Sickness absence in a Singapore refinery, 1981-1992.

Sickness absence among the unionised staff of the largest petroleum refinery in Singapore was followed up from 1981 to 1992. The changes seen throughout these 12 years were related to national, organisational and personal factors. Initially because of increasing competitiveness in the industry, and later because of a national recession, manpower in the refinery was progressively reduced from 1981 to 1986. This however was not the main cause of the reduction in sickness absence rates from 8.4 working days in 1981 to 5.8 days in 1983. Organisational changes to medical leave entitlements and improved means of supervision of absence were responsible for the early fall in absence rates. Personal factors, such as the increasing age of the population, did not affect the amount of short-term absences, while shift work was associated with higher absences. From 1986 absence rates rose again, eventually to almost 1981 levels by 1992, a reflection of the tendency for sickness absence to increase with time, unless active measures are undertaken for its control.