Sleep quality and physical and social well-being in North American petrochemical shift workers

We modified a European questionnaire, the Standard Shiftwork Index, in syntax and length for application to workers of an American continuous operations petrochemical company in southeast Texas. Three groups of male employees--147 day workers, 107 8-hour backward rotating shift workers, and 107 12-hour shift workers--were surveyed for sleep quality, physical well-being, and time for family and personal pursuits. The groups were comparable in terms of travel time to work, marital status, age, number of children at home under the age of 18 years, history (years) of shift work, and proportion of partners working outside the home. Statistically significant group differences were detected in the mean responses between the 8-hour backward and the other groups for the indices of sleep quality, physical well-being (gastrointestinal and cardiovascular complaints), and time for family and personal pursuits. In all cases, the 8-hour backward shift work group fared worst. The differences between the groups are believed to reflect the stress of the respective work shift schedules.