A simple but useful way to assess fMRI scan qualities.
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ABSTRACT:
SUBMITTER: Power JD
PROVIDER: S-EPMC5296400 | biostudies-literature | 2017 Jul
REPOSITORIES: biostudies-literature
Publications
This short "how to" article describes a plot I find useful for assessing fMRI data quality. I discuss the reasoning behind the plot and how it is constructed. I create the plot in scans from several publicly available datasets to illustrate different kinds of fMRI signal variance, ranging from thermal noise to motion artifacts to respiratory-related signals. I also show how the plot can be used to understand the variance removed during denoising. Code to make the plot is provided with the articl ...[more]
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Project description:AimTo compare the waist related anthropometric measures like waist circumference, waist-to-height ratio (WHtR), waist - hip ratio (WHR) and body mass index (BMI) as predictors of coronary artery disease (CAD) in women.MethodsThe study included 88 women aged 40-80 years. Waist circumference, hip circumference, height, weight, age, and other covariates were collected by questionnaire. The primary endpoint was incident coronary heart disease that was reported by physician. The data was analyzed statistically using χ(2)-test for quantitative data and student t-test. The significance of the results as determined in 95.0% confidence interval.ResultsThe mean age was 59.07 ± 11.53 in the study group and 54.36 ± 10.84 in the control group. The waist circumference in the study group was higher (95.443 ± 11.187) than the control group (74.886 ± 6.672) (p < 0.001). The mean waist to hip ratio (WHR) was 0.96 ± 0.08 in the study group and 0.78 ± 0.06 in the control group (p < 0.001). The mean waist to height ratio (WHtR) was 0.62 ± 0.07 in the study group and 0.48 ± 0.04 in the control group (p < 0.001). Waist derived measures were superior to BMI in predicting CAD. The unadjusted AUC (95% Confidence Interval) was 0.008 (0.006-0.095) for WHtR, 0.001 (0.00 0.002) for waist - hip ratio, and 1 (0.323-1.766) for body mass index.ConclusionWaist related anthropometric measures are important predictors as CAD risk factors among middle-aged and older women, as compared to BMI.
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