The aim of this study is to investigate whether an incentive scheme is a feasible approach to increase walking/cycling to school.

This will be a feasibility study using a two-arm cluster randomised controlled design; the Year 5 group (and respective school) will be the unit of randomisation. Participants will be Year 5 pupils, aged 9-10.

Data will be collected throughout approximately three months. In total, assessments will be carried out over a nine week period, which excludes an interval week between baseline and the first intervention week, and half-term (school holidays).

All children in Year 5's in the selected schools will be approached to participate and will be allocated randomly (according to the school they attend) to the two arms: (i) intervention group taking part in the incentive scheme and (ii) control group receiving ongoing curricular advice on active travel.

Parents' participation consists in completing a socio-demographic questionnaire and consent form, and in completing a daily form (or answering daily text messages) reporting whether child has actively traveled to school (AST report) .

A number of schools will be invited to participate by email. A reply by post, phone or email to the lead researcher will be requested within two weeks, at the end of which pending schools will be contacted by phone to confirm their decision. Of those interested, two schools will be selected, ideally matched for characteristics such as location, free school meals and AST rates.

Once the two participating schools have been identified, a meeting in person will be arranged with each head teacher at a time/place of their choice.

The researcher will then visit the schools and introduce the RIGHT TRACKS study to the Year 5 class. After the study has been presented and questions answered, an information pack will be sent home in the pupil's school folder. This pack will include an information leaflet for child, an information leaflet for the parent/carer, a parent questionnaire, a participant information sheet and a consent form. Two of the points stressed are confidentiality and the freedom to drop out of the study at any time without giving justification. After reading and having the chance of asking questions (by phone/email to the lead researcher), parents will be required to formally consent (opt in procedure) to their and to their child's participation.

Parental questionnaires and consent forms are expected to be filled in at home but phone or email inquiries may be made to the researcher during working hours. Within one week after delivery, parents will be requested to return completed and signed documents to the researcher. Specific methods of distribution and collection will be decided with the school beforehand to accommodate local circumstances and preferences.

Questionnaire completion will be requested of parents, however only return of the signed consent form will be essential to determine the child's participation. In addition, participating children will complete an assent form in the classroom.

Baseline assessment Following the identification of participants, children in both schools will be given and instructed to wear an accelerometer on a waist band above the lateral hip over the ensuing seven days, from the moment they get up until they go to bed, except for water-based activities and certain sports.

Together with the accelerometer, the child will be given the parent AST report form, which he/she must take home and return at the end of the seven day period, completed by the parent, together with the accelerometer. Four questions will be asked to parents in the parent AST report form, in relation to each day of the week: e.g. "On Monday did your child walk or cycle to school, all or part of the journey?", "At what time did your child leave home?", "At what time did your child arrive at school?", "Did your child stop anywhere on the way? If yes, how long was the stop for? ____ minutes".

Upon collection of the accelerometer and completed parents AST report forms, children's AST form will be filled out in the classroom retrospectively in relation to the five previous school days (mornings). The only question to be asked to children in relation to the five days is: e.g. "On Monday did you walk or cycle to school, all or part of the journey?" At the end of the baseline week, those complying with the study protocol will be rewarded, as stated in advance on the information materials: a prompt return of the completed parent AST report form and undamaged accelerometer, and completed child AST report form in the classroom, will be essential requisites for receiving a £5 thank you voucher.

Intervention phase The next stage of the RIGHT TRACKS consists in testing the feasibility of the incentive scheme. Similar to baseline, the quality of data from the three sources - accelerometry, parental AST report and child self-report of AST - will be examined. In particular, the validity of parental and child-reported AST will be assessed vis-à-vis accelerometry, currently considered to be one of the gold-standards. However, parental report of AST will be used as the basis of the incentive scheme. Once again, in both intervention and control conditions, there will be a £5 thanks voucher for every child taking part in the measurement procedures, in compliance with the protocol. At the end of the study, a debrief sheet will be handed to all participants, including parents and children, and to the two head teachers.

Intervention group - incentive scheme The incentive scheme will be explained to the intervention group in an introductory session. Partway active trips will be given particular emphasis. Each subsequent session is anticipated to take no more than 25 minutes per week of the classroom time.

The incentive scheme run in the intervention school consists of a prize draw taking place once a week. The prize is a £5 shopping gift voucher valid in a number of high street shops. Chances of winning depend entirely on the number of "points": the number of active trips to school reported exclusively by the parent on the AST report form, through the same questions used at baseline. For each week day that they travel to school the child gets one point. This point is the equivalent to a ticket with the child's ID number that will then be entering the draw. Each child can earn between zero and five tickets per week, depending on the number of active travel trips to school reported by the parent. Discrepant numbers between parental reports and those reported by the child or recorded on the accelerometer are of great interest for measurement, but will be disregarded for the purposes of the draw. In the absence of the parent AST report, the child report may be use for point count, but the child will be reminded that the parental report will be necessary for the next draw.

A difference between baseline and intervention phase concerns the format of the parent AST report form, which may now be completed in writing as before, or by SMS text messages on the weeks the child is not wearing the accelerometer. Preference for either of the options can be stated in advance in the consent form. Parents will be asked to keep them, fill in and return on time every week (personally or via the child), as the programme proceeds. Mobile phone respondents will be notified daily by SMS, to which they can reply directly. Questions asked will be the same in the paper version and mobile phone. However, on the two weeks the child wears the accelerometer, all participants will be asked to use the parent AST report. When the child is not wearing the accelerometer, the only question asked on the parental form or text messages is whether the child walked/cycled to school all or part of the journey. For those wearing the accelerometer in the intervention school, the point will be credited as long as the first question is answered (i.e. if parent indicated whether child actively traveled but failed to complete questions on times).

During the intervention phase, three tasks will be expected from children: (1) wearing an accelerometer for another seven-day period, which they must return to the classroom, together with the parent AST report form, (2) returning the parent AST report form in the remaining weeks (if applicable) and (3) complete an AST report form in the classroom each day of the draw.

Thank you vouchers (£5) will be issued on timely receipt of the accelerometer (together with AST forms), even if the accelerometer turns out to not have been worn for the requested time (i.e. at least four days, including at least one weekend day, and 10 hours each day).

The researcher will retire to a different room (or section of the school) and based on the parent AST report form only, points relative to the five previous days will be calculated. In the case of SMS, responses will be gathered in the evening, at the researcher's workplace, and next day's point will only be credited if received before 12noon (this will be stated in every text message that parents receive on a draw day). Class scores will be anonymously displayed on a graphic/chart week-after-week, in a printed version if possible or by hand if necessary. Depending on the school's preferences and availability, the logistics of counting points and producing tickets may be slightly different. For example, a teacher may agree to return all the completed parent AST reports to the school office in the morning, in which case the researcher could collect them and prepare the tickets in advance.

After producing all the tickets, the researcher will return to the classroom to distribute the accelerometers to the next batch of users. Once the thank you vouchers and accelerometers have been sorted out, the draw will finally take place in the classroom. A ticket will be picked out of a black string bag, probably by a school staff member of by the researcher. Depending on parental choice specified on the consent form, the incentive scheme voucher will be provided to the winner straight away, or will be left in the school office for later collection by the parent. The class score graphic/chart will be put on display on the wall.

Control group - normal curricular AST advice With the exception of the incentive scheme, identical procedures will be followed in both intervention and control groups. Each week, new groups of participants (e.g. the next five on the list) will be requested to wear the accelerometer, return the parent AST report form (if applicable) and complete their own AST report form.

Qualitative study One component of this study consists of semi-structured interviews with children, parents/carers and stakeholders, both from experimental and control groups, to explore different perspectives associated with the proposed intervention and trial procedures and to help refine both. Willingness to be interviewed will be expressed in the consent form before baseline in the case of parents (in addition to assent form in the case of children), from which a purposive sample will be selected based on the socio-demographic variables assessed in the questionnaire. The researcher will directly invite teachers and head teachers, who in turn will suggest other stakeholders for interview among their acquaintances (snowball sampling).

The aim will be to interview dropout participants throughout the intervention phase (as soon as they leave the study), and full participants immediately after the study has ended (January 2015). Sessions are expected to last between 30-45 minutes for adults and 15-30 minutes for children. Verbal consent to take part and to have the session audio-taped will be requested at the onset (in the case of children, to parents first and then by verbal assent), and the confidential nature of all records will be reiterated. Data will be securely stored in compliance with Newcastle University's regulations.

Inclusion Criteria:

• Year 5 children in any of the selected schools
• Consent from parent and assent from child

Exclusion Criteria:

• No consent/assent

Serious and Other (Not Including Serious) Adverse Events were not collected/assessed

• Few resources available to recruit schools and families
• Small sample size
• Small number of non-ATS trips with MVPA data
• The same person delivered the intervention, collected and analysed the data