Skip to main content
SpringerLink
Log in

Re-treatment Studies: Design and Analysis

  • Statistics
  • Published:
Drug information journal : DIJ / Drug Information Association Aims and scope Submit manuscript

Abstract

For some disorders such as irritable bowel syndrome, symptoms may wax and wane with variable periodicity. In clinical practice, treatment is usually targeted at symptom reduction during exacerbations. The management of such patients will likely involve intermittent courses of therapy tailored to the patient’s individual symptom pattern instead of chronic, uninterrupted treatment. Three study designs to assess the feasibility and efficacy of repeated drug treatment in patients with irritable bowel syndrome are discussed. The first design is a parallel group design in which patients, after the initial treatment period, may repeatedly receive the same treatment as in the first period (test drug or control). In the second design, patients who respond favorably to initial treatment with a test drug and whose symptoms recur when this treatment is stopped will be randomly assigned to receive the test drug or control in a second period. The third design has in addition a control group in the initial period. The three designs are compared regarding analysis and sample size.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Temple RJ. Special study design, early escape, enrichment, studies in non-responders. Commun StatTheory Methods. 1994;23:499–531.

    Article  Google Scholar 

  2. Camilleri M. Management of the irritable bowel syndrome. Gastroenterology. 2001;120:652–668.

    Article  CAS  Google Scholar 

  3. Schuster MM. Defining and diagnosing irritable bowel syndrome. Am J Manag Care. 2001;7(8, suppl.):S246–S251.

    CAS  PubMed  Google Scholar 

  4. Thompson WG, Longstreth GF, Drossman DA, et al. Functional bowel disorders and functional abdominal pain. Gut. 1999;45(suppl. 2):43–47.

  5. Horwitz BJ, Fisher RS. The irritable bowel syndrome. N Engl J Med. 2001;344:1846–1850.

    Article  CAS  Google Scholar 

  6. Hahn B, Watson M, Yan S, et al. Irritable bowel syndrome symptom patterns. Dig Dis Sci. 1998;43:2715–2718.

    Article  CAS  Google Scholar 

  7. Mearin, Baro E, Roset M, et al. Clinical patterns over time in irritable bowel syndrome: symptom instability and severity variability. Am J Gastroenterot. 2004;99:113–121.

    Article  Google Scholar 

  8. Ragnarsson G, Bodemar G. Pain is temporally related to eating but not to defection in the irritable bowel syndrome. Eur J Gastroenterol Hepatol. 1998;10:415–421.

    Article  CAS  Google Scholar 

  9. Stevens JA, Wan CK, Blanchard EB. The short natural history of irritable bowel syndrome: a time series analysis. Behav Res Ther. 1997;35:319–326.

    Article  CAS  Google Scholar 

  10. The European Agency for Evaluation of Medicinal Products. Committee for Proprietary Medicinal Products. Points to consider on the evaluation of medicinal products for the treatment of irritable bowel syndrome. CPMP/EWP/785/97. April 2002.

  11. Drossman DA, et al. Appendix B. The Rome II Modular Questionnaire. In: Drossman DA, Coraz-ziari E, Talley NJ, Thompson WG, Whitehead WE, eds. Rome II: The Functional Gastrointestinal Disorders. McLean, Degnon; 2000:670–688.

  12. Mülier-Lissner S, et al. Subject’s global assessment of relief: an appropriate method to assess the impact of treatment on irritable bowel syndrome-related symptoms in clinical trials. J Clin Epidemiol. 2003;56:310–316.

    Article  Google Scholar 

  13. ICH E9 Expert Working Group. ICH harmonised tripartite guideline: statistical principles for clinical trials. Stat Med. 1999;18:1905–1942.

    Google Scholar 

  14. Veldhuyzen van Zanten SJO, Talley N, Bytzer P, et al. Design of treatment trials of functional gastrointestinal disorders. Gut. 1999;45(suppl 2): 1169–1177.

  15. Maurer W, Hothorn L, Lehmacher W. Multiple comparisons in drug clinical trials and preclinical assays: a-priori ordered hypotheses. In Vollmar J, ed. Biometrie in der chemisch-phar-mazeutischen Industrie. Gustav Fischer Verlag;1995:3–18

  16. Hochberg Y. A sharper Bonferroni procedure for multiple tests of significance. Biometrika. 1988;75:800–802.

    Article  Google Scholar 

  17. Westfall PH, Tobias RD, Wolfinger RD, Hochberg Y. Multiple Tests Using the SAS System. Cary, NC: SAS Institute; 1999.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Novartis Pharma AG, Lichtstrasse 35, CH-4002, Basel, Switzerland

    Cornelia Dunger-Baldauf PhD & Amy Racine PhD

  2. Department of Biostatistics, University of North Carolina, Chapel Hill, USA

    Gary Koch PhD

Authors
  1. Cornelia Dunger-Baldauf PhD
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Amy Racine PhD
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Gary Koch PhD
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Cornelia Dunger-Baldauf PhD.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Dunger-Baldauf, C., Racine, A. & Koch, G. Re-treatment Studies: Design and Analysis. Ther Innov Regul Sci 40, 209–217 (2006). https://doi.org/10.1177/009286150604000210

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1177/009286150604000210

Key Words

Search

Navigation