Table 3.

Antibiotic usage according to parental report and prescription data in the 4 weeks prior to the visit.

Antibiotic variablea	Visit	Wheezers N = 26	Non-wheezers N = 72	p-values
Antibiotics in the 4 weeks prior to visit	6 weeks	1 (4%)	7 (10%)	0∙677
	6 months	1 (4%)	2 (3%)	1∙000
	9 months	5 (19%)	6 (8%)	0∙154
	12 months	8 (31%)	3 (4%)	0∙001
	18 months	1 (4%)	7 (10%)	0∙677
	24 months	1 (4%)	6 (8%)	0∙671
Combined antibiotics within a month medical and parental report	6 weeks	1 (4%)	7 (10%)	0∙677
	6 months	1 (4%)	2 (3%)	1∙000
	9 months	7 (27%)	6 (8%)	0∙037
	12 months	8 (31%)	3 (4%)	0∙001
	18 months	1 (4%)	7 (10%)	0∙677
	24 months	3 (12%)	6 (8%)	0∙696
Antibiotics prescription within month of visit	6 weeks	1 (4%)	7 (10%)	0∙677
	6 months	1 (4%)	1 (1%)	1∙000
	9 months	7 (27%)	3 (4%)	0∙003
	12 months	7 (27%)	1 (1%)	<0∙001
	18 months	1 (4%)	3 (4%)	1∙000
	24 months	2 (8%)	4 (6%)	0∙654

The combined variable represents the antibiotic usage according to both parental report and prescription data. Fisher's Exact was used to assess differences in proportions. Bold indicates p value < 0.05.

^aThere are three different variables for antibiotic use each with its own merits. The variable antibiotics in the 4 weeks prior to visit is according to parental report. This variable will thus not include situations where the GP has prescribed antibiotics but these are not subsequently given. For example, the case of a delayed script for an upper respiratory tract infection in case of persistence of symptoms. It will include antibiotics given by other providers for example dentists, or out of hour services which may not have been included in the GP notes or antibiotics given abroad. The antibiotics prescription within a month of visit was derived from prescriptions within the GP notes. The combined antibiotics within a month includes both the courses reported by the parent and those from the GP notes and is the most comprehensive account of antibiotic use.