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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NA: not applicable as the rate observed with medication is lower than that observed with placebo; NNH: number needed to harm Table 2 Number needed to harm vs placebo for weight gain, somnolence, and akathisia NNH for weight gain [greater than or equal to] 7% Bipolar Adjunctive Antipsychotic Schizophrenia mania for MDD Aripiprazole 21 ND 22 Brexpiprazole 17 52 Cariprazine 34 ND (to 6 mg/d) NNH for somnolence adverse events Bipolar Adjunctive Antipsychotic Schizophrenia mania for MDD Aripiprazole 20 20 50 Brexpiprazole 50 34 Cariprazine 100 25 (to 6 mg/d) NNH for akathisia adverse events Bipolar Adjunctive Antipsychotic Schizophrenia mania for MDD Aripiprazole 25 12 5 Brexpiprazole 112 15 Cariprazine 15 7 (to 6 mg/d) Reproduced with permission from Citrome L.
The increased risk of ectopic pregnancy (HR, 1.09) with overall primary C-sections translated to an absolute risk increase of 0.1% and number needed to harm of 1,000 women.
Rates of adverse events were higher in the gabapentinoid groups than in the placebo group, including dizziness (risk ratio, 1.99; 95% CI, 1.17-3.37; number needed to harm, 7), fatigue (RR, 1.85; 95% CI, 1.12-3.05; [I.sup.2] = 0; NNH, 8), difficulties with mentation (RR, 3.34; 95% CI, 1.54-7.25; NNH, 6), and visual disturbances (RR, 5.72; 95% CI, 1.94-16.91; NNH, 6).
(2,3) In the acute MDD trials, 32.6% of brexpiprazole-treated patients and 10.7% of placebo-treated patients discontinued because of AEs, (4,5) yielding a number needed to harm (NNH) of 53 (95% CI, 30-235).
Investigators defined the number needed to harm (NNH) as the number of dementia patients who would need to be on one of the medications for 180 days in order to result in one additional death compared with nonuser matched controls.
The number needed to harm (NNH) is calculated in the same way.
For most patients, describing the risks in hormone therapy users and nonusers as 38/10,000 and 30/10,000 is more meaningful than trying to make decisions based on a relative risk increase of 26% and a number needed to harm of 1,285.
Adverse events were reported more often in the amitriptyline group than in the melatonin group (46 vs 16; P<.03) with daytime sleepiness being the most frequent complaint (41% of patients in the amitriptyline group vs 18% of the melatonin group; number needed to harm [NNH]=5).
In contrast, the number needed to harm by causing emergence of a drug-resistant strain of HIV was 1,844, reported Dr.
* for every medication used, the calculation and clinical implications of number needed to treat (NNT) and number needed to harm (NNH).
The risk-benefit ratio of SLIT for allergic rhinitis in the pooled analysis was favorable as reflected in a number needed to harm of 303, with harm defined as a treatment-related systemic allergic reaction.
Walkup said, the number needed to harm for suicidality is around 143.