Clinical Skills · Specimen Collection and Lab Testing

Stool Collection

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On this page 9 sections

In 30 seconds
Why this matters
The college version
Eli explains
Worked example
Key takeaway
Check yourself
Study tools
Sources & references

In 30 seconds

A stool specimen is a sample of a person's bowel movement (feces) collected for laboratory testing. Stool tests look at what is happening in the digestive tract: hidden bleeding, infections, parasites, inflammation, and problems with digestion and absorption. Stool collection follows the same core principles as urine collection — avoid contamination, label correctly, transport promptly — plus a few of its own: stool is often collected from a bedpan or collection device, some tests require the sample to reach the lab quickly, and some require more than one sample.

This topic follows urine specimen collection in the chapter and shares its logic: the laboratory result is only as good as the sample. Because stool collection can be embarrassing and physically awkward, the nurse's communication, privacy, and dignity practices matter as much as the technique.

Why this matters

Stool tests answer important clinical questions:

Hidden (occult) blood — screening for bleeding in the digestive tract, including colorectal cancer screening.
Infection — testing for bacteria such as , a common and serious cause of diarrhea in health care settings.
Parasites — testing for when a parasitic infection is suspected.
Inflammation and malabsorption — markers such as fecal calprotectin, and tests for fat in the stool, help evaluate inflammatory bowel conditions and absorption problems.

A stool sample contaminated by toilet water or urine can ruin the test: water dilutes the sample, and urine can interfere with detection. For infectious-disease testing, a contaminated or stale sample can produce a false negative that delays treatment — and for a person with C. diff, that delay can mean the infection spreads to others. Collecting stool correctly is also an infection-prevention skill, because stool can carry organisms that spread easily.

The college version

Core Concepts

What stool tests look for

Fecal occult blood tests (FOBT/FIT) detect blood that is not visible to the eye — used for colorectal cancer screening. Different tests have different preparation instructions (for example, some ask the person to avoid certain foods or medications beforehand); always follow the specific test's instructions.
Stool culture grows bacteria to identify an infection.
C. difficile testing looks for the toxin (or the toxin gene) in the stool of a person with diarrhea. The toxin breaks down quickly, so the sample must reach the lab promptly.
Ova and parasites (O&P) testing looks for parasite eggs and organisms. Some tests require the sample to be fresh, others need a , and some collections span multiple days — follow the laboratory's instructions.
Quantitative tests (such as fecal fat) measure amounts over time, and preparation instructions may apply.

Collection methods

Bedpan or commode "hat": the person uses a clean bedpan, or a collection "hat" placed in the toilet seat (not in the water). The nurse transfers a portion of stool into the specimen container with the provided spatula.
Collection device over the toilet: a plastic device or disposable liner sits inside the bowl so stool lands out of the water.
For infants and young children: stool is collected from a clean diaper with a spatula as soon as possible, avoiding urine.
Never scoop stool out of toilet water, never let urine or toilet paper mix with the sample, and never leave a sample at room temperature for hours.

The collection procedure

Verify the order and the person's identity; explain what is needed and how the person should let staff know when they are ready.
Perform hand hygiene and apply gloves (plus any additional personal protective equipment required by the person's isolation status).
Assist the person onto a bedpan or commode with the collection device, provide privacy, and place the call light within reach.
After the person finishes, transfer a portion of stool into the container using the provided spatula — the amount is specified by the test and the container.
Cap the container securely, and label it at the bedside with two patient identifiers, the date and time, and the type of test.
Clean the bedpan and area per facility protocol; remove gloves and perform hand hygiene.
Transport the specimen per laboratory policy — some tests need immediate delivery, some need refrigeration, some have preservatives in the container.
Document the collection, and note observations about the stool itself (color, consistency, frequency) — these are clinically useful.

Special considerations

C. difficile and isolation: the person may be on — gown and gloves, dedicated or cleaned equipment, and meticulous hand hygiene (washing with soap and water is often emphasized for C. diff, per facility policy). Collection technique is the same, but timing matters: the sample should reach the lab quickly because the toxin degrades.
Multiple samples: some tests (for example, O&P in certain situations) require samples on different days. Teach the person and keep a collection schedule.
Contrast material: recent imaging studies using contrast can interfere with some stool tests — note this when collecting and follow timing instructions.
Medications and diet: some tests have preparation instructions (such as avoiding certain foods or medications beforehand). Do not assume — check the specific test's instructions.
Labeling and transport follow the same rules as all specimens: label at the bedside, transport promptly, and handle special tests per the laboratory's requirements.

Common Confusions

Do Not Confuse	With	The Difference
Stool collection	Urine collection	Different containers and tests — and urine mixed into a stool sample contaminates it
"Any sample will do"	"Test-specific requirements"	Some tests need fresh samples, some need preservatives, some need multiple samples over days
Collecting from the toilet	Collecting from a hat or device	Toilet water destroys the sample; stool must land out of the water
C. diff testing	Routine stool culture	Different tests; C. diff needs a fresh sample and contact precautions
Specimen left at the bedside	Prompt transport	Toxins and other analytes degrade at room temperature; deliver per lab policy
Gloves only	Full PPE per isolation status	Follow the person's isolation status — C. diff requires gown and gloves, plus hand hygiene per policy

Eli explains

The same idea, in plain words

Explain it like I’m 10

Testing poop helps doctors find problems in the digestive system, like hidden blood, infections, or parasites. The nurse collects a little bit into a clean cup without letting toilet water or pee touch it, because those would ruin the test. The cup is labeled with the person's name and rushed to the lab, because some tests only work with fresh samples.

Worked example

Mr. D., age 71, is on a medical unit with three days of watery diarrhea after antibiotics. The provider orders C. difficile testing, and because C. diff is suspected, Mr. D. is on contact precautions.

The nurse explains the collection, gives Mr. D. a commode hat placed in the toilet seat, and tells him to press the call light when he is ready — not to flush. When the light comes on, the nurse dons gloves and gown, enters, and provides privacy. After Mr. D. finishes, the nurse transfers a portion of stool into the container with the spatula, caps it, and labels it at the bedside with Mr. D.'s name, date of birth, date, time, and "C. diff." The nurse cleans the commode hat per protocol, removes the PPE, and performs hand hygiene. Because the toxin degrades quickly, the nurse calls the lab and transports the specimen promptly, and documents the collection, noting the stool's watery character.

If the sample had instead been scooped from the toilet bowl and left on the bedside table for the evening shift, the test could easily have come back falsely negative — Mr. D.'s infection could have gone untreated while the risk to other patients grew.

Key takeaways

Never let toilet water, urine, or toilet paper touch the sample.
Use a clean bedpan, commode hat, or toilet collection device; transfer stool with the provided spatula.
Label at the bedside with two patient identifiers, date, time, and the test type.
Follow test-specific requirements: preparation instructions, multiple samples, fresh vs. preserved, transport timing.
Transport promptly — C. diff toxin and other analytes break down at room temperature.
Use gloves always, plus PPE per isolation status (contact precautions for C. diff); hand hygiene after.
Document stool characteristics and the collection itself.
Teach the person to call staff before using the bathroom so the sample is not flushed.
Protect privacy and dignity — explain, cover, and be matter-of-fact.

Check yourself

6 review questions from the chapter. Try each one, then open the answer.

Name two common sources of stool sample contamination.
Show answer
Toilet water, urine, toilet paper, an unclean collection device, or handling with ungloved hands (any two).
Why must some stool samples reach the lab quickly?
Show answer
Some analytes and organisms degrade at room temperature — for example, the C. diff toxin — so a delayed sample can give a false negative.
What PPE and hygiene steps apply when collecting stool from a person on contact precautions?
Show answer
Gloves and gown (contact precautions), meticulous technique to avoid contaminating the environment, and hand hygiene after removal; follow the facility's policy (which often emphasizes washing with soap and water for C. diff).
What should the nurse tell a person to do instead of flushing when a specimen is ordered?
Show answer
Call staff before using the bathroom so the nurse can collect the sample — do not flush until the specimen is obtained.
Name three things stool tests can detect.
Show answer
Hidden (occult) blood, bacterial infections such as C. diff, parasites (ova and parasites), inflammation markers, and fat/malabsorption problems (any three).
What information goes on the specimen label?
Show answer
Two patient identifiers, the date and time of collection, and the type of test — labeled at the bedside.

Keep learning

Ready to build on this? Continue to the next lesson.

Study tools & related lessonsKey vocabulary · Related

Key vocabulary

Stool (feces) specimen: A sample of bowel movement collected for laboratory testing
Fecal occult blood test (FOBT/FIT): A test that detects hidden blood in stool
Ova and parasites (O&P): Testing for parasite eggs and organisms
Clostridioides difficile (C. diff): A bacterium that causes antibiotic-associated diarrhea; detected by stool toxin testing
Commode hat: A collection device that sits in a toilet seat to catch stool out of the water
Spatula (applicator): The tool used to transfer stool into the specimen container
Preservative: A chemical in some containers that keeps organisms or substances stable
Contact precautions: Gown-and-glove protection for infections spread by direct contact

Sources & references

openstax.org — Clinical Nursing Skills

This lesson was adapted from the open educational references above; their licenses and attributions are preserved. See Copyright & Licensing.

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