Family Access to Dentist Study
Condition: Dental Caries
MeSH terms: Dental Caries
Study type: Interventional

Summary: 
      The study is a multi-site, double blind, parallel arm, community-based randomized controlled
      trial (phase III RCT) to evaluate the effectiveness of new referral approaches to increase
      receipt of dental care among inner-city urban and rural elementary school children who were
      screened at school and have restorative treatment needs. The study has 5 arms: The
      experimental intervention is the use of a theoretically driven CSM referral letter alone, the
      letter plus a Dental Information Guide, a reduced CSM referral letter alone, or a reduced CSM
      referral letter plus a reduced Dental Information Guide. The control strategy is the use of a
      standard referral letter. All participating K-4 grade children will receive a screening at
      the beginning of the school year and at the study end point 7 months later to determine if
      the child received dental care. Due to lower than expected enrollment in both the Ohio and
      Washington sites, a second year of recruitment was added to include Bedford School District
      and East Cleveland School District (only KG and other grades if they did not enroll in the
      first year). The same study procedures, schedule and design was utilized for the second year
      of recruitment.

      The primary aim is to evaluate the effectiveness of experimental (new) versus standard
      referral approach given to parents/caregivers in increasing receipt of dental care among
      their children in grades K-4. The secondary aim is to assess changes in parent/caregiver
      illness representation/perception and behavioral intention between enrollment (beginning of
      school year) and follow-up (end of school year) to understand the underlying mechanisms of
      the new vs. standard referral approach that result in receipt of dental care.

      The hypothesis is that CSM-based interventions will increase receipt of dental care compared
      to the standard referral letter.
    

Detailed description: 
      Purpose:

      The purpose of this study is to evaluate the effectiveness of new referral approaches to
      increase receipt of dental care among inner-city urban and rural elementary school children
      who were screened at school and have restorative treatment needs. The primary outcome is the
      assessment of dental care receipt through dental exams. The secondary outcomes are change in
      caregiver illness perception, measured through the IPQ-RD, and behavioral intention measured
      through items in the caregiver questionnaire.

      Study Design:

      The study will utilize a multi-site, double-blind, parallel arm, community-based randomized
      trial design. The experimental intervention will be based upon the Common Sense Model of
      Self-Regulation (CSM) to address parent/caregiver illness perception and navigation of
      resources to increase receipt of dental care during a 7-month follow-up period for children
      with restorative dental needs. In this five arm study the new CSM theory-driven referral
      letter alone, the new CSM referral letter and Dental Information Guide (DIG), the new CSM
      theory-driven reduced referral letter alone, and the new CSM theory-driven reduced referral
      letter and reduced Dental Information Guide (DIG) will each be compared to a standard
      referral letter to increase receipt of dental care among inner-city urban African American,
      and rural Hispanic and White elementary school children.

      Participants:

      Subjects will be parents/caregivers and their children in grades K-4 in one of four school
      districts; East Cleveland City School District (OH), Cowlitz County School Districts (WA),
      Lewis County School Districts (WA), and Bedford (OH). The study will be offered to all
      caregivers and their children including those children with special health care needs. At the
      Ohio site, only English-speaking caregivers and their children will be enrolled while both
      English- and Spanish-speaking caregivers and their children will be included at the
      Washington site. At the beginning of the school year dental screening, primary caregivers
      will be randomized if their child has a tooth with an International Caries Detection and
      Assessment System (ICDAS) active lesion score of 2 or greater. Caregivers with multiple
      children in K-4 will receive the same intervention assignment. The second year of recruitment
      included Bedford School District in Ohio and East Cleveland School District KG and other
      grade families if they did not enroll in the first year.

      Procedures:

      Caregivers will be recruited at the beginning of the school year and complete baseline forms
      (consent form, Illness Perception Questionnaire-Revised for Dental (IPQ-RD) questionnaire,
      and caregiver questionnaire) prior to dental screening and randomization. Children in K-4
      whose parents have consented will receive a screening exam in early October 2015 (October
      2016 for the second year of recruitment). After screening exams, eligible caregivers of
      children with restorative referrals will be randomized into one of five study arms. Different
      referral letter with/without Dental Information Guide according to study arms will be sent
      home with the child on the day of screening and mailed to the caregiver address within 24
      hours.

      Caregivers will be followed at 2 time points: 2 weeks after the receipt of the intervention
      letter and 2 weeks prior to the final (exit) study visit examinations in May 2016 (May 2017
      for the second year of recruitment)-approximately 7 months after the initial dental exam. At
      both time points caregivers will complete the IPQ-RD and the caregiver questionnaire. A small
      sub-sample of 60 caregivers will be randomly sampled from three arms (standard letter,
      intervention letter, and intervention letter+DIG) to complete the IPQ-RD 1 month after
      enrollment for fidelity purposes. All questionnaires will be mailed to the home address and
      asked to be returned to the class-room teacher or the outreach staff. Further, outreach staff
      will ensure that the caregivers received and returned the materials through follow-up calls.
      Children will have a follow-up dental exam in May 2016 (May 2017 for the second year of
      recruitment).

      Analysis Plan:

      Primary Statistical Analysis: Descriptive statistics will include frequencies (categorical
      variables) and means (continuous variables) of baseline covariates among the five
      intervention groups. Chi-square tests (for categorical variables) and t-tests (for continuous
      variables) will be performed to test for group differences (by site and overall). In our
      primary analysis, we will fit multivariate generalized linear (specifically, logistic
      regression) models with dental care receipt as the (binary) outcome and the child as the unit
      of analysis (as receipt of dental care will be determined for each child). A generalized
      estimating equations (GEE) approach (with an exchangeable working correlation structure) will
      be used to allow for correlations among multiple children for a given caregiver. Secondarily,
      we will fit a model with a site by intervention group interaction, and the latter will be
      tested to formally assess possible intervention effect heterogeneity over sites.

      We will also consider working correlation structures (e.g., alternating logistic regressions)
      that allow for second-level clusters, namely schools (within which the first-level cluster,
      caregiver, is nested). We will determine final models based on the quasi-likelihood
      information criterion (QIC). Intervention (and other covariate) effects will be tested using
      generalized score statistics.

      Analysis of Secondary Outcomes (Questionnaire data): Summary statistics (including means and
      standard errors) for questionnaire responses for both the IPQ-RD and behavioral intention
      items within the caregiver questionnaire will be calculated by site and intervention group.
      This will be done for the overall questionnaire (IPQ-RD and behavioral intention), for each
      of the five IPQ-RD cognitive constructs, and the two behavioral intention questions. Analyses
      will be done by site and overall (controlling for site). A summary measure approach, based on
      the mean questionnaire response, will be used to compare questionnaire outcomes across
      intervention groups, for the overall questionnaire and by construct. Specifically, for each
      construct (or overall) a linear regression model will be used with the mean response as the
      dependent variable, and intervention group indicators and selected baseline (control)
      covariates as independent variables. Inferences (that is, p-values and confidence intervals)
      will be performed assuming summary measures are normally distributed. This assumption will be
      tested using the Shapiro-Wilk statistic and if violated a suitable transformation of the
      summary measure used or a nonparametric approach (e.g., using ranks of the summary measures)
      conducted.

      Missing Data:

      In the event of missing questionnaire responses, we will first assess whether the data are
      missing completely at random (MCAR), that is, whether missingness for a given item is
      dependent only on participant baseline characteristics and not further on any other item
      responses. This will be done using a generalized estimating equations (GEE) approach, that
      is, by fitting a multivariate generalized linear (e.g., logistic regression) model to missing
      data indicators for each item, including as explanatory variables selected baseline
      covariates and other item responses, and testing for an effect of the latter.

      If the MCAR assumption is deemed reasonable (no significant effect found), we will conduct
      the above regression analyses with mean outcomes based on available data. A weighted analysis
      (that is, regression with the use of the weighted least squares criterion) will be conducted
      to adjust for differential missingness (thus, non-homogeneous summary measure variances)
      among participants. If the MCAR assumption is found to be violated we will use a multiple
      imputation approach (in conjunction with the summary measure approach) using a suitable
      imputation model (i.e., using other item responses). For each construct (or overall) we will
      perform an F-test for a difference in the mean summary measure among the three intervention
      groups, and obtain nominal 95% confidence intervals for pairwise mean differences. If
      necessary, we will include a random effect for school.

      Data Management:

      Data for this study are captured using examinations, forms, questionnaires, and audio
      recordings. Study data will be collected and stored using the REDCap platform. REDCap is a
      secure, web-based application designed to support remote data capture for research studies,
      providing: 1) an intuitive interface for validated data entry, 2) audit trails for tracking
      data manipulation and export procedures, 3) automated export procedures for seamless data
      downloads to common statistical packages, and 4) procedures for importing data from external
      sources.

      Study forms will be completed by study personnel on paper, and subsequently entered into
      REDCap by study staff. Because randomization is contingent upon the computer, no paper
      randomization forms will be completed. Paper forms will be securely stored in a locked file
      cabinet at both sites when they are not in use. Completed paper forms will be transferred
      between sites via courier or other secure document service. Similarly, questionnaires used in
      the study (IPQ-RD, Caregiver Questionnaire) will be completed by subjects on paper sheets and
      returned to Outreach Workers in each school. Study staff will enter the information into the
      database. All data forms, questionnaires will be entered into database stored in a secure
      password protected computer. Recorded audios will be stored in secured/locked cabinets in one
      of the Project Coordinators' offices.

      Dental examination and study questionnaire data will be reviewed for accuracy and
      completeness after each study visit. The Outreach Workers will review the questionnaires
      after the participants have completed them, and the Project Coordinators and the Data and
      Statistics Team will do a final review after the documents have been transmitted. An annual
      report (or as requested by the DSMB or NIDCR Program Official) will also be generated for
      sharing progress of the study.

      The Data & Statistics Team will generate regular reports showing enrollment and potential
      data anomalies, which will be sent to PIs, Project Coordinators, and other relevant study
      staff. The Data Manager will work with the PIs at each site to resolve any data anomalies
      that arise during recruitment. The Data & Statistics Team will also respond to data queries
      generated by the PIs, Project Coordinators, or other study staff.

      Statistical analyses and summary reports will be generated by the study Biostatistician
      during the course of the study. At the end of the study, the study Biostatistician will
      conduct analyses of the data and assist in preparation of study publications and
      presentations. The Data Manager will provide technical and data support for the
      Biostatistician throughout the study.
    

Intervention name(s): Standard letter; Intervention letter; Reduced intervention letter; DIG; Reduced DIG
Intervention type(s): Behavioral; Behavioral; Behavioral; Behavioral; Behavioral
Intervention description(s): Standard referral letter according to Ohio Department of Health Bureau guidelines. This letter is consistent with others used across the country.; Referral letter based on the Common Sense Model of Self-Regulation (CSM). The letter includes the cognitive dimensions of the CSM (identity, cause, timeline, consequences and control).; Reduced (removing text corresponding to "timeline") CSM theory-based referral letter. The letter includes the remaining cognitive dimensions of the CSM (identity, cause, consequences and control).; Dental information guide (DIG) to reinforce/change illness perception, knowledge about dental caries, and resources to seek care. DIG is a brochure with illustrations which provides myths and facts about dental caries, hints for getting dental care, making appointments and Medicaid access, transportation and dentist availability resources.; Text and illustrations related to the "timeline" construct of the CSM have been removed in the reduced dental information guide.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Health Services Research
Keywords: Dental Care; Caregiver Illness Perception; Common Sense Model of Self-Regulation; Dental Access; Referral letter; Dental Caries