Table 1.

Outcome measures

Outcome	Collected by	Timing of collection	Source
Primary outcome
Number of absence episodes due to any illness1,2	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
Secondary outcomes
'Follow-up children'
Number of absence episodes due to respiratory illness	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
Number of absence episodes due to gastrointestinal illness	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
Length of illness episode	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
Length of absence episode	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
Number of household members who become ill within one week of the participating child's illness onset	Telephone interview	8 - 9 days after the date of the first day of absence from school	Parents of children
All children
Number of absence episodes for any reason	Liaison research assistant3	Weekly	School roll
Length of absence episode	Liaison research assistant3	Weekly	School roll
Adverse events
Skin reactions1	Telephone interview	Following the intervention period	Parents of children

¹ 'Follow-up children' only.

² Parents will not be telephoned where it is clear that the child was not unwell (for example, on a holiday, attended a funeral, etc).

³ Through contact with school staff or by extracting the data in person.