Given the AT bias (~78%) in the mt genome of H. contortus, there is a considerable bias in codon usage.
In addition, these results may be biased by the fact that, with the exception of Brazil (males = 20 females = 18), West South Africa (55∶49) and Mayotte/Comoros (57∶18), there is a considerable sampling bias toward males on these breeding grounds [84] (see Table 1).
This led to the assumption that there was a considerable systematic bias regarding the retrospective documentation of food intake in the case control studies.
Although it can be expected that IP might bring more favorable outcomes than EP, especially in the HBP subgroup, there was a considerable confounding bias between chemotherapy regimens and primary sites.
If the sequencing platform requires the incorporation of linkers and involves a PCR amplification step, this can be a considerable source of bias [ 3, 4], and it is advisable to keep the number of cycles as low as possible.
For larger genomes, such as humans, a considerable bias could be observed for 35 bp reads.
A polyA-based priming step in many labeling protocols for microarray hybridization is an example: It leads to a considerable 3' bias [ 29].
In general, a considerable bias reduction has been obtained by using our bias-corrected estimator.
In this section, studies were distinguished by route of administration as this appears to be a considerable source of confounding bias [ 45].
This limits the risk of differential recall bias; however, there is a considerable risk of non-differential recall bias driving effect measures towards the null.
