Table 1.

Examples of true positive, false positive, true negative, and false negative alerts

Example type	Alert type	Interaction synopsis
True positive—agree with alert	Drug–drug interactions	Ondansetron + ciprofloxacin + patient’s corrected QT interval is 550
False positive—disagree with alert	Renal	Cephalexin 250 mg capsule every 6 h and creatinine clearance is 43
True negative—agree not to alert	Drug disease	Acute kidney failure, unspecified on patient’s active problem list + acetaminophen 500 mg tablet but patient's creatinine clearance is normal
False negative—disagree not to alert	Dosing	87-year-old patient ordered to start zolpidem 10 mg daily in the outpatient setting

True Positive (TP) – agree with alert

False Positive (FP) – disagree with alert

True Negative (TN) – agree not to alert

False Negative (FN) – disagree not to alert