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Effect Size And Power For Clinical Trials Using Years Of Healthy Life As The Primary Endpoint, Paula Diehr Jun 1997

Effect Size And Power For Clinical Trials Using Years Of Healthy Life As The Primary Endpoint, Paula Diehr

Paula Diehr

Some clinical trials perform repeated measurements on patients over time, plot those measures against time, and summarize the results in terms of the area under the curve. If the measured variable is health status, the summary outcome is sometimes referred to as years of healthy life (YHL), or quality-adjusted life years (QALY). This paper investigates some theoretical and practical aspects of randomized trials designed to assess measures such as YHL. We first derived algebraic expressions for the effect size of YHL measures under several theoretical models of the treatment's effect on health. We used these expressions to examine how the …


Neuroendocrine Aspects Of Primary Endogenous Depression Xv. Mathematical Modeling Of Nocturnal Melatonin Secretion In Major Depressives And Normal Controls, L. Kathleen Sekula, Joseph F. Lucke, E. Kevin Heist, R. Kenneth Czambel, Robert T. Rubin Jan 1997

Neuroendocrine Aspects Of Primary Endogenous Depression Xv. Mathematical Modeling Of Nocturnal Melatonin Secretion In Major Depressives And Normal Controls, L. Kathleen Sekula, Joseph F. Lucke, E. Kevin Heist, R. Kenneth Czambel, Robert T. Rubin

Joseph Lucke

We previously reported a trend toward a higher mean nocturnal serum melatonin (MEL) concentration, based on 30-min blood sampling over 24 h, in 23 female definite endogenous depressives compared to 23 matched normal female control subjects, and no significant difference in 15 male depressives compared to their controls (Rubin et al., 1992). In both groups of patients vs. their controls, there also were trends toward an earlier MEL rise time, by about 30 min, and a later MEL peak time, by about 90 min. Because the offset of MEL secretion was not estimated in that study, the total duration of …