Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2012 Sep 6;7(9):e42367. doi: 10.1371/journal.pone.0042367

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2012 Stanhope, Skol

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

PMC Copyright notice

Power curves (red) and cost lines (blue) for the experimental conditions and (where is the disease prevalence, the population disease allele frequency, the stage 2 genotyping cost, and the ratio of controls to cases) are plotted as a function of the proportion of controls () and cases () genotyped in stage 1, holding the proportion of markers followed up in stage 2 () at their cost minimizing values of 8.5% and 0.7% respectively. In the first case (top), power curves and cost lines are symmetric about the identify line, implying that the cost minimizing design will use equal case and control allocations. In the second (bottom) they are asymmetric, implying that the cost minimizing design will have unequal case and control allocations.

Inline graphic — Power curves (red) and cost lines (blue) for the experimental conditions and (where is the disease prevalence, the population disease allele frequency, the stage 2 genotyping cost, and the ratio of controls to cases) are plotted as a function of the proportion of controls () and cases () genotyped in stage 1, holding the proportion of markers followed up in stage 2 () at their cost minimizing values of 8.5% and 0.7% respectively. In the first case (top), power curves and cost lines are symmetric about the identify line, implying that the cost minimizing design will use equal case and control allocations. In the second (bottom) they are asymmetric, implying that the cost minimizing design will have unequal case and control allocations.