Assessing differential drug effect.

D A Berry; M L Eaton; B P Ekholm; T L Fox

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PubMed · 6398711

Assessing differential drug effect.

D A Berry·M L Eaton·B P Ekholm·T L Fox

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Abstract

The regression effect gives a misleading impression of the relationship between drug or treatment effect and baseline measurement. We propose a method of adjusting for the regression effect; we also suggest a corresponding test for the differential drug effect. The likelihood ratio test for no differential drug effect is equivalent to a test for equality of variances, suggested by Pitman (1939, Biometrika 31, 9-12) and Morgan (1939, Biometrika 31, 13-19). The proposed adjustment and test are applied to an example of blood pressure data.

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D A Berry, M L Eaton, B P Ekholm, T L Fox. 1984. Assessing differential drug effect.. https://pubmed.ncbi.nlm.nih.gov/6398711/

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