Appendix A: Factors associated with Staphylococcus aureus colonization

Factors	Group		Total participants (n)	Carriers of S. aureus (n’)	Carriers of S. aureus (%)
Gender	1	• Male	74	7	9.5
		• Female	80	9	11.2
	2	• Male	22	4	18.2
		• Female	29	3	10.3
	Both	• Male	96	11	11.5
		• Female	109	12	11.0
Taking antibiotic during last 2 months	1	• Yes	31	3	9.7
		• No	123	13	10.6
	2	• Yes	8	0	0
		• No	43	7	16.3
	Both	• Yes	39	3	7.7
		• No	166	20	12.1
Smoking	1	• Yes	13	0	0
		• No	141	16	11.4
	2	• Yes	12	3	25.0
		• No	39	4	10.3
	Both	• Yes	25	3	12.0
		• No	180	20	11.1
Using nasal spray	1	• Yes	9	1	11.1
		• No	145	15	10.3
	2	• Yes	4	0	0
		• No	47	7	14.9
	Both	• Yes	13	1	7.7
		• No	192	22	11.5
Nasal wash (by water)	1	• Yes	37	5	13.5
		• No	117	11	9.4
	2	• Yes	10	0	0
		• No	41	7	17.1
	Both	• Yes	47	5	10.6
		• No	158	18	11.4
Acne	1	• Yes	24	2	8.3
		• No	130	14	10.8
	2	• Yes	0	0	n/a
		• No	51	7	13.7
	Both	• Yes	24	2	8.3
		• No	181	21	11.6
Nose conditions (Sinusitis, asthma)(†)	1	• Yes	11	4	36.4
		• No	143	12	8.4
	2	• Yes	8	0	0
		• No	43	7	16.3
	Both	• Yes	19	4	21.1
		• No	186	19	10.2
Body Mass Index (BMI, kg/m2)(‡)	1	• Underweight  ○ (< 18.5 kg/m2)	22	2	9.1
		• Normal range  ○ (18.5 – 23.0 kg/m2)	98	11	11.2
		• Overweight  ○ (≥ 23.0 kg/m2)	34	3	8.8
	2	• Underweight  ○ (< 18.5 kg/m2)	8	0	0
		• Normal range  ○ (18.5 – 23.0 kg/m2)	28	4	14.3
		• Overweight  ○ (≥ 23.0 kg/m2)	15	3	20.0
	Both	• Underweight  ○ (< 18.5 kg/m2)	30	2	6.7
		• Normal range  ○ (18.5 – 23.0 kg/m2)	126	15	11.9
		• Overweight  ○ (≥ 23.0 kg/m2)	49	6	12.2
Total			205	23	11.2

There was only one case suffering asthma.
BMI is calculated via weight (in kilograms) over height squared (in centimeters), applied for Asian people (WHO, 2004).