NCT04240184

Brief Summary

BACKGROUND: Musculoskeletal disorders, and in particular low-back pain (LBP), are common among blue collar workers. In the work environment, both physical- and psychosocial risk factors exist. Working in warehouses in Denmark involve large quantities of occupational lifting, high work pace and a low degree of influence at work. This study investigates both acute and long-term associations between physical- and psychosocial work environmental factors and risk of LBP in warehouse workers. The specific study aims are to investigate 1) exposure-response associations between quantity of occupational lifting and short-term (day-to-day) changes in LBP, 2) the influence of accumulated workdays and rest days during a working week on LBP, 3) long-term association between occupational lifting exposure and LBP when assessed over 1 year, and 4) the role of psychological and social factors on the above associations. METHODS: The present study is designed as a 1-year prospective cohort study that will examine full-time warehouse workers from up to five retail chains in Denmark. Study aims 1 and 2 will be addressed using objective data based on company records with information on weight of all the goods handled by each warehouse worker during every single workday for 3 weeks. During this period, each worker will reply to text messages received before and after every workday (also on days off work) in which study participants will score their pain in the low back, bodily fatigue and perceived mental stress (scale 0-10). Long-term pain development is assessed using questionnaire surveys before and after 1 year. Further, pressure pain threshold (PPT) will be measured for selected trunk extensor muscles in approximately 50 workers using algometry along with measurements of maximal trunk extensor strength. Associations are modelled using linear mixed models with repeated measures between variables and LBP controlled for relevant confounders. DISCUSSION: This study provides knowledge about the acute and long-term associations between physical- and psychosocial work environmental factors and LBP. The obtained data will have the potential to provide recommendations on improved design of the working week to minimize the risk of LBP among warehouse workers, and may potentially enable to identify a reasonable maximum lifting threshold per day (ton lifted/day).

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
400

participants targeted

Target at P75+ for all trials

Timeline
Completed

Started Sep 2021

Geographic Reach
1 country

1 active site

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

January 21, 2020

Completed
6 days until next milestone

First Posted

Study publicly available on registry

January 27, 2020

Completed
1.6 years until next milestone

Study Start

First participant enrolled

September 1, 2021

Completed
1.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2022

Completed
9 months until next milestone

Study Completion

Last participant's last visit for all outcomes

September 1, 2023

Completed
Last Updated

October 31, 2022

Status Verified

October 1, 2022

Enrollment Period

1.2 years

First QC Date

January 21, 2020

Last Update Submit

October 28, 2022

Conditions

Outcome Measures

Primary Outcomes (3)

  • Short-term LBP

    exposure-response associations between quantity of occupational lifting and short-term (day-to-day) changes in LBP

    21 days

  • Accumulated workdays and LBP

    the influence of accumulated workdays and rest days during a working week on LBP

    21 days

  • Long-term LBP

    Long-term association between occupational lifting exposure and LBP when assessed over 1 year

    1 year

Secondary Outcomes (1)

  • Psychosocial influence on LBP

    21 days

Interventions

Cohort study - The specific study aims are to investigate 1) exposure-response associations between quantity of occupational lifting and short-term (day-to-day) changes in LBP, 2) the influence of accumulated workdays and rest days during a working week on LBP, 3) long-term association between occupational lifting exposure and LBP when assessed over 1 year, and 4) the role of psychological and social factors on the above associations.

Eligibility Criteria

Age18 Years+
Sexall
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Enrolled study participants will receive a baseline questionnaire by e-mail that will address various aspects of physical-, psychological and social work environment and health. The questionnaire will also comprise an invitation to participate in a text message survey. Participants recruited for the text message survey will receive a SMS text message before and after every workday for 3 full weeks (21 days) to rate the magnitude of pain in their low back, and to score their current level of perceived physical fatigue and mental stress. During the same 3-week study period, section leaders at the warehouses will provide company records about the workload of each participating warehouse worker (goods handled by each worker, weight of the goods) along with a working schedule for each worker. One year after responding to the baseline questionnaire, the participant will be receiving a follow-up questionnaire

You may qualify if:

  • working ≥30 h per week in a registered retail industry warehouse
  • ability to read and understand Danish or English,
  • ≥18 years of age.

You may not qualify if:

  • Hypertension \> 160/100 mmHg

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

National Research Centre for the Working Environment

Copenhagen, 2100, Denmark

RECRUITING

MeSH Terms

Conditions

Musculoskeletal Diseases

Study Officials

  • Lars L Andersen, PhD

    National Research Centre for the Working Environment, Denmark

    STUDY DIRECTOR
  • Runi Blafoss, MSc

    National Research Centre for the Working Environment, Denmark

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Runi Blafoss, MSc

CONTACT

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER GOV
Responsible Party
SPONSOR

Study Record Dates

First Submitted

January 21, 2020

First Posted

January 27, 2020

Study Start

September 1, 2021

Primary Completion

December 1, 2022

Study Completion

September 1, 2023

Last Updated

October 31, 2022

Record last verified: 2022-10

Data Sharing

IPD Sharing
Will not share

Locations