G184 HOW CAN WE RELIABLY MONITOR THIS EPIDEMIC OF OBESITY? DEVELOPMENT OF A METHODOLOGY

M. C. J. Rudolf¹, R. G. Feltbower¹, R. Levine², A. Connor², M. Robinson².¹Leeds University, Leeds, UK; ²East Leeds PCT, Leeds, UK

Background: Government targets have been set to halt the rise in childhood obesity by the year 2010, but no systems are in place to measure if this is achieved. School monitoring, apart from at school entry, has been discontinued, and routine data are often inaccurate, reported incompletely, or entered erroneously.

Aims: To develop a feasible and cost effective methodology to monitor levels of obesity in school children.

Methods: Ten primary (five inner city, five suburban) and three high schools were selected. Ethics approval was obtained for “opt out” consent. Children in reception, year 4, and year 8 were measured. Data were converted to SD scores and analysed by age, socioeconomic status, and ethnicity. Percentage of obese (BMI >98^thcentile) and overweight (BMI >91^stcentile) children were calculated. Sample size calculations were undertaken to ascertain how many schools would be required to detect an increase in weight of 0.1 BMI SD per year or an increase by 1% in numbers of obese children with 90% power.

Results: A total of 999 children were measured with ascertainment of 95% in primary schools and 85% in high schools. Analysis confirmed the sample was representative of the city with respect to socioeconomic status and ethnicity. Data for each school year showed: mean BMI SD (95% CI) of 0.16 (0.05 to 0.28), 0.38 (0.26 to 0.50), and 0.53 (0.37 to 0.69), respectively; a slight increase over previous local data from 1996–2001; percentage obese 7.1%, 10.3%, and 12.9%, and percentage overweight 14.7%, 21.8%, and 24%. No significant trends were observed for socioeconomic status or ethnicity. Sample size calculations indicated that …