• Irritable Bowel Syndrome Evaluation and Treatment in Primary Care Pilot Project

    Study Description and Methods

    Diagnosing IBS is a known clinical challenge. IBS is considered a “diagnosis of exclusion” and therefore the diagnosis is often made after extensive testing has been undertaken. The average time from the onset of symptoms to a positive diagnosis of IBS is nearly 3 years.

    The AAFP NRN investigative team has developed a protocol for a pilot project using the Genova Diagnostics (GDx) tests. Individuals with IBS are known to have a 20% to 40% placebo response rate when all individuals with the diagnosis are included in studies. Whether this high placebo response rate is maintained over a longer period of treatment (e.g., 16 weeks) or whether this is true for the subset of individuals with positive stool tests is not well understood. Before initiating a large scale study of the effectiveness of therapy guided by the GDx tests, it is critical to evaluate the placebo response issue, as well as approaches to patient recruitment, study work flow in primary care offices, and selected outcome measures. The AAFP NRN believes this overall research direction could lead to widespread changes in care for individuals with IBS and substantially improve care within primary care offices.

    Specific Aims and Objectives

    1. Evaluate how well Genova Diagnostics (GDx) IBS tests can be integrated into primary care,
    2. Examine the effects of the Genova Diagnostics (GDx) test on treatment, and
    3. Observe and track patients’ health, quality of life, and clinical outcomes related to IBS during the study period.


    This project was conducted from September 2010 through October 2011.


    Data collection has closed for this project. Information collected will be used to develop an additional research project.

    Contact Information

    For additional information about this study, please contact:

    Brian Manning, MPH, CHES
    Associate Research Director
    AAFP National Research Network
    1-800-274-2237, x3179

    This project was funded by an unrestricted grant from Genova Diagnostics (GDx) and Proctor and Gamble, Inc.