BMC Public Health 2009, 9:207 http://www.biomedcentral.com/1471-2458/9/207 discomfort, and anxiety or depression and using three levels of severity: no problem, moderate and severe. This scale has been tested on a number of patient groups[32,33]. Respondents are then asked about their smoking and drinking habits and their use of health facilities. Finally they are asked to report their own height and weight to allow us to calculate their Body Mass Index (BMI) and their waist measurement for which we provide a tape measure. Self reported BMI has been shown to have rea- sonable accuracy as an estimate of true BMI [34,35] and waist circumference is the best simple anthropometric measure of total body fat, is better than BMI in that regard [36] and is also the best simple indicator of intra-abdom- inal fat mass [37-40]. Adolescent survey The aim of the adolescent survey is to examine the impact of the initiatives during the critical period of life when children/adolescents develop their health behaviours and habits. We assess levels of psychological and physical health as well as collect data on psychosocial risk factors in adolescents known to be predictive of poor outcomes, including social networks, family factors, peer relations and self esteem. Because of the ethical considerations raised by fieldwork- ers interviewing minors in their homes, we use a school- based, self-report approach for this part of the study. Data from the Department of Schools Children and Families' (DSCF) school surveys and census data suggest that on average each LSOA contains 120 school pupils aged 11– 16. We aim to recruit sixty resident adolescents in each cluster attending schools in and around the borough. Any school with more than 10 pupils from an LSOA were iden- tified using DCSF annual school survey data and con- tacted. LSOA resident children may also be attending schools outside their home Borough. Initial estimates based on DCSF data suggest this survey may require the cooperation of up to 150 schools. We attempt to recruit equal numbers of boys and girls with an even age spread from ages 11 to 16 (years 6–11). We gain appropriate written informed consent. Children then are given a self-administered questionnaire in a class- room situation under the supervision of a researcher and teacher. The questionnaire maps onto the same six domains as the adult survey. However as this survey is a self report survey with an adolescent group who may be as young as 11, we intend only to use measures that have been specifically designed and validated for use with chil- dren and adolescents. The survey covers the child's family demographics; aspects of physical and sedentary activity; psychological wellbeing; attitudes to school and the social and physical environment; artistic activities and levels of health and health behaviours. Demographic questions have been adapted from previous adolescent health surveys [41,42]. Physical activity is assessed with the Physical Activity Questionnaire (Adoles- cent version) PAQ-A. This is a 7-day recall questionnaire of the extent to which children engage in vigorous physi- cal activities. The PAQ-A has good validity compared to other recall measures[43,44]. We also incorporate ques- tions on health behaviours from the WHO/HBSC surveys of adolescent health across Europe [45]. To measure different aspects of psychological wellbeing and social support we use five standardised scales. The ten item Rosenberg Self-Esteem Scale assesses the well-estab- lished relationship between self-esteem and psychological wellbeing (e.g., depression, social anxiety, loneliness, alienation; see Blascovich [46]). Extensive and acceptable reliability (internal consistency and test-retest) and valid- ity (convergent and discriminant) information exists for this scale. We also use the five item Satisfaction With Life Scale (SWLS) to look at general life satisfaction [47], a construct that is independent of self esteem. Pavot [48] provides an extensive list of studies that have used the SWLS with cor- responding normative data. The SWLS has been found to be positively associated with measures of adult subjective wellbeing and negatively associated with measures of psy- chopathology [47]. We also use the strengths and difficulties questionnaire (SDQ). The SDQ is a valid and reliable measure of adjust- ment and psychopathology in children and adoles- cents[49] The SDQ has been used to screen for psychiatric disorders in community samples of children as part of clinical assessment, as a treatment-outcome measure and as a research tool [50-52]. The SDQ correlates highly with teacher/parent reports and with the Child Behaviour Checklist, is sensitive in detecting inattention and hyper- activity and effective in detecting internalising and exter- nalising problems [53]. The survey also employs the PANAS (Positive and Nega- tive Affect Schedule) to assess levels of positive and nega- tive dispositional dimensions. It is predictive of tendencies towards anxiety and depression and is based on the tripartite theory of mental health [54]. Studies have shown the scales to be stable, highly internally consistent and largely uncorrelated [55]. We will use the Multidimensional Scale of Perceived Social Support (MSPSS) [56] to assesses the presence and use of social support networks available to the children. Low levels of social support leaves children at greater risk of negative psychosocial outcomes. Page 6 of 11 (page number not for citation purposes)