of the 9 common factors of CMQ such as upper and lower limbs posture load, neck posture load, back posture load, job demand, social support, job control, job environment, job system and job facilities were 0.205-0.841, the composite reliabilities were 0.545-0.894, and the convergence efficiencies were 0.377-0.834. The correlation coefficients between the common factors were less than its square root of the convergence validities. CONCLUSION: The CMQ has good reliability and validity, and is a reliable and effective tool for evaluating WMSDs.

Occurrence pattern of musculoskeletal disorders and its influencing factors among manufacturing workers / 北京大学学报(医学版)

OBJECTIVE@#To explore the occurrence pattern and its influencing factors of multi-site work-related musculoskeletal disorders (WMSDs) of the main affected body sites among manufacturing workers.@*METHODS@#Musculoskeletal disorders questionnaire was adopted to investigate the prevalence of WMSDs and the influencing factors among workers from four manufacturing factories in China. The case of WMSDs was defined as the one who had symptoms such as pain, numbness, discomfort, or limitation of activities in one or more of the nine body sites, including neck, shoulder, elbow, wrist/hand, upper back, lower back, hip/thigh, knee and ankle/foot during the last year, which lasted for more than 24 hours and did not completely relieve after rest. Besides, trauma, disability, other acute injuries or sequelae were excluded. The correlation of WMSDs between different body sites was estimated by the prevalence ratio (PR) calculated by log-binominal model. The influencing factors of multi-site WMSDs of the main affected body sites were analyzed by multinomial logistic regression model.@*RESULTS@#The overall prevalence rate of WMSDs was 79.7% among the manufacturing workers. The main affected body sites were lower back, neck, shoulder and upper back, of which the prevalence rates were 62.3%, 55.7%, 45.6%, and 38.7%, respectively. The PR values of WMSDs among these sites were relatively high. The prevalence of multi-site WMSDs involving these four sites at the same time was 25.2%, and that of three to four sites was 41.4%. Multinomial Logistic regression analysis suggested that influencing factors of multi-site WMSDs in 3-4 sites of neck, shoulder, upper back and lower back involved several aspects. Among these factors, females (OR=2.86, 95%CI 2.38-3.33) and individuals with job tenure of 15-19 years (OR=1.87, 95%CI 1.49-2.34) might have higher risk of disease. Biomechanical factors, such as often bending neck forward or holding neck in a forward position for long periods (OR=2.15, 95%CI 1.86-2.48), often twisting neck or holding neck in a twisted position for long periods (OR=1.64, 95%CI 1.40-1.92) and often twisting trunk heavily (OR=1.40, 95%CI 1.20-1.64) might be risk factors. In the aspect of work organization, doing the same work every day (OR=1.73, 95%CI 1.44-2.08), shortage of workers (OR=1.50, 95%CI 1.31-1.71) and often working overtime (OR=1.38, 95%CI 1.20-1.60) might increase the risk of disease. Factors, such as often standing for long periods at work (OR=0.77, 95%CI 0.65-0.91) and feeling breaks sufficient (OR=0.51, 95%CI 0.44-0.59) were suggested to be protective factors with OR<1.@*CONCLUSION@#The pre-valence rates of WMSDs in neck, shoulder, upper back, and lower back were high among manufacturing workers in this study. The correlation of WMSDs of these four sites was close in this study, and the comorbidity rate of 3-4 sites of these sites was relatively high, suggesting that there might be a multi-site occurrence pattern of WMSDs in "neck-shoulder-upper back-lower back" among manufacturing workers. The main influencing factors of this pattern included individual factors, biomechanical factors and work organization factors.

Analyzing the potential category of occurrence pattern of musculoskeletal disorders among workers in an electronic parts processing factory / 中国职业医学

OBJECTIVE: To explore the occurrence pattern of work-related musculoskeletal disorders( WMSDs) in electronic parts processing workers. METHODS: A total of 498 workers from an electronic parts processing factory were selected as study subjects by judgement sampling method. The prevalence of WMSDs in the past 1 year was investigated by using the China Musculoskeletal Questionnaire. The potential category model was used to classify the categories of WMSDs. RESULTS: The incidence of WMSDs in the past 1 year was 46. 8%( 233/498). Among them,the incidence of WMSDs involving only one site was 13. 1%( 65/498),and those involving at least 2 sites were 33. 7%( 168/498). The multi-site WMSDs were about 6-58 times of the single-site WMSDs. According to potential category analysis,the occurrence patterns of WMSDs were divided into three categories: i) cervical and shoulder occurrence group( 135 persons,27. 1%); ii) all parts group( 31 persons,6. 2%); iii) few or no site group( 332 persons,66. 7%). CONCLUSION: The occurrence of multi-site WMSDs in electronic parts processing workers were more common than the single-site. Analysis of potential category can be used to explore the occurrence pattern of WMSDs.