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Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial.

Publication ,  Journal Article
Myers, ER; Silva, SG; Hafley, G; Kunselman, AR; Nestler, JE; Legro, RS ...
Published in: Contemp Clin Trials
June 2005

Polycystic ovary syndrome (PCOS) affects approximately 5% of the female population, and is a leading cause of infertility, primarily secondary to anovulation. Clomiphene citrate has been standard therapy for ovulation induction in patients seeking pregnancy, but recent evidence suggests that insulin sensitizing agents such as metformin may also be effective. The National Institute of Child Health and Human Development's Reproductive Medicine Network has begun a randomized, double-blind trial of clomiphene vs. metformin vs. clomiphene plus metformin for the induction of ovulation in patients with PCOS seeking pregnancy, with live birth rate as the primary outcome. Because the available literature was largely limited to surrogate outcomes such as ovulation and pregnancy rates, we created a Markov model to derive estimates of likely live birth rates in each arm. Using these estimates, we then constructed an algorithm that allowed only two formal comparisons between the three arms. First, we assumed that combination therapy would have to be superior to the next best single-agent therapy in order to be preferred, because of complexity, costs, increased side effects, etc. If combination therapy is not superior to the next best single agent, then the only other comparison of interest is between the two single agent therapies. Because the third possible comparison, between the best and worst of the three therapies, is not clinically relevant, it can be eliminated from formal statistical consideration, with subsequent reduction in sample size. Based on the opinion of the Network Steering Committee that a 15% absolute difference in live birth rates would be clinically relevant, our methodology resulted in a sample size of 226 per arm, or a total of 678 subjects. The PPCOS trial should definitively answer the question of the relative efficacy of metformin, clomiphene, and combination therapy in the treatment of infertile women with PCOS.

Duke Scholars

Published In

Contemp Clin Trials

DOI

ISSN

1551-7144

Publication Date

June 2005

Volume

26

Issue

3

Start / End Page

271 / 280

Location

United States

Related Subject Headings

  • Uncertainty
  • Treatment Outcome
  • Sample Size
  • Research Design
  • Public Health
  • Pregnancy Outcome
  • Pregnancy
  • Polycystic Ovary Syndrome
  • Ovulation Induction
  • Metformin
 

Citation

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Myers, E. R., Silva, S. G., Hafley, G., Kunselman, A. R., Nestler, J. E., Legro, R. S., & National Institute of Child Health and Human Development Reproductive Medicine Network, . (2005). Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial. Contemp Clin Trials, 26(3), 271–280. https://doi.org/10.1016/j.cct.2005.01.006
Myers, Evan R., Susan G. Silva, Gail Hafley, Allen R. Kunselman, John E. Nestler, Richard S. Legro, and Richard S. National Institute of Child Health and Human Development Reproductive Medicine Network. “Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial.Contemp Clin Trials 26, no. 3 (June 2005): 271–80. https://doi.org/10.1016/j.cct.2005.01.006.
Myers ER, Silva SG, Hafley G, Kunselman AR, Nestler JE, Legro RS, et al. Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial. Contemp Clin Trials. 2005 Jun;26(3):271–80.
Myers, Evan R., et al. “Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial.Contemp Clin Trials, vol. 26, no. 3, June 2005, pp. 271–80. Pubmed, doi:10.1016/j.cct.2005.01.006.
Myers ER, Silva SG, Hafley G, Kunselman AR, Nestler JE, Legro RS, National Institute of Child Health and Human Development Reproductive Medicine Network. Estimating live birth rates after ovulation induction in polycystic ovary syndrome: sample size calculations for the pregnancy in polycystic ovary syndrome trial. Contemp Clin Trials. 2005 Jun;26(3):271–280.
Journal cover image

Published In

Contemp Clin Trials

DOI

ISSN

1551-7144

Publication Date

June 2005

Volume

26

Issue

3

Start / End Page

271 / 280

Location

United States

Related Subject Headings

  • Uncertainty
  • Treatment Outcome
  • Sample Size
  • Research Design
  • Public Health
  • Pregnancy Outcome
  • Pregnancy
  • Polycystic Ovary Syndrome
  • Ovulation Induction
  • Metformin