Adverse drug reactions are appreciably harmful or unpleasant reactions resulting from an intervention related to the use of medical products, which predicts hazard from future administration and warrants prevention or specific treatment, or alteration of the dosage regimen, or withdrawal of the product. Given medical case reports extracted from MEDLINE, the task is to classify whether the case report mentions the presence of any adverse drug reaction. Classify your answers into non-adverse drug event and adverse drug event.

Q: The immune tolerance in a 12-year-old haemophilia A patient was carried out at the Faculty of Medicine, Ramathibodi Hospital, Bangkok in 1998.

A: non-adverse drug event
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Q: The results of our investigation were inconclusive, but suggested that the endoscope could have been responsible for some of the cases.

A: non-adverse drug event
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Q: Reversal of CNS-prophylaxis-related leukoencephalopathy after CSF shunting: case histories of identical twins.

A:
non-adverse drug event
****