Biostatistics for Radiologists

Introduction.-1 Diagnostic Performance.- 1.1. The Results of an Examination Compared to a Reference Standard.- 1.2 Measures of Diagnostic Performance.- 1.3 Sensitivity, Specificity, FN Rate and FP Rate.- 1.4 Predictive Values, Diagnostic Accuracy, and Disease Prevalence.- 1.5 Bayes' Theorem, Likelihood Ratios, and Graphs of Conditional Probability.- 1.6 Cutoff and ROC Curves.- 2 Variables and Measurement Scales, Normal Distribution, and Confidence Intervals.- 2.1 Variables and Measurement Scales.- 2.2 Gaussian Distribution.- 2.3 Basics of Descriptive Statistics.- 2.4 Standard Error of the Mean.- 2.5 Standard Error of the Difference between two Sample Means.- 2.6 Confidence Intervals.- 2.7 Confidence Interval of a Proportion.- 3 Null Hypothesis, Statistical Significance and Power.- 3.1 Null hypothesis and Principle of Falsification.- 3.2 Cutoff for Significance, Type I or a Error and Type II or ss Error.- 3.3 Statistical Power.- 3.4 Why 0.05?.- 3.5 How to Read a p Value.- 4 Parametric Statistics.- 4.1 The Foundations of Parametric Statistics.- 4.2 Comparison Between Two Sample Means: Student's t Test.- 4.2.1 The Link with Confidence Intervals.- 4.3 Comparing Three or More Sample Means:the Analysis of Variance.- 4.4 Parametric Statistics in Radiology .-5 Non-Parametric Statistics.- 5.1 One Sample with Two paired Measurements.- 5.2. Two Independent Samples.- 5.3 Three or More (k) Dependent Samples.- 5.4 Three or More (k) Independent Samples.- 5.5 Some Considerations Regarding Non-Parametric Tests.- 6 Linear Correlation and Regression.- 6.1 Association and Causation.- 6.2 Correlation between Continuous Variables.- 6.3 Interpreting the Correlation Coefficient.- 6.4 Test for Significance.- 6.5 Rank Correlation.- 6.6 Linear Regression.- 6.7 Interpreting the Regression Line.- 6.8 Limitations of the Use of the Regression Line.- 7 Reproducibility: Intraobserver