Table 5.

Multinomial logistic regression analysis, with the 12MR score as outcome variable and smoking as the predictor variable.

	Low CRF			Intermediate CRF
	N	OR	95% CI	N	OR	95% CI
Underweight (BMI < 18.5)a
Smoking
No smoking (reference)	18	1.00		24	1.00
Occasional smoking	0	0.08	0.00–0.44	8	0.64	0.18–2.2
Regular smoking	9	1.18	0.32–4.41	34	3.32	1.16–10.3
Normal weight (18.5 ≤ BMI < 25)
Smoking
No smoking (reference)	65	1.00		166	1.00
Occasional smoking	26	0.78	0.48–1.28	131	1.54	1.14–2.09
Regular smoking	74	2.35	1.59–3.48	172	2.14	1.59–2.88
Overweight/obese (BMI ≥ 25)
Smoking
No smoking (reference)	49	1.00		36	1.00
Occasional smoking	19	0.75	0.34–1.66	41	2.21	1.06–4.6
Regular smoking	65	6.25	2.56–15.3	41	5.37	2.12–13.6

The ORs denote odds of belonging to the lowest quintile (low CRF) or to the second or third quintile (intermediate CRF), compared to belonging to the fourth of fifth quintile (high CRF). Separate analyses by BMI.

12MR, Cooper’s 12-minute run test; BMI, body mass index; CI, confidence interval; CRF, cardiorespiratory fitness; N, number of subjects; OR, odds ratio.

^aExact test.