Network properties can be estimated using functional connectivity MRI (fcMRI). However, regional variation of the fMRI signal causes systematic biases in network estimates including correlation attenuation in regions of low measurement reliability. Here we computed the spatial distribution of fcMRI reliability using longitudinal fcMRI datasets and demonstrated how pre-estimated reliability maps...

We read the latest paper from Torkildsen et al. with great interest and agree with the authors that their data provide a convincing empirical demonstration of the extent to which failing to correct for year and place of birth can generate false-positive associations in studies considering the role of month of birth (MOB) in multiple sclerosis. However, regarding their suggestion that these data...

Age is a potential source of variation that contributes to differences between, but not within, twin pairs. In most genetic analyses of twin data, linear and other functions of age are usually removed prior to model fitting. This correction is typically applied only within twin groups of the same sex and zygosity, and no heterogeneity test of age regressions is performed. Here we include age as...

MOTIVATION Data from one-channel cDNA microarray studies may exhibit poor reproducibility due to spatial heterogeneity, non-linear array-to-array variation and problems in correcting for background. Uncorrected, these phenomena can give rise to misleading conclusions. RESULTS Spatial heterogeneity may be corrected using two-dimensional loess smoothing (Colantuoni et al., 2002). Non-linear bet...

Minimally invasive techniques for hallux valgus correction include arthroscopy, percutaneous and minimum incision surgery. In the last few decades, several techniques have been increasingly used. We performed a comprehensive search of CINAHL, Embase, Medline, HealthSTAR and the Cochrane Central Registry of Controlled Trials, from inception of the database to 4 January 2010, using various combin...

Cone-beam CT (CBCT) images are routinely acquired to verify patient position in radiotherapy (RT), but are typically not calibrated in Hounsfield Units (HU) and feature non-uniformity due to X-ray scatter and detector persistence effects. This prevents direct use of CBCT for re-calculation of RT delivered dose. We previously developed a prior-image based correction method to restore HU values a...