Table 1

Description of the sample and crude associations with smoking

Continuous variablesMedianIQR*Association with smoking
Crudep Value
Categorical variablesn%OR
Smoking status
 Never smoked in last year140671.1
 Ever smoked in last year57228.9
Film-smoking exposure
 Beach method (does not consider times seen)9660–1342.080.001
 Modified Beach method (considers times seen)196120–3142.59<0.0001
Media use/access
 Number of hours watching TV/DVDs on weekdays
  Quartile 1 (0–2 h)61030.5Ref
  Quartile 2 (3 h)32116.11.070.67
  Quartile 3 (4–5 h)38919.51.310.09
  Quartile 4 (6 or more hours)46023.01.320.62
 Has DVD or video player in bedroom
 Has access to the internet/web in bedroom
 Has digital, satellite or cable TV channels
Rules about media
Television/films rules
 Parental approval of what is watched:
  Definitely not/possibly not28514.5Ref
  Don't know34517.61.170.29
  They wouldn't mind944481.060.75
  They would approve39119.91.090.66
 Allowed to watch 18 certificate films
 Has to finish homework/chores before watching TV
 Only allowed to watch a certain amount of TV
 Access to some TV programs restricted
 Allowed to watch anything on TV
 Breaks TV/DVD rules:
  Assume don't have rules about watching TV90547.9Ref
  Yes, I often break them1638.61.130.51
  Yes, I sometimes break them44323.50.3<0.0001
  No, I follow these rules377200.39<0.0001
  TV/films parenting scale from above six variables (α=0.68) (0–6) each one point increase is adding an item10–30.71<0.0001
Film viewing pattern
 Views films with parents (0–4)21–30.43
Internet rules
 Internet access restricted or not
  Don't know33917.1
 Internet usage supervised?
Family background
 Housing tenure
  All other types of accommodation41672.71.460.005
 Parental education:
  Either/only parent remained at school beyond age 1696148.1Ref
  Both/only parent(s) left school at 16 years of age67133.61.520.001
 Family connectedness: (0–8)65–70.35<0.0001
 Parental monitoring: (0–8)64–70.46<0.0001
Individual characteristics
 Number of national school examinations being sat
  6 or less80240.11.78<0.0001
 School leaving plans
  Plans to remain in school beyond statutory leaving age135069.3Ref
  Plans to leave school as soon as legally entitled to36318.73.59<0.0001
  Don't know233121.280.17
Peer behaviours
 Peer smoking (0 none, 4 most/all)12–251.7<0.0001
 Views movies with friends21–23.85<0.0001
  • * Medians and IQR reported for variables in their original form.

  • For this assessment, all ordinal and continuous variables scaled so zero represents lowest risk category and one represents the highest response category.