Absenteeism
The World Health Organization (WHO) Health and Work Performance Questionnaire (HPQ) was used to measure health and absenteeism.42 Four items were used to assess absenteeism in relation to loss of hours of work because of physical and mental health problems. An example item is: ‘‘In the last 4 weeks, how many times did you miss an entire workday because of problems with your physical or mental health?’’ Absenteeism because of illness was recoded using categorical variables of ‘‘no absence,’’ ‘‘1 day absence,’’ and ‘‘2 days or more absence.’’ This was done to reflect the quartile-based distribution of the data.