Table 1

Multiple risk behaviours and their derivation

Health risk behaviourDefinition/how derived
Physical inactivityYoung person (YP) has typically over the past year exercised <5 times per week.
TV viewingYP spent 3 or more hours watching TV on average per day across the week.
Car passenger riskYP had been in a car passenger at least once in their lifetime where the driver (1) had consumed alcohol or (2) did not have a valid licence, or (3) the YP chose not to wear a seat belt last time travelled in a car, van or taxi.
Cycle helmet useIf the YP reported that they had last ridden a bicycle within the previous 4 weeks and they had not worn a helmet on the most recent occasion.
Scooter riskYP has driven a motorbike/scooter off road, or without a licence on a public road at least once.
Criminal/antisocial behaviourYP reported that at least once in the past year they had undertaken at least one of the following seven offences: carried a weapon; physically hurt someone on purpose; stolen something; sold illicit substances to another person; damaged property belonging to someone else either by using graffiti, setting fire to it or destroying or damaging it in another fashion; subjected someone to verbal or physical racial abuse; or been rude/rowdy in a public place.
Hazardous alcohol consumptionIn the past year had scored 8 or more on the Alcohol Use Disorders Identification Test indicating hazardous alcohol consumption.
Regular tobacco smokingHas ever smoked and is regularly smoking by currently smoking at least one cigarette per week.
Cannabis useThose who reported using cannabis ‘sometimes but less often than once a week’ or more regular use were classified as occasional users.
Illicit drug/solvent useIn the year since their 15th birthday, YP had either been a regular user (ie, used five or more times) of one or more illicit drugs (excluding cannabis) including amphetamines, ecstasy, lysergic acid diethylamide (LSD), cocaine, ketamine or inhalants including aerosols, gas, solvents and poppers.
Self-harmYoung people who said they had purposely hurt themselves in some way in their lifetime.
Penetrative sex before age 16YP reported having had penetrative sex in the preceding year and that they were under 16 at the time.
Unprotected sexPenetrative sex without the use of contraception on the last occasion they had had sex in the past year.
  • Sources of information:

  • Age 15 years clinic: criminal and antisocial behaviour, penetrative sex prior to age 16, and unprotected sex.

  • Age 16 years questionnaire: physical inactivity, TV viewing, car passenger risk, cycle helmet use, scooter risk, hazardous alcohol drinking, regular smoking, illicit drug/solvent use and self-harm.

  • TV, television.