adverse event
bad outcome during experimental treatment
infection
invasion of and multiplication in a host by disease-causing pathogens or organisms, and the reaction of host tissues
adverse drug reaction
unintended effect due to administration of one or more drugs
serious adverse event
untoward medical occurrence in human medical trials that is sufficiently serious and meeting criteria such as resulting in death, life-threatening situation, inpatient hospitalization, disability or incapacity, birth defect, or permanent impairment
near miss
unplanned event that has the potential to cause, but does not actually result in human injury, environmental or equipment damage