Stress and Musculoskeletal Health in Employees

Heart Rate Variability (HRV) has been widely used as an indicator for work-related stress. It measures the variation in time between each heartbeat and is controlled by the autonomic nervous system.

Salivary cortisol has been used as an indicator for stress. Pre-post intervention differences between diurnal circadian rhythm in the saliva cortisol of the participants will be measured, in order to evaluate the efficiency of the intervention upon homeostatic load.

Musculoskeletal symptoms will be assessed with the Nordic Musculoskeletal Questionnaire (NMQ). NMQ is a standardized questionnaire for the assessment of musculoskeletal problems in nine different body regions (neck, shoulders, upper back, elbows, wrist/hands, lower back, hips/thighs, knees, ankles/feet). General questions include 40 forced-choice items where responders could indicate if they had musculoskeletal problems (aches, pain, discomfort) in the last 12 months or seven days. Additional questions ask the participants to report if the musculoskeletal problems had led to inability to perform daily tasks and normal activities.

Work-related stress can lead to physical strain, which in turn can lead to musculoskeletal tension and disorders. Musculoskeletal disorders (MSDs) are a common type of occupational diseases and have become the main cause of absenteeism and early retirement in the working population.

Quality of life will be measured with the Short Form survey (SF-36) self-report questionnaire. SF-36 provides comprehensive information of an individual health status and assesses eight domains of health such as: Physical functioning, Role limitations due to physical health, Role limitations due to emotional problems, Energy/ fatigue (vitality), Emotional wellbeing, Social functioning, Pain, and General health. It provides valuable insights into participants' perceived health status and overall quality of life. All questions are scored on a scale from 0 to 100, reflecting a range from lowest to highest possible quality of life.

Scoring the SF-36 involves a two-step process. At first each question must be pre- coded with a numeric value which is then recorded according to a scoring key and then the second step involves averaging the recorded values from items within the same scale to compute the total scale score.

Psychosocial work-related stress factors will be measured with the Copenhagen Psychosocial Questionnaire (COPSOQ-II medium version). The medium version of the questionnaire consists of 8 domains, 28 dimensions and 87 items. Each item scores from 0-100 (i.e. 0, 25, 50, 75, and 100 for a five response category item). The scale score is computed as the mean item score. Higher total score indicates that the employee experiences greater work-related psychosocial risk factors.

Perceived stress will be measured with the Perceived Stress Scale (PSS-14), which is a self-report questionnaire with 14 items. It measures the perception of stressful experiences of the responder by rating the frequency of the feelings and thoughts related to events over the past month. Between items half of them are considered negative and the other as positive. Each answer responds on a five point Likert-type scale (0-never to 4=very often). Total score ranges from 0-56 and higher scores indicate greater perceived stress.

Depression, Anxiety and Stress parameters will be measured with the Depression Anxiety Stress Scales (DASS-21), which is a self-reported questionnaire designed to measure the emotional states of depression, anxiety and stress. It consists of three subscales of depression, anxiety and stress. Each subscale consists of seven items which are answered on a 4-point Likert-type scale. the answers ranging from 0 ("does not apply to me at all") to 3 ("applies to me very much") scales. The score of each subscale has to be multiplied by 2 to obtain the total subscale scores. The total scores of each subscale range from 0 to 42 points, with higher scores indicating more severe depression/anxiety/stress symptoms.