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The PRIDE Study Probiotics on Regulation and Improving Digestive hEalth (PRIDE)

This study has been completed.
Information provided by (Responsible Party):
Georgetown University Identifier:
First received: September 15, 2010
Last updated: February 8, 2013
Last verified: December 2012
The purpose of this study is to determine the effect of probiotic supplemented yogurt in reducing colonic transit time (CTT) in females between the ages of 18-65 years old. Two yogurts will be administered, one containing a specific strain of probiotic in the Bifidobacterium genus and the other without the probiotic supplement. It is hypothesized that subjects receiving the probiotic supplemented yogurt will experience reduced CTT and improved gastrointestinal comfort and quality of life compared to those receiving the non-probiotic supplemented yogurt.

Condition Intervention Phase
Digestive Irregularity Digestive Discomfort History of Straining During Bowel Movements History of Hard or Lumpy Stools Other: Probiotic strain of Bifidobacterium Other: No Bifidobacterium Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Probiotic Double-blind Randomized Placebo Crossover Trial of Colonic Transit Time in Adult Females, The PRIDE Study The Study to Determine the Effects of Probiotics on Regulation and Improving Digestive hEalth

Further study details as provided by Georgetown University:

Primary Outcome Measures:
  • Colonic Transit Time [ Time Frame: 90 days ]

Secondary Outcome Measures:
  • Frequency of bowel movements (daily) [ Time Frame: 90 days ]
  • Stool consistency (daily) [ Time Frame: 90 days ]
  • Well being as assessed by agreed upon quality of life instrument [ Time Frame: 90 days ]
  • Dietary intake survey [ Time Frame: 90 days ]
  • Tolerance [ Time Frame: 90 days ]
    by questionnaire: e.g. bloating

  • Rome criteria [ Time Frame: 90 days ]
  • Bristol criteria [ Time Frame: 90 days ]
  • Recovery of the probiotic in the faeces (quantitative measure) [ Time Frame: 90 days ]
  • Bacterial composition of the fecal flora [ Time Frame: 90 days ]
  • Adverse events [ Time Frame: 90 days ]

Enrollment: 68
Study Start Date: October 2010
Study Completion Date: July 2011
Primary Completion Date: July 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Bifidobacterium supplemented yogurt
Bifidobacterium supplemented (minimum dosage of 1E+10cfu/serving) vanilla flavored yogurt containing starter cultures: Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus
Other: Probiotic strain of Bifidobacterium
4 ounces (113g) of yogurt per day, for 14 days. Minimum Bifidobacterium dose of 1E+10 cfu/serving.
Placebo Comparator: Placebo Yogurt
Vanilla flavored yogurt containing starter cultures Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus
Other: No Bifidobacterium
4 ounces (113g) of yogurt per day, for 14 days. No bifidobacterium added.


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Being female
  • Ability to speak and write English or Spanish
  • Willingness to refrain from specified probiotic supplements, during the 12 week trial (a list of prohibited products will be provided)
  • Have access to refrigeration and phone
  • Have a history of straining during bowel movements
  • Have a history of lumpy or hard stools

Exclusion Criteria:

  • Presence of an allergy or intolerance to any ingredients in yogurt
  • Morbid obesity, defined as a BMI>40
  • Having inflammatory bowel disease
  • Having a history of malabsorption syndrome
  • Immunodeficiency, such as HIV or currently receiving chemotherapy
  • Consumption of any medications used to treat, prevent or cure diarrhea in the last month
  • Consumption of any medications used to treat, prevent or cure constipation in the last month
  • Diabetes mellitus
  • Thyroid disorders, including hypo- or hyperthyroidism
  • History of gastric, small bowel or colonic resection
  • Documented history of gastric emptying disorder
  • Consumption of narcotics, antipsychotic medications, or verapamil in the last month
  • Known pelvic outlet obstruction
  • Antibiotic usage within 4 weeks of enrollment
  • Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01203462

United States, District of Columbia
Georgetown University Department of Family Medicine, Research Division
Washington, District of Columbia, United States, 20007
Sponsors and Collaborators
Georgetown University
Principal Investigator: Dan Merenstein, MD Georgetown University
Principal Investigator: Caren Palese, MD Georgetown University
  More Information

Responsible Party: Georgetown University Identifier: NCT01203462     History of Changes
Other Study ID Numbers: 2010-402
Study First Received: September 15, 2010
Last Updated: February 8, 2013 processed this record on September 21, 2017