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.

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

[EX Q]: Chronic hydroxychloroquine use associated with QT prolongation and refractory ventricular arrhythmia.
[EX A]: adverse drug event

[EX Q]: METHODS/RESULTS: This paper presents a new case of rifabutin uveitis and a review of the various published reports to date.
[EX A]:
adverse drug event