Table 3. Quantitative recovery of bacteria from swabs according to work experience.

Workingexperience	n	Recovery	Mean CFU beforetraining	95%-CI	Mean CFU aftertraining	95%-CI	p-value(Wilcoxon test)
<2 years	133	total bacteria	45.0	[28.1;61.9]	164.0	[129.8;198.2]	p<0.001
		S. aureus	17.5	[10.5;24.5]	65.4	[49.7;81.2]	p<0.001
		S. epidermidis	27.5	[17.4;37.7]	98.6	[78.5;118.6]	p<0.001
2–5 years	46	total bacteria	65.9	[18.7;113.1]	164.4	[103.7;225.1]	p<0.001
		S. aureus	28.4	[7.2;49.5]	68.2	[35.2;101.2]	p<0.001
		S. epidermidis	37.6	[10.9;64.2]	96.2	[66.0;126.4]	p<0.001
5–10 years	21	total bacteria	19.1	[0.0;40.5]	153.2	[54.0;252.5]	p<0.01
		S. aureus	5.1	[0.1;10.2]	50.4	[5.4;95.4]	p<0.01
		S. epidermidis	14.0	[0.0;30.3]	102.9	[45.4;160.3]	p<0.01
>10 years	164	total bacteria	48.0	[31.6;64.5]	152.2	[118.8;185.5]	p<0.001
		S. aureus	20.5	[13.0;28.0]	57.7	[42.4;73.1]	p<0.001
		S. epidermidis	27.7	[18.3;37.0]	94.4	[75.1;113.8]	p<0.001

CFU = colony forming units; 95%-CI = 95% confidence interval.