1984 Volume 39 Issue 3 Pages 621-632
A surveillance system for gathering and analyzing working environment measurement records as well as the medical examination records kept in most workplaces every year has been implemented. To these records, the system planners added medical certificate data presented to workplaces when the workers take sick leaves for more than a fixed period of time, usually over 7 days stipulated in the enterprise regulations. The types of medical problems on the medical certificate forms are transformed into numerical codes based on the International Classification of Diseases (I. C. D.), and a frequency order of medical problems, an average of the absent days and mean age of each problem are acquired.
It was observed that the most frequent problem was due to injuries, followed by digestive ulcers, spinal disorders and respiratory diseases. Three months and 10 days, for unspecified tumors and respiratory diseases respectively, different periods of absent time for each problem and 35 days of total problems were ascertained. Hypertension and spondylosis were high on the average due to age and threatened abortion the lowest conversely. In addition, 4 clusters of workplaces are classified by the cluster analysis employing absent rates of specific disease groups and are explicated for various aspects due to the results of chi square test.
Characteristics of the 4 disease group patterns of clusters are as follows.
1) Pattern I, including 67% of the workplaces and displaying a pattern of low level controlled absent rates with all disease groups, has a distinctive feature in that the woman worker's ratio is higher than the average and the work environment is rather good.
2) A small number of workplaces, Pattern II, shows an interesting pattern of frequent tumors and cardiovascular diseases. It contains many minor workplaces on the scale, with a large amount of the enterprises in the wood-making and ceramics industry.
3) It was found that large-scale workplaces like the transport machine industry can be classified into Pattern III which has the high absent rates due to mental disorders and piles.
4) The workplace of Pattern IV indicating a bad condition in the working environment measurement shows a relatively high absent rates for most disease groups.
