Table 1.

Manipulation of STARWAVe factors in the present study

Factor	Factor levels^a	Factor range
Age	1: <2 years	4 months to 6 years^b
Age	0: ≥2 years	4 months to 6 years^b

Illness duration	1: ≤3 days	1 to 21 days^c
Illness duration	0: >3 days	1 to 21 days^c

Temperature	1: parent reports severe fever in the last 24 h	N/A
Temperature	0: none	N/A

Vomiting	1: parent reports moderate/severe vomiting in the last 24 h	N/A
Vomiting	0: none	N/A

Current asthma	1: present	N/A
Current asthma	0: none	N/A

Inter/subcostal recession	1: present on examination	N/A
Inter/subcostal recession	0: none	N/A

Wheeze	1: present on examination	N/A
Wheeze	0: none	N/A

↵a Factor levels were based on the STARWAVe clinical prediction rule, which assigns 1 point if the patient is: aged <2 years; if illness duration is ≤3 days; if the parent reports severe fever in the last 24 h; if the parent reports moderate or severe vomiting in the last 24 h; if the patient has current asthma; if inter/subcostal recession is present on examination; and if wheeze is present on examination.
↵b Most vignettes (83%) featured children who were aged 1–6 years, which was the interquartile range in the prognostic cohort study that gave rise to STARWAVe. The full range in the STARWAVe cohort study was 3 months to 16 years.
↵c Most vignettes (73%) had an illness duration of 3–10 days, which was the interquartile range in the STARWAVe cohort study. The full range in the STARWAVe cohort study was 0 28 days. N/A = not applicable.