110879
History In 1974 , after studies of surveillance programs for coal miners revealed unacceptable degrees of reader variability , NIOSH began the " B " reader program ( so named because of the Black lung or Coal Workers ' X-ray Surveillance Program ) , with the intent to train and certify physicians in the ILO Classification system ( for classifying radiographs for the presence of pneumoconiosis ) , so as to insure that physicians using this system were as accurate and precise as possible .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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