Table 1

Secondary outcomes

OutcomeDefinition
Outcomes to be measured at infancy (at 1 year of age)
Hospitalisation for bronchiolitis, viral-induced wheeze or asthma in the first year of lifeProportion of participants with at least one hospitalisation for bronchiolitis, viral-induced wheeze or asthma by 1 year of age using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset.’
Prescription for asthma medication in the first year of lifeProportion of participants completing at least one prescription for ICS, SABA, LABA or montelukast in the first year of life, by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection.’
Eczema in the first year of lifeThe proportion of participants whose parent/caregiver answers ‘yes’ to the questions ‘In the last year, has your child had an itchy skin condition—by itchy, we mean scratching or rubbing the skin?’ and IF YES ‘Has this skin condition ever affected the skin creases in the past—by skin creases we mean fronts of elbows, behind the knees, fronts of ankles, around the neck or around the eyes?’ using the UK Diagnostic Criteria for Eczema Questionnaire.32
Hospitalisation for eczema in the first year of lifeProportion of participants with at least one hospitalisation for eczema in the first year of life using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’.
Prescription for eczema medication in the first year of lifeProportion of participants completing at least one prescription for topical steroids in the first year of life, by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection’.
Outcomes to be measured at early childhood (at 3 years of age)
Wheeze at 3 years of ageThe proportion of participants whose parent/caregiver answers ‘yes’ to the question ‘Has your child had wheezing or whistling in the chest in the past 12 months?’ using the ISAAC Phase III Core Questionnaire for Asthma for children 6–7 years old.16
Hospitalisation for bronchiolitis, viral-induced wheeze or asthma in the first 3 years of lifeProportion of participants with at least one hospitalisation for bronchiolitis, viral-induced wheeze or asthma in the first 3 years of life using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’.
Prescription for asthma medication in the first 3 years of lifeProportion of participants completing at least one prescription for ICS, SABA, LABA, montelukast in the first 3 years of life, by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection’.
Eczema at 3 years of ageThe proportion of participants whose parent/caregiver answers ‘yes’ to the questions ‘In the last year, has your child had an itchy skin condition—by itchy, we mean scratching or rubbing the skin?’ and IF YES ‘Has this skin condition ever affected the skin creases in the past—by skin creases we mean fronts of elbows, behind the knees, fronts of ankles, around the neck or around the eyes?’ using the UK Diagnostic Criteria for Eczema Questionnaire.32
Hospitalisation for eczema in the first 3 years of lifeProportion of participants with at least one hospitalisation for eczema in the first 3 years of life using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’.
Prescription for eczema medications in the first 3 years of lifeProportion of participants completing at least one prescription for topical steroids in the first 3 years of life by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection’.
Atopy at 3 years of ageThe proportion of participants whose parent/caregiver answers ‘yes’ to the question ‘Has your child had wheezing or whistling in the chest in the past 12 months?’ using the ISAAC Phase III Core Questionnaire for Asthma for children 6–7 years old.16
AND/OR
‘yes’ to the questions ‘In the last year, has your child had an itchy skin condition—by itchy, we mean scratching or rubbing the skin?’ and IF YES ‘Has this skin condition ever affected the skin creases in the past—by skin creases we mean fronts of elbows, behind the knees, fronts of ankles, around the neck or around the eyes?’ using the UK Diagnostic Criteria for Eczema Questionnaire,32
AND/OR
‘yes’ to the questions ‘In the past 12 months, has your child had a problem with sneezing, or a runny, or blocked nose when he/she DID NOT have a cold or the influenza?’ and IF YES ‘In the past 12 months, has this nose problem been accompanied by itchy-watery eyes?’ using the ISAAC Phase III Core Questionnaire for Rhinitis for children 6–7 years old.16
Outcomes to be measured at mid-childhood (at 6 years of age)
Hospitalisation for bronchiolitis, viral-induced wheeze or asthma in the first 6 years of lifeProportion of participants with at least one hospitalisation for bronchiolitis, viral-induced wheeze or asthma in the first 6 years of life using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’.
Prescription for asthma medication in the first 6 years of lifeProportion of participants completing at least one prescription for ICS, SABA, LABA, montelukast or monoclonal antibodies for the treatment of asthma in the first 6 years of life by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection’.
Eczema at 6 years of ageThe proportion of participants whose parent/caregiver answers ‘yes’ to the questions ‘In the last year, has your child had an itchy skin condition—by itchy, we mean scratching or rubbing the skin?” and IF YES ‘Has this skin condition ever affected the skin creases in the past—by skin creases we mean fronts of elbows, behind the knees, fronts of ankles, around the neck or around the eyes?’ using the UK Diagnostic Criteria for Eczema Questionnaire.32
Hospitalisation for eczema in the first 6 years of lifeProportion of participants with at least one hospitalisation for eczema in the first 6 years of life using ICD-10 codes31 and querying the New Zealand Ministry of Health datasets: ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’.
Prescription for eczema medications in the first 6 years of lifeProportion of participants completing at least one prescription for topical steroids in the first 6 years of life by querying the New Zealand Ministry of Health dataset: ‘Pharmaceutical Collection’.
Atopy at 6 years of ageThe proportion of participants whose parent/caregiver answers ‘yes’ to the question ‘Has your child had wheezing or whistling in the chest in the past 12 months?’ using the ISAAC Phase III Core Questionnaire for Asthma for children 6–7 years old,16
AND/OR
‘yes’ to the questions ‘In the last year, has your child had an itchy skin condition—by itchy, we mean scratching or rubbing the skin?’ and IF YES ‘Has this skin condition ever affected the skin creases in the past—by skin creases we mean fronts of elbows, behind the knees, fronts of ankles, around the neck or around the eyes?’ using the UK Diagnostic Criteria for Eczema Questionnaire,32
AND/OR
‘yes’ to the questions ‘In the past 12 months, has your child had a problem with sneezing, or a runny, or blocked nose when he/she DID NOT have a cold or the influenza?’ and IF YES ‘In the past 12 months, has this nose problem been accompanied by itchy-watery eyes?’ using the ISAAC Phase III Core Questionnaire for Rhinitis for children 6–7 years old.16
  • The New Zealand Ministry of Health ‘National Non-Admitted Patient Collection’ and ‘National Minimum Dataset’ provide information based on ICD-10 codes for all interactions an individual has with the public healthcare system outside of primary care including emergency department visits, secondary care outpatient visits and inpatient admissions. These interactions are coded using a unique number known as the National Health Index. As New Zealand has a universal public healthcare system, all such interactions are accounted for. The New Zealand Ministry of Health ‘Pharmaceutical Collection’ records all prescriptions of pharmaceuticals filled by an individual based on their National Health Index number, from both primary and secondary care.

  • ICD-10, International Statistical Classification of Diseases and Related Health Problems 10th Revision; ICS, inhaled corticosteroid; ISAAC, International Study of Asthma and Allergy in Children; LABA, long-acting beta agonist; SABA, short-acting beta agonist.