Children & Families

Children & Families

Participant Information

Are you interested in participating in CALIPER?

There are many sick children across Canada and around the world. CALIPER offers one way for you to provide your support. By donating a small blood sample to the CALIPER program, you’ll be helping doctors worldwide diagnose and treat sick children.

For more information on participating in CALIPER, please see the information below or get in touch with our team today!

Who can participate?

Inclusion criteria

  • Healthy children (determined based on questionnaire responses)
  • Children who are 0 to 18 years old

Who cannot participate?

Exclusion criteria

  • Children with a history of chronic illness or metabolic disease
  • Children who have had an acute illness within the past month
  • Children who have taken prescribed medication in the past month

What does participation involve?

Participant FAQs

CALIPER aims to improve the diagnosis and treatment of children across Canada. We are trying to determine what is normal and healthy when a child is screened for a disease. Our findings are used by doctors in order to compare healthy and normal blood levels to those of their sick patients.

In a case where we find something of concern or abnormal with your child’s blood, your family physician will be contacted. They are able to share that information with you and choose the appropriate action to take.

The amount of blood varies with age but ranges from 1mL (newborns and infants) to 11mL (11-18 years of age). Generally, it is approximately a tablespoon of blood.

This varies with each child. Some say it feels like a mosquito bite and others say it feels like a pinch. We use a needle called the butterfly needle, which is used on babies when treated at hospitals. It is the smallest type of needle and pain is minimal.

Most children do not feel sick after donating, since only a small amount of blood is taken. However, some children may feel anxious, scared, and nervous and sometimes feel faint or nauseous after donating. These reactions usually only last minutes and rarely occur. Generally, children are able to return to their normal daily activities immediately after donating blood.

We have fully trained phlebotomists who are a part of the CALIPER team and employed by SickKids Hospital that will draw the blood. Our staff are experienced with children and are professionals in their field.

The whole process usually takes about 10 minutes. However, the blood draw itself only takes approximately 30 seconds.

Yes, of course. We take blood from any child who wishes to donate. However, their blood may not be used towards our paediatric reference database since it is not “normal” but may be used in future tests to help other children with illnesses.

Yes. Contact us at to schedule an appointment for your child to donate here at the hospital.

Yes. Your child can withdraw from participating at any time. They will still receive their gifts for being brave enough for trying.

So far, we have tested hundreds of markers within the blood. This includes hormones, vitamins, minerals, proteins, amino acids, etc. These levels ultimately look at serum chemistry, enzymes, proteins, and lipid analytes.

You can find the results of our paediatric reference intervals on This information is being used by doctors across Canada and all over the world.

Our database is accessible to everyone. You can access it at

Yes. All data entered will be confidential and results published are anonymous.

This is an ongoing project that is expanding throughout Canada. We are trying to obtain information that is representative of the Canadian youth population. Having as many children as possible participate will increase the accuracy of our results.

Do you have more questions?