Table 3.

Results from the logistic regression model of risk factors for gastrointestinal illness in Birkebeinerrittet participants in Norway in 2010

	aOR	95% CI	P value
Cycling in Friday's race	(ref.)
Cycling in Saturday's race	2·72	(2·02–3·67)	<0·001
No mud in the mouth	(ref.)
Mud in the mouth	1·59	(1·28–1·97)	<0·001
Not spitting out the first sip of the bottle	(ref.)
Spitting out the first sip of the bottle	1·56	(1·30–1·88)	<0·001
Having a front mudguard	(ref.)
Not having a front mudguard	1·47	(1·20–1·80)	<0·001
Age >50 years	(ref.)
Age 35–50 years	1·37	(1·06–1·78)	0·113
Age <35 years	1·91	(1·43–2·55)	0·004
Starting between 07:00 and 9:59 hours	(ref.)
Starting between 10:00 and 12:59 hours	0·79	(0·66–0·94)	0·010
Starting between 13:00 and 15:59 hours	0·57	(0·39–0·84)	0·004

aOR, Adjusted odds ratio; CI, confidence interval, ref., reference group (OR = 1).