Documentation causation

In contrast to the documented effect of cotton dust on acute responses, the causation of chronic respiratory effects in occupationally exposed subjects has not been established. The OSHA cotton dust standard is based on the premise that sustained exposure may result in chronic respiratory problems. To test this hypothesis, the pertinent literature is reviewed and discussed in an attempt to decide if convincing epidemiological documentation exists to support a cause and effect connection between prolonged dust exposure and chronic respiratory impairment. There appears to be a need for additional studies to clarify this important aspect of occupational medicine. 

However, a criticism of these studies, which can be applied to most similar papers, is that an inference of causation, i.e. that excess lead caused the documented deficits, may be unjustified. A more vigorously controlled study by Baloh et aL (1973) merely showed that a higher proportion of children in a high lead group (44% compared with 15%) were considered overactive. Concern was expressed by these authors about the difficulty of controlling or measuring such variables as, for instance, lead absorption during infancy. Problems of overcorrection for control variables may also occur. 

The documentation should be seen as an organizational asset. As there is alw s considerable effort and expense associated with workplace irrspections, not to fully utilize the information is wasteful. The reports generated through workplace inspections could identify opportunities beyond the iderrtification of hazards and accident causation factors. Inspectiorrs can also iderrtify production improvements, better maintenance techniqnes, means of reducing wastage, and increased efficiency, all of which can contribute to an improved, more productive and safer work environment. 

The 100-car study, despite its many hours of recorded data only yielded 69 crashes. This makes it a very small crash causation study. Furthermore, even die 69 crashes documented in the study were not representative of crashes in police-reported files. Thus, a contact between a vehicle backing up in a parking space until it made contact with the vehicle behind it would not be considered an accident by most drivers, would not be included in a police crash report, but would qualify as a crash in the study. On many occasions such an accident would not even quality as an imexpected event, because in small parking spaces drivers often maximize their maneuvering space by making contact with the adjacent vehicles on purpose. Indeed, in ftie 100-car study most of the crashes were of very low impact and only 12 were sufficiently severe to be reported to the police. 

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