Table 1

Socio-demographic and behavioural characteristics of participants

School Health Research Network survey measures (no. of respondents for ages 11–16/15–16)Years 7–11 (aged 11–16)Year 11 (aged 15–16)
Mean (SD) age (n=32 386)/(n=5353)13.6 (1.4)15.7 (0.3)
Female % (n) (n=31 334)/(n=5373)52.0 (1881)53.4 (2871)
BME % (n) (n=31 614)/(n=5290)11.1 (3521)12.2 (645)
Mean (SD) FAS (n=28 661)/(n=4674)14.9 (2.0)14.9 (2.0)
Ever smoked % (n) (n=30 327)/(n=5001)10.5 (3182)26.5 (1325)
Smoking status % (n)
(n=30 353)/(n=5050)
 Don't94.0 (29 045)84.6 (4276)
 <Weekly1.5 (458)3.9 (197)
 Weekly1.0 (331)2.5 (124)
 Daily2.3 (717)6.3 (320)
 Ex-smoker1.2 (366)2.7 (135)
Ever used an e-cigarette % (n) (n=30 259)/(n=4990)18.5 (5587)37.3 (1860)
Current e-cigarette use % (n) (n=30 917)/(n=5060)
 Don't95.6 (29 434)91.0 (4602)
 <Weekly1.8 (542)3.3 (169)
 Weekly1.3 (399)2.4 (121)
 Daily1.4 (423)3.3 (166)
Cannabis ever use % (n) (n=26 858)/(n=4407)5.0 (1332)14.8 (653)
Cannabis use in past month % (n) (n=26 902)/(n=4426)
 Never97.1 (26 141)92.1 (4078)
 Less than daily2.0 (534)5.6 (249)
 Daily0.8 (227)2.2 (99)
Mephedrone ever use % (n) (n=26 763)/(n=4447)1.3 (342)2.6 (117)
Laughing gas ever use % (n) (n=26 772)/(n=4445)27.1 (7258)27.4 (1219)
Alcoholic drinks per session % (n) (n=30 174)/(n=4862)
 None72.0 (21 772)40.1 (1949)
 1–421.6 (6520)39.1 (1902)
 5+6.2 (1882)20.8 (1011)
  • BME, black and minority ethnicity; FAS, Family Affluence Scale.