The hand dorsum was chosen because the innervation density at this site coincided with optimal resolution and separation capabilities of the TPS, and also because the surface is relatively flat, reducing confounds of skin curvature present at other potential sites of stimulation.
For each method, trait values were adjusted using 20 principal components to reduce confounding of environment with population structure.
We were able to adjust for pre-pregnancy sleep duration and sleep quality in order to reduce confounding of our associations of interest, and to examine whether change in sleep duration from pre-pregnancy to late pregnancy was an important determinant of birth outcomes.
In the present study, we used immunodeficient NOD-scid mice to reduce confounds of xenograft rejection, avoid immunosuppressant drugs, and enhance hCNS-SCns engraftment success.
Moreover, when the analyses were restricted to HPV-exposed women, defined as either HPV DNA- or sero-positive for any of the four HPV types measured, thus reducing confounding due to (levels of relevant) sexual behaviour, the magnitude of association for HPV DNA and serology of the same type became much stronger.
The problem of confounding in environmental neuroepidemiology has led some to speculate about the advantages of studying chemical or drug exposures in lower risk populations for the purpose of reducing confounding and thus strengthening associations between measures of dose and disease (e.g., Bellinger 1995).
While data from randomised controlled trials would be preferable to observational data in terms of reducing confounding, the sample sizes would not be large enough to detect the relatively rare incidence of cancer.
To expand the applicability of microfluidic Western blotting to smaller molecular mass proteins, we describe a new fabrication technique that reduces confounding interactions of the gel with large antibody probes, as well as transition to assay conditions relevant to smaller species.
The panel's criteria address a number of study design elements, including power and sample size, precise definition of phenotypes, careful steps to reduce confounding, appropriate selection of statistical methods, and close attention to quality control.
It is therefore necessary to address this issue in a prospective trial, which reduces confounding factors and allows measurement of comorbidities in a validated scoring system.
