Table 4.
Study characteristics and main results of the included primary studies
| Author, year | Design | Country | Study population | Outcome | Exposition | Main results from multivariate analyses (95 % Confidence Interval) | Confounder | Quality |
|---|---|---|---|---|---|---|---|---|
| Burt et al. 2011 [48] | CS (baseline) | US | n = 464 workers from hospital servicea, engine and bus plant workplaces | Abnormal NCS + symptoms (hand diagram) | ACGIH TLV for HAL; Exertion/min. or time in %)b; Peak force (% time)c; Flexion/Extension (% time)d; Vibration (observed yes/no) | Peak force ≥20 % vs. <20 %: OR 1.3 (0.6–3.0); peak force ≥70 % vs. <20 %: OR 2.7 (1.3–5.7); exertion ≥15/min vs. <10/min if BMI ≥30: OR 3.4 (1.1–9.9); perceived exertion (unit increase): OR 1.14 (1.0-1.3); ≥AL- < TLV vs. <AL: OR 2.3 (0.6-8.9); ≥TLV vs. <AL: OR 3.0 (1.5–5.8); HAL (unit increase) if male: OR 1.4 (1.1–1.8) | Sex; BMI ≥ 30; arthritis; high blood pressure | High (16/20) |
| Burt et al. 2013 [47] | Cohort (2-years) | US | n = 347 workers from hospital servicea, engine and bus plant workplaces | Abnormal NCS + symptoms (hand diagram) | ACGIH TLV for HAL; TLR; Exertion/min. or time in %)b; Peak force (% time)c; Flexion/Extension (% time)d; Vibration (observed yes/no) | Exertion/min. ≥20 % vs <20 %: HR 2.8 (1.2-6.8); exertion/min. ≥60 % vs. <20 %: HR 19.6 (6.0–64.2); TLR (unit increase): HR 1.4 (1.1-1.8) | BMI ≥ 30; job strain | High (19/20) |
| Garg et al. 2012 [49] | Cohort (6-years) | US | n = 551 workers from processing, assembly, manufacturing workplaces | Abnormal NCS + symptoms (intensity ≥25 %/d + duration ≥2 month) | ACGIH TLV for HAL; SI score | ≥AL- < TLV vs. <AL: HR 1.4 (0.6-3.8); ≥TLV vs. <AL: HR 2.0 (0.8-5.0); SI score >6.1 vs. <6.1: HR 2.5 (1.0-6.1); | Age; BMI ≥ 30; gardening; depression; co-morbidity (other MSDs; arthritis) | High (18/20) |
| Evanoff et al. 2014 [51] | Cohort (3-years) | US | n = 1107 newly hired workers from construction, technical, laboratory, clerical and hospital service workplaces | Abnormal NCS + symptoms (hand diagram) | Job title based exposure on data from O*NET (job title and requirements): repetitive motion (5-point); static/ dynamic strength (7-point) | Results for most recent jobs (≤6 months): repetitive motion: OR 3.3 (1.4–7.8); static strength: OR 4.4 (1.4–13.9); dynamic strength: OR 3.6 (1.04-12.4); | Age; sex; BMI | Moderate (13/20) |
| Bonfiglioli et al. 2013 [50] | Cohort (2-years) | IT | n = 2194 workers from factories producing domestic appliances and nursery school | Abnormal NCS + symptoms (hand diagram) | ACGIH TLV for HAL; vibration (observed yes/no) | ≥AL- < TLV vs. <AL: IRR 2.0 (1.2–3.2); ≥TLV vs. <AL: IRR 2.7 (1.5–4.9); HAL (unit increase): IRR 1.4 (1.2–1.6); peak force (unit increase): IRR 1.3 (1.1–1.6) | Age; sex; BMI; predisposing diseases (0 vs. ≥1) | High (17/20) |
| Coggon et al. 2013 [53] | CC | GB | n = 475 patients; n = 799 controls | Abnormal NCS + symptoms (duration ≥1 month) | Repeated movements of wrist >4 h/day; repeated bending of elbow >1 h/day; keyboard/ mouse use >4 h/day; vibration >1 h/day | Repeated movements: OR 1.5 (1.1–1.9); vibration: OR 2.4 (1.6–3.8) | Age; sex; BMI; ethnicity; smoking; other diseases, somatic symptoms; mental health; psychosocial factors | Moderate (9/20) |
| Goodson et al. 2014 [52] | CC | US | n = 87 patients; n = 74 controls | Abnormal NCS + symptoms | Repetition; force; repetition + force combined; vibration; total occupational exposure | Repetition: OR 1.8 (1.5–2.2) | Age, BMI, job satisfaction, vigorous exercise; exercise strain; physical activities | Moderate (12/20) |
Abbreviations: ACGIH American Conference of Governmental Industrial Hygienists, AL Action limit, BMI Body mass index, CC Case control, CS Cross-sectional, HAL Hand activity level, HR Hazard ratio, IRR Incidence rate ratio, MSD Musculoskeletal disorders, NCS Nerve conduction studies, O*NET Occupational Information Network, OR Odds ratio, SI Strain index score (overall force rating, efforts/min., duration in exertion (%), typical hand/wrist postures; speed of work (h/day)), TLR Threshold limit ratio ((Force)/((−0.78)x(HAL) + 7.78)), TLV Threshold limit value.
aWorkers in hospital from central and sterile supply, laboratory, pharmacy, engineering, surgical, kitchen, laundry and administrative support
bExertion per minute were counted from videotape (<10; 10–15; ≥15); percent of time in (forceful) exertion (0–20; 20–60; >60 %)
cForce match peak (by dynamometer) represents peak force of job as percent in maximum voluntary contraction MVC/10 (<20 %; 20–70 %; ≥70 %)
dFlexion/extension (percent of time spend in range of motion (ROM: 0–20 %; 21–40 %; >40 %)