Not every blood specimen is collected the same way. While many laboratory tests follow standard venipuncture procedures, others require special collection, handling, transport, or storage instructions to preserve specimen integrity and ensure accurate test results. These are known as special collections in phlebotomy.

Special collection procedures may involve timed blood draws, temperature-controlled transport, protection from light, specialized collection tubes, or additional documentation. Following these requirements helps reduce preanalytical errors that can affect laboratory results, delay diagnosis, or require repeat specimen collection. Organizations such as the World Health Organization (WHO) and the Clinical and Laboratory Standards Institute (CLSI) emphasize that proper specimen collection and handling are essential for quality laboratory testing and patient safety.

This study guide explains the principles of special collections, reviews the most common specimen types that require unique handling, and highlights practical tips that are frequently tested on phlebotomy certification exams. If you’re new to phlebotomy, start with our Phlebotomy Study Guide to build a strong foundation before exploring this topic. After finishing this guide, reinforce your knowledge by taking our Phlebotomy Practice Exam to assess your understanding with exam-style questions.

What Are Special Collections in Phlebotomy?

Special collections are blood specimens that require procedures beyond routine venipuncture to ensure accurate laboratory testing. Depending on the test ordered, these procedures may include specific patient preparation, timed specimen collection, specialized collection tubes, temperature-controlled transport, protection from light, rapid delivery to the laboratory, or additional documentation.

Unlike routine blood tests, special collections have unique requirements because certain analytes can change quickly after collection or become affected by environmental conditions. For example, some specimens must be kept warm or transported on ice, while others need protection from light or must be collected at a precise time in relation to medication administration. Following these instructions helps preserve specimen integrity so the laboratory can produce reliable results.

If you want to check your understanding as you study, take our Special Collections Quiz for exam-style practice questions covering specimen handling, transport requirements, timed collections, and common collection errors.

Special collection requirements are determined by the laboratory and the test being performed. Phlebotomists should always review the test order and follow their facility’s policies, laboratory procedures, and manufacturer instructions when collecting these specimens. Adhering to established protocols helps reduce preanalytical errors, improve specimen quality, and support accurate clinical decision-making.

How Are Special Collections Different from Routine Blood Collection?

Although both routine and special collections follow the same core principles of patient identification, infection prevention, and safe venipuncture, special collections include additional handling requirements that are specific to the test being performed.

Routine Blood Collection	Special Collections
Standard collection procedures	Test-specific collection requirements
Normal specimen transport	May require ice, warming, or light protection
Standard timing	May require collection at an exact time
Routine collection tubes	May require specialized tubes or containers
Standard documentation	May require additional forms or chain of custody records

Understanding these differences is essential because even a correctly performed venipuncture can produce an unsuitable specimen if special handling requirements are not followed. Proper collection and specimen management help ensure laboratory results accurately reflect the patient’s condition and reduce the need for repeat blood draws.

Why Are Special Collections Important?

Special collection procedures help ensure that blood specimens accurately represent a patient’s condition at the time of collection. Many laboratory tests measure substances that can change if a specimen is collected, handled, transported, or processed incorrectly. Following the required collection instructions preserves specimen integrity and helps the laboratory produce reliable results that healthcare providers can use to make informed clinical decisions.

Proper specimen handling also supports patient safety. If a specimen is contaminated, mislabeled, exposed to the wrong temperature, or delayed during transport, the laboratory may reject it or report results that do not accurately reflect the patient’s condition. This can lead to repeat blood draws, delayed diagnosis, additional healthcare costs, and unnecessary inconvenience for the patient.

Many of these issues occur during the preanalytical phase—the period from test ordering through specimen collection, labeling, transport, and processing. Because most laboratory testing errors occur before the sample is analyzed, phlebotomists play a critical role in following established collection procedures and laboratory protocols to minimize preventable errors.

Benefits of Following Special Collection Procedures

• Maintains specimen integrity by reducing contamination and analyte degradation.
• Supports accurate laboratory results for diagnosis, treatment, and patient monitoring.
• Reduces preanalytical errors, including incorrect timing, improper transport, or unsuitable specimen handling.
• Decreases repeat blood collections, improving the patient experience and reducing delays.
• Promotes compliance with laboratory quality standards and facility-specific collection procedures.

Continue Learning: Proper collection is only the first step in obtaining a high-quality specimen. After collection, correct labeling, transport, storage, and laboratory processing are equally important for maintaining specimen integrity. Learn more in our Specimen Processing Study Guide, then reinforce your knowledge with the Specimen Processing Quiz to practice exam-style questions on specimen handling, transport, and quality assurance.

Exam Tip: Certification exams often ask why a specimen requires special handling—not just how to collect it. Understanding the purpose behind procedures such as transporting a specimen on ice, protecting it from light, or collecting it at a specific time will help you answer scenario-based questions with greater confidence.

General Principles for Special Collections

Although each laboratory test has its own collection requirements, most special collections follow the same core principles. Understanding these fundamentals helps phlebotomists collect high-quality specimens, reduce preanalytical errors, and ensure that laboratory results accurately reflect the patient’s condition.

Before collecting any special specimen, always review the laboratory’s collection instructions and follow your facility’s policies. Requirements such as patient preparation, collection timing, specimen temperature, transport conditions, and documentation may vary depending on the test and laboratory protocol.

1. Verify the Test Requirements

Every special collection begins by confirming the laboratory order and reviewing the specific collection instructions. Some tests require fasting, while others must be collected at a precise time or transported under controlled temperature conditions. Reviewing these requirements before performing venipuncture helps prevent collection errors and unnecessary repeat procedures.

2. Confirm Patient Identification and Preparation

Accurate patient identification is essential for every blood collection. Verify the patient’s identity using your facility’s approved identification process before collecting the specimen. Also confirm that any required preparation—such as fasting, medication timing, or activity restrictions—has been completed according to the test instructions.

Related Guide: Before collecting any specimen, proper patient preparation is essential for obtaining reliable laboratory results. Review our Phlebotomy Patient Preparation Study Guide to learn about fasting requirements, patient identification, and pre-collection instructions.

3. Select the Correct Collection Tube

Using the correct collection tube is critical because different additives preserve or stabilize specific analytes. An incorrect tube can affect specimen quality and may result in inaccurate laboratory results or specimen rejection. Always verify the required tube type before collection and follow the recommended order of draw when multiple tubes are collected.

4. Follow Timing Requirements

Some laboratory tests must be collected at a specific time to provide clinically meaningful results. For example, therapeutic drug monitoring relies on specimens collected at designated peak or trough times, while glucose tolerance testing requires blood samples at scheduled intervals. Recording the correct collection time is equally important for these tests.

5. Maintain Required Temperature Conditions

Certain specimens must remain at a specific temperature after collection to preserve the analyte being measured. Depending on the laboratory protocol, a specimen may need to be transported on ice, maintained at room temperature, or kept warm until processing. Following these requirements helps maintain specimen stability and reduces the risk of inaccurate results.

6. Protect Light-Sensitive Specimens

Some analytes break down when exposed to light. In these cases, specimens should be protected immediately after collection using amber-colored containers or an approved light-blocking material, following the laboratory’s instructions.

7. Transport and Process Specimens Promptly

Proper transport is just as important as proper collection. Delays in transportation or processing may affect specimen quality and test accuracy. After collection, label the specimen immediately and deliver it to the laboratory according to the required transport conditions and turnaround times.

Continue Learning: Want to understand what happens after a blood sample leaves the collection chair? Explore our Specimen Processing Study Guide and test your knowledge with the Specimen Processing Quiz to learn how proper handling, transport, and processing help maintain specimen quality.

Blood Culture Collection

Blood cultures are collected to detect bacteria or fungi in the bloodstream when a healthcare provider suspects a bloodstream infection (bacteremia) or sepsis. Unlike routine blood tests, blood culture collection requires meticulous attention to aseptic technique because contamination can produce false-positive results, leading to unnecessary antibiotic treatment, additional testing, and increased healthcare costs.

Before collecting blood cultures, verify the patient’s identity, confirm the test order, and prepare the collection equipment. Proper skin antisepsis is one of the most important steps in the procedure. The venipuncture site should be disinfected according to your facility’s protocol, and care should be taken to avoid contaminating the sterile collection equipment after skin preparation. The Centers for Disease Control and Prevention (CDC) recommends standardized collection practices to help reduce blood culture contamination.

Whenever clinically appropriate, blood cultures are ideally collected before antimicrobial therapy is started, as antibiotics may reduce the likelihood of recovering microorganisms from the bloodstream. The number of blood culture sets, collection site, and collection timing should always follow the ordering provider’s instructions and your laboratory’s protocol.

Key Points to Remember

• Collect blood cultures using strict aseptic technique.
• Proper skin disinfection helps reduce specimen contamination.
• When clinically appropriate, collect specimens before antibiotic therapy begins.
• Follow your laboratory’s protocol for the number of culture sets and collection procedure.
• Label and transport specimens promptly according to laboratory requirements.

Exam Tip: Blood culture questions often focus on preventing contamination rather than the venipuncture procedure itself. Understanding why aseptic technique and proper skin preparation are essential will help you answer scenario-based exam questions more accurately.

Glucose Tolerance Test (GTT)

A Glucose Tolerance Test (GTT) measures how effectively the body processes glucose over time. Healthcare providers commonly use this test to help evaluate conditions such as diabetes mellitus, prediabetes, or gestational diabetes. Unlike routine blood tests, a GTT requires blood specimens to be collected at specific time intervals, making accurate timing one of the most important parts of the procedure.

Before the test begins, patients may need to follow specific preparation instructions, such as fasting for the period specified by the healthcare provider or laboratory. After an initial fasting blood sample is collected, the patient drinks a glucose solution, and additional blood samples are collected according to the laboratory’s testing schedule. The number of specimens collected and the timing of each collection depend on the type of glucose tolerance test ordered.

Because the test measures changes in blood glucose over time, maintaining the correct collection schedule is essential. Missing a scheduled collection time or failing to follow patient preparation instructions can affect the interpretation of the results. During the test, patients should also follow the laboratory’s instructions regarding eating, drinking, smoking, physical activity, and remaining at the testing location.

Key Points to Remember

• A GTT is a timed collection that requires blood samples at scheduled intervals.
• Verify that the patient has completed any required preparation before beginning the test.
• Record the collection time accurately for each specimen.
• Follow the laboratory’s testing schedule and collection instructions throughout the procedure.
• Label and transport each specimen according to laboratory protocol.

Related Guide: Proper fasting instructions and patient preparation are essential for many laboratory tests, including the Glucose Tolerance Test. Review our Phlebotomy Patient Preparation Study Guide to learn more about fasting requirements, patient instructions, and factors that may influence test results.

Exam Tip: On certification exams, Glucose Tolerance Test questions often emphasize patient preparation and accurate specimen timing rather than the glucose values themselves. Focus on understanding when specimens are collected and why following the testing schedule is critical for accurate results.

Therapeutic Drug Monitoring (TDM)

Therapeutic Drug Monitoring (TDM) is used to measure the concentration of certain medications in a patient’s bloodstream. The goal is to help healthcare providers determine whether a drug level is within the therapeutic range—high enough to be effective while minimizing the risk of toxicity or inadequate treatment. TDM is commonly performed for medications that have a narrow therapeutic index, meaning small changes in drug concentration can significantly affect patient outcomes.

Unlike routine blood tests, TDM requires specimens to be collected at specific times in relation to medication administration. The two most common timed collections are:

• Peak Level: Collected after a medication has been administered, when the drug concentration is expected to be at or near its highest level. The exact collection time varies depending on the medication and the laboratory’s protocol.
• Trough Level: Collected immediately before the next scheduled dose, when the drug concentration is expected to be at its lowest level.

Accurate timing is essential because collecting the specimen too early or too late can produce results that do not accurately reflect the patient’s drug level. Before collecting a TDM specimen, verify the medication schedule, document the collection time, and follow your facility’s policies and laboratory instructions.

Key Points to Remember

• Therapeutic Drug Monitoring helps evaluate whether medication levels are within the therapeutic range.
• Peak specimens are collected after medication administration according to the prescribed collection schedule.
• Trough specimens are collected immediately before the next scheduled dose.
• Always record the collection time accurately and follow the laboratory’s testing protocol.
• Incorrect specimen timing may affect the interpretation of test results.

Exam Tip: Certification exams frequently test the difference between peak and trough drug levels. Remember that a trough level is collected immediately before the next dose, while the timing of a peak level depends on the specific medication and laboratory protocol.

Ammonia Specimen Collection

An ammonia test measures the amount of ammonia in the blood and is commonly used to help evaluate liver function, certain metabolic disorders, and unexplained changes in mental status. Because ammonia levels can change after blood is collected, proper specimen handling is essential for obtaining reliable laboratory results.

Many laboratories require ammonia specimens to be transported on ice and delivered promptly for processing. Delays or improper handling may affect specimen stability and lead to inaccurate test results. Before collecting the specimen, always verify the laboratory’s collection instructions and follow your facility’s protocol for tube selection, transport, and processing.

Key Points to Remember

• Ammonia specimens often require immediate transport on ice.
• Deliver the specimen to the laboratory as quickly as possible.
• Follow your laboratory’s instructions for collection, handling, and processing.
• Prompt handling helps maintain specimen integrity and supports accurate test results.

Exam Tip: When you see an ammonia specimen on a certification exam, think “collect promptly and transport on ice.” Questions commonly focus on proper specimen handling rather than the disease being evaluated.

Lactic Acid Specimen Collection

A lactic acid (lactate) test measures the level of lactate in the blood and is commonly used to help evaluate conditions associated with poor tissue oxygenation, such as sepsis or shock. Because lactate levels can be affected by specimen handling, following the laboratory’s collection instructions is essential.

Many laboratories require lactic acid specimens to be transported on ice and processed promptly to help preserve specimen integrity. Prolonged tourniquet application and delays in processing may also influence test results. Always follow your facility’s protocol for patient preparation, specimen collection, transport, and processing.

Key Points to Remember

• Many laboratories require transport on ice.
• Process and deliver the specimen promptly.
• Avoid unnecessary prolonged tourniquet application.
• Follow laboratory-specific collection and handling instructions.

Exam Tip: Don’t confuse lactic acid and ammonia questions. Both may require prompt handling, but always follow the laboratory’s protocol for each specific test.

Bilirubin Specimen Collection

A bilirubin test measures the level of bilirubin in the blood and is commonly used to evaluate liver function, bile duct disorders, and hemolytic conditions. Because bilirubin is light sensitive, protecting the specimen from light after collection is essential to help maintain accurate test results.

Depending on the laboratory’s protocol, the specimen may be placed in an amber-colored collection tube or wrapped in an approved light-protective material immediately after collection. Exposure to light can cause bilirubin to break down, potentially affecting the accuracy of laboratory results. Always follow your facility’s instructions for specimen handling, transport, and storage.

Key Points to Remember

• Bilirubin is a light-sensitive specimen.
• Protect the specimen from light immediately after collection.
• Follow laboratory guidelines for transport and storage.
• Proper handling helps preserve specimen integrity and improve result accuracy.

Exam Tip: If an exam question asks which specimen should be protected from light, bilirubin is one of the most common answers. Remember the phrase “Bilirubin = Block the Light.”

Cold Agglutinin Specimen Collection

A cold agglutinin test detects antibodies that can cause red blood cells to clump together at low temperatures. To help ensure accurate results, the specimen must be collected and handled according to the laboratory’s temperature requirements.

Unlike specimens that are transported on ice, cold agglutinin specimens are typically kept warm until they reach the laboratory or are processed according to laboratory protocol. Allowing the specimen to cool before processing may affect the test results. Always verify the collection instructions and follow your facility’s procedures for temperature control and specimen transport.

Key Points to Remember

• Cold agglutinin specimens are typically kept warm, not chilled.
• Maintain the required temperature during transport according to laboratory protocol.
• Follow your laboratory’s collection and handling instructions carefully.
• Proper temperature control helps preserve specimen quality and supports accurate testing.

Exam Tip: A common certification exam question compares cold agglutinin and ammonia specimens. Remember the difference: cold agglutinin specimens are kept warm, while ammonia specimens are commonly transported on ice.

Trace Element Specimen Collection

Trace element tests measure very small amounts of minerals or metals in the blood, such as zinc, copper, or lead. Because these substances are present in tiny concentrations, even minor contamination during collection can affect the accuracy of the test results.

To minimize contamination, many laboratories require the use of trace element collection tubes, such as royal blue-top tubes, when appropriate for the ordered test. Phlebotomists should also avoid contaminating the specimen by following proper collection techniques and the laboratory’s instructions for handling and transport.

Key Points to Remember

• Trace element specimens require careful collection to prevent contamination.
• Use the collection tube specified by the laboratory, which may include a royal blue-top tube.
• Follow laboratory instructions for specimen handling and transport.
• Proper collection techniques help ensure accurate laboratory results.

Exam Tip: If a question asks which specimen requires extra care to avoid contamination, think of trace element testing and the use of specialized collection tubes.

Newborn Screening

Newborn screening is performed to identify certain genetic, metabolic, hormonal, and other serious conditions shortly after birth. Early detection allows many of these conditions to be treated before they cause significant health problems.

Unlike routine venipuncture, newborn screening is typically performed using a heel stick. Blood drops are collected onto a specially designed filter paper card that is sent to a laboratory for analysis. To help ensure accurate results, the blood spots should completely fill the designated circles, and the card should be allowed to air dry according to the laboratory or screening program’s instructions before packaging and transport.

Key Points to Remember

• Newborn screening is usually performed using a heel stick.
• Collect blood on the approved filter paper card.
• Allow the blood spots to air dry completely before transport.
• Follow your facility’s and newborn screening program’s collection guidelines.

Exam Tip: If a certification exam asks about filter paper cards or heel stick collections, the correct answer is often newborn screening. Proper blood spot collection and drying are essential for accurate screening results.

Chain of Custody Collections

A chain of custody collection is used when a specimen must be tracked from the time it is collected until testing is complete. These collections are commonly performed for workplace drug testing, forensic investigations, and other legal or regulated testing, where maintaining specimen identity and integrity is essential.

Unlike routine blood collections, chain of custody procedures require additional documentation and secure specimen handling. The collector must verify the patient’s identity, label the specimen correctly, complete the required paperwork, and ensure the specimen remains sealed and properly documented throughout transport. Following these procedures helps maintain a clear record of everyone who handled the specimen and reduces the risk of tampering or misidentification.

Key Points to Remember

• Chain of custody collections require continuous documentation of specimen handling.
• Verify patient identity before specimen collection.
• Label, seal, and document the specimen according to the testing protocol.
• Maintain specimen security throughout transport and testing.

Exam Tip: Questions about legal documentation, specimen security, or workplace drug testing often relate to chain of custody collections. Focus on accurate identification, proper documentation, and maintaining an unbroken record of specimen handling.

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Common Mistakes to Avoid During Special Collections

Even when venipuncture is performed correctly, mistakes during specimen collection or handling can affect laboratory results and require the specimen to be recollected. Understanding these common errors helps phlebotomists maintain specimen quality and support accurate patient care.

Using the Wrong Collection Tube

Selecting an incorrect collection tube or additive may compromise the specimen and lead to inaccurate test results or specimen rejection. Always verify the required tube before collection.

Incorrect Specimen Timing

Some tests, such as Glucose Tolerance Tests (GTT) and Therapeutic Drug Monitoring (TDM), depend on specimens being collected at specific times. Collecting the sample too early or too late may affect result interpretation.

Improper Temperature Control

Certain specimens require special temperature conditions during transport. For example, ammonia specimens are commonly transported on ice, while cold agglutinin specimens are typically kept warm according to laboratory protocol.

Failure to Protect Light-Sensitive Specimens

Specimens such as bilirubin should be protected from light immediately after collection. Failure to do so may reduce specimen stability and affect test accuracy.

Delayed Transport or Processing

Some special collections require prompt delivery to the laboratory. Delays in transport or processing may reduce specimen quality and increase the likelihood of specimen rejection.

Documentation Errors

Incomplete labeling or missing collection times can delay testing and, in some cases, require a repeat specimen. Always label specimens immediately after collection and complete any required documentation accurately.

Continue Learning: Many of these errors occur after blood collection but before laboratory analysis. Read our Specimen Processing Study Guide to learn how proper transport, storage, and processing help maintain specimen quality, then test your knowledge with the Specimen Processing Quiz.

Special Collections Quick Reference Table

Special Collection	Special Requirement	Why It Matters
Blood Cultures	Use strict aseptic technique and follow laboratory collection procedures.	Helps reduce specimen contamination and improve culture accuracy.
Glucose Tolerance Test (GTT)	Collect specimens at the scheduled time intervals.	Accurate timing is essential for interpreting glucose metabolism.
Therapeutic Drug Monitoring (TDM)	Collect peak and trough specimens according to the medication schedule.	Drug levels are only meaningful when collected at the correct time.
Ammonia	Commonly transported on ice and processed promptly.	Helps preserve specimen stability and supports reliable results.
Lactic Acid	Often requires prompt transport and laboratory processing.	Delayed handling may affect lactate measurements.
Bilirubin	Protect the specimen from light immediately after collection.	Light exposure can reduce bilirubin concentration.
Cold Agglutinin	Maintain the specimen at the required warm temperature according to laboratory protocol.	Temperature changes may affect test accuracy.
Trace Elements	Use the specified trace element collection tube and avoid contamination.	Prevents contamination that could alter test results.
Newborn Screening	Collect blood on an approved filter paper card and allow it to air dry.	Proper collection and drying help ensure accurate screening results.
Chain of Custody	Verify identity, document handling, and maintain specimen security.	Preserves specimen integrity for legal or regulated testing.

Study Tip: Use this table as a quick review before your certification exam. Focus on matching each specimen with its special handling requirement, as this is a common format for scenario-based exam questions.

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Certification Exam Tips

Special collections are a common topic on phlebotomy certification exams because they assess your ability to collect and handle specimens correctly. Rather than memorizing isolated facts, focus on why each specimen requires special handling and how improper collection could affect laboratory results.

Keep these high-yield points in mind during your exam:

• Know the purpose of each special collection. Understand why tests such as blood cultures, therapeutic drug monitoring, or bilirubin testing require unique handling procedures.
• Recognize temperature-sensitive specimens. Be able to identify which specimens may require transport on ice, protection from light, or controlled temperature handling according to laboratory protocol.
• Understand timed collections. Review when timing is critical, especially for Glucose Tolerance Tests (GTT) and Therapeutic Drug Monitoring (TDM).
• Prioritize specimen integrity. Remember that correct tube selection, labeling, transport, and documentation are just as important as the venipuncture itself.
• Read scenario-based questions carefully. Many exam questions describe a clinical situation rather than asking for a direct definition. Look for clues about specimen handling, timing, or transport requirements before choosing your answer.

Practice Your Knowledge: Reading alone isn’t enough to master special collections. Reinforce what you’ve learned by taking our Special Collections Quiz, then challenge yourself with the Phlebotomy Practice Exam to experience exam-style questions covering all major phlebotomy topics.

Frequently Asked Questions (FAQs)

Key Takeaways

Before moving on to your next study topic, remember these essential points about special collections in phlebotomy:

• Special collections require procedures beyond routine venipuncture, such as timed collection, temperature control, light protection, or specialized documentation.
• Always follow your laboratory’s collection protocols to maintain specimen integrity and ensure accurate test results.
• Proper specimen handling helps reduce preanalytical errors, prevent specimen rejection, and support safe patient care.
• Common special collections include blood cultures, Glucose Tolerance Tests (GTT), Therapeutic Drug Monitoring (TDM), ammonia, lactic acid, bilirubin, cold agglutinin, trace element testing, newborn screening, and chain of custody collections.
• Understanding why each specimen requires special handling is just as important as knowing how to collect it.

Ready to continue your exam preparation? Strengthen your knowledge by reviewing our Phlebotomy Study Guide, testing yourself with the Special Collections Quiz, or challenging yourself with the Phlebotomy Practice Exam to build confidence before certification day.