“Big data” and a systems biology platform

CHILD’s wealth of longitudinal environmental, immunological, physiologic and genetic data, allows for both traditional and novel strategies of data analysis to test novel hypotheses related to DOHaD. The Study is actively participating in efforts to create standardized data definitions and transparent data dictionaries, in order to increase the utility and power of its datasets and maximize opportunities for collaboration.

CHILD data

Questionnaires

Detailed environmental and health questionnaires have been completed by CHILD Study subjects at 13 different time points from mid-pregnancy to 8 years, with more coming at age 12 and beyond. No similar study has analyzed the home environment of such a large pregnancy-based cohort at the same level of detail, with “environment” interpreted broadly to include physical, chemical, viral, bacterial, nutritional and psychosocial exposures. Other data collected by questionnaires include: mode of delivery; duration and exclusivity of breastfeeding; use of daycare; exposures to medications, especially antibiotics; maternal diet during pregnancy; and infant/child diet and growth. See the list of questionnaires used from pregnancy to age 12 years.

Access questionnaires (password protected)

Clinical measures

Clinical measures taken include general anthropometrics, allergy skin prick tests, blood pressure, waist circumference, skinfold thickness and lung function (spirometry).

Sample analysis

The data increasingly being generated by analysis of the Study’s biological samples, including through genetic and epigenetic studies, are retained by the Study and integrated into its bioinformatics platform.

Linkage to routine health & social records

Parents have provided permission to access appropriate databases for supplemental information.

For an overview of environmental factors assessed in the CHILD Study, see Takaro et al (Journal of Exposure Science and Environmental Epidemiology, Mar 2015).


Key variables obtained by questionnaire

Current residence
Previous residences (12mo)
Changes of residence
Type and age of home
Characteristics of home
Building materials
Garage characteristics
Heating/Cooling systems
Moisture and ventilation
Basement/crawl space
Water leaks and mold
Swimming pool, hot tub, sauna
Home improvements
Furniture
Cooking systems
Cleaning habits
Chemicals used/stored in home
Smoking in/near the home
Characteristics of bedroom
Occupancy (# people in home)
Pets in home
Insects and pests in home
Neighbourhood characteristics
Child bedroom dust
Most-used living area dust
Furry Pets in home 
Child bedroom dust 
Most-used living area dust 
NO2 exposure
Annual average temperature
Normalized difference vegetation index (NDVI)
Annual average ozone
Annual average PM2.5
Annual average SO2
Maternal demographics
Health/medical conditions (prenatal, during pregnancy, postpartum)
Maternal medications
Maternal smoking prior to/during pregnancy
Maternal respiratory syumptoms
Maternal diagnosed asthma
Maternal allergies
Maternal occupation
Family structure
Health of other children
Health during pregnancy
Diet before and during pregnancy (FFQ)
Vitamins and supplements
Breastfeeding
Pre/Postnatal maternal stress
Socioeconomic status
Depression
Labour and delivery
Post-partum stress
Parenting stress
Hobbies and activities in home
Parenting behaviour
Physical activity
Body composition
Blood pressure
Lung function (spirometry)
Height/weight
Allergy skin testing
Columbia Impairment Scale for child
Family eating habits/patterns
Tobacco/vaping/cannabis use and exposure
Smoking in/near the home 
Maternal medications 
Maternal smoking prior to/during pregnancy 
Maternal diagnosed asthma 
Maternal allergies 
Diet during pregnancy (FFQ) 
Maternal Depression 
Maternal Allergy skin testing 
Paternal demographics
Paternal health/medical conditions
Paternal medications
Paternal smoking prior to/during pregnancy
Paternal respiratory symptoms
Paternal diagnosed asthma
Paternal allergies
Paternal occupation
Family structure
Hobbies and activities in home
Parenting behaviour
Physical activity
Body composition
Blood pressure
Lung function (spirometry)
Height/weight
Allergy skin testing
Family eating habits/patterns
Tobacco/vaping/cannabis use and exposure
Paternal demographics 
Paternal diagnosed asthma 
Paternal allergies 
Paternal Allergy skin testing 
Mode of delivery
Child health/medical conditions
Medications around birth
Sleeping arrangements
Activities outside home
Colds and infections
Coughing episodes
Wheezing episodes
Medications
Vitamins and supplements
Food allergy
Atopic dermatitis/eczema/rhinitis
Doctor visits
Hospital/ER visits
Breastfeeding
Introduction of milk, solids
Diet (FFQ)
Vaccinations
Time/activity/locations
Travel times/modes/exposures
Sleep habits, behaviour, sleepiness
Screen time and sedentary behaviour
Activity levels
Behaviour
Daycare arrangements
School characteristics/location/class composition
Farm animal exposure
Physical activity
Height/weight
Skin folds
Head/Arm/Waist circumference
Body composition
Lung function (spirometry)
Asthma diagnosis (methacholine challenge)
Allergy skin testing
Blood pressure
Accelerometry/GPS (7 days)
Childhood Asthma Control Test
Body image (self-identified)
Gender (self-identified)
Puberty staging
Privacy
Anxiety (self-identified)
Columbia Impairment Scale (self-identified)
Bullying (self-identified)
Depression (self-identified)
School Performance
Eating habits/patterns
Smoke exposure 
Child health/medical conditions 
Medications around birth 
Coughing episodes 
Wheeze
Medications 
Allergy skin testing 
Atopic dermatitis/eczema/rhinitis 
Antibiotics in first year of life
Introduction of milk and solids 
Weight for age trajectories birth to 5 years
Lung function (spirometry) 
Asthma diagnosis (methacholine challenge) 
Food allergy 
Breastfeeding 

Download list of variables in Excel:

Key variables – CHILD Cohort Study