Table 1.

Variables examined

Variable	Sweep of data collection	Units of analysis
Demographic variables
Sex	First	Male or female
Ethnic Group	First	White, Asian (includes Indian, Pakistani, Bangladeshi and other Asian), African (includes Black Caribbean, Black African, Other Black)
Number in household	First	Number reported
Socio-economic variables
Family Income	First	Per annum: <£10,400, £10,400 - £20,800 >£20,800
Highest academic qualification	First	None, GCSE/O'level, A'level, University degree or higher
Access to car or van	Second	Yes or no
In work	Third	Yes or no
Housing/Area
Good area to raise children	Third	Poor, good or excellent
Area/setting	First and second	Urban, town or village
Type of accommodation	Second and third	House/bungalow or Flat/maisonette
Access to garden	First, second and third	Yes or no
Perceived safety of area	Third	Safe, moderate, unsafe
Parental factors
Age of respondent	Third	Age reported
Respondent general health	Third	Excellent, very good, good, fair or poor
Anyone smoke near child	Third	Yes or no
Child factors
BMI of child	Third	BMI score reported
Parental assessment child behaviour (SDQ)	Third	SDQ score reported
Bracken score	Second	Bracken score reported
Exercise outside school at a club or class	Third	1 = Once a week, 0 = Less than once a week
Walk or cycle to school	Third	Yes or no
Sport with parent	Third	1 = Once a week, 0 = Less than once a week
Plays physically active games with parent	Third	1 = Once a week, 0 = Less than once a week
Go to playground with parent	Third	1 = Once a week, 0 = Less than once a week
Hours television watched per day	Third	Less that 3 hours or more than 3 hours