Process evaluation of workplace interventions with physical exercise to reduce musculoskeletal disorders

Abstract

Process evaluation is important to explain success or failure of workplace interventions. This study performs a summative process evaluation of workplace interventions with physical exercise. As part of a randomized controlled trial 132 office workers with neck and shoulder pain were to participate in 10 weeks of elastic resistance training five times a week at the workplace; the 2 min group performed a single set of lateral raise to failure, and the 12 min group performed 5-6 sets with 8-12 repetitions. Participants received a single instructional session together with a training diary and manual at baseline (100% dose delivered and 100% dose received), and 59 and 57 participants, respectively, replied to the process evaluation questionnaire at 10-week follow-up. Results showed that in the 2 and 12 min groups, respectively, 82% and 81% of the participants completed more than 30 training sessions. However, two-thirds of the participants would have preferred more than a single exercise to vary between. In the 12 versus 2 min group more participants experienced the training sessions as too long (30% versus 5%). Most participants (67-92%) found the training diary and manual helpful, adequacy in a single instructional session, and satisfaction with the type of training. Among those with low adherence, lack of time (51%) and difficulties in starting exercising after illness (26%) were common barriers for regular training. Among those with low adherence, 52% felt that five training sessions per week were too much, and 29% would rather have trained a completely different kind of exercise. In conclusion, resistance training at the workplace is generally well received among office workers with neck-shoulder pain, but a one-size-fits-all approach is not feasible for all employees.

Figure 1

Training diary registrations (fidelity). Progression of resistance (a), physical exertion during training (b), repetitions per training session (c), and percentage of participants completing different number of training sessions (d) in the 2 and 12 min groups. Values are least square means (SE) or percentage of participants. ^***Significant group effect (linear mixed model, P < 0.001).

Figure 2

(a) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on the characteristics of the training program, that is, duration of exercise sessions (1st panel), training frequency (2nd panel), progression (3rd panel), and number of exercises (4th panel) in the 2 and 12 min groups. ^***Significant difference (Fisher's exact test, P < 0.001). (b) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on the characteristics of the training program, that is, duration of exercise sessions (1st panel), training frequency (2nd panel), progression (3rd panel), and number of exercises (4th panel) among those with low and high adherence. ^***Significant difference (Fisher's exact test, P < 0.001).

Figure 3

(a) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on the type of training in the 2 and 12 min groups. (b) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on the type of training among those with low and high adherence. ^***Significant difference (Fisher's exact test, P < 0.001).

Figure 4

(a) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on supportive elements related to the training program, that is, the training diary (1st panel), training manual (2nd panel), training supervision (3rd panel), and telephone and email support (4th panel) in the 2 and 12 min groups. (b) Follow-up questionnaire (satisfaction, barriers, and facilitators). Participant feedback on supportive elements related to the training program, that is, the training diary (1st panel), training manual (2nd panel), training supervision (3rd panel), and telephone and email support (4th panel) among those with low and high adherence. ^**Significant difference (Fisher's exact test, P < 0.01).

Figure 5

(a) Follow-up questionnaire (satisfaction, barriers, and facilitators). Reasons for missing exercise sessions in the 2 and 12 min groups (multiple-choice question). (b) Follow-up questionnaire (satisfaction, barriers, and facilitators). Reasons for missing exercise sessions among those with low and high adherence (multiple-choice question). ^{* , ** , ***}Significant difference (Fisher's exact test, P < 0.05, 0.01, 0.001, resp.).