4-years follow up: Building the phenotype

We invited children and their families to participate in hands on neurodevelopment assessment, physical examination, and biological sample collection from October 2011 until December 2012. The planned visit for each child at the University Hospital of Heraklion or at medical centers lasted for 2 hours and 929 children were evaluated.

Children’s abilities were evaluated through the McCarthy scale (McCarthy Scales of Children Abilities - MSCA) (McCarthy, 1972). Two trained psychologists administered the 18 items of the McCarty scale, that are by design able to evaluate 6 domains (a) verbal, (b) quantitative, (c) memory (d) perceptive- performance, (e) motor abilities and (f) general cognition. Parents were informed for the performance of their children.

Also parents filled two questionnaires regarding the presence and the severity of certain symptoms and behaviors of their children; the Attention-Deficit/Hyperactivity Disorder Test (ADHDT) and the Strengths and Difficulties Questionnaire (SDQ).

Measurements that were focused on several health outcomes were carried out and included (a) growth and body composition measurements [weight, height, head, waist and mid-upper arm circumference and skinfold thickness at four sites of the body (subscapular, triceps, suprailiac and thigh)], (b) screening and scoring for atopic dermatitis (Hywell Williams Criteria and SCORAD tool), (c) blood pressure measurements and (d) spirometry performance for lung function evaluation.

Blood and urine samples have been collected from children whose parents agreed on that. Lipids and lipoproteins, micronutrients (P, Ca, Mg, Fe, Folic acid), adipokines, some inflammatory markers, thyroid hormones and persistent organic pollutants were the basic biomarkers analyzed in those samples.

In the parent questionnaire we updated addresses and information on some basic socio-demographic characteristics. We also asked about:

  • diet
  • physical activity
  • lifestyle (sleeping, TV watching, nursery attendance)
  • water consumption and use
  • sun exposure
  • childhood diseases, infections and treatment
  • allergies, wheezy breathing, atopic dermatitis, food allergies
  • housing conditions (pets, smoking, moisture in house, cleaning products)
  • diseases in parents (asthma, allergies, rhinitis)

6-years follow up: extending knowledge and capturing complexity

On the 6th of February 2014, we started sending invitations for participation to the 6th year follow-up. Please contact with us if you are a participant and you would like more information on the current assessment or if you would like to take part as a member of our research team.

Computer tests [(N-BACK), Attention Network Test, Trail Making Test, Raven’s Test] are used to assess three main functional domains of the children; a) attention and working memory, b) executive function, which is an umbrella term for cognitive functions that regulate, control, and manage other cognitive processes and c) visual reasoning, as a proxy of perceptive-performance IQ. These computer tests are internationally standardized and friendly for the child.

Parents complete the Conners’ (Conners 1997) and Child Behaviour Checklist (CBCL – Achenbach 2000) questionnaires to assess child behavioral and emotional problems. Also, the mother is performing a short version of a computer test (N-BACK) in order to provide us a proxy-measure of maternal IQ or cognitive functioning.

Physical examination includes (a) growth and body composition measurements (weight and height, head, waist and mid-upper arm circumference, skinfold thickness at four sites of the body and fat mass by bioelectrical impendence) (b) blood pressure measurements (c) spirometry performance for lung function evaluation.

We collect blood and urine samples from children whose parents agreed on that. Also we will collect hair samples from some children as well.

Standardized computer-assisted interviews with the mothers and/or fathers are collecting information on exposure sources and the following subject areas:

  • Breast feeding and parity history
  • Diet of child
  • Physical Activity of child
  • Sleeping patterns of child
  • Socioeconomic status
  • Social Capital of family
  • Stress of mother
  • Smoking
  • Water use
  • Cooking, heating, cleaning
  • Bedroom location
  • Noise perception
  • Electromagnetic fields radiation
  • Travel, places visited
  • Use of green spaces
  • Holidays and sun exposure behaviour
  • Asthma/immune system health outcomes of child
  • Siblings: growth measurements from medical records

Parents are also asked to identify in an online map the location of their house, the school, the usual commuting routes from home to school and the usual visited places and green spaces of their child. This procedure, called geocoding, uses the software QGIS (a source of Geographic Information System) and will provide us with information regarding outdoor exposures.