CALIPER (Canadian Laboratory Initiative on Pediatric Reference Intervals) is a nation-wide initiative to improve the diagnosis and care of children, both at SickKids and at healthcare centres across Canada and globally. Our main objective is to establish a comprehensive database of healthy reference standards (normal ranges) for blood test results in children and adolescents.

Reference Standards

What is a reference standard?

A reference standard is a range of blood test result values that inform doctors what should normally be seen in a healthy population. When a child visits a doctor’s office to diagnose a medical problem or for a routine check-up, they’ll ask for a blood sample, which is then sent to a laboratory for testing. The results of that test can then be used to diagnosis, monitor and treat medical concerns.

Other common terms for reference standards: reference intervals, reference values

Why do we need reference standards?

In order to deliver the best possible health-care to children and adolescents, accurately and reliably reading blood test results is essential. This requires reference standards. By comparing a set of test results to a reference standard, doctors can more accurately identify and diagnose medical concerns.

How does CALIPER develop reference standards?

CALIPER collects blood samples from healthy children from birth to 18 years of age to establish a comprehensive database of standard test values—a guide for health-care professionals that can be used to compare blood test results to an appropriate health standard.

Example reference interval and test result value for iron as it would appear in the CALIPER mobile app

Gaps & Initiatives

In the past, laboratories and healthcare professionals have relied on adult reference ranges or scattered and incomplete data as a source of paediatric reference standards. This increases the risk of misdiagnosis and can result in unnecessary stress, lengthier hospital stays, and increased costs to the health-care system.

CALIPER, as well as a number of other initiatives, has made significant progress in establishing paediatric reference standards. Despite this, gaps still exist in paediatric reference intervals and the evaluation of paediatric test results. We’re making a push to fill these gaps, alongside a number of other initiatives.

History & Achievements


The CALIPER project was initiated by clinical chemists and medical biochemists from the Paediatric Focus Group of the Canadian Society of Clinical Chemists (CSCC).

This led to three workshops that were held from 2004 to 2006 among paediatric hospital laboratories on establishing a new laboratory reference interval database for biomarkers of paediatric disease.

The group recommended collaborative studies to determine the effect of age, gender, and ethnic origin on blood test results in children, and establish a comprehensive database of paediatric reference intervals for Canadian children and adolescents. They called the national initiative the CALIPER (Canadian Laboratory Initiative on Pediatric Reference Intervals) project.


CALIPER has successfully established reference standards for hundreds of blood tests thanks to 12,000 children and adolescent participants and their families. This data is used by thousands of institutions around the world, and has received several awards and accolades.

children have participated
laboratory tests studied
peer-reviewed publications



  • CALIPER principal investigator, Dr. Khosrow Adeli, awarded a seven-year CIHR Foundation Grant (2016-2023) to further CALIPER initiatives
  • CALIPER awarded the 2015 Innovations Award by the Canadian Society of Clinical Chemists
  • Developed the first edition of the CALIPER app for iPhone and Android


  • Published the CALIPER White Paper
  • Completed the CALIPER Reference Interval Ethnicity study
  • Initiated the Lipid Metabolism in Adolescents Study


  • Launched the new CALIPER Pediatric Reference Interval Database and mobile app, used by thousands of institutions worldwide
  • CALIPER principal investigator, Dr. Khosrow Adeli, awarded the AACC Academy Outstanding Research Award
  • Launched new CALIPER studies, including the Mother and Child Health Initiative and the COVID-19 Study
  • CALIPER Mother and Child Health Initiative awarded a grant from March of Dimes