Biostatistics for Medical and Biomedical Practitioners, Second Edition

Basic Biostatistics for Medical and Biomedical Practitioners, Second Edition makes it easier to plan experiments, with an emphasis on sample size. It also shows what choices are available when simple tests are unsuitable and offers investigators an overview of how the kinds of complex tests that they won't do on their own work. The second edition presents a new, revised and enhanced version of the chapters, taking into consideration new developments and tools available, discussing topics, such as the basic aspects of statistics, continuous distributions, hypothesis testing, discrete distributions, probability in epidemiology and medical diagnosis, comparing means, regression and correlation. This book is a valuable source for students and researchers looking to expand or refresh their understanding of statistics as it applies to the biomedical and research fields. Based on the author's 40+ years of teaching statistics to medical fellows and biomedical researchers across a wide range of fields, it is a valuable source for researchers who need to understand more about biostatistics to apply it to their work. Introduces procedures, such as multiple regression, Poisson distribution, binomial and multinomial distributions, variance analysis, and how to design and sample clinical trials Presents a new section on ANCOVA Gives references to free online tests Includes over 200 diagrams, enabling the reader to visualize the results Discusses NHST testing in detail, its disadvantages, and how to think about probability Cover......Page 1 BASIC BIOSTATISTICS FOR MEDICAL AND BIOMEDICAL PRACTITIONERS ......Page 3 Copyright......Page 4 About the Author......Page 5 Preface......Page 6 References......Page 10 Acknowledgments......Page 11 Section I: Basic Aspects of Statistics ......Page 12 Populations and samples......Page 13 The effects of variability......Page 14 Variables and parameters......Page 15 Description......Page 16 Statistical inference......Page 17 General Approach to Study Design......Page 19 Replication and pseudoreplication......Page 21 A Brief History of Statistics......Page 23 References......Page 26 Early Use of Statistics......Page 28 Statistical Misuse......Page 29 Basic Guides to Statistics......Page 33 References......Page 34 Statistical Power......Page 39 Effect Size......Page 41 Posthoc Power Analysis......Page 46 Appendix......Page 47 Calculation of Power......Page 48 References......Page 50 Counting......Page 52 A Sorting Experiment......Page 53 Histograms and Frequency Polygons......Page 54 Transformations......Page 58 Stem and Leaf Diagrams......Page 59 Arithmetic Mean......Page 65 Median and Quantiles......Page 67 The Geometric Mean......Page 71 Harmonic Mean......Page 72 Measures of Variability......Page 73 Standard Deviation......Page 74 Interquartile Distance......Page 77 Tables......Page 79 Figures and Graphs......Page 80 Box Plots......Page 83 General Aspects......Page 84 Trimming and Winsorization......Page 85 Median Absolute Deviation......Page 87 Combining Experiments (Addition)......Page 88 Multiplying Means (Taylor, 1982)......Page 89 Three Useful Applications of the Variance......Page 90 References......Page 91 Types of Probability......Page 93 Basic Principles and Definitions......Page 94 Additional definitions......Page 95 Other definitions......Page 96 Conditional Probability......Page 99 Bayes Theorem......Page 100 Worked Problems......Page 102 References......Page 105 Section II: Continuous Distributions ......Page 106 Normal or Gaussian Curve......Page 107 The Quincunx......Page 110 Properties of the Normal Curve......Page 111 Description of the Distribution Shape......Page 114 Kurtosis......Page 116 Determining Normality......Page 117 Ungrouped Data......Page 122 References......Page 124 Central Limit Theorem......Page 126 Setting confidence limits......Page 130 Tolerance and Prediction Limits......Page 133 Reporting Results......Page 136 Graphic Representation......Page 137 References......Page 139 Exponential Distribution......Page 141 Logarithmic Distribution......Page 142 Chi-square Distribution......Page 143 Variance Ratio (F) Distribution......Page 144 References......Page 146 Outliers......Page 147 Slippage and contamination......Page 148 Dealing with outliers......Page 150 Extreme Values......Page 151 References......Page 152 Section III: Hypothesis Testing ......Page 154 Hypotheses......Page 155 Criticism of NHST......Page 161 Hypothesis Testing and Maximum Likelihood; the Bayes Factor......Page 163 Bayes Factor......Page 164 Type I Error and α......Page 165 References......Page 166 Statistical Power......Page 168 Effect Size......Page 170 Posthoc Power Analysis......Page 175 Appendix......Page 176 Calculation of Power......Page 177 References......Page 179 Section IV: Discrete Distributions ......Page 181 Permutations......Page 182 Combinations......Page 183 Worked Problems......Page 184 References......Page 185 General Formula......Page 186 Fisher's Exact Test (Fisher-Irwin Test)......Page 187 Reference......Page 188 Goodness of Fit......Page 189 Continuity Correction......Page 191 2x2 Contingency Tables......Page 192 Practical Matters......Page 197 Odds Ratio......Page 198 Cautionary Tales......Page 200 Larger Contingency Tables......Page 206 Fisher's Exact Test......Page 208 Determining Power and Sample Size......Page 211 Cochran-Mantel-Haenszel (C-M-H) Test and Confounders......Page 213 Testing for Trends in Proportions (Cochran-Armitage Test)......Page 216 Problems With R x C Tables......Page 218 Multidimensional Tables......Page 219 References......Page 222 Paired Samples: McNemars Test......Page 224 Testing Ordered Categorical Data: Kolmogorov-Smirnov (K-S) Tests......Page 227 Kolmogoro-Smirnov One-Sample Test......Page 228 Kolmogorov-Smirnov Two-Sample Test......Page 230 Two Categories......Page 232 Weighted Kappa......Page 234 References......Page 238 Introduction......Page 239 Bernoulli formula......Page 242 Fitting a binomial distribution to a set of trial results......Page 244 Continuity correction......Page 246 Comparing probabilities......Page 249 Exact confidence limits......Page 250 Multinomial Distribution......Page 251 References......Page 252 Proportions and Binomial Theorem......Page 253 Confidence Limits......Page 254 Sample Size......Page 255 Comparing Proportions......Page 256 References......Page 257 Introduction......Page 258 Relationship to the Binomial Distribution......Page 259 Goodness of Fit to a Poisson Distribution......Page 260 The Ratio of the Variance to the Mean of a Poisson Distribution......Page 263 Exact Method......Page 265 The Square Root Transformation......Page 266 Cumulative Poisson Probabilities......Page 267 Differences Between Means of Poisson Distributions......Page 268 Comparison of Counts Not Based on Same Units......Page 269 Comparing the Ratio of Two Poisson Variates......Page 271 Determining the Required Sample Size......Page 272 References......Page 274 Probability of r Successes......Page 275 Overdispersed Distribution......Page 277 References......Page 278 Section V: Probability in Epidemiology and Medical Diagnosis ......Page 280 Cohort study......Page 281 Noncohort study......Page 283 Sample size and power......Page 288 Attributable risk......Page 289 Population attributable risk......Page 290 Relative risks below 1; number needed to treat......Page 291 Differences between proportions......Page 293 Difference between proportional ratios (Proportional AR and Proportional PAR)......Page 294 References......Page 295 Further Reading......Page 296 Bayes Theorem Applied......Page 297 Sensitivity and Specificity......Page 300 Practical Issues of Screening Tests......Page 304 Spectrum Bias or Effect......Page 307 Likelihood Ratios......Page 309 Cutting Points......Page 313 ROC Curves......Page 316 Some Comments on Screening Tests......Page 321 References......Page 322 Section VI: Comparing Means ......Page 325 Paired t-Test......Page 326 Unpaired t-Test......Page 335 Unequal Variances......Page 338 Nonparametric or Distribution-Free Tests......Page 340 The Wilcoxon Signed Rank Test......Page 341 The Sign Test......Page 342 Requirements......Page 344 The Paired t-Test Implies an Additive Model......Page 346 Ranking Transforms......Page 348 The Meaning of the Mann-Whitney Test......Page 349 Problems......Page 350 References......Page 351 Cross-Over Trials......Page 352 Equivalence and Noninferiority Testing......Page 356 References......Page 359 Introduction......Page 360 Bonferroni Correction and Equivalent Tests......Page 361 Error Rates......Page 363 Extreme Multiplicity and False Discovery Rates......Page 365 Group Sequential Boundaries......Page 367 Sequential Analysis......Page 370 Adaptive Methods......Page 372 References......Page 373 Basic Test......Page 376 Requirements for Test......Page 382 Homogeneity of Variance......Page 384 Kruskal-Wallis Test......Page 386 Effect Size......Page 388 Sample Size......Page 389 Multiple Comparisons......Page 390 Studentized Range Test......Page 391 Single Step Tests......Page 393 Multiple Step Tests......Page 394 Recommendations......Page 398 Linear Combinations......Page 399 Planned Experiments......Page 400 References......Page 401 Introduction......Page 403 Two-Way ANOVA......Page 404 Additivity......Page 407 Friedman Test......Page 409 Cochrane's Q-Test......Page 410 Interaction......Page 411 Missing Data or Unequal Cell Sizes......Page 417 Nested Designs......Page 418 Model II ANOVA......Page 422 More About Repeated Measures Designs......Page 423 Bibliography......Page 425 Section VII: Regression and Correlation ......Page 426 Introduction......Page 427 Transforming Curves......Page 428 Model I Linear Regression Basics......Page 432 Additional Calculations......Page 441 Residuals......Page 442 Confidence Limits......Page 448 Comparison Methods (Basic)......Page 452 Heteroscedasticity......Page 457 The Comparison Problem (Advanced)......Page 459 Comparing Two or More Lines......Page 460 Outliers......Page 464 Leverage......Page 465 Influence......Page 466 Ratio Measurements and Scaling Factors......Page 468 References......Page 470 Inverse Prediction......Page 472 Line of Best Fit Passes Through Zero......Page 475 Errors in the X Variate......Page 476 Break Points......Page 477 Resistant Lines......Page 478 Derivation of Formulas for a Straight Line Passing Through Zero......Page 480 References......Page 481 Introduction......Page 482 P Values and Confidence Limits......Page 484 Sample Size and Power......Page 485 Spearman's Test......Page 492 Kendall's Tau Test......Page 493 Partial Correlation......Page 495 Spurious Correlation......Page 497 Reliability......Page 500 Rater Agreement......Page 501 Related Expressions......Page 503 References......Page 504 Multiple Linear Regression With Two X Variables......Page 506 Prerequisites for Multiple Regression......Page 508 Determining the ``Best ́ ́ Regression......Page 509 Which Is the Best Regression?......Page 511 Nonlinear Regression: Polynomial Regression......Page 512 Conclusions About Regression Methods in General......Page 513 Multiple Regression With Many Independent X Variates......Page 514 Analysis of Cystic Fibrosis Example......Page 518 Detecting Multicollinearity......Page 519 All Subsets Regression......Page 521 Forward Selection......Page 524 Nonlinear Regression: Polynomial Regression......Page 529 Splines......Page 532 Correcting for Multicollinearity......Page 533 Principles of Nonlinear Regression......Page 535 Dummy or Indicator Variables......Page 536 Longitudinal Regression......Page 539 References......Page 540 Introduction......Page 542 Wald-Wolfowitz Runs Test......Page 543 Up-and-Down Runs Test......Page 544 Rank von Neumann Ratio......Page 545 Ratio Measurements......Page 546 Control Charts......Page 547 Cumulative Sum Techniques......Page 549 Serial Measurements......Page 553 References......Page 554 General Principles......Page 556 Quantal Dose-Response Curves......Page 558 References......Page 560 Introduction......Page 561 Single Explanatory Variable......Page 563 Multiple Explanatory Variables......Page 566 Appropriateness of Model......Page 568 References......Page 569 Introduction......Page 570 Suitability of Poisson Regression......Page 571 Correcting for Overdispersion......Page 573 References......Page 574 Section VIII: Miscellaneous Topics ......Page 575 Introduction......Page 576 Basic Method......Page 578 Confidence Limits......Page 582 Comparison of Different Survival Curves......Page 583 Sample Size......Page 584 Calculating the Log-Rank Test......Page 585 The Hazard Function......Page 586 Hazard Ratio......Page 587 Cox Proportional Hazards Regression......Page 589 Competing Risks Analysis......Page 592 References......Page 595 Forest Graphs......Page 597 Funnel plots......Page 599 Radial Plots......Page 601 LAbbé Plots......Page 602 Appendix......Page 603 References......Page 604 Bootstrap......Page 606 Permutations (or Randomization) Test......Page 609 Monte Carlo Methods......Page 610 References......Page 611 Sampling Problems......Page 613 Randomization......Page 616 Clinical Trials......Page 619 Placebo Effect......Page 624 Alternatives to Randomized Clinical Trials......Page 625 Propensity Analysis......Page 626 References......Page 627 Chapter 4......Page 630 Chapter 6......Page 631 Chapter 11......Page 634 Chapter 13......Page 635 Chapter 14......Page 636 Chapter 15......Page 640 Chapter 16......Page 643 Chapter 17......Page 646 Chapter 18......Page 648 Chapter 19......Page 651 Chapter 20......Page 652 Chapter 22......Page 656 Chapter 25......Page 658 Chapter 26......Page 661 Chapter 27......Page 663 Chapter 35......Page 667 Glossary......Page 670 A......Page 673 C......Page 674 F......Page 676 K......Page 677 M......Page 678 N......Page 679 P......Page 680 R......Page 681 S......Page 682 T......Page 683 Z......Page 684 Back Cover......Page 685 Basic Biostatistics For Medical And Biomedical Practitioners, Second Edition, Makes It Easier To Plan Experiments, With Emphasis On Sample Size. It Also Shows What Choices Are Available When Simple Tests Are Unsuitable, And Offers Investigators An Overview Of Complex Tests That They Will Not Do On Their Own, But Need To Know How They Work. The Second Edition Presents A New Revised And Enhanced Version Of The Chapters, Taking Into Consideration New Developments And Tools Available Recently, And Discusses Topics Such As Basic Aspects Of Statistics, Continuous Distributions, Hypothesis Testing, Discrete Distributions, Probability In Epidemiology And Medical Diagnosis, Comparing Means, Regression And Correlation. The Book Is Based On The Author's 40+ Years Of Teaching Statistics To Medical Fellows And Biomedical Researchers Across A Wide Range Of Fields, And It Is A Valuable Source For Researchers Who Need To Understand More About Biostatistics To Apply To Their Work. Basic Biostatistics For Medical And Biomedical Practitioners, Second Edition Is A Valuable Source For Students And Researchers Looking To Expand Or Refresh The Understanding Of Statistics As It Applies To The Biomedical And Research Fields. Introduces Procedures Such As Multiple Regression, Poisson Distribution, Binomial And Multinomial Distributions, Variance Analysis, As Well As Designing And Sampling Clinical Trials Presents A New Section On Ancova Gives References To Free Online Tests Each Statistical Inferential Test Is Followed Immediately By A Problem, To Give Readers, The Opportunity To Perform The Test And Interpret It Includes Over 200 Diagrams, Which Enables The Reader To Visualize The Results Discusses Nhst Testing In Detail, Its Disadvantages And How To Think About Probability; The Unsafety Of Accepting P