Table 1

Baseline characteristics of students

Characteristic

Exposure ad

(N = 205)

Neutral ad

(N = 192)

P-value


Age, mean (SD)

14.0 (1.4)

14.1 (1.7)

0.86*

Male, n (%)

83 (40.5)

76 (39.6)

0.85

Grade, n (%)

7

54 (26.3)

56 (29.2)

0.43

8

47 (22.9)

44 (22.9)

9

60 (29.3)

50 (26.0)

10

23 (11.2)

14 (7.3)

11

21 (10.2)

28 (14.6)

Family affluence score, mean (SD)

5.5 (1.2)

5.4 (1.2)

0.19*

Smoking status, n (%)

Nonsusceptible never smoker

119 (58.6)

96 (50.5)

0.30

Susceptible never smoker

30 (14.8)

40 (21.1)

Experimenter

43 (21.2)

41 (21.6)

Established smoker

11 (5.4)

13 (6.8)

Ice hockey fan, n (%)

Very much

67 (32.8)

64 (33.5)

0.30

A bit

55 (27.0)

60 (31.4)

Not really

47 (23.0)

30 (15.7)

No

35 (17.2)

37 (19.4)

Test time, n (%)

Morning

166 (81.0)

134 (69.8)

0.01

Afternoon

39 (19.0)

58 (30.2)


* P-values are based on the Wilcoxon rank sum test for two variables; all other p-values are based on contingency tables for categorical variables.

† Ranges from 1 to 7

‡ Grade 7 and 8 questionnaires were administered during one class period. Grade 9 to 11 questionnaires were administered either in the morning or afternoon.

Auger et al. BMC Pediatrics 2011 11:26   doi:10.1186/1471-2431-11-26

Open Data