number needed to harm


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number needed to harm

The cohort of patients who must receive a specified medication in routine therapeutic use a specified adverse outcome. In the context in which the term is used, 'adverse outcome' means death or significant impairment or disability that is attributable to the specified medication.

number needed to harm

The number of patients needed to be exposed to a noxious agent or medical intervention in order that one might suffer an adverse event. This concept is important in the assessment of the relative hazard of medical interventions, the relative toxicities of poisons, or the relative value of certain experimental interventions. Generally, the smaller the value, the more dangerous the therapy or noxious agent.
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Evidence on number needed to treat and number needed to harm (if available) from systematic reviews of respiratory tract infections is presented graphically in Fig.
And comparing the number needed to treat with the number needed to harm is a fairly easy way for physicians to get an overall picture of the risk-benefit profile of a treatment.
This translates to a number needed to harm of 2,000 for every year of use; that is, 2,000 bisphosphonate users would be needed for one case of drug-related atypical fracture to occur per year.
She concluded by citing another study that showed that the number of children needed to treat with antidepressants to achieve one remission is 10, while the comparable number needed to harm due to suicidal ideation or attempts is 112 (JAMA 2007; 297: 1683-96).
The two approved treatments also have a number needed to harm in single digits.
By using the odds ratio from the meta-analysis, the investigators calculated the number needed to harm (NNH) according to varying risk factors such as ulcer drug use and hospitalization for any upper GI event.
Indeed, among the few elderly patients enrolled in large-scale trials, the risk of bleeding events was high enough that the number needed to treat (46) was close to the number needed to harm (55).
The researchers estimated that the number needed to harm with TZDs is about 50 patients over a 2.