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document
How to establish equivalence when data are censored : a randomized trial of treatments for B non-Hodgkin lymphoma . Interest in equivalence trials has been increasing for many years , though the methodology which has been developed for such trials is mainly for uncensored data . In cancer research we are more often concerned with survival . In an efficacy trial , the null hypothesis specifies equality of the two survival distributions , but in an equivalence trial , a null hypothesis of inequivalence H0 has to be tested . The usual logrank test has to be modified to test whether the true value r of the ratio of hazard rates in two treatment groups is at least equal to a limit value r0 . If prognostic factors have to be taken into account , the Cox model provides tests of Ho , and a useful confidence interval for the adjusted relative derived from the regression parameter for the treatment indicator . An equivalence trial of maintenance therapy was carried out in children with B non-Hodgkin lymphoma , and serves as an illustration .
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Intervention_Educational
logrank test
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Intervention_Physical
maintenance therapy
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Outcome_Mortality
survival
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Participant_Condition
B non-Hodgkin lymphoma
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Participant_Age
children
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Participant_Condition
B non-Hodgkin lymphoma