Todd A. Alonzo, Ph.D.

Professor of Research

Department of Preventive Medicine
University of Southern California
Children' s Oncology Group
440 E. Huntington Dr, 4th floor
Arcadia, CA 91006
Phone: (626) 241-1522
Fax: (626) 445-4334

E-Mail: talonzo@childrensoncologygroup.org

Education

Research Interests

Statistical methods for the analysis of medical diagnostic and screening test data

New methods of disease detection (e.g., biomarkers, genetic markers, and imaging modalities) are being developed rapidly. Their accuracy must be evaluated before they are implemented in practice. Dr. Alonzo's research involves developing methods that allow unbiased assessment of accuracy (sensitivity, specificity, ROC curve) in practical settings. One such setting is where there is incomplete disease ascertainment because ascertainment of disease status may be too invasive or costly to be done in all study subjects. Although it may be more ethical or cost-effective to ascertain true disease status in those who appear to be at higher risk, estimates of disease prevalence and test accuracy can be biased in a study with such a design. Dr. Alonzo has developed methods that allow unbiased estimation of accuracy when their is incomplete disease ascertainment.

Design and analysis of pediatric acute myeloid leukemia (AML) studies

Dr. Alonzo is the statistician for the Acute Myelogenous Leukemia (AML) Committee of the Children's Oncology Group. He is responsible for design and analysis of phase I, II, and III studies of children with AML, as well as correlative biology studies.

CV

Selected Publications

Statistical methods for the analysis of medical diagnostic and screening test data

  1. Alonzo TA, Pepe MS. Using a combination of reference tests to assess the accuracy of a new diagnostic test. Statistics in Medicine 18: 2987-3003, 1999. pdf version


  2. Leisenring W, Alonzo T, Pepe MS. Comparisons of predictive values of binary medical diagnostic tests for paired designs. Biometrics 56: 345-351, 2000.


  3. Pepe MS, Alonzo TA. Comparing disease screening tests when true disease status is ascertained only for screen positives. Biostatistics 2: 249-260, 2001. pdf version


  4. Alonzo TA, Pepe MS, Moskowitz CS Design of studies to compare accuracy of tests for detecting presence of disease. Statistics in Medicine 21: 835-852, 2002. pdf version


  5. Alonzo TA, Pepe MS. Distribution-free ROC analysis using binary regression techniques. Biostatistics 3: 421-432, 2002. pdf version

  6. Alonzo TA, Pepe MS, Lumley TS. Estimating disease prevalence in two-phase studies. Biostatistics 4: 313-326, 2003. pdf version
     
  7. Alonzo TA, Braun TB, Moskowitz CS. Small sample estimation of relative accuracy for binary screening tests. Statistics in Medicine 23: 21-34, 2004. pdf version
     
  8. Alonzo TA, Pepe MS. Assessing accuracy of a continuous screening test in the presence of verification bias. Journal of the Royal Statistical Society: Series C (Applied Statistics) 54: 173-190, 2005. pdf version
     
  9. Alonzo TA. Verification bias-corrected estimators of the relative true and false positive rates of two binary screening tests. Statistics in Medicine 24:403-417, 2005. pdf version 

  10. Alonzo TA. Standards for Reporting Prognostic Tumor Marker Studies. Journal of Clinical Oncology 23:9053-9054, 2005. pdf version

  11. Brumback LC, Pepe MS, Alonzo TA. Using the ROC curve for gauging treatment effect in clinical trials. Statistics in Medicine 25:575-590, 2006.

  12. Alonzo TA, Kittelson JC. A novel design for estimating relative accuracy of screening tests when complete disease verification is not feasible. Biometrics 62:605-612, 2006. pdf version

  13. Nakas CT, Alonzo TA. ROC graphs for assessing the ability of a diagnostic marker to detect three disease classes with an umbrella ordering. Biometrics 63:603-609, 2007. pdf version

  14. Alonzo TA, Siegmund KA. Statistical methods for evaluating DNA methylation as a marker for early detection or prognosis. Disease Markers 23: 113-120, 2007.

  15. Alonzo TA, Nakas CT. Comparison of ROC umbrella volumes with an application to the assessment of lung cancer diagnostic markers. Biometrical Journal 49: 654-664, 2007.

  16. Alonzo TA, Pepe MS. Development and evaluation of classifiers. Methods in Molecular Biology. 404:89-116, 2007.

  17. Braun TM, Alonzo TA. A modified sign test for comparing paired ROC curves. Biostatistics 9:364-372, 2008.

  18. Shaw PA, Pepe MS, Etzioni R, Alonzo TA, Lehman CD. Evaluating diagnostic accuracy of a combination test when disease status is verified only on positive screenees. Statistics in Biopharmaceutical Research 1: 18-25, 2009.
     

  19. Alonzo TA, Nakas CT, Yiannoutsos CT, Butcher S. A comparison of tests for restricted orderings in the three-class case Statistics in Medicine 28: 1144-1158, 2009.
     

  20. Glueck DH, Lamb MM, O’Donnell CI, Ringham BM, Brinton JT, Muller KE, Lewin JM, Alonzo TA, Pisano ED. Bias in trials comparing paired continuous tests can cause researchers to choose the wrong screening modality BMC medical research methodology 9:4, 2009.
     

  21. Alonzo TA. Comparing accuracy in an unpaired post-market device study with incomplete disease assessment Biometrical Journal 51: 491-503, 2009.
     

  22. Alonzo TA, Nakas CT, Papadopoulos NT, Papachristos DP. A Receiver Operating Characteristic analysis approach for the assessment of the separation of female Mediterranean Fruit fly (Diptera: Tephritidae) oviposition distributions Journal of Economic Entomology 102: 1985-1991, 2009.
     

  23. Ringham BM, Alonzo TA, Grunwald GK, Glueck DH. Estimates of observed sensitivity and specificity must be corrected when reporting the results of the second test in a screening trial conducted in series BMC medical research methodology 10:3, 2010.
     

  24. Nakas CT, Alonzo TA, Yiannoutsos CT. Accuracy and cut-off point selection in three-class classification problems Statistics in Medicine (In Press)


Design and analysis of pediatric acute myeloid leukemia (AML) studies

  1. Alonzo TA, Kobrinksy NL, Aledo A, Lange BJ, Buxton AB, Woods WG. Impact of granulocyte colony-stimulating factor use during induction for Acute Myelogenous Leukemia in Children: A report from the Children’s Cancer Group. Journal of Pediatric Hematology/Oncology 24: 627-635, 2002. pdf version

  2. Woods WG, Barnard DR, Alonzo TA, Buckley JD, Howells WB, Kobrinsky N, Arthur DC, Sanders J, Neudorf S, Gold S, Lange BJ. Prospective study of 90 children requiring treatment for juvenile myelomonocytic leukemia or myelodysplastic syndrome: a report from the Childrens Cancer Group. Journal of Clinical Oncology 20: 434-440, 2002. pdf version


  3. Wells RJ, Arthur DC, Srivastava A, Heerema NA, Le Beau M, Alonzo TA, Buxton AB, Woods WG, Howells WB, Benjamin DR, Betcher DL, Buckley JD, Feig SA, Kim T, Odom LF, Ruymann FB, Smithson WA, Tannous R, Whitt JK, Wolff L, Tjoa T, Lampkin BC. Prognostic variables in newly diagnosed children and adolescents with acute myeloid leukemia: Childrens Cancer Group Study 213. Leukemia 16: 601-607, 2002. pdf version


  4. Barnard DR, Lange B, Alonzo TA, Buckley J, Kobrinsky N, Gold S, Neudorf S, Sanders J, Burden L, Woods WG. Acute Myeloid Leukemia and Myelodysplastic Syndrome in Children Treated for Cancer: Comparison with Primary Presentation. Blood 100: 427-434, 2002. pdf version

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  5. Sievers EL, Lange BJ, Alonzo TA, Gerbing RB, Bernstein ID, Smith FO, Arceci RJ, Woods WG, Loken MR. Immunophenotypic evidence of leukemia after induction therapy predicts relapse: results from a prospective Children’s Cancer Group study of 252 patients with acute myeloid leukemia. Blood 101: 3398-3406, 2003. pdf version
     
  6. Casillas J, Woods WG, Hunger SP, McGavran L, Alonzo TA, Feig SA. Prognostic implications of a t(10;11) translocation in childhood acute myelogenous leukemia (AML): a report from the Children’s Cancer Group. Journal of Pediatric Hematology/Oncology 25: 594-600, 2003. pdf version
     
  7. Meshinchi S, Stirewalt DL, Alonzo TA, Zhang Q, Sweetser DA, Larsen S, Woods WG, Bernstein ID, Arceci RJ, Radich JP. Activating mutations of RTK/ras signal transduction pathway in pediatric acute myeloid leukemia. Blood 102: 1474-1479, 2003. pdf version
     
  8. Wells RJ, Adams MT, Alonzo TA, Arceci RJ, Buckley J, Buxton AB, Dusenberry K, Gamis A, Masterson M, McGavran L, Vik T, Warkentin P, Whitlock J. Mitoxantrone and Cytarabine Induction, High Dose Cytarabine and Etoposide Intensification for Pediatric Patients with Relapsed or Refractory Acute Myeloid Leukemia: Children’s Cancer Group Study 2951. Journal of Clinical Oncology 21: 2940-2947, 2003.  pdf version
     
  9. Gamis AS, Woods WG, Alonzo TA, Buxton AB, Lange B, Barnard DR, Gold S, Smith FO. Increased age at diagnosis has a significantly negative effect on outcome in children with Down Syndrome and acute myeloid leukemia: a report from the Children’s Cancer Group Study 2891. Journal of Clinical Oncology 21: 3415-3422, 2003. pdf version
     
  10. Lange BJ, Dinndorf P, Smith FO, Arndt C, Barnard D, Feig S, Feusner J, Seibel N, Weiman M, Aplenc R, Gerbing R, Alonzo TA. Pilot study of Idarubicin-based intensive timing induction therapy for children with previously untreated Acute Myeloid Leukemia: Children’s Cancer Group Study 2941. Journal of Clinical Oncology 22: 150-156, 2004. pdf version
     
  11. Lange BJ, Gerbing RB, Feusner J, Skolnik J, Sacks N, Smith FO, Alonzo TA. Mortality in overweight and underweight children with Acute Myeloid Leukemia. JAMA 293: 203-211, 2005. pdf version
     
  12. Alonzo TA, Wells R, Woods WG, Lange B, Gerbing RB, Neudorf S, Sanders J, Smith FO, Feig SA. Post-Remission Therapy for Childhood Acute Myeloid Leukemia. The Children’s Cancer Group Experience in the Transplant Era. Leukemia 19:965-970, 2005. pdf version
     
  13. Meshinchi S, Stirewalt DL, Alonzo TA, Gerbing RB, Lange BJ, Gilliland DG, Radich JP. Structural and numerical variation of FLT3/ITD in pediatric AML - a report from the Children's Oncology Group. Blood 111:4930-4933, 2008.
     
  14. Pollard JA, Alonzo T, Gerbing RB, Ho P, Zeng R, Ravindranath Y, Dahl G, Lacayo N, Becton D, Chang MN, Weinstein HJ, Hirsch B, Raimondi SC, Heerema NA, Woods W, Lange B, Hurwitz C, Arceci RJ, Radich JP, Bernstein ID, Heinrich M, Meshinchi S. Prevalence and prognostic significance of KIT mutations in pediatric core binding factor AML patients enrolled on serial pediatric cooperative trials for de novo AML Blood 115: 2372-2379, 2010.
     
  15. Walter RB, Alonzo TA, Gerbing RB, Ho PA, Smith FO, Raimondi SC, Hirsch BA, Gamis AS, Franklin JL, Hurwitz CA, Loken MR, Meshinchi S. High Expression of the Very Late Antigen (VLA)-4 Integrin Independently Predicts Reduced Risk of Relapse and Improved Outcome in Pediatric Acute Myeloid Leukemia: A Report From the Children’s Oncology Group Journal of Clinical Oncology 28: 2831-2838, 2010.
     
  16. Ho P, Zeng R, Alonzo TA, Gerbing RB, Miller K, Pollard JA, Stirewalt DL, Hereema NA, Raimondi SC, Hirsch BA, Franklin J, Lange B, Meshinchi S. Prevalence and prognostic implications of WT1 mutations in pediatric acute myeloid leukemia (AML): a report from the Children's Oncology Group Blood 116: 702-710, 2010.
     

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Last modified: August 31, 2010