Calibration and reliability testing of a novel asynchronous photographic plaque scoring system in young children

OBJECTIVES

The Simplified Oral Hygiene Index for Maxillary Incisors (OHI-MIS) is a novel plaque scoring system adapted for young children. This study describes calibration training and testing used to establish the inter- and intra-rater reliability for OHI-MIS measured from clinical photographs.

METHODS

Two raters from the Coordinated Oral Health Promotion Chicago (CO-OP) and one from the Behavioral EConomics for Oral health iNnovation (BEECON) randomized controlled trials (RCTs) underwent calibration with gold standard raters, followed by annual re-calibration. Raters from CO-OP also completed inter-rater reliability testing; all three raters completed intra-rater reliability testing rounds. Photographs were obtained from children aged 9-39 months.

RESULTS

All three raters achieved greater than 0.77 Lin's Concordance Correlation (LCC) versus gold standard consensus during calibration. All three raters had LCC ≥0.83 at recalibration 1 year later. CO-OP trial raters scored 604 photos (151 sets of 4 photographs); mostly both raters were somewhat/very confident in their scoring (≥89%), describing the most photos as "clear" (90% and 81%). The CO-OP inter-rater LCC for total OHI-MIS score was 0.86, changing little when low quality or confidence photos were removed. All three raters demonstrated high intra-rater reliability (≥0.83).

CONCLUSIONS

The OHI-MIS plaque scoring system on photos had good reliability within and between trials following protocol training and calibration. OHI-MIS provides a novel asynchronous plaque scoring system for use in young children. Non-clinicians in field or clinical settings can obtain photographs, offering new opportunities for research and clinical care.

Monetary incentives for improving smartphone-measured oral hygiene behaviors in young children: A randomized pilot trial

AIMS

To assess feasibility, acceptability, and early efficacy of monetary incentive-based interventions on fostering oral hygiene in young children measured with a Bluetooth-enabled toothbrush and smartphone application.

DESIGN

A stratified, parallel-group, three-arm individually randomized controlled pilot trial.

SETTING

Two Los Angeles area Early Head Start (EHS) sites.

PARTICIPANTS

36 parent-child dyads enrolled in an EHS home visit program for 0-3 year olds.

INTERVENTIONS

Eligible dyads, within strata and permuted blocks, were randomized in equal allocation to one of three groups: waitlist (delayed monetary incentive) control group, fixed monetary incentive package, or lottery monetary incentive package. The intervention lasted 8 weeks.

OUTCOMES

Primary outcomes were a) toothbrushing performance: mean number of Bluetooth-recorded half-day episodes per week when the child's teeth were brushed, and b) dental visit by the 2-month follow-up among children with no prior dental visit. The a priori milestone of 20% more frequent toothbrushing identified the intervention for a subsequent trial. Feasibility and acceptability measures were also assessed, including frequency of parents syncing the Bluetooth-enabled toothbrush to the smartphone application and plaque measurement from digital photographs.

FINDINGS

Digital monitoring of toothbrushing was feasible. Mean number of weekly toothbrushing episodes over 8 weeks was 3.9 in the control group, 4.1 in the fixed incentive group, and 6.0 in the lottery incentive group. The lottery group had 53% more frequent toothbrushing than the control group and 47% more frequent toothbrushing than the fixed group. Exploratory analyses showed effects concentrated among children ≤24 months. Follow-up dental visit attendance was similar across groups. iPhone 7 more reliably captured evaluable images than Photomed Cannon G16.

CONCLUSIONS

Trial protocol and outcome measures were deemed feasible and acceptable. Results informed the study protocol for a fully powered trial of lottery incentives versus a delayed control using the smart toothbrush and remote digital incentive program administration.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT03862443.

Calibration of dentists for Caries Management by Risk Assessment Research in a Practice Based Research Network - CAMBRA PBRN

Background

To prove that Caries Management by Risk Assessment (CAMBRA) can be successfully implemented in dental practices outside of the university setting, dentists in the San Francisco Bay Area (CA) were approached to participate in a Practice Based Research Network (PBRN) study. The overall goal of the CAMBRA-PBRN study was to recruit 30 dentists to perform a two-year study involving approximately 900 patients. Goal of the calibration study was to standardize and calibrate dentists potentially participating in the CAMBRA-PBRN study.

Methods

To minimize inter-examiner variability in data collection, including classification of carious lesions and recording of existing restorations, participating dentists were trained and calibrated in accurate DMFS (decayed, missing, filled surfaces) charting. Dentists were also trained and calibrated to diagnose and differentiate between sound surfaces and non-cavitated caries lesions (International Caries Detection and Assessment - ICDAS scores 1 and 2) for posterior occlusal surfaces.

Thirty dentists were calibrated to a single gold standard examiner (BJ) during 6 calibration sessions, between 2011 and 2014. Kappa statistics were used to determine inter-examiner reliability on 13 or more patients, aged 12–63 (average age 38 ± 15 years), per examiner during each session, resulting in 94 patient encounters over the course of all 6 sessions. To participate in the main study, examiners needed to achieve a minimum required kappa of 0.75. During the calibration process, examiners scored between 1036 and 2220 tooth surfaces.

Results

The kappa values (unweighted kappa) of the participating dentists compared to the gold standard examiner ranged from 0.75 to 0.90, with an average kappa of 0.84 ± 0.03. 90% of the examiners achieved overall kappa values above 0.8. However, separate reliability for assessment of non-cavitated lesions, as in other studies, was lower (0.55 ± 0.15). Multiple subcategories were evaluated. All dentists reached sufficient reliability values to proceed into the study; nevertheless, one dentist discontinued with the study due to scheduling conflicts.

Conclusions

The high inter-examiner reliability results have shown that dentists who work in primarily non-research based practices can be effectively standardized and calibrated in data collection, based on specific guidelines created to anticipate potential research study scenarios.

Examination criteria and calibration procedures for prevention trials of the Early Childhood Caries Collaborating Centers

OBJECTIVES

To summarize diagnostic criteria and examiner training and calibration of the National Institute of Dental and Craniofacial Research-funded Early Childhood Caries Collaborating Centers (EC4) and report examiner calibration results from 2010 to 2014. The EC4 at Boston University, University of Colorado, and University of California San Francisco are performing randomized controlled early childhood caries (ECC) prevention trials with caries as the main outcome measure.

METHODS

The EC4 with University of Iowa consultants developed standardized tooth and tooth surface status examination criteria for use in field conditions, examiner training materials, and examiner calibration and re-calibration methodologies. Calibration and re-calibration were performed with 1- to 5-year-old children in the San Francisco Mission District in which assessments from each examiner to be calibrated were compared with those from a single gold standard examiner from 2010 to 2014. Cohen's kappa statistic was used to determine inter-examiner agreement.

RESULTS

A total of seven examiners were successfully (re)calibrated during that period, examining a total of 231 children. Overall unweighted Cohen's kappas for 10 surface conditions exceeded the criterion of 0.70. However, separate agreement for assessment of noncavitated lesions, as in other studies, was lower.

CONCLUSIONS

An experienced multidisciplinary and multi-institutional team was able to develop criteria and training materials to anticipate situations and field conditions the main trials would encounter. Examiners were successfully trained and (re)calibrated.

Mother and youth access (MAYA) maternal chlorhexidine, counselling and paediatric fluoride varnish randomized clinical trial to prevent early childhood caries

BACKGROUND

Mexican-American children have a higher caries prevalence than the U.S. average. The Mothers and Youth Access (MAYA) study was a randomized clinical trial initiated to address this problem.

AIM

Comparison of the efficacy of two prevention interventions in reducing early childhood caries (ECC).

DESIGN

All 361 randomized mother-child dyads received oral health counselling. Beginning at 4 months postpartum, intervention mothers received chlorhexidine (CHX) mouthrinse for 3 months beginning 4 months postpartum and children received fluoride varnish (FV) every 6 months from age 12-36 months. Control group children received FV if precavitated lesions developed. Salivary mutans streptococci (MS) and lactobacilli were assessed.

RESULTS

No significant difference in children's 36-month caries incidence between groups; 34% in each group developed caries [(d(2+) fs) > 0]. About half of control group developed precavitated lesions and received therapeutic FV. Maternal MS levels declined during CHX use, but increased when discontinued.

CONCLUSIONS

Maternal postpartum CHX regimen, oral health counselling and preventive child FV applications were not more efficacious than maternal counselling with child therapeutic FV for precavitated lesions for ECC prevention. FV for young children with brief maternal CHX use and oral health counselling may need to be combined with additional or longer-term therapies to significantly reduce ECC in high-risk populations.

Recruiting and retaining pregnant women from a community health center at the US-Mexico border for the Mothers and Youth Access clinical trial

BACKGROUND

Recruitment and retention in clinical trials of minorities is low, particularly in rural underserved populations. This has slowed progress in addressing racial/ethnic disparities in oral health.

PURPOSE

To describe factors associated with successful recruitment, and identify predictors of continued retention of pregnant women attending a community health center into a randomized controlled clinical trial to prevent early childhood caries.

METHODS

The Mothers and Youth Access (MAYA) Trial recruited women in the second trimester of pregnancy. At baseline, consenting women completed an oral health questionnaire and received a dental exam and oral health counseling. Four months postpartum, women returned with their babies for randomization with follow up at 9-, 12-, 18-, 24-, 30-, and 36-month postpartum visits. To assess predictors of retention, data about respondents' demographics, and oral health-related knowledge, attitudes, and behaviors were obtained by questionnaire and analyzed by logistic and discrete time-to-event regression analyses.

RESULTS

Of 556 predominantly Mexican-American women recruited at baseline, 195 (35%) were excluded after baseline for not meeting inclusion criteria; 361 (65%) continued to randomization. Factors such as race/ethnicity, annual household income, household composition, oral health-related knowledge and behaviors significantly related to retention until randomization. In multivariable models, women reporting a higher annual household income were less likely to be lost to attrition before randomization (odds ratio = 0.73, 95% confidence interval (CI) 0.60-0.89); while Mexican/Mexican-American women were less likely to be lost beyond randomization (hazard ratio = 0.53, 95% CI 0.26-1.08).

LIMITATIONS

Factors not measured at baseline may have been important in predicting attrition. The MAYA Trial is expected to finish by November 2008; therefore, complete results for total retention may differ from those reported here.

CONCLUSIONS

Recruitment and retention efforts for pregnant Hispanic women should place heavy emphasis on culture as ethnicity remained the only borderline significant predictor in postrandomization retention.

Fluoride varnish efficacy in preventing early childhood caries

To determine the efficacy of fluoride varnish (5% NaF, Duraphat, Colgate) added to caregiver counseling to prevent early childhood caries, we conducted a two-year randomized, dental-examiner-masked clinical trial. Initially, 376 caries-free children, from low-income Chinese or Hispanic San Francisco families, were enrolled (mean age +/- standard deviation, 1.8 +/- 0.6 yrs). All families received counseling, and children were randomized to the following groups: no fluoride varnish, fluoride varnish once/year, or fluoride varnish twice/year. An unexpected protocol deviation resulted in some children receiving less active fluoride varnish than assigned. Intent-to-treat analyses showed a fluoride varnish protective effect in caries incidence, p < 0.01. Analyzing the number of actual, active fluoride varnish applications received resulted in a dose-response effect, p < 0.01. Caries incidence was higher for 'counseling only' vs. 'counseling + fluoride varnish assigned once/year' (OR = 2.20, 95% CI 1.19-4.08) and 'twice/year' (OR = 3.77, 95% CI 1.88-7.58). No related adverse events were reported. Fluoride varnish added to caregiver counseling is efficacious in reducing early childhood caries incidence.

Implementing an infant oral care program

The American Academy of Pediatric Dentistry, American Dental Association, American Public Health Association, Association of State and Territorial Dental Directors, California Dental Association, and California Society of Pediatric Dentists currently recommend that children receive their first dental evaluation within the first year of life. Providing early care to children from ages 6 months to 5 years offers an opportunity to educate and inform parents about their children's oral health. Anticipatory guidance - counseling of parents by health providers about developmental changes that will occur in their children between health visits - for children's dental health is an important part of preventive care. It may be the most effective way to prevent problems that traditional infectious disease models have failed to address, such as early childhood caries. The model of anticipatory guidance is valuable for dental professionals because it emphasizes prevention of dental problems rather than restorative care. A comprehensive infant oral care program utilizes (1) oral health assessment at regularly scheduled dental visits, (2) risk assessments, (3) counseling sessions with parents during either regular dental visits or additional visits scheduled if a child is deemed at risk, (4) preventive treatment such as the application of fluoride varnish or sealants, and (5) outreach and incentives to reinforce attendance. Facilitating access to early and regular dental care is a crucial part of any effective intervention strategy, and intervention techniques should be tailored to the community being served.

The mechanical properties of the rabbit and human cornea

The extensibility of rabbit and human corneas was measured by raising the pressure within the intact globe of the eye and measuring the displacements of two very small mercury drops on the corneal surface. The human cornea showed a negligible extensibility under low stresses. The rabbit tissue, however, underwent a 9% strain under low pressures with a curvilinear relationship between stress and strain. At higher pressures the relationship was linear, and the tissue showed some creep. The low pressure stress-strain relationship of the rabbit could not be explained on the basis that the collagen fibrils were being straightened out from an initial set in a sinusoidal wave. When the stroma was isolated from Descemet's membrane, it showed a negligible low pressure extensibility in rabbit and man. On the other hand, isolated Descemet's membrane was very extensible in both species. The difference between them in the behavior of the intact cornea seems to lie in the relative initial strain in the stroma and Descemet's membrane.