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Withdrawn No phase listed Observational Accepts healthy volunteers

Optimization of Collection Methods for Studies of the Human Microbiota

ClinicalTrials.gov ID: NCT03731702

Public ClinicalTrials.gov record NCT03731702. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 5, 2026, 9:10 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

Background: The human microbiota is the bacteria and other microbes found in and on the human body. Scientists study the microbiota because it is related to many health conditions. The way samples are collected and handled can greatly affect microbiota study findings. Researchers want to learn more about how collection methods affect these studies. Objectives: To compare different oral and fecal collection methods. To test the effect of new methods to get DNA out of these samples. Eligibility: Adults ages 18 and older who are National Cancer Institute employees and have not taken antibiotics in the past 3 months Design: Participants will discuss the study with researchers. Participants will give an oral or fecal sample or both. For the oral sample, participants will be told what not to do beforehand. This includes chewing gum and smoking. Participants will spit saliva into a tube. Then they will get mouthwash in a vial. They will swish and gargle the mouthwash for 30 seconds then spit it back in the vial. Participants giving a fecal sample will get a collection kit. They can collect the sample at home or elsewhere. Participants will have a bowel movement into the collection container. They will smear some of it on a card with a stick and put the rest in 2 tubes. They will mix the feces with the solution in the tubes. Participants will write the date and time of collection on the instructions and return the sample within 24 hours. Participants providing both samples could have 3 study visits: 1 to give an oral sample, 1 to get the fecal sample collection kit, and 1 to return that sample.

Study identification

NCT ID
NCT03731702
Recruitment status
Withdrawn
Study type
Observational
Phase
Not listed
Enrollment
Not listed

Conditions and interventions

Interventions

Not listed

Eligibility (public fields only)

Age range
18 Years to 100 Years
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 31, 2018
Primary completion
Oct 26, 2020
Completion
Oct 26, 2020
Last update posted
Oct 27, 2020

2018 – 2020

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
NIH NCI Shady Grove Rockville Maryland 20850

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT03731702, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Oct 27, 2020 · Synced Sep 5, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT03731702 live on ClinicalTrials.gov.

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