Upper arm elevation and repetitive shoulder movements: a general population job exposure matrix based on expert ratings and technical measurements.
OBJECTIVE
We recently constructed a general population job exposure matrix (JEM), The Shoulder JEM, based on expert ratings. The overall aim of this study was to convert expert-rated job exposures for upper arm elevation and repetitive shoulder movements to measurement scales.


METHODS
The Shoulder JEM covers all Danish occupational titles, divided into 172 job groups. For 36 of these job groups, we obtained technical measurements (inclinometry) of upper arm elevation and repetitive shoulder movements. To validate the expert-rated job exposures against the measured job exposures, we used Spearman rank correlations and the explained variance[Formula: see text] according to linear regression analyses (36 job groups). We used the linear regression equations to convert the expert-rated job exposures for all 172 job groups into predicted measured job exposures. Bland-Altman analyses were used to assess the agreement between the predicted and measured job exposures.


RESULTS
The Spearman rank correlations were 0.63 for upper arm elevation and 0.64 for repetitive shoulder movements. The expert-rated job exposures explained 64% and 41% of the variance of the measured job exposures, respectively. The corresponding calibration equations were y=0.5%time+0.16×expert rating and y=27°/s+0.47×expert rating. The mean differences between predicted and measured job exposures were zero due to calibration; the 95% limits of agreement were ±2.9% time for upper arm elevation >90° and ±33°/s for repetitive shoulder movements.


CONCLUSIONS
The updated Shoulder JEM can be used to present exposure-response relationships on measurement scales.
Department of Occupational Medicine, Danish Ramazzini Centre, Aarhus University Hospital, Aarhus, Denmark.
Annett
A
Dalbøge
Occupational and Environmental Medicine, University and Regional Laboratories Region Scania, Lund, Sweden Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
Gert-Åke
GÅ
Hansson
Department of Occupational Medicine, Danish Ramazzini Centre, Aarhus University Hospital, Aarhus, Denmark.
Poul
P
Frost
Department of Occupational Medicine, Danish Ramazzini Centre, Regional Hospital West Jutland-University Research Clinic, Herning, Denmark.
Johan Hviid
JH
Andersen
Department of Occupational and Environmental Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.
Thomas
T
Heilskov-Hansen
Department of Occupational Medicine, Danish Ramazzini Centre, Regional Hospital West Jutland-University Research Clinic, Herning, Denmark.
Susanne Wulff
SW
Svendsen
D000328:Adult; D001132:Arm; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D009784:Occupational Diseases / Q000209:etiology; D016273:Occupational Exposure / Q000009:adverse effects / Q000032:analysis*; D012782:Shoulder; D019534:Shoulder Impingement Syndrome / Q000209:etiology; D014937:Work
Exposure modelling; Job exposure matrix; Occupation; Shoulder