The BRIGHT Trial is a multi-centre, school-based, assessor-blinded, two-arm cluster-randomised controlled trial (RCT).
The population being investigated are pupils in schools with above average percentage of pupils eligible for free school meals (FSM). The BRIGHT intervention is based on the New Zealand KOB study intervention (31). It is a multi-component, complex intervention with two parts; 1) a short classroom-based session (CBS) embedded in the curriculum, and 2) a series of follow-up twice daily SMS. Pupils in the control group will continue to receive routine education and no text messaging, and the primary outcome is the presence of caries.
The trial aims to recruit 5,040 young people, aged 11-13 years (Year 7 and Year 8 England/Wales; S1 and S2 Scotland) from 42 schools across Scotland, England and Wales with above the national average percentage of pupils eligible for FSM. These year groups have been chosen purposefully to minimise disruption to English and Welsh GCSE and Scottish Qualifications Authority National 5 exam years; and also to confine 3-year follow-up to within the school setting to avoid the need to follow participants to Further Education settings.
School eligibility (inclusion/ exclusion criteria)
To be eligible for participation, schools must:
· be located in Scotland, England (South Yorkshire and West Yorkshire), or South Wales
· be state funded;
· have pupils aged 11-16 years old;
· have at least 60 pupils per year group; and
· have above the national average percentage (for each devolved nation) of pupils eligible for FSM.
Schools will be ineligible for inclusion if they are:
· in Special Measures where the school is judged by the Office for Standards in Education, Children's Services and Skills to be failing, or likely to fail, to provide an acceptable standard of education; and
· due to close.
Eligible schools will be identified based on data from the Department for Education's register of educational establishments in England and Wales and Education Scotland. Schools will be approached by local research teams and invited to take part.
Young people, aged 11-13 years old at baseline, attending schools with above the national average percentage of pupils eligible for FSM.
Young person (participant) eligibility (inclusion/ exclusion criteria)
Young people will be eligible for inclusion if they are:
· a pupil at a participating school; and
· aged 11-12 years (in Year 7, England/ Wales and S1 year in Scotland) or 12-13 years (in Year 8 in England/ Wales and S2 Year in Scotland).
Young people will be ineligible for inclusion if:
· they have no functioning mobile telephone of their own; or
· their parent/ carer does not want them to be part of the trial and they opt-out.
Young person (participant) recruitment
Recruitment strategies have been based on consultation with; young people through a youth organisation particularly concerned with hard-to-reach young people - Children and Young People’s Empowerment Project (Chilypep), teachers and head teachers, a school welfare officer and school nurse, and from learning during the internal pilot trial. A young person forum has contributed to the design of the trial and successfully ran throughout the internal pilot trial. This forum will continue to advise on participant recruitment and the best ways of optimising continued engagement with hard-to-reach pupils during the trial.
Parents/carers will have the opportunity to state that they do not want their child to participate (opt-out), by completing and returning an opt-out form to their child’s school. Eligible young people, whose parents/carers have not opted them out of the research, will then be invited to take part in the trial. The young people who agree will be asked to sign a consent form by members of the local research team or teachers.
All young people who complete the baseline questionnaire and dental assessment will be given a £10 voucher to thank them for their time; all young people who complete the final follow-up questionnaire and dental assessment will be given a £5 voucher as a thank you.
Allocation will take place within schools by randomising schools 1:1 to one of two regimes:
1) pupils of 11-12 years (Year 7 in England and Wales/S1 in Scotland) to receive the intervention and pupils of 12-13 years (Year 8 in England and Wales/S2 in Scotland) to act as the control group; or
2) pupils of 12-13 years (Year 8 in England and Wales/S2 in Scotland) to receive the intervention and pupils of 11-12 years (Year 7 in England and Wales/S1 in Scotland) to act as the control group.
An allocation sequence, stratified by school using blocks of size two (32), will be generated by an independent statistician. This sequence will be retained by the statistician and will not be accessible to other members of the trial research team. Once a school is ready to be randomised, following collection of their baseline data, the year groups within that school will be randomised by assigning their Year 7 and Year 8 cohorts (in that order) to the next block in the allocation schedule. The research team and schools will then be informed of which year group has been allocated to receive the BRIGHT intervention, and which has been assigned to the control arm. Since the statistician performing the allocation and the teams recruiting the schools are completely separate, and the allocation schedule cannot be known to anyone but the statistician in advance of randomisation, allocation concealment is assured.
Given the nature of the intervention, it will not be possible to blind schools or participants (pupils) to their group allocation; however, clinical examinations will be performed by a trained and calibrated dentist blind to the allocation of the pupils, as far as possible. It is possible that pupils may unblind the assessors but they will be encouraged not to discuss the intervention with the dental team to minimise this risk. We shall ask the dental teams to record whether they became unblinded to the pupil’s allocation.
Intervention and comparison (control)
The aim of the intervention is to increase toothbrushing frequency with a fluoride toothpaste and thereby reduce the incidence of dental caries. The intervention consists of two components: (1) a CBS delivered by teachers in the schools’ curricula followed by; (2) a series of twice daily SMS to mobile phones. The intervention meets the Medical Research Council definition of a complex intervention in terms of the interactions between components and the difficulty of behaviours required by those receiving the intervention (33). The control group will not receive the CBS or SMS messages. The KOB intervention has been refined to be more acceptable to young people and informed by recent behaviour change theory (34).
Teachers will deliver the single CBS (50 minutes in duration) in the school environment to participants in the intervention arm. The schools will receive a teacher’s guide that will outline the learning intentions and success criteria for the lesson, in addition to the appropriate teaching resources in order to deliver the lesson. The lesson has been quality assured in England, Scotland and Wales. The number of schools that report delivering the classroom-based session will be reported.
The schedule of SMS was developed using young people’s own words and will reinforce the messages from the CBS. SMS will be provided via mobile phones twice daily according to the recommended frequency of toothbrushing (35) with a fluoride toothpaste. Participants will be reminded to inform the study team of any changes to their mobile phone number. When participants wish to stop receiving text messages, they can text STOP for free at any time. Messages will also be re-started on request. The number of SMS messages received by the pupils will be summarised descriptively.
The primary outcome is the presence of (treated or untreated) carious lesions in permanent teeth, measured using DMFT where decay is measured as caries into dentine - International Caries Detection and Assessment System ([ICDAS] levels 4-6) (36). Caries will be assessed during clinical assessments at baseline and the end of years 2 and 3. The primary outcome assessment time point will be 3 years.
· Caries (D4-6 MFT) at 2 years: The presence of carious lesions in permanent teeth ([ICDAS] levels 4-6) at 2 years follow-up.
· Caries (D1-3 MFT) at 3 years: The presence of carious lesions in permanent teeth ([ICDAS] levels 1-3) at 3 years follow-up.
· Twice-daily toothbrushing: Self-reported toothbrushing frequency using validated questions from the national Child Dental Health surveys at baseline, 6 months, 1, 2 and 3 years. To validate the self-reported measure, two proxy clinical objective indicators will be collected: (i) clinically assessed plaque levels using Turesky’s modification of the Quigley Hein Plaque Index (37, 38); and (ii) clinically assessed gingivitis using gingival bleeding (modification of the Gingival Index of Löe) (39) and mean number of bleeding gingival sites per child. The clinical measures will be carried out at baseline and at the end of years 2 and 3.
· Health related quality of life (HRQoL): will be assessed using the Child Health Utility 9D (CHU9D) (40). This will be measured at baseline, and at years 1, 2, and 3.
· Child oral HRQoL: will be assessed using the CARIES-QC. This will be measured at baseline, and at years 1, 2, and 3.
Oral health behaviours: will be assessed based on self-reported data from young people using questions from the national Child Dental Health Survey (4, 41) on diet, use of dental services and other forms of fluoride use which will allow assessment of confounding. This will be measured at baseline, 6 months, and at years 1, 2, and 3.
Cost-effectiveness: health service resource use will be assessed for the health economic analysis based on data reported by parents via a questionnaire. This will be measured at baseline, and at years 1, 2, and 3. Resource use may also be estimated from routine data sources.
School attendance: impact on school attendance will be measured by asking schools to provide the attendance record of all participating young people at baseline and at 1, 2, and 3 years.
Social deprivation: The impact of the intervention on young people from deprived areas specifically will be assessed. Young people’s eligibility for FSM will be collected from their school and Income Deprivation Affecting Children Index (IDACI) scores will be calculated where possible from participant’s home postcodes.
Process evaluation: a mixed method process evaluation will also be conducted to explore implementation, mechanisms of impact and context of the complex intervention (42).
Figure 1 describes the schedule of recruitment, assessments and intervention delivery.
Data collection will be carried out in the secondary schools under standard dental epidemiological conditions and with questionnaires completed by young people in school time and by parents at home.
The University of Dundee and York Trials Unit (YTU) at University of York will act as the data controllers for this study. All information collected during the course of the trial will be kept strictly confidential. YTU and the regional sites will comply with all aspects of the General Data Protection Regulation 2016 applicable in the UK from May 2018. Personal data will be processed under Article 6 (1) (e) (Processing necessary for the performance of a task carried out in the public interest) and Special Category data under Article 9 (2) (j) (Processing neccessary for ... scientific ... research purposes) of the General Data Protection Regulation 2016. Data Sharing Agreements will be put in place with participating schools.
A unique trial identification number (Trial ID) will be generated for each participant, details will be entered into the trial management system. All data, from baseline through to final follow-up, will be collected on paper using Case Report Forms (CRFs) and identified solely by the Trial ID, they will be scanned at YTU, using Teleform data capture software, into a bespoke data management system. Both the trial management system and the data management systems are held on secure University of York servers with access limited to specified members of YTU staff. The paper consent forms and paper CRFs will be held separately and securely in controlled access area in locked cabinets.
The young person’s mobile phone number, along with their nickname (to which text messages will be addressed) and text message time preference will be uploaded by YTU directly to the Health Informatics Centre (HIC), University of Dundee. No other details will be uploaded. HIC Services operates a secure Safe Haven environment with strong data governance for the provisioning of data.
The estimated proportion of UK 12 year olds with caries is 32%, with estimates of 46% for those eligible for FSM and 30% for those not eligible for FSM (4, 43). Based on a systematic review of interventions for caries prevention to increase the frequency of toothbrushing, (44) an absolute reduction in the proportion of young people with caries of 8% might be expected with this intervention. An individually randomised trial powered at 90% (5% two-sided α) to detect a reduction in the proportion of young people with caries from 32% to 24% would require a sample size of 1,320. Since this is a cluster trial, this figure needs to be inflated to account for the correlation of the outcomes within schools, as measured by the intraclass correlation coefficient (ICC). Few estimates of a school-level ICC are available for dental data. In a previous study evaluating a behaviour change programme for preventing dental caries in primary schools, an ICC of 0.01 was used which was estimated using their own unpublished data (45); a more conservative ICC of 0.02 has been chosen for this trial.
Additionally, since randomisation is taking place at the level of the year group, and not at the school-level, there is the potential for some contamination (e.g. pupils in the year group assigned to the control arm receiving information about the intervention from pupils in the other participating year group assigned to receive the intervention). There is an argument to therefore increase the sample size further to account for some level of contamination, which has the potential to dilute the treatment effect. We have assumed only partial contamination effects (i.e. those contaminated gain half the treatment benefits, as it is unlikely that any pupil in the control group would receive all the intervention) for 27% of the control group pupils (based on findings from the internal pilot phase on the trial). In total, 40 schools are required assuming within-school (year group level randomisation), an average of 60 pupils per year group, an ICC of 0.02, and 20% pupil-level attrition at follow-up. This would give us 90% power (5% two-sided α) to detect an 8% absolute reduction, from 32% to 24%, in the proportion of pupils with caries. An attrition rate of 20% was estimated as the pupils will continue to be at school for the duration of the trial so it will be possible to reach and engage with them through the School and in an environment they recognise as educational and supporting their interests. Overall, 42 schools will be recruited to allow for the potential that a small number of schools may withdraw.
All analyses will be conducted on an intention to treat basis, including all randomised young people in the groups to which their year group was allocated irrespective of deviations based on non-compliance, unless otherwise stated. Data from the internal pilot will be used in all analyses.
The primary analysis will compare the proportion of young people with any treated or untreated caries in permanent teeth at 2 and 3 years between the intervention and control groups using a repeated measures binary logistic multilevel model, with the primary time-point of interest at 3 years. The model will control for presence or absence of caries at baseline, year group, time, and an interaction between treatment and time as fixed effect covariates. Pupils and school will be included as random effects (to allow for clustering of data within each pupil (over time) and school). Cohen’s kappa coefficient will be used to measure the intra-examiner agreement of presence of carious lesions at ICDAS code 4-6 for 5% of participants who will be examined twice at a particular time point.
A subgroup analysis will be conducted looking at participants with baseline caries by including presence or absence of caries at baseline in an interaction with treatment group in the primary model. The hypothesis is that young people with caries at baseline are more likely to have caries at follow-up that those who do not have caries at baseline.
Secondary analyses will compare self-reported twice-daily brushing frequency at 6 months, 1, 2 and 3 years using a repeated measures binary logistic multilevel model. Continuous measures (Plaque Index Gingival Index of Löe), mean number of bleeding gingival sites per child, and CARIES-QC will be analysed using a covariance pattern model. Other secondary outcomes will be analysed using appropriate regression techniques.
Health economic assessment
A cost-utility analysis will be conducted. This will estimate the mean differences in costs, Quality Adjusted Life Years (QALYs), and report the incremental cost-effectiveness ratio (ICER) for each pathway. The cost-utility analysis will be conducted in line with current recommendations from NICE. In particular, an NHS and Personal Social Services perspective will be taken for costs, and health benefits will be quantified using QALYs. The longer term cost-effectiveness will be modelled to estimate the longer term resource use and health related quality of life implications of the intervention.
QALYs will be estimated using the CHU9D (40) reported at baseline and annually thereafter. The CHU9D will be valued using published population tariff values (40, 46) allowing QALYs to be estimated for each arm using the trapezium rule to calculate the area under the curve.
NHS resource use will be measured for each participant at baseline and annually up to 36 months. This will include all medication costs (e.g. antibiotics), visits to dental practices for treatment and health services (e.g. referral to specialists in paediatric dentistry, dental admission for a general anaesthetic) using the parent resource use questionnaire.
Serious Adverse Events (SAEs) and Adverse Events (AEs)
All participants in the BRIGHT trial will have a dental assessment and complete questionnaires throughout the study period. The intervention participants will receive a CBS about oral health and text message reminders about toothbrushing. Due to the nature of participant involvement no serious adverse events or adverse events are anticipated that will be unexpected and related.
However the following procedures will be in place to seek to capture any complications associated with the trial:
· Young people and parents/carers will be informed in the participant information sheet that they are able to report any concerns or anything out of the ordinary that has happened to them as a result of taking part in BRIGHT to the research team during the course of the study. Contact details are provided.
· The dental examination case report form will provide space for the dental examiner to record any suspected serious pathologies, safeguarding issues, or unexpected and related adverse events or serious adverse events identified at the time of the dental assessment.
The BRIGHT trial team will monitor incoming data in response to these questions.
It is expected that some participants may experience non serious adverse events such as minor discomfort in their jaw as a result of keeping their mouth open during the dental assessment, similar to that experienced during a check-up at the dentist. It is also possible that some minor bleeding from the gums might occur as a result of checking for the presence of dental plaque during the clinical examination.
It is also expected that there may be unrelated incidents of hospitalisations, illnesses, disabling/incapacitating/life-threatening conditions, other common illnesses and rarely deaths in the study population, we will not seek to record all such events. We only seek to record those that could be related and unexpected.
Reporting adverse events
Details of any SAEs or AEs reported by the participants will be considered by the principal investigators and research team. Only details of any SAEs that are required to be reported to the Research Ethics Committee i.e. events which are related to taking part in the study and are unexpected, will be recorded using a trial adverse event form. The AE reporting period for this trial begins as soon as the participant consents to be in the study and ends at the final data collection point.
Suspected serious pathology
In the very rare circumstance that a serious dental/oral issue (e.g. oral cancer, gross swelling, or sepsis) is identified during the clinical assessment, dental assessors will contact the Chief Investigator or Co-Principal Investigator, who will (in line with good practice) discuss with a second colleague to decide on the most appropriate person for the child to be referred to. If it is agreed that the young person should be referred to someone else, then the school will be contacted and, we will work with the school and the school nurse to ensure that the young person reaches the appropriate help, whether that is a health or social care professional.
Publication and dissemination policy
The study will inform the uptake of the cost-effectiveness of a low cost SMS delivered alongside a classroom-based intervention for secondary schools by local authorities or departments of education, to reduce dental caries in young adults. The results will be published in a NIHR HTA monograph and high impact, peer reviewed dental journals and in education academic journals and newsletters. The results will be presented at international and national dental and education conferences. The findings will also be disseminated to the wider public health and education audiences. A publication policy has been developed.
The study progress and findings will be communicated to schools, participants and the public via the trial website, social media and easy to read reports.