[Preventive tests and their limits. Management before the risk of complications]

The carrying out of preventive tests (Shelley's test) is studied in the light of results obtained in cases of definite accidents, on the one hand, and in similar preventive enquiries with local anaesthetics. The positivity does not exceed 25 p. 100 of the cases during definite accidents, and 10 p. 100 during preventive tests, and as risks of error are produced in both directions, the author advises against preventive tests in the majority of cases.