Clinical assessment
cough, wheezing
One day prior to the clinical assessment, a researcher contacted the family to ensure that the infant was well and did not have any respiratory symptoms (blocked nose, runny nose, wheezing, cough or any other respiratory symptoms) in the two weeks prior to the appointment. Infants were assessed for respiratory health by questionnaire, eNO measurement, physical examination and growth parameters (length, weight, head circumference) by a paediatrician or paediatric nurse between March 2015 and December 2019.