3.3. Participant

A small-to-medium sized business enterprise was selected. The company developed and manufactured acoustic panels and speakers. According to the 2015 Periodic Health Examination at workplaces, 41.8% of the employees in this workplace were assessed to have a moderate-to-severe risk for CVD. Based on this finding, 49 workers (30 assessed to have moderate CVD risk and 19 assessed with a high risk) were selected as potential study participants. Subsequently, after obtaining permission from the business owner, a recruitment announcement for the study was made at the workplace with the help of an in-house occupational health manager and a briefing with the 49 potential participants was held to fully inform them of the study. Of the 49 individuals, 34 volunteered to participate (19 with moderate CVD risk and 13 with high CVD risk). However, during the study period, two participants left the company, and the final number of participants was 32. The CVD risk groups were determined based on the CVD risk assessment criteria established by the Korea Occupational Safety and Health Agency (KOSHA) based on the 2003 WHO International Society of Hypertension guidelines (WHO-ISH) [10] (Figure 2).

Algorithm Depicting Study Population. KOSHA: Korea Occupational Safety and Health Agency; CVD: Cardiovascular Disease.