Relationship between Employees' Management Factor of Visual Display Terminal (VDT) Work Time and 28-item General Health Questionnaire (GHQ-28) at One Japanese IT Company's Computer Worksite

Abstract

We studied 1365 male workers at a Japanese computer worksite in 2004 to determine the relationship between employees' time management factor of visual display terminal (VDT) work and General Health Questionnaire (GHQ) score. We developed questionnaires concerning age, management factor of VDT work time (total daily VDT work time, duration of continuous work), other work-related conditions (commuting time, job rank, type of job, hours of monthly overtime), lifestyle (smoking, alcohol consumption, exercise, having breakfast, sleeping hours), and the Japanese version of 28-item General Health Questionnaire (GHQ). Multivariate logistic regression analyses were performed to estimate the odds ratios (ORs) of the high-GHQ groups (>6.0) associated with age and the time management factor of VDT work. Multivariate logistic regression analyses indicated lower ORs for certain groups: workers older than 50 years old had significantly a lower OR than those younger than 30 years old; workers sleeping less than 6 h showed a lower OR than those sleeping more than 6 h. In contrast, significantly higher ORs were shown for workers with continuous work durations of more than 3 h compared with those with less than 1 h, those with more than 25 h/mo overtime compared with those with less, those doing VDT work of more than 7.5 h/day compared with those doing less than 4.5 h/day, and those with more than 25 h/mo of overtime compared with those with less. Male Japanese computer workers' GHQ scores are significantly associated with time management factors of VDT work.