Showing papers by "Michael A. Province published in 1986"
TL;DR: The hourly means of ionized calcium and phosphorus demonstrate significant diurnal variation with a similar apogee, nadir, and periodicity to provide more evidence of an altered mineral hemostasis in postmenopausal women.
Abstract: Serum calcium, ionized calcium, and phosphorus have been obtained at hourly intervals in nine healthy postmenopausal women. The hourly means of ionized calcium and phosphorus demonstrate significant diurnal variation with a similar apogee, nadir, and periodicity (24 hours). These results are distinct from the diurnal variation of ionized calcium and phosphorus previously reported for young men and provide more evidence of an altered mineral hemostasis in postmenopausal women.
17 citations
TL;DR: A model for a total-muscle-strength score that uses the data of the extended baseline period in the evaluation of the leucine treatment, based on a polynomial growth curve in age whose coefficients can vary according to treatment or phase is developed.
Abstract: A trial of Duchenne muscular dystrophy involved tracking boys of all ages through a one-year baseline period, followed by a one-year trial of leucine versus placebo treatment. In this paper we develop a model for a total-muscle-strength score that uses the data of the extended baseline period in the evaluation of the leucine treatment. The model is based on a polynomial growth curve in age whose coefficients can vary according to treatment or phase. Maximum likelihood estimates of the parameters of the model are obtained from use of the EM algorithm. We propose tests for the adequacy of the model as well as for treatment effects. A quadratic model appears the most parsimonious fit to the data and there is no evidence of any leucine effect on scores. We examine the asymptotic power of the test for treatment effect and compare it with that of a simpler analysis.
11 citations