Construction of a Musculoskeletal Discomfort Scale for the Lower Limbs of Workers: An Analysis Using the Multigroup Item Response Theory

Work-related musculoskeletal disorders (MSDs) among workers in the brass-metal industry

BackgroundBrass-metal operations hold a longstanding tradition as one of the oldest cottage industries in India. In this industry, workers engage in physically demanding tasks, and the nature of the job often leads workers to assume various non-optimal postures, which can contribute to the development of musculoskeletal disorders (MSDs).Objectives: This study aimed to recognize the significant operations involved in the brass-metal industry and identify the prevalence of MSD symptoms in different body parts of brass-metal workers. Further, this study assessed the risk of MSDs associated with brass-metal operations.MethodsThis study followed a mixed-method approach. First, onsite observations and surveys were adopted to recognize the activities involved in the brass-metal industry. Second, the body map was used to identify the prevalence of MSDs among brass-metal workers. Next, the Rapid Entire Body Assessment (REBA) method evaluated the worker's postures.ResultsThe study's findings indicate a high prevalence of MSD symptoms among brass-metal workers. Furthermore, the workers involved in the clay mixing task were at high risk of developing MSDs. The most frequently affected body parts of workers involved in the brass-metal operations were shoulders, trunk, neck, legs, wrists, and hip/buttocks.ConclusionThe study provides compelling evidence supporting the need for work-cycle modifications and ergonomic design interventions to address the symptoms of MSDs experienced by brass-metal workers. The findings will serve as a valuable basis for developing guidelines and designing targeted interventions focused on preventing MSDs and enhancing the overall well-being of workers in the brass-metal industry.

Psychometric Validation of the CLN2 Quality of Life Questionnaire in Participants with CLN2 Disease Treated with Cerliponase Alfa

OBJECTIVES

This study evaluated the psychometric properties of the ceroid lipofuscinosis type 2 Quality of Life (CLN2 QoL) questionnaire.

METHODS

Data from children with CLN2 disease aged 3-16 years receiving cerliponase alfa in the BMN 190-201 and BMN 190-202 clinical studies, collected via purposive sampling, were used to assess convergent and divergent validity, internal consistency and reliability. The clinically important difference (CID) was estimated with distribution- and anchor-based methods. Descriptive and inferential statistical analyses were conducted using IBM SPSS.

RESULTS

CLN2 QoL data of 22 participants were analysed. Ceiling effects were observed in 22 items (35% threshold); no floor effects were observed. Internal consistency analysis showed good reliability (Cronbach's alpha and Omega reliability >0.7) for four domains at study completion; only one domain had good reliability at baseline. All domains had good test-retest reliability (correlation >0.5) except Feeding With G-Tube and Seizures. Convergent and divergent correlation analysis showed moderate-strong correlations (>0.4) between PedsQL and CLN2 QoL total scores, between the Pediatric Quality of Life Inventory (PedsQL) total score and most CLN2 QoL domains at baseline, and between CLN2 QoL total score and most PedsQL domains at week 97. Known groups validity showed a significant difference in means for the Behaviour domain (p = 0.05) for reasons that could not be clarified. CID was 6.79-12.94 for domains; total score CID was 6.91 using distribution-based and 6.13-13.05 using anchor-based methods.

CONCLUSIONS

This study is the first to validate the CLN2 QoL and to estimate the CID of this instrument in CLN2 patients. Our results show good validity and reliability of this tool.

The Ergonomic Behaviors Evaluation Tool (EBET) based on social cognitive theory for the assembly line workers: development and psychometric assessment

BACKGROUND

Ergonomic behaviors play a crucial role in preventing work-related musculoskeletal disorders (WMSDs). To measure these behaviors, this research aimed to develop and evaluate an ergonomic behaviors tool (EBET) based on the Social Cognitive Theory (SCT) among women workers on assembly lines (WwAL).

METHODS

The study was conducted from December 2022 to January 2023 with a focus on the psychometric assessment of EBET. Initially, a literature review and interviews were carried out to identify crucial concepts and primary items. The questionnaire's validity was evaluated using the Content Validity Ratio (CVR) and the Content Validity Index (CVI). To determine the domains of the tool, construct validity was examined by administering the items to 270 eligible women. The reliability of the tool was assessed using McDonald's Omega coefficient.

RESULTS

From a total of 67 primary items, 50 were confirmed. The study demonstrated good validity with CVR = 0.92 and CVI = 0.97, along with reliable results indicated by McDonald's Omega coefficient of 0.74. The exploratory factor analysis (EFA) revealed ten distinct dimensions: outcome expectations, outcome expectancies, normative beliefs, perceived barriers, social support, observational learning, reinforcement, behavioral skills, self-efficacy, and intention. Together, these dimensions accounted for 66.25% of the variance in the data. Additionally, the confirmatory factor analysis results supported the presence of these ten constructs and demonstrated a satisfactory fit.

CONCLUSIONS

EBET is a dependable and valid instrument for evaluating the ergonomic behaviors of workers, utilizing the principles of SCT. Researchers can employ EBET to gather data and implement suitable training interventions to enhance ergonomic behavior among WwAL. However, it is crucial to recognize that EBET may not encompass all facets of ergonomic behaviors. Therefore, it is imperative for future research to prioritize the evaluation of EBET's suitability among diverse worker populations and to consider additional dimensions of ergonomics to ensure its wider applicability and effectiveness.

Dimensional assessment of self-reported musculoskeletal symptoms by workers: A multi-case study

BACKGROUND

Work-related musculoskeletal disorders (WMSD) encompass a range of conditions affecting muscles, tendons, and nerves. Visual diagrams are widely used to identify symptoms and to generate musculoskeletal discomfort metrics. However, there is no consensus on the number of discomfort dimensions that can originate from self-reported musculoskeletal symptoms by individuals.

OBJECTIVE

This study aimed to test the fit of WMSD symptom models from workers in two samples of different sizes.

METHODS

A combination of Full-Information Item Factor Analysis (FIFA) and Item Response Theory (IRT) was utilized to analyze and test the models. The study was conducted in two samples of workers (n1 = 6944 and n2 = 420) who had their symptoms identified with the aid of a human body diagram. An analysis was conducted considering each sample's unidimensional and three multidimensional models.

RESULTS

The unidimensional model (general musculoskeletal discomfort), bi-dimensional model (discomfort in upper and lower body), and tridimensional model (discomfort in the upper limbs, lower limbs, and trunk) showed good values of factor loading and communalities, along with satisfactory item discrimination ability. Regardless of sample size, parameter estimation for IRT and FIFA proceeded without issues, presenting suitable fit parameters.

CONCLUSION

Three models were valid and reliable for more extensive and smaller samples. However, the tridimensional model was best for generating discomfort scores in body regions. Companies and safety professionals can use these findings to devise strategies to mitigate musculoskeletal pains based on perceived symptom locations.

Assessment of the musculoskeletal discomfort scale for upper limb among workers in inner Brazil

BACKGROUND

Work-related musculoskeletal disorders for upper limbs (UL-WMSDs) form a complex of occupational diseases common to many professions worldwide. UL-WMSDs are manifested in most cases by pain, resulting in musculoskeletal discomfort.

OBJECTIVE

This research aimed to evaluate the perception of musculoskeletal discomfort in workers from the interior of the Brazilian states of Alagoas and Bahia through the construction of a scale to assess musculoskeletal discomfort for upper limb.

METHODS

The discomfort assessment scale was constructed from self-reported pain symptoms by 420 workers from the inner regions of the Brazilian states of Alagoas and Bahia. The reliability and dimensionality of the collected data were analyzed by McDonald's Omega and exploratory factor analysis, respectively. Item Response Theory (IRT) was used to create parameters for the discomfort scale.

RESULTS

The musculoskeletal discomfort metric was constructed from the workers' response with six levels (varying from minimum discomfort to maximum discomfort). At the lowest level of the scale, workers indicated symptoms in the shoulders and wrists were rare. At the highest level of the scale, daily pain symptoms are reported in all regions of the upper limbs. The shoulders are the last region to develop extreme pain symptoms.

CONCLUSION

The metric was created to present satisfactory psychometric properties and capable measurement of the workers' level of musculoskeletal discomfort based on self-reported pain symptoms. Therefore, the metric can support measuring discomfort, contributing to decisions that improve a healthier occupational environment for the worker.

Cross-Cultural Adaptation, Reliability, and Validity of the Greek Version of the Fremantle Shoulder Awareness Questionnaire (FreSHAQ-GR) in Patients with Chronic Shoulder Pain

Shoulder pain is one of the most common musculoskeletal pathologies. The association of shoulder pain with impaired proprioception and bodily self-awareness called for the cross-cultural adaptation of the Fremantle Shoulder Awareness Questionnaire (FreSHAQ) in Greek. The FreSHAQ is a relatively new self-assessment 9-item scale for impaired somatic awareness in patients with shoulder pain. The study included 100 participants (54 women) between 20 and 80 years old, with chronic shoulder pain (>3 months duration), able to comprehend and speak Greek, and recruited from three private physical therapy practices. The cross-cultural adaptation process was followed to develop the Greek version of the questionnaire (FreSHAQ-GR). Further testing for construct validity via exploratory factor analysis and correlational analysis with the Shoulder Pain and Disability Index (SPADI), the Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH), the pain catastrophizing scale (PCS), a pain intensity visual analog scale (PI-VAS) in the last week, and the demographic characteristics followed. Test-retest reliability of the FreSHAQ-GR in a sub-sample of patients (n = 25) was tested upon repeated completion of the scale after a week and examined with the intraclass correlation coefficient (ICC2,1), the standard error of the measurement (SEM), and the minimum detectable change (MDC) indices. The internal consistency of the scale was also assessed. The factor analysis revealed that the scale comprised one factor relevant to shoulder awareness but with fewer items (first 6 items) than the original FreSHAQ. Additionally, the FreSHAQ-GR (both versions) demonstrated statistically significant correlations (Spearman's r) with participants' age (r = -0.31/-0.29, p < 0.002), the PI-VAS (r = 0.54/0.52, p < 0.001), the SPADI total score and both of its subscales (r = 0.39-0.45/0.34-0.39, p < 0.001), the QuickDASH (r = 0.37/0.34, p < 0.001), and the PCS (r = 0.50/0.40, p < 0.001). The questionnaire's internal consistency (Cronbach's α/McDonald's ω) was 0.833/0.827 for the 9-item and 0.871/0.867 for the 6-item FreSHAQ-GR. Test-retest reliability was excellent for both versions of the FreSHAQ-GR (ICC2,1(95% CI) = 0.97/0.98 (0.91-0.99/0.94-0.99), and with a low error margin (SEM = 1.31/0.94 and MDC95% = 3.63/2.61). Therefore, the FreSHAQ-GR (6-item version) possesses very good measurement properties and can be administered to Greek-speaking patients with chronic shoulder pain.