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]: To date, stent fractures reported have been related to aggressive post dilation.
[A]: non-adverse drug event


[Q]: INTRODUCTION: Despite high success rates with free-tissue transfer, flap loss continues to be a devastating event.
[A]: non-adverse drug event


[Q]: Photochemotherapy using psoralen and ultraviolet (UV)A irradiation (PUVA) is a useful treatment method for vitiligo.
[A]:
non-adverse drug event