Lack of randomization in occupational epidemiology.
Kristensen
Petter
P
D004812:Epidemiologic Methods; D006801:Humans; D006838:Hydrocarbons; D008175:Lung Neoplasms / Q000209:etiology* / Q000401:mortality; D016273:Occupational Exposure; D011897:Random Allocation; D012537:Scandinavian and Nordic Countries / Q000453:epidemiology; D012907:Smoking / Q000009:adverse effects*
D006838:Hydrocarbons; C006647:asphalt