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FAQs: Repeat Blood Collection

Substudy Participation

Collecting blood samples and physical measurements in research studies allows researchers to understand how to better identify or treat cancer and other diseases. Studying factors in a blood sample helps researchers learn what a person may have been exposed to in their environment, through their diet, and more. While CPS-3 participants provided a blood sample and some physical measurements (e.g. waist measure) at initial enrollment in the study, some of these measurements may change over time because of changes in where or how you live. A single blood sample or physical measurement would not allow researchers to study changes over time. Thus, a repeat blood sample in a subset of CPS-3 participants would be highly valuable for future research efforts. 

1.      Sign Up

Sign up for and consent to join using the CPS-3 Participant Portal

2.      Schedule your blood draw

Receive a collection kit in the mail, which will include all materials needed. It will also include instructions for making an appointment at an ACS lab partner at a location that is convenient for you.

3.      Get your blood drawn

You will need your collection kit at the time of your appointment. A medical professional will draw 50ml (about 3.5 tablespoons) of blood. This is similar to the amount drawn during a routine doctor’s visit. The medical professional will also collect your physical measurements (your height, weight, waist circumference, and blood pressure).

4.      Take a brief survey

Within 24 hours after your blood draw, take a brief survey on the portal. This survey will ask about things that may impact your blood sample like what medications you’re taking and when you had your last meal before giving blood.

Please complete the survey as soon as you can. Try to answer the questions based on your experiences the day of your blood draw. While we want all participants to complete their survey within 24 hours of their blood draw, we will still be able to use the information you provide in your questionnaire if it is completed at a later time. However, if you do not complete the questionnaire, we will be unable to use your blood sample.

We will use your sample and data only for health research. Human blood is a time capsule that can tell us about your past  or present exposures and future disease risk.

  • Researchers will study your blood sample to look at the genetic information you were born with as well as changes that may have occurred in your body over time.
  • Researchers may also study your blood for things that naturally occur in your body (such as cholesterol, hormones, and markers of immunity) as well as things you may be exposed to during your lifetime like environmental pollutants or infections.

If you join this substudy, the blood sample and any information you provide are for research purposes only and you will not be entitled to compensation for any use, products, data, or other items or information that is developed from the sample or data. If products are developed, they would not be based on your data alone, but on data from multiple participants.

There will be no cost to you for participating in the substudy. However, there may be transportation costs to get to the blood donation facility.

Donating a blood sample is safe and considered minimally invasive. Only a trained medical professional (phlebotomist) will collect your sample. The most common risks from donating this amount of blood are slight bruising or brief pain. Some people may become dizzy or feel faint. There is also a very small risk of infection. 

Scientific tests that are used for large group research, like the type we will do in CPS-3, are not the same as an individual test done in your doctor's office. Therefore, we will not give you the results from group research projects you might be included in. 

However, we will keep you updated about any group research findings. As a CPS-3 participant, you will receive a quarterly CPS-3 e-newsletter with study highlights and updates. In addition, stories of important study findings can be found on


No, you do not need to adjust your habits before the blood draw. You can eat, drink, and exercise as you normally do.

If you have concerns about giving blood due to these or other conditions, please check with your healthcare provider before joining this substudy and providing a blood sample.

Yes. While a cancer diagnosis and cancer treatments may affect some things in your blood, there is still a lot we can learn from your sample. Please check with your healthcare provider before giving a blood sample.

Yes. Getting a sample on participants who we weren't able to at enrollment is valuable for many of the factors we may study in your blood sample. While we won't be able to look at how things (e.g. hormones) may have changed over time, your blood is like a time capsule that can give us insights into many things in your environment. 

Privacy & Security

Because research in CPS-3 will continue for at least thirty years, some methods used to study your sample may not be invented yet. Measuring things in the blood is very expensive, so not every person's blood will be included in every research project. We will freeze and securely store your blood sample at our biorepository until it is needed for a project.

A biorepository is a facility that collects and stores biological samples. Your sample will be labeled with your CPS-3 study ID. Your name and other identifying information will not be stored with the sample. 

Your physical measurements and survey information will be stored with the other deidentified CPS-3 data. This means that the information is also labeled with your study ID instead of your name and all identifying information is kept in a separate location. 

Our surveys are hosted on secure sites. All information is kept secure and confidential with limited access to study staff who sign confidentiality forms and undergo regular biomedical research ethics training. Every effort is made to protect the identity and personal information of the participants in this study.

When your data are collected, they are labeled with a unique identification number. Your data are then stored separately from all personal identifiers, such as your name, address, email address, and phone number. All study materials are stored in a locked facility and secured computer files, and your personal contact information is kept in separate files accessible only to a limited number of CPS staff. This personal contact information will not be shared with anyone, including other staff at the American Cancer Society, unless they are directly involved in managing CPS-3. 

Your genetic information (without your name or personal identifying information) will only be shared with researchers to advance science. However, there is an extremely small chance that someone could get unauthorized access to your genetic information, despite the safeguards that we have in place. 

Even if this were to happen, there is a federal a law, the Genetic Information Nondiscrimination Act (GINA), that makes it illegal for health insurance companies, group health plans, and most employers to discriminate against you based on your genetic information. It is important to know that the GINA law does not apply to other types of insurance companies (such as life or disability insurance) or employers with fewer than 15 employees.

Samples are stored at the time of collection and will be used for future research studies. Although we won't test for anything specific at the time of collection, your samples may be tested later for different types of drugs (e.g., prescription, over the counter, or other substances). Your sample and results will only be identified with a study ID. This information will be used for health research only and will not be shared or reported to your employer or law enforcement. 

To advance science, we may provide CPS-3 study samples and data to other researchers for additional projects. This may include putting deidentified data in controlled-access databases as required by many scientific journals and funding agencies. These requirements are made with the idea that the timely sharing of resources can accelerate discoveries that will improve our ability to diagnose, treat, and prevent disease. Researchers will need to sign data use agreements before accessing the data or samples. We will remove any personal information that could identify you before your information is shared. 

No, your participation in this substudy will not affect your access to healthcare or insurance coverage. We will not willingly share information related to your sample with these parties and have safeguards in place to ensure that your information is fully protected by the law.