We chose, however, to analyse the more stringent sample to avoid the influence of parity on the main outcome variables.
Other intrinsic difficulties include the strong mosaicism recently discovered [ 31- 33], and thus greater sequencing quality and coverage is necessary and more stringent sample selection criteria must be applied.
While model overfitting cannot be completely ruled out here, it is likely that such a strict bifurcation of samples in heat maps via two-way clustering of both gene classifiers and samples is simply a more stringent criterion than FDR 0.25, a commonly accepted threshold for GSEA.
This test case, however, shows that matching by pH is not always safe for guarding against the agonal stress confounder, whereas the empirically derived ASR values provide a more accurate assessment of the regulatory responses to near-death stress in individual samples, and allow a more stringent control.
A more stringent neutralization threshold of 80% would reclassify 14 positive samples to "equivocal," but the number of positive states would remain unchanged.
Although a greater number of samples would be necessary for a more stringent quantitative analysis, a detailed gene-expression profile was nonetheless obtained by taking advantage of a normalized measure of gene expression for each transcript (RPKM).
The mAb resin was mixed with the soluble fraction of the whole cell extract, washed with lysis buffer followed by a more stringent wash with high salt buffer, and protein was eluted by SDS sample buffer and heating.
Thus, we utilized a more stringent experimental set-up, capable of detecting altered transcriptional profiles between samples and controls more sensitively.
To evaluate the impact of a more stringent phenotype definition, we included only MI cases (n = 1,114) as a sub-sample of CAD patients in a separate analysis.
In our analyses, requiring only one EST for justifying positive expression was a potential source of FP, but the limited sampling depth of present EST data prevented us from using a more stringent threshold.
