Background: Chronic musculoskeletal pain is prevalent among laboratory technicians and
work-related stress may aggravate the problem.
Objectives: This study investigated the effect of a multifaceted worksite intervention on pain
and stress among laboratory technicians with chronic musculoskeletal pain using individually
tailored physical and cognitive elements.
Study Design: This trial uses a single-blind randomized controlled design with allocation
concealment in a 2-armed parallel group format among laboratory technicians. The trial
“Implementation of physical exercise at the Workplace (IRMA09) – Laboratory technicians“
was registered at ClinicalTrials.gov prior to participant enrolment.
Setting: The study was conducted at the head division of a large private pharmaceutical
company’s research and development department in Denmark. The study duration was March
2014 (baseline) to July 2014 (follow-up).
Methods: Participants (n = 112) were allocated to receive either physical, cognitive, and
mindfulness group-based training (PCMT group) or a reference group (REF) for 10 weeks at the
worksite. PCMT consisted of 4 major elements: 1) resistance training individually tailored to the
pain affected area, 2) motor control training, 3) mindfulness, and 4) cognitive and behavioral
therapy/education. Participants of the REF group were encouraged to follow ongoing company
health initiatives. The predefined primary outcome measure was pain intensity (VAS scale 0 –
10) in average of the regions: neck, shoulder, lower and upper back, elbow, and hand at 10
week follow-up. The secondary outcome measure was stress assessed by Cohen´s perceived
stress questionnaire. In addition, an explorative dose-response analysis was performed on the
adherence to PCMT with pain and stress, respectively, as outcome measures.
Results: A significant (P < 0.0001) treatment by time interaction in pain intensity was observed
with a between-group difference at follow-up of -1.0 (95%CI: -1.4 to -0.6). No significant
effect on stress was observed (treatment by time P = 0.16). Exploratory analyses for each body
region separately showed significant pain reductions of the neck, shoulders, upper back and
lower back, as well as a tendency for hand pain.
Within the PCMT group, general linear models adjusted for age, baseline pain, and stress levels
showed significant associations for the change in pain with the number of physical-cognitive
training sessions per week (-0.60 [95%CI -0.95 to -0.25]) and the number of mindfulness
sessions (0.15 [95%CI 0.02 to 0.18]). No such associations were found with the change in stress
as outcome.
Limitations: Limitations of behavioral interventions include the inability to blind participants
to which intervention they receive. Self-reported outcomes are a limitation as they may be
influenced by placebo effects and outcome expectations