All Stories

  1. An investigation into the statistical precision attainable with a distribution-free method of constructing age-dependent reference centiles

    Article • PLOS One, August 2025, PLOS

    Stefan Wellek

  2. Reference ranges: Why tolerance intervals should not be used. Comment on Liu, Bretz and Cortina-Borja, Reference range: Which statistical intervals to use? SMMR, 2021,Vol. 30(2) 523–534

    Article • Statistical Methods in Medical Research, July 2022, SAGE Publications

    Stefan Wellek

  3. Allowing for stratification in sample size planning of two-arm trials with continuous or binary outcome: Overview and tutorial

    Article • Statistical Methods in Medical Research, December 2021, SAGE Publications

    Stefan Wellek

  4. Testing for goodness rather than lack of fit of continuous probability distributions

    Article • PLOS One, September 2021, PLOS

    Stefan Wellek

  5. Reply to Andreas Boehle, Frank Kahmann, Thomas Oliver Henkel, Joerg Zimmermann and Stefan Machten’s to the Letter to the editor Re: results of a randomized trial of treatment modalities in patients with low or early-intermediate risk prostate cancer (P...

    Article • Journal of Cancer Research and Clinical Oncology, February 2021, Springer Science + Business Media

    Stefan Wellek

  6. Correction to: Results of a randomized trial of treatment modalities in patients with low or early-intermediate risk prostate cancer (PREFERE trial)

    Article • Journal of Cancer Research and Clinical Oncology, December 2020, Springer Science + Business Media

    Stefan Wellek

  7. Is the p-Value a Suitable Basis for the Construction of Measures of Evidence? Comment on “The Role of p-Values in Judging the Strength of Evidence and Realistic Replication Expectations”

    Article • Statistics in Biopharmaceutical Research, November 2020, Taylor & Francis

    Stefan Wellek

  8. Results of a randomized trial of treatment modalities in patients with low or early-intermediate risk prostate cancer (PREFERE trial)

    Article • Journal of Cancer Research and Clinical Oncology, September 2020, Springer Science + Business Media

    Stefan Wellek

  9. Termination rates and histological reclassification of active surveillance patients with low- and early intermediate-risk prostate cancer: results of the PREFERE trial

    Article • World Journal of Urology, March 2020, Springer Science + Business Media

    Stefan Wellek

  10. On powerful exact nonrandomized tests for the Poisson two-sample setting

    Article • Statistical Methods in Medical Research, January 2020, SAGE Publications

    Stefan Wellek

  11. Planning and Analysis of Trials Using a Stepped Wedge Design: Part 26 of a Series on Evaluation of Scientific Publications

    Article • Deutsches Ärzteblatt international, June 2019, Deutscher Arzte-Verlag GmbH

    Stefan Wellek

  12. Testing for goodness rather than lack of fit of an X–chromosomal SNP to the Hardy-Weinberg model

    Article • PLOS One, February 2019, PLOS

    Stefan Wellek

  13. Author response to the contributors to the discussion on “A critical evaluation of the current ‘p -value controversy’”

    Article • Biometrical Journal, June 2017, Wiley

    Stefan Wellek

  14. Sample size planning of two-arm superiority and noninferiority survival studies with discrete follow-up

    Article • Statistics in Medicine, June 2017, Wiley

    Stefan Wellek

  15. A critical evaluation of the current “p-value controversy”

    Article • Biometrical Journal, May 2017, Wiley

    Stefan Wellek

  16. Equivalence Testing With Particle Size Distribution Data: Methods and Applications in the Development of Inhalative Drugs

    Article • Statistics in Biopharmaceutical Research, January 2017, Taylor & Francis

    Stefan Wellek

  17. A U -statistics based approach to sample size planning of two-arm trials with discrete outcome criterion aiming to establish either superiority or noninferiority

    Article • Statistics in Medicine, November 2016, Wiley

    Stefan Wellek

  18. Prenatal Risk Calculation (PRC) 3.0: An Extended DoE-Based First-Trimester Screening Algorithm Allowing For Early Blood Sampling

    Article • Ultrasound International Open, February 2016, Thieme Publishing Group

    Stefan Wellek

  19. PREFERE-Studie im Aufwind

    Article • Der Urologe, February 2016, Springer Science + Business Media

    Stefan Wellek

  20. Normal Doppler Reference Values of the Pericallosal Artery

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, September 2015, Thieme Publishing Group

    Stefan Wellek

  21. Testing for noninferiority of binomial distributions referring to a modified equivalence region with piecewise linear boundary

    Article • Journal of Statistical Computation and Simulation, September 2015, Taylor & Francis

    Stefan Wellek

  22. Nearly exact sample size calculation for powerful non-randomized tests for differences between binomial proportions

    Article • Statistica Neerlandica, March 2015, Wiley

    Stefan Wellek

  23. A comparison of region-of-interest measures for extracting whole brain data using survival analysis in alcoholism as an example

    Article • Journal of Neuroscience Methods, March 2015, Elsevier

    Stefan Wellek

  24. Multivariate Equivalence Tests for Use in Pharmaceutical Development

    Article • Journal of Biopharmaceutical Statistics, June 2014, Taylor & Francis

    Stefan Wellek

  25. Determination of reference limits: statistical concepts and tools for sample size calculation

    Article • Clinical Chemistry and Laboratory Medicine (CCLM), January 2014, De Gruyter

    Stefan Wellek

  26. Biometry of the fetal corpus callosum by three‐dimensional ultrasound

    Article • Ultrasound in Obstetrics and Gynecology, November 2013, Wiley

    Stefan Wellek

  27. The Place of Additional Individual Psychotherapy in the Treatment of Alcoholism: A Randomized Controlled Study in Nonresponders to Anticraving Medication—Results of the PREDICT Study

    Article • Alcoholism Clinical and Experimental Research, November 2013, Wiley

    Stefan Wellek

  28. Advanced dynamic Doppler flow of the pulmonary artery in a normal population: reference values from 18 to 41 weeks of gestation calculated by automatic Doppler waveform analysis

    Article • Archives of Gynecology and Obstetrics, November 2013, Springer Science + Business Media

    Stefan Wellek

  29. PREFERE – die Deutsche Prostatakrebsstudie

    Article • Der Urologe, August 2013, Springer Science + Business Media

    Stefan Wellek

  30. PREFERE – die Deutsche Prostatakrebsstudie

    Article • Der Urologe, August 2013, Springer Science + Business Media

    Stefan Wellek

  31. Die Bedeutung der Pathologie in der deutschen Prostatakrebsstudie PREFERE

    Article • Der Pathologe, August 2013, Springer Science + Business Media

    Stefan Wellek

  32. Implementing Panic-Focused Psychodynamic Psychotherapy into Clinical Practice

    Article • The Canadian Journal of Psychiatry, June 2013, SAGE Publications

    Stefan Wellek

  33. PREFERE – die Deutsche Prostatakrebsstudie

    Article • Der Urologe, April 2013, Springer Science + Business Media

    Stefan Wellek

  34. Results of a double-blind, placebo-controlled pharmacotherapy trial in alcoholism conducted in Germany and comparison with the US COMBINE study

    Article • Addiction Biology, December 2012, Wiley

    Stefan Wellek

  35. Establishing Equivalence or Non-Inferiority in Clinical Trials

    Article • Deutsches Ärzteblatt international, October 2012, Deutscher Arzte-Verlag GmbH

    Stefan Wellek

  36. A combination of galantamine and memantine modifies cognitive function in subjects with amnestic MCI

    Article • The journal of nutrition health & aging, June 2012, Elsevier

    Stefan Wellek

  37. On the Proper Use of the Crossover Design in Clinical Trials

    Article • Deutsches Ärzteblatt international, April 2012, Deutscher Arzte-Verlag GmbH

    Stefan Wellek

  38. Blood Flow Velocity Waveforms of the Umbilical Artery in a Normal Population: Reference Values from 18 Weeks to 42 Weeks of Gestation

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, February 2012, Thieme Publishing Group

    Stefan Wellek

  39. Reference Values for Blood Flow Velocity in the Uterine Artery in Normal Pregnancies from 18 Weeks to 42 Weeks of Gestation Calculated by Automatic Doppler Waveform Analysis

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, January 2012, Thieme Publishing Group

    Stefan Wellek

  40. Cochran-Armitage Test versus Logistic Regression in the Analysis of Genetic Association Studies

    Article • Human Heredity, December 2011, Karger Publishers

    Stefan Wellek

  41. Fetal Lung Volume Measurements using 3D Ultrasonography

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, August 2011, Thieme Publishing Group

    Stefan Wellek

  42. On easily interpretable multivariate reference regions of rectangular shape

    Article • Biometrical Journal, May 2011, Wiley

    Stefan Wellek

  43. Individualized Correction for Maternal Weight in Calculating the Risk of Chromosomal Abnormalities with First-Trimester Screening Data

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, February 2011, Thieme Publishing Group

    Stefan Wellek

  44. Investigating Hardy–Weinberg equilibrium in case–control or cohort studies or meta-analysis

    Article • Breast Cancer Research and Treatment, December 2010, Springer Science + Business Media

    Stefan Wellek

  45. Association of single nucleotide polymorphisms in ATM, GSTP1, SOD2, TGFB1, XPD and XRCC1 with clinical and cellular radiosensitivity

    Article • Radiotherapy and Oncology, October 2010, Elsevier

    Stefan Wellek

  46. ERRATUM

    Article • Annals of Medicine, August 2010, Taylor & Francis

    Professor Timo Partonen, Stefan Wellek

  47. Testing Statistical Hypotheses of Equivalence and Noninferiority

    Article • June 2010, Taylor & Francis

    Stefan Wellek

  48. Exact linear rank tests for two-sample equivalence problems with continuous data

    Article • Statistica Neerlandica, June 2010, Wiley

    Stefan Wellek

  49. A Confidence-Limit-Based Approach to the Assessment of Hardy-Weinberg Equilibrium

    Article • Biometrical Journal, April 2010, Wiley

    Stefan Wellek

  50. Adapting the logical basis of tests for Hardy-Weinberg Equilibrium to the real needs of association studies in human and medical genetics

    Article • Genetic Epidemiology, November 2009, Wiley

    Stefan Wellek

  51. Searching for Responders to Acamprosate and Naltrexone in Alcoholism Treatment: Rationale and Design of thePredict Study

    Article • Alcoholism Clinical and Experimental Research, March 2009, Wiley

    Stefan Wellek

  52. A Genotype-Based Approach to Assessing the Association between Single Nucleotide Polymorphisms

    Article • Human Heredity, January 2009, Karger Publishers

    Stefan Wellek

  53. A New Approach to Calculating the Risk of Chromosomal Abnormalities with First-Trimester Screening Data

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, December 2008, Thieme Publishing Group

    Stefan Wellek

  54. Systematic Analysis of Glutamatergic Neurotransmission Genes in Alcohol Dependence and Adolescent Risky Drinking Behavior

    Article • Archives of General Psychiatry, July 2008, American Medical Association (AMA)

    Stefan Wellek

  55. Transvaginale Ultraschallbiometrie in der Frühgravidität - Ein Wachstumsmodell

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, May 2008, Thieme Publishing Group

    Stefan Wellek

  56. Das normale fetale Wachstumsprofil - ein einheitliches Modell zur Berechnung von Normkurven für die gängigen Kopf- und Abdomenparameter sowie die großen Extremitätenknochen

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, March 2008, Thieme Publishing Group

    Stefan Wellek

  57. Orbitadurchmesser, innerer und äußerer Orbitaabstand

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, March 2008, Thieme Publishing Group

    Stefan Wellek

  58. Three circadian clock genes Per2, Arntl, and Npas2 contribute to winter depression

    Article • Annals of Medicine, January 2007, Taylor & Francis

    Professor Timo Partonen, Stefan Wellek

  59. Stratification of medulloblastoma on the basis of histopathological grading

    Article • Acta Neuropathologica, April 2006, Springer Science + Business Media

    Stefan Wellek

  60. Zur klinischen Relevanz von Cholinesterase-Inhibitoren bei Alzheimer Krankheit - Eine klinische und biometrische Kritik der AD2000-Studie

    Article • psychoneuro, January 2006, Thieme Publishing Group

    Stefan Wellek

  61. Complete long‐term survival data from a trial of adjuvant chemotherapy vs control after radical cystectomy for locally advanced bladder cancer

    Article • BJU International, December 2005, Wiley

    Stefan Wellek

  62. Genotype-Phenotype Studies in Bipolar Disorder Showing Association Between the DAOA/G30 Locus and Persecutory Delusions: A First Step Toward a Molecular Genetic Classification of Psychiatric Phenotypes

    Article • American Journal of Psychiatry, November 2005, American Psychiatric Association

    Stefan Wellek

  63. Adjuvant Cisplatin Plus Methotrexate Versus Methotrexate, Vinblastine, Epirubicin, and Cisplatin in Locally Advanced Bladder Cancer: Results of a Randomized, Multicenter, Phase III Trial (AUO-AB 05/95)

    Article • Journal of Clinical Oncology, August 2005, American Society of Clinical Oncology (ASCO)

    Stefan Wellek

  64. Statistical Methods for the Analysis of Two‐Arm Non‐inferiority Trials with Binary Outcomes

    Article • Biometrical Journal, February 2005, Wiley

    Stefan Wellek

  65. A new approach to sample size calculation for reference interval studies

    Article • Statistics in Medicine, January 2005, Wiley

    Stefan Wellek

  66. Tests for Establishing Compatibility of an Observed Genotype Distribution with Hardy-Weinberg Equilibrium in the Case of a Biallelic Locus

    Article • Biometrics, August 2004, Wiley

    Stefan Wellek

  67. Statistical confirmation of negative results of association studies in genetic epidemiology

    Article • American Journal of Medical Genetics Part B Neuropsychiatric Genetics, March 2004, Wiley

    Stefan Wellek

  68. Analysis of genetic variations of protein tyrosine kinase fyn and their association with alcohol dependence in two independent cohorts

    Article • Biological Psychiatry, December 2003, Elsevier

    Stefan Wellek

  69. No association of alcohol dependence with a NMDA-receptor 2B gene variant

    Article • Molecular Psychiatry, January 2003, Springer Science + Business Media

    Stefan Wellek

  70. REWARD CRAVING AND WITHDRAWAL RELIEF CRAVING: ASSESSMENT OF DIFFERENT MOTIVATIONAL PATHWAYS TO ALCOHOL INTAKE

    Article • Alcohol and Alcoholism, January 2003, Oxford University Press (OUP)

    Stefan Wellek

  71. Testing Statistical Hypotheses of Equivalence

    Article • November 2002, Taylor & Francis

    Stefan Wellek

  72. Knowledge about Glaucoma in the Unselected Population: A German Survey

    Article • Journal of Glaucoma, October 2002, Wolters Kluwer Health

    Stefan Wellek

  73. The Neuronal Nitric Oxide Synthase Gene Is Critically Involved in Neurobehavioral Effects of Alcohol

    Article • Journal of Neuroscience, October 2002, Society for Neuroscience

    Stefan Wellek

  74. Relationship between Cortisol and Serotonin Metabolites and Transporters in Alcolholism

    Article • Pharmacopsychiatry, July 2002, Thieme Publishing Group

    Stefan Wellek

  75. Blood flow velocity waveforms of the fetal middle cerebral artery in a normal population: reference values from 18 weeks to 42 weeks of gestation

    Article • Journal of Perinatal Medicine, January 2002, De Gruyter

    Stefan Wellek

  76. Age-Related Reference Regions for Longitudinal Measurements of Growth Characteristics

    Article • Methods of Information in Medicine, January 2001, Thieme Publishing Group

    Stefan Wellek

  77. Reference values of fetal aortic flow velocity waveforms and associated intra‐observer reliability in normal pregnancies

    Article • Ultrasound in Obstetrics and Gynecology, January 2001, Wiley

    Stefan Wellek

  78. Age-Related Reference Ranges for Fetal Foot Length

    Article • Ultraschall in der Medizin - European Journal of Ultrasound, December 2000, Thieme Publishing Group

    Stefan Wellek

  79. Bayesian Construction of an Improved Parametric Test for Probability-Based Individual Bioequivalence

    Article • Biometrical Journal, December 2000, Wiley

    Stefan Wellek

  80. Long term follow-up of combined radiochemotherapy for locally advanced bladder carcinoma

    Article • Cancer, September 2000, Wiley

    Stefan Wellek

  81. On a reasonable disaggregate criterion of population bioequivalence admitting of resampling-free testing procedures

    Article • Statistics in Medicine, January 2000, Wiley

    Stefan Wellek

  82. Reference values of ductus venosus flow velocities and calculated waveform indices

    Article • Prenatal Diagnosis, January 2000, Wiley

    Stefan Wellek

  83. A Distribution-Free Two-Sample Equivalence Test Allowing for Tied Observations

    Article • Biometrical Journal, May 1999, Wiley

    Stefan Wellek

  84. Randomised, double blind, multicentre comparison of hydrochlorothiazide, atenolol, nitrendipine, and enalapril in antihypertensive treatment: results of the HANE study

    Article • BMJ, July 1997, BMJ

    Stefan Wellek

  85. A comment on so-called individual criteria of bioequivalence

    Article • Journal of Biopharmaceutical Statistics, January 1997, Taylor & Francis

    Stefan Wellek

  86. Testing for Absence of Qualitative Interactions Between Risk Factors and Treatment Effects

    Article • Biometrical Journal, January 1997, Wiley

    Stefan Wellek

  87. Radical cystectomy with or without adjuvant polychemotherapy for non-organ-confined transitional cell carcinoma of the urinary bladder: Prognostic impact of lymph node involvement

    Article • Urology, December 1996, Elsevier

    Stefan Wellek

  88. A New Approach to Equivalence Assessment in Standard Comparative Bioavailability Trials by Means of the Mann‐Whitney Statistic

    Article • Biometrical Journal, January 1996, Wiley

    Stefan Wellek

  89. Sonographic size of uterus and ovaries in pre‐ and postmenopausal women

    Article • Ultrasound in Obstetrics and Gynecology, January 1996, Wiley

    Stefan Wellek

  90. Age-Related Reference Ranges for Growth Parameters

    Article • Methods of Information in Medicine, September 1995, Thieme Publishing Group

    Stefan Wellek

  91. Prospective randomised trial of chemotherapy given before radiotherapy in childhood medulloblastoma. International society of paediatric oncology (SIOP) and the (German) society of paediatric oncology (GPO): SIOP II

    Article • Medical and Pediatric Oncology, September 1995, Wiley

    Stefan Wellek

  92. Sonographische Normkurven des fetalen knöchernen Thorax und der fetalen Lunge

    Article • Geburtshilfe und Frauenheilkunde, February 1995, Thieme Publishing Group

    Stefan Wellek

  93. Adjuvant Polychemotherapy of Nonorgan-Confined Bladder Cancer After Radical Cystectomy Revisited: Long-Term Results of a Controlled Prospective Study and Further Clinical Experience

    Article • The Journal of Urology, January 1995, Wolters Kluwer Health

    Stefan Wellek

  94. Factors influencing survival after resection of pancreatic cancer. A DNA analysis and a histomorphologic study

    Article • Cancer, January 1994, Wiley

    Stefan Wellek

  95. Prognostic value of DNA analysis in colorectal carcinoma

    Article • Cancer, December 1993, Wiley

    Stefan Wellek

  96. A Log-Rank Test for Equivalence of Two Survivor Functions

    Article • Biometrics, September 1993, JSTOR

    Stefan Wellek

  97. Basing the Analysis of Comparative Bioavailability Trials on an Individualized Statistical Definition of Equivalence

    Article • Biometrical Journal, January 1993, Wiley

    Stefan Wellek

  98. DNA image cytometry in stomach carcinoma. Its relation to histomorphologic parameters and its influence on prognosis

    Article • Cancer, October 1992, Wiley

    Stefan Wellek

  99. Advanced Bladder Cancer (Stages pT3b, pT4a, pN1 and pN2): Improved Survival after Radical Cystectomy and 3 Adjuvant Cycles of Chemotherapy. Results of a Controlled Prospective Study

    Article • The Journal of Urology, August 1992, Wolters Kluwer Health

    Stefan Wellek

  100. Vergleich der DNS-Analyse mit histomorphologischen parametern beim Magenkarzinom

    Article • Langenbecks Archiv für Chirurgie, January 1992, Springer Science + Business Media

    Stefan Wellek

  101. Diagnosis, Therapeutic Strategy and Prognosis of Acute Mesenteric Vascular Occlusion: Results of a Consecutive Series

    Article • Digestive Surgery, January 1992, Karger Publishers

    Stefan Wellek

  102. Fortgeschrittenes Blasenkarzinom (Stadien pT3b, pT4a, pN1, pN2)

    Article • Aktuelle Urologie, July 1991, Thieme Publishing Group

    Stefan Wellek

  103. Elements of Significance Testing with Equivalence Problems

    Article • Methods of Information in Medicine, January 1991, Thieme Publishing Group

    Stefan Wellek

  104. Hydrochlorothiazide and Verapamil in the Treatment of Hypertension

    Article • Journal of Cardiovascular Pharmacology, January 1991, Wolters Kluwer Health

    Stefan Wellek

  105. Hemodynamics During PEEP Ventilation in Patients with Severe Left Ventricular Failure Studied by Transesophageal Echocardiography

    Article • CHEST Journal, May 1990, Elsevier

    Stefan Wellek

  106. Reference Standards for Software Evaluation

    Article • Methods of Information in Medicine, January 1990, Thieme Publishing Group

    Stefan Wellek

  107. On the use of asymptotic expansion in computing the null distribution of page's L-statistic

    Article • Communications in Statistics - Simulation and Computation, January 1989, Taylor & Francis

    Stefan Wellek

  108. Die Medulloblastom-Therapiestudien MBL 80* und MED 84** der Gesellschaft für Pädiatrische Onkologie (GPO) und der Société Internationale d'Oncologie Pédiatrique (SIOP)

    Article • Klinische Pädiatrie, May 1987, Thieme Publishing Group

    Stefan Wellek