Algorithm parameter optimization.

<p>The algorithm was applied to homogenize the Hamza et al. cohort. The algorithm parameters were selected based on the value of the potential p-value bias test (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0048653#pone-0048653-t001" target="_blank">Table 1</a> and main text). Graph <b>a</b>) shows potential p-value bias versus % of cohort weight decrease. A 7% cohort weight decrease was selected, as weight decreases beyond this value produced only a marginal further decline in the potential p-value bias. <b>b</b>) The sphere weight parameter was set to 30. <b>c</b>) A 0.2 knocked-down weight was selected. In each of these graphs, the two parameters not represented are held at their selected values.