Older Adult Effectiveness of 2 Treatments

  • End date
    Mar 31, 2023
  • participants needed
  • sponsor
    Case Western Reserve University
Updated on 24 January 2021


The study is a cluster randomized clinical trial (RCT) to be conducted in 22 publicly subsidized housing facilities/sites (HUD Section 202) and other low-income housing voucher programs in NE Ohio. The facilities will be randomized to 2 arms: Arm 1 (11 sites) - Participants will receive biannual silver diamine fluoride (SDF) versus Arm 2 (11 sites): Participants will receive atraumatic restorative treatment (ART) with glass ionomer cement (GIC) + biannual fluoride varnish (FV) application. A total of 550 participants (Arm 1: 275, Arm 2: 275) will be followed for one year (baseline, 26 weeks, 52 weeks).

The protocol for each arm will address both coronal and root surface tooth decay lesions: Arm

  1. The treatment will be bi-annual topical 38% SDF(Advantage Arrest, Elevate Oral Care LLC., West Palm Beach, FL) following manufacturer's instructions and published guidelines; Arm 2: The treatment will be ART will be a modification where the cavity will be restored with high viscosity glass-ionomer cement (GIC) (GC Fuji Automix LC Resin Reinforced Glass Ionomer Restorative, Japan)). Patients will also receive biannual topical fluoride varnish treatments (FluoriMax, Elevate) according to manufacturer's instructions.


Study Design:

A cluster randomized clinical trial (RCT) is planned in 22 publicly subsidized housing facilities (HUD Section 202) and other low-income housing voucher programs in NE Ohio and will be randomized to 2 arms: Arm 1 (11 sites) - Participants will receive biannual SDF; Arm 2 (11 sites): Participants will receive ART + FV biannual application. All participants will be followed for one year and will receive a dental screening and prophylactic cleaning at all visits.

Study Population and Setting:

The long-term goal is to reduce disparities and improve oral health equity for low-income older adults. The immediate goal is to test interventions to address disparities. Therefore, the population/setting will be low socioeconomic status (SES) adults 62 years of age in 6 NE Ohio counties (Cuyahoga, Lorain, Summit, Ashtabula, Geauga, and Lake) residing in HUD Section 202 and other publicly subsidized housing facilities. Administrators have provided letters of support confirming the availability of sites and intent to participate. The population is diverse: African American/Black, Caucasian/White including Hispanic/Latino, and Asian. There are 64 HUD housing sites with 3,661 tenant units in the 6 counties. An additional 87 low-income facilities housing elderly are accounted for by regional housing authorities, adding 11,667 units. Therefore, a total of 151 facilities and 15,328 older adults are available.

The sample size goal of 22 sites and 550 participants will be easily achieved. Medicaid participation among the tenants is 76% among facilities. From a prior study in these facilities it is expected that the mean age is 74 years, 76% female, 51% Caucasian, 45% African-American, 2% Hispanic, and 2% other racial/ethnic groups; 60% of HUD older adults had none/rare dental visits in over 3 years.

Recruitment of Participants:

Successful strategies from prior studies will be used in recruiting and input will be solicited from the stakeholders. Strategies that will be used are as follows: Service coordinators at all 22 facilities will serve as site liaisons. The study PI/project manager will provide the service coordinators with an introductory letter/flyer containing study information to be given to tenants and to be posted in public areas of the facility. Service coordinators will first arrange an informational meeting (study dentist will give a talk on the interventions as suggested by our stakeholders), and will arrange a second recruitment meeting for study staff to present information regarding the study at scheduled group events (e.g. tenant meetings, health fairs). For planning purposes, service coordinators will have a sign-up sheet for those interested in the sessions. Study staff will schedule those who are interested and meet the inclusion criteria for one-on-one sessions at the housing facility to obtain informed consent and collect baseline survey data. Baseline dental exam and treatment appointments will then be scheduled at each facility according to a designated exam day(s) for each facility, which will occur approximately 1-2 weeks following consent and baseline data collection. Six and twelve month dental exams/treatment and one-on-one interviews for follow-up survey completion for each time point will also occur at the housing facility where participants reside.

Randomization Procedures:

Randomization is at the level of the cluster (housing facility) for logistical efficiency. This will greatly reduce the potential for error that could otherwise occur with people at the same site assigned to different treatments. Furthermore, keeping the same treatment at each site reduces chances of 'contamination' (i.e. participant discussing their treatment with others). Additionally, stratified cluster randomization will be used, i.e. a block (constrained) randomization approach in which balance over treatments is assured for 2 key cluster-level (stratification) variables, namely facility size (>100 versus 100 residents), and geographic location (Cuyahoga County vs other). The project statistician will generate the randomization scheme for the 22 housing facilities.

Analytic plan:

Each primary outcome will be compared between the SDF and ART+FV groups. For tooth pain, a 95% confidence interval (CI) based on a t-test for the difference in mean responses (SDF minus ART+FV) will be computed. If this confidence interval lies within the interval (-, 8) we may conclude 'non-inferiority' of SDF relative to ART+FV treatment. The confidence interval may secondarily be examined to assess possible superiority of one intervention over the other. For arrest rate, a 95% CI for the difference in rates (based on a z statistic) will be computed. If this confidence interval lies within the interval (-0.09, 1) we may conclude 'non-inferiority' of the SDF relative to ART+FV treatment. As above, possible superiority of one intervention over the other may also be assessed. For other outcomes, computing 95% CI for differences in means (or proportions for binary outcomes) will also be used. These secondary outcomes will be assessed in an exploratory manner for possibly superiority or inferiority based on appropriate margins.

To corroborate initial results, a generalized estimating equations (GEE) approach will be used. For each outcome, a GEE (marginal) model will be fit that includes a treatment indicator and prognostic variables (including sociodemographic variables, medical conditions, and oral health behaviors). Appropriate link functions (e.g., logit link for binary outcomes and identity link for continuous outcomes) will be specified and an exchangeable working correlation matrix used to allow for correlations within site. The arrest outcome will be analyzed as a binary outcome (as described in the sample size section), and secondarily as the number of arrested lesions assuming an appropriate distribution (e.g., negative binomial) and link function (e.g., log link). Robust t tests with correction for a small number of clusters will be used to test for treatment effects and corresponding 95% confidence intervals computed.

Secondarily, the above GEE approach will be extended to analyze the repeated (baseline, 26 and 52 week) measures for each outcome. The models for each outcome will include the same prognostic variables as before, as well as time and a time by treatment interaction. Correlations among the repeated measures will be allowed, e.g., using a first-order autocorrelation structure. If a substantial within-facility correlation is found it would be necessary to incorporate facility as a second cluster levels (within which person - the first cluster level - is nested). Additionally, estimation and testing (via a robust t-test) the interaction term to compare trends over time for the two interventions will also be employed. If the use of two cluster levels is not found to be feasible in the GEE approach, a generalized mixed effects model approach will be considered.

Causal Inference standards: The use of randomization and adjustment in regression models should be sufficient to provide causally interpretable intervention effect estimates; special causal inference techniques such as propensity score or instrumental variable methods often indicated for observational studies, will therefore not be necessary for the data analysis. Biases will be avoided in causal inferences about the intended interventions by using an intent-to-treat approach, in which individuals are analyzed according to randomized groups without regard to (extent of) treatment actually received.

Sensitivity Analyses: Sensitivity of conclusions to model assumptions will be checked as well as methodological decisions such as outcome definition. In particular, for the arrest outcome, the primary analysis is based on a binary indicator of 'complete' arrest of all lesions for an individual. Results will be corroborated from this approach with an alternative approach analyzing number of lesions arrested. For the GEE analyses, planned for all outcomes, sensitivity will be assessed in part by using alternative working covariance structures and alternative sets of predictors. For some outcomes, alternative distributions will be considered; for example, for number of arrested lesions, possible distributions include Poisson, negative binomial, zero-inflated Poisson (ZIP), and zero-inflated negative binomial (ZINB). Sensitivity to assumptions regarding missing data will also be investigated as described further below.

Missing Data. (a) Methods to prevent and monitor missing data: All questionnaires (using tablets) and dental assessment forms (using paper), will be managed in an electronic database (REDCap) by study staff. Weekly quality control checks will be run for outliers, entry errors, missing data, and potential data anomalies. Statistical analyses, summary and missing data reports will be generated by the study biostatistician monthly during the study. (b) Statistical Methods to Handle Missing Data and Account for Statistical Uncertainty Due to Missingness: The primary analyses, which use GEE based on all available observations, assume outcomes are missing completely at random (MCAR). As an initial assessment of missing data patterns, intervention groups (including by relevant subgroups and time point) will be compared with regard to missing outcome rates. A test for a relationship between missingness and outcomes at early time points will evaluate the plausibility of the MCAR assumption. Multiple imputation methods (an established method) will be used to help assure valid inferences. (d) Plans to Record and Report Dropout and Missing Data: The trial data will be managed using REDCap software, currently running at Case Western Reserve University (CWRU). REDCap is a secure web-based application providing an intuitive interface for validated data entry, audit trails for tracking data manipulation and export procedures, and automated export procedures for seamless data downloads to common statistical packages. Missing data reports will be generated weekly from REDCap for timely resolution and reporting purposes. (e) Plans to Examine Sensitivity of Inferences to Missing Data Methods As noted above, multiple imputation will be used to obtain valid inferences in the presence of data that are not missing completely at random. Predictive mean matching with an appropriate prediction model will be used depending on the outcome (e.g. logistic regression for binary outcomes, linear regression for continuous and count outcomes). Alternative imputation models will be used as part of sensitivity analyses.

Condition Dental caries, cavities, cavity, caries, tooth decay
Treatment A "simple medical strategy" consisting of silver diamine fluoride (SDF), B "typical dental strategy" consisting of atraumatic restorative treatment (ART) with glass ionomer cement + Fluoride varnish (FV)
Clinical Study IdentifierNCT03916926
SponsorCase Western Reserve University
Last Modified on24 January 2021


Yes No Not Sure

Inclusion Criteria

Provide signed and dated informed consent form
Willing to comply with all study procedures and be available for the duration of the study (1 year)
Male or female, aged 62 years or older
Live in a participating older adult housing facility to continue in the clinical trial phase of the study, an individual must
Have at least one untreated active root or coronal carious lesion with ICDAS-II (2015) lesion severity code of 3 or greater

Exclusion Criteria

Sensitivity to silver or other heavy-metal ions
Those with ulcerative gingivitis or stomatitis
Serious life-threatening medical disease
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact



Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note