CHILD Banner


  1. 3624 families have been recruited which means over 9,600 people are participating in this study.

  2. All babies have been born and the 3 month home visits have been conducted in 3,313, 1 year assessments in 2,255 while 3-year visits are now beginning.

  3. The cohort has recruited over 9,600 individuals, including children and their parents. The recruited population is ethnically, environmentally, socioeconomically and culturally diverse; over 25% of parents report non-Caucasian ethnicity, reflecting the general structure of the Canadian population.

  4. The maternal prevalences of current asthma symptoms (15%) and atopy (56% have positive skin tests) are essentially the same as those in the Canadian population, indicating data will be generalizable.

  5. Over 300,000 aliquots of biological samples have been placed in liquid nitrogen storage, including cord blood from over 75% of the births, over 90% of all urine, stool, and nasal samples from the children, and 85% of possible breast milk samples. Blood samples were obtained from 66% of the 1058 1 year olds seen.


Data Tables

Population Demographics | Dwelling Demographics | Traffic Pollution


Study Progress

To learn about the overall progress of the CHILD Study, follow this link.

Knowledge into Action

One in three Canadians will be diagnosed with an allergic disease over their lifetime, on a level with diabetes, cancer and heart disease.. The prevalence of asthma has increased in most developed countries over the last 30 years. In one Canadian province, Ontario, the prevalence of asthma rose by 70.5% between 1996 and 2005, with increases in age and sex standardized prevalence of 8.5% to 13.3%.

The dramatic increase in asthma over just a few decades suggests new or changing environmental exposures. Although clearly environment and genetics interact in a complex manner, the developmental origins of atopic disorders remain unresolved. Despite many cross-sectional and several longitudinal studies, contradictions exist regarding risk factors for these high-morbidity childhood diseases.

Better understanding of causes of allergy and asthma can lead to earlier diagnoses, better management and the potential for development of preventive strategies. The CHILD Study will provide greater understanding of the root causes of allergy and asthma including biological and environmental triggers, translating into:

  1. BETTER HEALTH – One in three Canadians will be diagnosed with an allergic disease over their lifetime, on a level with diabetes, cancer and heart disease. Better understanding of the causes of allergic diseases can lead to earlier diagnoses, better disease management and the potential for development of preventive strategies, translating directly into better health.

  2. BETTER POLICIES– The incidence of allergic diseases is growing. Canada has one of the highest growth rates per capita for these diseases in the world. Better information about causes can lead to policies that generate social and environmental changes that in turn, can slow or reverse the growth of these diseases.

  3. LOWER HEALTH CARE COSTS –There are an estimated 275,000 ED visits annually in Canada for asthma and allergies (the majority are children), with a direct cost of approximately $275 million annually (using a conservative average cost per ED visit of $1,000). Even a 10% reduction in ED visits will result in a direct cost savings of $27 million annually on healthcare care budgets. Indirect savings are substantially greater.

  4. COMPREHENSIVE DATA: Linkage of CHILD data with provincial records of health services and pharmaceutical drug use, and knowledge of parental occupational and residential exposures, psychosocial stress and dietary history will provide a powerful dataset to examine multiple environmental epidemiologic questions in a wide variety of adult chronic diseases beyond asthma and allergies, e.g., diabetes, cancer, obesity, hypertension and cardiovascular disease.

The CHILD platform will be relevant to many different health researchers and disciplines, and to policy makers with respect to environment and health, including the impact of chronic diseases and exposures on the healthcare burden in Canada. Primary data emerging from the CHILD Study will potentially be influential in a wide variety of areas, including but not limited to
  • Public health-based prevention strategies for asthma & allergic diseases
  • Environmental exposure regulations & policies
  • Safe home product standards & regulations
  • Food safety regulations & policies
  • Personalized healthcare
  • Urban planning & home design

  • Maternal-child health in Canada & globally
  • Prenatal care (diet, nutrition) guidelines
  • Pediatric allergy & asthma guidelines

  • Novel therapeutic targets for drug discovery & exposure modulation
  • Strengthen medical education curricula

Data are highly relevant to several government agencies including:

  • Canadian Mortgage Housing Corporation (CMHC)
  • Federal - Health Canada, Environment Canada, Public Health Agency of Canada (PHAC), and
  • Provincial - Ministries of Health, Environment and Science and Technology


CHILD Logo and Tag