Interpreting Poisson Regression Models in Dental Caries Studies

Bayesian modeling of spatially differentiated multivariate enamel defects of the children's primary maxillary central incisor teeth

BACKGROUND

The analysis of dental caries has been a major focus of recent work on modeling dental defect data. While a dental caries focus is of major importance in dental research, the examination of developmental defects which could also contribute at an early stage of dental caries formation, is also of potential interest. This paper proposes a set of methods which address the appearance of different combinations of defects across different tooth regions. In our modeling we assess the linkages between tooth region development and both the type of defect and associations with etiological predictors of the defects which could be influential at different times during the tooth crown development.

METHODS

We develop different hierarchical model formulations under the Bayesian paradigm to assess exposures during primary central incisor (PMCI) tooth development and PMCI defects. We evaluate the Bayesian hierarchical models under various simulation scenarios to compare their performance with both simulated dental defect data and real data from a motivating application.

RESULTS

The proposed model provides inference on identifying a subset of etiological predictors of an individual defect accounting for the correlation between tooth regions and on identifying a subset of etiological predictors for the joint effect of defects. Furthermore, the model provides inference on the correlation between the regions of the teeth as well as between the joint effect of the developmental enamel defects and dental caries. Simulation results show that the proposed model consistently yields steady inferences in identifying etiological biomarkers associated with the outcome of localized developmental enamel defects and dental caries under varying simulation scenarios as deemed by small mean square error (MSE) when comparing the simulation results to real application results.

CONCLUSION

We evaluate the proposed model under varying simulation scenarios to develop a model for multivariate dental defects and dental caries assuming a flexible covariance structure that can handle regional and joint effects. The proposed model shed new light on methods for capturing inclusive predictors in different multivariate joint models under the same covariance structure and provides a natural extension to a nested hierarchical model.

HIV status disclosure and antiretroviral therapy adherence among children in Masaka region, Uganda

HIV-infected children are now living into adolescence and early adulthood in large numbers due to the availability and increased use of antiretroviral therapy (ART). However, receipt of HIV status disclosure among children remains low. We assessed the association between disclosure of HIV status and adherence to ART among children in the Masaka region of Uganda using multivariable logistic regression with generalised linear models with Poisson log-link function and robust variance in Stata software version 15.1. Data were collected from 524 assenting children aged 12-17 years between March and December 2020. Results show that, although not statistically significant, children who received disclosure of their HIV status reported improved ART adherence compared to children with no disclosure. Out-of-school children with post-primary education and children on first-line ART regimens were significantly more likely to report improved ART in both crude and adjusted analyses. Innovative interventions to promote progressive disclosure of HIV status to children on ART, in school, are needed to improve their ART adherence. There is also a need to evaluate the suitability of current counselling interventions provided to children being switched to second-line ART regimens to delay the need for third-line ART regimens.

Exploring the Relationship Between Trust-Building Strategies and Public Engagement on Social Media During the COVID-19 Outbreak

Communication is critical in a new health emergency because it motivates the public to take preventive actions. Prior research has shown that strategies including source credibility, information transparency and uncertainty reduction actions could enhance trust in health communication on social media. Yet research on how the government in China used these trust-building strategies to engage the public during the outbreak of COVID-19 is limited. Therefore, our exploratory study developed an integrated framework for conducting quantitative content analysis to examine how the most popular government-owned newspaper in China, People's Daily, utilized a major social media platform, to engage the public. Our findings showed that accessibility to external links, provision of emotional support, and information on skills and resources were associated with increased public engagement with government COVID-19 posts. Insights gained can enable public health organizations and governments to focus on specific strategies to enhance public engagement.

Engaging social media users with attitudinal messages during health crisis communication

To cope with the COVID-19 pandemic, various policy measures accompanied by health crisis communication were adopted in China to engage publics. In this study, we investigated how People's Daily communicated COVID-19 messages on Weibo. Drawing on the Appraisal Framework, we developed a three-stage mixed method approach to study 400 COVID-19 posts to identify the attitude resources employed and their association with public engagement. We found that attitudinal posts were more engaging than non-attitudinal posts. Judgment, both positive and negative, was positively associated with public engagement, whereas the use of positive Affect and Appreciation could be ineffective. These findings contribute to the understanding of how public engagement on social media can be enhanced through the use of attitudinal messages in health emergencies.

Comparing two fluoride therapies for caries management in young children: study protocol for a randomised clinical trial

Background

Silver diamine fluoride (SDF) and sodium fluoride (NaF) are widely used for caries management. The objectives of this study are (i) to compare the caries-arresting and caries-preventive effects of SDF and NaF in young children, (ii) to determine children’s and parents’ acceptance of these fluoride therapies and (iii) to investigate the short-term (1 day) and long-term (1 year) adverse effects of these fluoride therapies.

Methods/design

This is a randomised, double-blind, active-controlled clinical trial to be conducted in Hong Kong kindergartens. The study has received approval from the local institutional review board. Written consent will be obtained from the parents/guardians before the study. The study will recruit at least 688 healthy 3-year-old children. This sample size is sufficient for an appropriate statistical analysis. Stratified randomisation will be performed for intervention allocation. The two intervention groups are 38% SDF and 5% NaF varnish applied on six primary upper anterior teeth. At baseline, one trained examiner will perform clinical examinations of the children in the kindergartens. The caries experience and oral hygiene status of each child will be recorded using the decayed, missing (due to caries) and filled primary tooth index and visual plaque index, respectively. Then, an independent operator will apply the assigned fluoride after the dental examinations. The examiner, the children and their parents will be blinded to the intervention allocation. In addition, a research assistant will evaluate the child’s acceptance using interval rating scales for children’s uncooperative behaviour. The examiner will then visit the children the next day to study the short-term potential adverse effects of the fluoride therapies. The same examiner will perform a follow-up examination after 1 year to evaluate the children’s caries experiences, their oral hygiene statuses and the adverse effects of the fluoride. Parental questionnaires will be used to assess parental satisfaction and concerns about the fluoride therapies.

Discussion

This study provides essential information about using SDF in an outreach kindergarten service for caries management from different aspects, which include the caries-arresting and caries-preventive effects, the adverse effects and children’s and parents’ acceptance. The success of the service can help to increase the adoption of SDF to reduce the global burden of early childhood caries.

Trial registration

ClinicalTrials.gov NCT04399369. Registered on May 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05496-y.

Impact of the dialysate acid component on haemodialysis mortality rates

BACKGROUND

No prospective study has evaluated the long-term effect on mortality of the new acid concentrates added to bicarbonate dialysate. The aim of this pharmacoepidemiological study was to evaluate the association between hydrochloric or citric acid-based dialysate and mortality on haemodialysis (HD).

METHODS

This study included 117 796 patients with 3 723 887 months on HD recorded in the national French Renal Epidemiology and Information Network registry. Dialysate acid components were retrospectively reconstructed for each facility. All patients on HD were associated each month with an exposure based on that at their facility of treatment. We took each patient's time-varying exposure into account to calculate the monthly mortality rates for each exposure. Incidence rate ratios (IRRs) for mortality were calculated with a Poisson regression, with acetic acid as the reference. Regressions were adjusted for initial clinical characteristics (age, gender, previous cardiovascular events, active malignancy, diabetes, pulmonary disease, mobility), dialysis technique and location (in-centre, outpatient centre, self-care unit) and ESRD vintage, updated monthly.

RESULTS

The crude mortality rate per 1000 patient-months with citric acid {11.5 [95% confidence interval (CI) 11.1-12.0]} was lower than with either acetic acid [12.9 (95% CI 12.8-13.1)] or hydrochloric acid [12.8 (95% CI 12.2-13.5)]. For the 2014-17 period, the IRR for mortality with citric acid [adjusted IRR 0.94 (95% CI 0.90-0.99)] and with hydrochloric acid [adjusted IRR 0.86 (95% CI 0.79-0.94)] were significantly lower than with acetic acid.

CONCLUSION

This post-marketing study of long-term exposure to dialysate acidifiers at the patient level found the use of citric and hydrochloric acid-based dialysates, compared with acetic acid, was associated with lower mortality.

The Importance of Genuineness in Public Engagement-An Exploratory Study of Pediatric Communication on Social Media in China

There is a growing need for the public to interact with pediatricians through social media in China, and genuineness is a crucial factor contributing to effective communication, but few studies have examined the relationship between genuineness and its effect on public engagement. This study developed a four-dimension framework including self-disclosure, genuine response, functional interactivity, and genuineness in Chinese culture to investigate the effect of genuineness in the communication of Chinese social media influencers in pediatrics on public engagement. Content analysis was employed to examine these dimensions and the related public engagement in 300 social media posts on the largest microblogging site in China. The findings indicate that genuine response was positively associated with the number of comments and positive comments, while negatively related to the number of shares. Functional interactivity made the site more appealing, resulting in likes and shares. Genuineness in Chinese culture was reflected in engagement through sharing posts by the public. This study is the first to develop an integrated framework to measure genuineness in online health communication and contributes to the understanding of the effect of genuineness on Chinese public engagement in social media.

Grappling With the COVID-19 Health Crisis: Content Analysis of Communication Strategies and Their Effects on Public Engagement on Social Media

Background

The coronavirus disease (COVID-19) has posed an unprecedented challenge to governments worldwide. Effective government communication of COVID-19 information with the public is of crucial importance.

Objective

We investigate how the most-read state-owned newspaper in China, People’s Daily, used an online social networking site, Sina Weibo, to communicate about COVID-19 and whether this could engage the public. The objective of this study is to develop an integrated framework to examine the content, message style, and interactive features of COVID-19–related posts and determine their effects on public engagement in the largest social media network in China.

Methods

Content analysis was employed to scrutinize 608 COVID-19 posts, and coding was performed on three main dimensions: content, message style, and interactive features. The content dimension was coded into six subdimensions: action, new evidence, reassurance, disease prevention, health care services, and uncertainty, and the style dimension was coded into the subdimensions of narrative and nonnarrative. As for interactive features, they were coded into links to external sources, use of hashtags, use of questions to solicit feedback, and use of multimedia. Public engagement was measured in the form of the number of shares, comments, and likes on the People’s Daily’s Sina Weibo account from January 20, 2020, to March 11, 2020, to reveal the association between different levels of public engagement and communication strategies. A one-way analysis of variance followed by a post-hoc Tukey test and negative binomial regression analysis were employed to generate the results.

Results

We found that although the content frames of action, new evidence, and reassurance delivered in a nonnarrative style were predominant in COVID-19 communication by the government, posts related to new evidence and a nonnarrative style were strong negative predictors of the number of shares. In terms of generating a high number of shares, it was found that disease prevention posts delivered in a narrative style were able to achieve this purpose. Additionally, an interaction effect was found between content and style. The use of a narrative style in disease prevention posts had a significant positive effect on generating comments and likes by the Chinese public, while links to external sources fostered sharing.

Conclusions

These results have implications for governments, health organizations, medical professionals, the media, and researchers on their epidemic communication to engage the public. Selecting suitable communication strategies may foster active liking and sharing of posts on social media, which in turn, might raise the public’s awareness of COVID-19 and motivate them to take preventive measures. The sharing of COVID-19 posts is particularly important because this action can reach out to a large audience, potentially helping to contain the spread of the virus.

Preventing early childhood caries with silver diamine fluoride: study protocol for a randomised clinical trial

BACKGROUND

Silver diamine fluoride (SDF) solution is effective in arresting early childhood caries (ECC). Previous studies have suggested that it might exert a preventive effect in managing ECC. However, no well-designed clinical trials have yet been performed to study the effect of SDF on caries prevention. The objective of this randomised clinical trial is to determine whether 38% SDF solution is superior to 5% sodium fluoride (NaF) varnish in preventing new carious lesions in primary anterior teeth.

METHODS/DESIGN

This is a phase II, single-centre, randomised, double-blind, active-controlled, parallel-group pragmatic trial. The hypothesis tested is that 38% SDF would be more effective than 5% NaF in preventing new caries development in primary anterior teeth. Approximately 730 3-year-old children who are generally healthy and with parental consent will be recruited from Hong Kong kindergartens. This sample size will be sufficient for appropriate statistical analysis of a superiority trial with 90% power, allowing for a 20% drop-out rate. Stratified randomisation will be adopted for allocating the intervention. The intervention will either be 38% SDF or 5% NaF (as a positive control) therapy on primary upper anterior teeth. A single trained examiner will conduct a dental examination every 6 months until 30 months in kindergarten. Another operator will provide fluoride therapy immediately after each dental examination. The examiner, children and children's parents will be blinded to the treatment allocation. A questionnaire survey will be conducted to study the children's oral health-related behaviours and socioeconomic backgrounds. Chi-square tests, t tests, regression analyses and survival analyses will be adopted for data analysis.

DISCUSSION

The effectiveness of 38% SDF in preventing ECC remains uncertain. If the results are as anticipated, care standards using 5% NaF for ECC prevention will be changed. In addition, the results will be widely available and increase the adoption of SDF in other countries to reduce the global burden of ECC.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04075474. Registered on 30 Aug 2019.

Early childhood caries among 3- to 5-year-old children in Hong Kong

OBJECTIVE

The aim of this study was to describe the prevalence of dental caries among 3- to 5-year-old children in Hong Kong and to investigate the factors associated with their dental caries status.

METHODS

Seven kindergartens in Hong Kong were selected using stratified random sampling. The 3- to 5-year-old kindergarten children were invited to join the study. The participants' parents were asked to complete a questionnaire regarding their children's demographic and socio-economic backgrounds, their dental habits and their own dental knowledge. Dental caries experience was measured using the decayed, missing and filled primary teeth (dmft) index. The visible plaque index was adopted for recording oral hygiene. The relationships between caries experience and children's demographic backgrounds, dental habits, oral hygiene and parental dental knowledge were studied using a zero-inflated negative binomial (ZINB) regression analysis.

RESULTS

Among the 1,204 participating preschool children, the overall prevalence of dental caries (dmft > 0) was 46%. The mean dmft score was 2.1 ± 3.4. The prevalences of dental caries among the 3-, 4- and 5-year-old children were 38%, 43% and 55%, respectively. ZINB regression analysis revealed that the study children who were boys, came from families with lower incomes, had dental visit experiences, had higher plaque scores and had parents with lower levels of dental knowledge, had higher dmft scores (P < 0.05).

CONCLUSIONS

Dental caries is prevalent among preschool children in Hong Kong. The caries experiences of the study children are associated with gender, family income, parental dental knowledge, dental visit experience and oral hygiene.