The Likelihood of Being Helped Versus Harmed (LHH) relates the number needed to treat (NTT) versus the number needed to harm (NHH). This can be modified to take into account patient-specific frequency information and patient preferences for outcomes.



= (1 / (NTT)) / (1 / (NHH)) =

= (NHH) / (NTT)


This indicates the relative benefit from therapy as compared to the risk of being harmed.



(1) for frequency of events

(2) for severity of disease vs adverse effect


Variables the modifications:

(1) The rate that the disease will progress in the patient relative to study group (times more likely to have disease progression)

(2) The rate at which the patient will have an adverse event relative to the study group (times more likely to have an adverse event)

(3) The patient's relative comparison of disease severity vs adverse effects (how significant does the patient consider disease progression to be relative to any adverse effects)


adjusted LHH for patient variables =

= (LHH) * (rate of disease progression for patient) / (rate of adverse effects for patient) * (relative severity of disease)


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