Effect of the SIMS Programme on Preschool Children's Oral Hygiene Level
Condition: Dental Plaque
MeSH terms: Dental Plaque
Study type: Interventional

Summary: 
      This is a cluster randomised control trial targeting 5-6-year-old children and their parents
      in Kampar district, Perak, Malaysia for a period of 6 months. In total, 28 preschools are
      randomly assigned into intervention and control group (14 preschools per group). Sample size
      for each group is 317 children. The intervention group receives the SIMS programme (SIMSP)
      which is an improved version of the usual care, while the control group receives the usual
      care. Usual care in defined as the existing preschool oral health programme (POHP) offered by
      the Ministry of Health. The SIMSP is formulated based on the recommendations from the
      National Oral Health Survey of Preschool Children's (2015) report. It comprises active
      participation of dental therapists (DT), parents and class teachers in children's oral
      health. The concept of the SIMSP is that improvement in oral health behaviours and oral
      hygiene of preschool children would result in improvement of gingival health and caries level
      in their permanent teeth in the long term. On the other hand, the control group involves DT
      visiting preschools twice a year without parental nor teachers active involvement. The
      scientific hypothesis of the study is that the SIMSP is more effective to improve oral
      hygiene level of preschool children than the POHP over 6 months. The primary objective of the
      study is to assess the effect of the SIMSP versus the POHP in improving oral hygiene level
      among 5-6-year-old children over 6 months. The secondary objectives are to assess the changes
      in oral health behaviours among the children and oral health literacy among parents over 6
      months.
    

Detailed description: 
      Study Design:

      This is a cluster randomised controlled trial. The overall duration of the study is 9 months
      and the duration of the intervention is 6 months. The reporting of this study is done in
      accordance with the SPIRIT 2013 guidance for protocols of clinical trials and the CONSORT
      checklist.

      Study setting:

      The study involves government-funded preschools that receive the POHP in Kampar district,
      Perak, Malaysia. Based on this criteria, 53 preschools in Kampar district are eligible to be
      included in the study.

      Randomisation:

      The 53 preschools are paired according to geographical location and preschool characteristics
      into 24 pairs (5 preschools are not paired). Of the 24 pairs, 14 pairs are randomly selected
      using computer generated table. Subsequently, 2 preschools in each pair is randomly assigned
      to intervention and control group each using computer generated table.

      Sample recruitment:

      The study sample consists of 5-6-year-old preschool children from the 24 preschools and their
      parents. A written informed consent is obtained from parents and verbal agreement is obtained
      from children prior to the start of the study.

      Sample size calculation:

      Sample size calculation is based on the potential effect of the SIMSP to exert a small effect
      size dz = 0.30, α = 0.05, power = 0.8 on children's plaque score (primary outcome measure)
      and parental oral health literacy (OHL - secondary outcome measure) than the POHP over 6
      months. Using G*Power version 3.1.9.2 software, the total number of sample is n = 352 (176
      per group). Sample size calculation is also done based on the effect of the SIMSP to produce
      a 10% improvement (α = 0.05, power = 0.8) in child's oral health behaviours (OHB) than the
      POHP after 6 months. Using Power and Sample Size Calculation version 3.1.2 software, the
      total number of sample was n = 348 (174 per group). The highest total sample size (n = 352)
      is increased by 20% to account for non-respondents and multiplied by a design effect of 1.5
      to produce final sample size, n = [352 + (352*0.2)] x 1.5 = 634 (317 per group).

      Intervention:

      The SIMSP, which refers to 'Program Senyuman Indah Milik Semua' in Malay, or 'The Beautiful
      Smile for All Programme' in English, consists of 3 components conducted by a dedicated team
      of DT (4 persons), parents, and preschool teachers. The target groups are preschool children
      and their parents/guardians. The content of the SIMSP is as follows:

      Preschool children:

        1. Oral examination by DT, oral health education (OHE) and fluoride varnish application
           twice/year (usual care/POHP);

        2. In-school daily toothbrushing with fluoride toothpaste (1000ppm) supervised by the class
           teacher for 6 months;

        3. Oral health lessons in class (including colouring worksheets) by the class teacher based
           on the Oral Health Education (OHE) booklet over a period of 6 months;

        4. Home tooth brushing supervision by parents/guardians bedtime.

      Parents/guardians:

        1. Attend a meeting with DT at school to discuss on child's Caries Risk Assessment (CRA);

        2. Receive OHE and diet counselling from DT based on child's CRA levels;

        3. Receive free toothbrush and fluoride toothpaste (1000ppm) for child home tooth brushing;

        4. Receive 10 oral health infographic messages from DT, delivered via electronic messaging
           application (WhatsApp) every 2 weeks for a duration of 5 months (printed leaflets
           delivered through class teacher for parents without a smartphone).

      Control:

      Oral examination by DT, oral health education (OHE), and fluoride varnish application
      twice/year (usual care/POHP).

      Conduct of the study:

      (A) Prior to intervention - development of the Oral Health Education booklet for teacher,
      training of teachers on its use, and development of oral health infographics for parents.

      (B) Delivery of the intervention - the intervention is delivered in 3 phases;

      Phase 1:

      It involves an oral examination (including plaque assessment) of children in both groups by
      DT. On the same visit, a self-administered questionnaire is sent to parents through class
      teacher and collected after 1 week. Data in Phase 1 are baseline data for the study.

      Phase 2:

      This phase takes place 2 weeks after Phase 1. In the SIMSP, DT deliver OHE to children and
      apply fluoride varnish (20,000 ppmF) on their teeth. DT meet up with parents to discuss on
      child's CRA and provide OHE and diet counselling to parents according to their child's caries
      risk levels (low/medium/high). A set of free toothbrush and fluoride toothpaste (1000ppm
      fluoride) is distributed to parents for child's home use along with instructions on
      toothbrushing. Parents also receive 10 oral health infographics sent by DT via WhatsApp every
      2 weeks for the next 5 months. Teachers are provided with the OHE booklet which contains 11
      topics (and worksheets) to be used as a teaching aid to teach oral health lessons in class.
      Teachers are required to deliver 1 topic lesson every 2 weeks until all the 11 topics are
      delivered over 6 months. Teachers are also given enough supplies of toothbrush and fluoride
      toothpaste for children's tooth brushing after morning break at school over 6 months.
      Teachers are given a tooth model and instructions on toothbrushing by DT. In the control
      group, DT deliver OHE to children and apply fluoride varnish (20,000 ppmF) on their teeth.

      Phase 3:

      This phase takes place 24 weeks after Phase 2. In this phase, DT carry out restorative
      treatment on children using glass inomer cements followed by second application of fluoride
      varnish. This is carried out in both groups. The 6-month follow up for oral examination on
      children and parental questionnaire are carried out within 2 weeks after completion of Phase
      3.

      Monitoring the intervention:

      The intervention is monitored by means of an activity book to be completed by DT, parents,
      and teachers, respectively throughout the 6 months. DT will tick off all activities that have
      been carried out at preschool in the 3 phases over the duration of 6 months. Accordingly,
      teachers will tick off the scheduled class lessons and daily toothbrushing activities.
      Parents will tick off the daily toothbrushing supervision of their children before bedtime.
      The activity books are reviewed periodically to assess for compliance. In terms of oral
      examination and parental questionnaire, those who are lost to follow up will not be replaced.
      Analysis will be by intention to treat.

      Study tools:

        1. A self-administered questionnaire consisting of 3 sections; (a) Demographics of the
           child and parents/guardians, (b) Child's oral health behaviours, and (C) The Malay
           version of Dental Health Literacy Assessment Instrument (Malay-DHLAI).

        2. The Oral Cleanliness Index to assess plaque level.

        3. The International Caries Detection and Assessment System (ICDAS) to assess caries.

      Blinding:

      This study uses a single-blinding strategy where the examiners who examine the children at
      baseline and 6-month follow up are blinded to the intervention group.

      Calibration of examiners:

      3 dental officers undergo calibration and standardisation on the use of ICDAS and Oral
      Cleanliness Index with a paediatric dentist. Calibration and standardisation are carried out
      at the Faculty of Dentistry, University of Malaya and again in field condition at one of the
      preschools not involved in the study. Inter- and intra-examiner reliability are assessed for
      both ICDAS and plaque score charting. Kappa score is used to assess agreement between and
      within examiners. For ICDAS, the inter-examiner Kappa scores ranged from 0.72-0.80 and the
      intra-examiner scores ranged from 0.70-0.84. For plaque scores, the inter-examiner Kappa
      scores ranged from 0.72-.80 and the intra-examiner scores ranged from 0.77-0.94.

      Data management:

      Data are checked after completion of oral examinations and after receiving the
      questionnaires. For any missing data, the child will be re-examined or the parents will be
      contacted again. Raw data are entered into Statistical Package for Social Science (SPSS)
      version 24.

      Qualitative data collection:

      Focus group discussions (FGD) with DT and preschool teachers are conducted separately to
      explore their perspectives on the process implementation of the SIMSP according to their
      roles and responsibilities. A topic guide with open-ended questions are developed and use in
      the FGD to get feedback on the appropriateness, feasibility (facilitators and barriers),
      effectiveness, and recommendations for improvement on the SIMSP.

      Statistical Analysis:

      Data analysis is conducted using SPSS version 24 software, and Qualitative Data Analysis
      Software (NVivo) version 11 software.

      Descriptive Analysis:

      The frequency distribution, a measure of central tendency and dispersion are carried out.
      Continuous data are presented in mean and standard deviation (or median and interquartile
      range) based on the normality of the data. Categorical data are presented in frequency and
      percentages. The demographics of the sample are analysed using descriptive statistics.

      Effectiveness Analysis:

      Intention to Treat (ITT) analysis will be applied to measure the effect of the SIMSP on the
      primary and secondary outcome measures over and above that by the usual care. Pearson Chi
      Square test is used to assess differences in the proportion of children with plaque between
      groups at baseline and after 6 months. Independent sample T-test is used to assess the
      difference in mean decrement plaque scores after 6 months between groups, and Paired sample
      T-test was used to assess within-group changes. Effect size of the SIMSP is calculated.
      Similar statistical tests are used to assess the differences in parental OHL between the
      groups after 6 months. For children's OHB, Pearson Chi Square test is used to assess
      differences in children's OHB between groups at baseline and after 6 months, while McNemar
      test is used for within-group changes in proportions.
    

Intervention name(s): The SIMS programme
Intervention type(s): Behavioral
Intervention description(s): The intervention targets 5-6-year-old preschool children and their parents. Apart from the usual care, 5-6-year-old children receive oral health lessons and supervised daily tooth brushing (1000ppm F) at school over a period of 6 months, as well as home tooth brushing supervision by parents for 6 months. Parents/guardians attend a meeting with a DT team at school to discuss on child's oral health status, receive OHE and free toothbrush and fluoride toothpaste (1000ppm F) for child home tooth brushing, and receive 10 oral health infographic messages from DT over a period of 5 months (with printed versions available).
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Cluster Randomised Controlled Trial
Masking: Single (Outcomes Assessor)
Primary purpose: Prevention
Keywords: Preschool; Children; Dental plaque; Oral health behaviour; Health literacy