All 56 children included in the research and their parents were informed about the complete study protocol by letter and subsequently were contacted by telephone.
Of these, 142 (15.6%) were subsequently unable to be contacted, 61 (7%) were later unwilling to participate and 337 (37%) did not meet the eligibility criteria.
This left 1890 mothers of whom 65 subsequently could not be contacted by the research team.
Six were excluded due to language difficulties; four refused; three agreed but on further discussion were not eligible, and one agreed but subsequently could not be contacted.
Subsequently they will be contacted by the Research Assistant and if they agree to take part, written informed consent will be obtained.
If final outcomes were pending when the form was submitted, participating veterinary surgeons could provide details if they wished to be contacted subsequently for further information.
Some participants, although they had consented to take part, had to be excluded from the study, as they could not be contacted subsequently due to unavailability.
Twelve respondents (3.7%) could not be contacted subsequently and 26 (8.0%) had no evidence of pneumonia in the radiologist's report, leaving 79 (24.3%) eligible participants.
6 participants who gave verbal consent to be contacted, subsequently chose not to go ahead with an interview and were not included in the study (4 from the 'at risk' group, and 2 who had been diagnosed).
Members of particular professional groups or clinical sub-specialities may have different attitudes towards research participation, and this may in turn influence the types of survivors who are permitted to be contacted and who subsequently participate in the study [ 32, 36].
