The protective effect of CALD identity in the presence of low income on missing teeth of Australian adults over time.

BACKGROUND: 'Culturally And Linguistically Diverse (CALD)' populations have diverse languages, ethnic backgrounds, societal structures and religions. CALD populations have not experienced the same oral health benefits as non-CALD groups in Australia. However, the socio-demographic profile of Australian CALD populations is changing. This study examined how household income modifies the oral health of CALD and non-CALD adults in Australia. METHODS: Data were from two National Surveys of Adult Oral Health (NSAOH) conducted in 2004-06 (NSAOH 2004-06) and 2017-18 (NSAOH 2017-18). The outcome was self-reported number of missing teeth. CALD status was identified based on English not the primary language spoken at home and country of birth not being Australia. Social disadvantage was defined by total annual household income. Effect-measure modification was used to verify differences on effect sizes per strata of CALD status and household income. The presence of modification was indicated by Relative Excess Risk due to Interactions (RERIs). RESULTS: A total of 14,123 participants took part in NSAOH 2004-06. The proportion identifying as CALD was 11.7% and 56.7% were in the low-income group, and the mean number of missing teeth was 6.9. A total of 15,731 participants took part in NSAOH 2017-18. The proportion identifying as CALD was 18.5% and 38.0% were in the low-income group, and the mean number of missing teeth was 6.2. In multivariable modelling, the mean ratio (MR) for CALD participants with low household income in 2004-06 was 2% lower than the MR among non-CALD participants with high household income, with the RERI being - 0.23. Non-CALD participants from lower income households had a higher risk of having a higher number of missing teeth than low income CALD individuals (MR = 1.66, 95%CI 1.57-1.74 vs. MR = 1.43 95%CI 1.34-1.52, respectively). In 2017-18, the MR for CALD participants with low household income was 3% lower than the MR among non-CALD participants with high household income, with the RERI being - 0.11. Low income CALD participants had a lower risk of missing teeth compared to their non-CALD counterparts (MR = 1.43, 95% CI 1.34-1.52 vs. MR = 1.57, 95% CI 1.50-1.64). CONCLUSIONS: The negative RERI values indicate that the effect-measure modification operates in a negative direction, that is, there is a protective element to being CALD among low income groups with respect to mean number of missing teeth.

Screen Time and Parent-Child Talk When Children Are Aged 12 to 36 Months.

Importance: Growing up in a language-rich home environment is important for children's language development in the early years. The concept of "technoference" (technology-based interference) suggests that screen time may be interfering with opportunities for talk and interactions between parent and child; however, limited longitudinal evidence exists exploring this association. Objective: To investigate the longitudinal association between screen time and 3 measures of parent-child talk (adult words, child vocalizations, and conversational turns) when children are 12 to 36 months of age. Design, Setting, and Participants: This Australian prospective cohort study used advanced speech recognition technology to capture young children's screen time and home language environment, on an average 16-hour day. Data were collected from 220 families once every 6 months in the family home when children were 12, 18, 24, 30, and 36 months of age, from January 1, 2018, to December 31, 2021. Statistical analysis took place from November 1, 2022, to July 31, 2023. Exposure: Language Environment Analysis (LENA) technology provided automated counts of children's language environment and exposure to electronic noise. The exposure of interest was screen time, which was calculated based on manual coding of LENA electronic noise audio segments. Main Outcomes and Measures: Three measures of parent-child talk were outcomes of focus: adult words, child vocalizations, and conversational turns. Separate models were run for each of the 3 outcomes and included adjustment for child sex, child age, maternal educational level, number of children at home, number of home activities, and primary caregiver's psychological distress. Results: The study included 220 families (120 girls [54.6%]; mean [SD] gestational age of children, 39.3 [1.5] weeks; mean [SD] age of mother at childbirth, 31.3 [4.8] years). Adjusted linear mixed-effect models demonstrated that increases in screen time were associated with decreases in measures of parent-child talk. The largest decreases were seen at 36 months, when an additional minute of screen time was associated with a reduction of 6.6 (95% CI, -11.7 to -1.5) adult words, 4.9 (95% CI, -6.1 to -3.7) child vocalizations, and 1.1 (95% CI, -1.4 to -0.8) conversational turns. Conclusion and Relevance: Findings of this study support the notion of technoference for Australian families, whereby young children's exposure to screen time is interfering with opportunities to talk and interact in their home environment. This finding has implications for interventions and supports aimed at promoting a language-rich home environment, with families needing support in understanding the potential association of screen time with opportunities for children and adults to talk and interact in their home environment.

The Mouth as a Site of Compound Injustices: A Structural Intersectionality Approach to the Oral Health of Working-Age US Adults.

Knowledge of and practice around health inequities have been limited by scarce investigations on intersecting forms of structural oppression, including the extent to which their effects are more severe among multiply marginalized groups. We addressed these insufficiencies by adopting a structural intersectionality approach to the study of edentulism (i.e., complete tooth loss), the dental equivalent of mortality. While individual information was gathered from approximately 200,000 adult (ages 18-64 years) respondents to the 2010 US Behavioral Risk Factor Surveillance System survey, state-level data for 2000 and 2010 were obtained from a 2021 study by Homan et al. (J Health Soc Behav. 2021;62(3):350-370) and the US Census. These 3 sources provided information on edentulism, race, sex, structural racism, structural sexism, and income inequality, in addition to multiple covariates. Analyses showed that the intersections between structural sexism and state-level income inequality and structural racism were associated with 1.4 (95% confidence interval: 1.1, 1.9) and 1.5 (95% confidence interval: 1.1, 2.2) times' increased odds of complete tooth loss, respectively. The frequency of edentulism was highest among non-Hispanic Black men residing in states with high structural racism, high structural sexism, and high economic inequality. Based on these and other findings, we highlight the importance of a structural intersectionality approach to research and policy related to health inequities in the United States and elsewhere.

Is the Association between Age and Fertility Problems Modified by Diet Quality? Findings from a National Study of Reproductive Age Women in Australia.

Background: Increasing age is a strong risk factor for infertility, and there is accumulating evidence of the importance of a healthier diet for fertility. Whether a healthier diet modifies the association between increasing age and infertility has not been investigated. This study aimed to (i) examine if better diet quality could help reduce age-related infertility; and (ii) assess whether changes in diet quality over time are associated with fertility problems. Methods: Data were from Surveys 3 and 5 of the 1973−1978 birth cohort of the Australian Longitudinal Study on Women's Health. Cross-sectional analysis with multivariable generalized linear models were used to examine the association between age and fertility status, adjusted for various confounders. Multiplicative and additive effect modification by diet quality was assessed, with additive effect modification evaluated with the relative risk for interaction (RERI). Results: In total, 3387 women were included from Survey 3 (age range 24−31 years) and 5614 women from Survey 5 (age range 30−38 years); 588 (17.4%) and 1321 (23.4%) self-reported to have fertility problems in the respective surveys. In Survey 3, compared to younger women with a good-quality diet, older women with a poor-quality diet had a 43% increased risk for fertility problems, with risk increasing after further adjustment for BMI (RR: 1.59; 95% CI: 1.07, 2.37) and PCOS (RR: 1.74; 95% CI: 1.15, 2.62). In Survey 5 in younger women (<33.9 years), there was no association between diet quality and risk for infertility problems. The RERI (across different adjusted models) was between −0.08 (−0.70, 0.55) to −0.39 (−1.40, 0.62) in survey 3 and 0.07 (−0.17, 0.31) to 0.08 (−0.17, 0.32) in Survey 5. Conclusions: There is little evidence to suggest effect modification on the effect of age and fertility problems with diet quality.

How do state-level racism, sexism, and income inequality shape edentulism-related racial inequities in contemporary United States? A structural intersectionality approach to population oral health.

OBJECTIVE: Research on racial oral health inequities has relied on individual-level data with the premise being that the unequal distribution of dental diseases is an intractable problem. We address these insufficiencies by examining the relationships between structural racism, structural sexism, state-level income inequality, and edentulism-related racial inequities according to a structural intersectionality approach. METHODS: Data were from two sources, the 2010 survey of the U.S. Behavioral Risk Factor Surveillance System, and Patricia Homan et al.'s (2021) study on the health impacts from interlocking systems of oppression. While the first contains information on edentulism from a large probabilistic sample of older (65+) respondents, the second provides estimates of racism, sexism, and income inequality across the US states. Taking into account a range of individual characteristics and contextual factors in multilevel models, we determine the extent to which structural forms of marginalization underlie racial inequities in edentulism. RESULTS: Our analysis reveals that structural racism, structural sexism, and state-level income inequality are associated with the overall frequency of edentulism and the magnitude of edentulism-related racial inequities, both individually and intersectionally. Coupled with living in states with both high racism and sexism (but not income inequality), the odds of edentulism were 60% higher among non-Hispanic Blacks, relative to Whites residing where these structural oppressions were at their lowest. CONCLUSIONS: These findings provide evidence that racial oral health inequities cannot be disentangled from social forces that differentially allocate power and resources among population groups. Mitigating race-based inequities in oral health entails dismantling the multifaceted systems of oppression in the contemporary U.S. society.

Where are race-based oral health inequities bound? Protocol for a systematic review on interventions to tackle racial injustice in dental outcomes.

BACKGROUND: Only three literature reviews have assessed the impact of interventions on the reduction of racial inequities in general health to date; none has drawn from attempts at promoting racial oral health equity. This protocol aims to increase transparency and reduce the potential for bias of an ongoing systematic review conceived to answer the following questions: Are there any interventions to mitigate racial oral health inequities or improve the oral health of racially marginalized groups? If so, how successful have they been at promoting racial oral health equity? How do conclusions of previous reviews change by taking the findings of oral health interventions into account? METHODS: Reviewed studies must deploy interventions to reduce racial gaps or promote the oral health of groups oppressed along ancestral and/or cultural lines. We will analyze randomized clinical trials, natural experiments, pre-post studies, and observational investigations that emulate controlled experiments by assessing interactions between race and potentially health-enhancing interventions. Either clinically assessed or self-reported oral health outcomes will be considered by searching for original studies in MEDLINE, LILACS, PsycInfo, SciELO, Web of Science, Scopus, and Embase from their earliest records to March 2022. Upon examining abstracts of conference proceedings, trial registries, reports of related stakeholder organizations, as well as contacting researchers for unpublished data, we will identify studies in the grey literature. If possible, we will carry out a meta-analysis with subgroup and sensitivity analysis, including formal meta-regression, to address potential heterogeneity and inconsistency among selected studies. DISCUSSION: Conducting a systematic review of interventions to mitigate racial oral health inequities is crucial for determining which initiatives work best and under which conditions they succeed. Such knowledge will help consolidate an evidence base that may be used to inform policy and practice against persistent and pervasive racial inequities in general and oral health. SYSTEMATIC REVIEW REGISTRATION: This protocol has been registered at the International Prospective Register of Systematic Reviews, under the identification number CRD42021261450 .

Is the association between social support and oral health modified by household income? Findings from a national study of adults in Australia.

OBJECTIVE: To investigate whether the association between social support and oral health outcomes is modified by levels of household income. METHODS: Data were from the National Study of Adults Oral Health (NSAOH 2004-06), a nationally representative study comprising n = 3619 adults in Australia. Effect measure modification (EMM) analysis was adopted to verify whether the association between social support and poor/fair self-rated oral health, lack of a functional dentition (<21 teeth) and low Oral Health Related Quality of Life (OHRQoL; measured using OHIP-14) varies according to levels of income. Poisson regressions adjusted for age, sex, education, country of birth, main language spoken at home and remoteness were used to estimate prevalence ratios (PR) for oral health outcomes for each stratum of social support (overall, family, friends and significant other) and income (effect modifier). We then computed the Relative Excess Risk due to Interaction (RERI), which represents the risk that is over what would be expected if the combination of low social support and low income was entirely additive. Sensitivity analyses for different cut-offs of household income were performed. RESULTS: Adults with lower levels of social support had a 2.1, 1.2 and 1.9 times higher prevalence of fair/poor self-rated oral health, <21 teeth and poor OHRQoL respectively. The RERIs observed were 0.98 (95% CI -0.01; 1.96) for poor/fair self-rated oral health; 0.52 (95% CI -0.06; 1.10) for lack of a functional dentition and 0.50 (95% CI -0.16; 1.15) for poor OHRQoL. For all outcomes and all individual domains of social support, the positive RERIs indicated that the joint association of low social support and low household income surpassed the sum of their separate associations with objective and subjective oral health indicators. CONCLUSION: Individuals with lower levels of social support had poorer oral health than those with high levels of social support, although this association was small for the outcome <21 teeth. The association between social support and poor oral health indicators is modified by levels of household income. Hence, the provision of social support had a stronger association with the oral health of low-income participants, suggesting that socioeconomically disadvantaged individuals would mostly benefit from a social support intervention.

The independent and joint contribution of objective and subjective socioeconomic status on oral health indicators.

OBJECTIVES: The understanding of how subjective socioeconomic status (SSS) relates to objective socioeconomic status (OSS), and how both conditions act together in oral health outcomes is still unclear. This study aims to test the independent and joint association between OSS and SSS with oral health, to assess the role of socioeconomic status discrepancies, and to evaluate the role of SSS in the association between OSS and oral health. METHODS: Data from 1140 adults from a population-based study in Southern Brazil were used. We applied diagonal reference models DRM to disentangle the effects of OSS (education) and SSS (MacArthur Scale) to oral health outcomes. The outcomes were functional dentition clinically evaluated (FD ≥20 teeth) and self-reported oral health SROH. We also examined the discrepancy between OSS and SSS to oral health indicators and the effect measure modification (EMM) of SSS on the association between OSS and oral health. RESULTS: Subjective socioeconomic status and OSS contributed equally to SROH, while OSS explained a substantially higher amount of FD than SSS (0.85 vs 0.15). An EMM of SSS was found on the association between OSS and fair/poor SROH, with a relative excess risk due to interaction (RERI) of 1.08. Less evidence of EMM was found for FD (RERI = 0.14). Individuals with lower SSS and OSS had four times the risk of the outcomes than the reference group. CONCLUSIONS: Adults with concordant lower SSS and OSS have a worse oral health than those with concordant higher status. There was evidence that the association between OSS and SROH is modified by SSS.

Cohort profile: South Australian Aboriginal Birth Cohort (SAABC)-a prospective longitudinal birth cohort.

PURPOSE: The South Australian Aboriginal Birth Cohort (SAABC) is a prospective, longitudinal birth cohort established to: (1) estimate Aboriginal child dental disease compared with population estimates; (2) determine the efficacy of an early childhood caries intervention in early versus late infancy; (3) examine if efficacy was sustained over time and; (4) document factors influencing social, behavioural, cognitive, anthropometric, dietary and educational attainment over time. PARTICIPANTS: The original SAABC comprised 449 women pregnant with an Aboriginal child recruited February 2011 to May 2012. At child age 2 years, 324 (74%) participants were retained, at age 3 years, 324 (74%) participants were retained and at age 5 years, 299 (69%) participants were retained. Fieldwork for follow-up at age 7 years is underway, with funding available for follow-up at age 9 years. FINDINGS TO DATE: At baseline, 53% of mothers were aged 14-24 years and 72% had high school or less educational attainment. At age 3 years, dental disease experience was higher among children exposed to the intervention later rather than earlier in infancy. The effect was sustained at age 5 years, but rates were still higher than general child population estimates. Experiences of racism were high among mothers, with impacts on both tooth brushing and toothache. Compared with population estimates, levels of self-efficacy and self-rated oral health of mothers at baseline were low. FUTURE PLANS: Our data have contributed to a better understanding of the environmental, behavioural, dietary, biological and psychosocial factors contributing to Aboriginal child oral and general health, and social and emotional well-being. This is beneficial in charting the trajectory of cohort participants' health and well-being overtime, particularly in identifying antecedents of chronic diseases which are highly prevalent among Aboriginal Australians. Funding for continued follow-up of the cohort will be sought. TRIAL REGISTRATION NUMBER: ACTRN12611000111976; Post-results.

Intersectionality, racial discrimination and oral health in Australia.

BACKGROUND: There is a dearth of studies on the extent to which perceived racial discrimination shapes oral health. Following an intersectional perspective, we estimated the prevalence of perceived racial discrimination in Australia, its association with oral health impairment, and examined whether this association was more severe among low socioeconomic status (SES) groups. METHODS: Data came from the 2013 National Dental Telephone Interview Survey (N = 2798), a population-based study of Australian adults. Multivariable Poisson regression models were estimated to test the relationship between perceived racial discrimination and self-reported oral health impairment, as well as to investigate whether the magnitude of this association was greater among low-SES respondents. Relative Excess Risks due to Interaction (RERI) were used to indicate the presence of potentially large discrimination effects within low-SES strata. RESULTS: Racial discrimination in the past 12 months was reported by 11.5% of all participants. Australians reporting racial discrimination had 1.4 (95% CI 1.1, 1.7) times the prevalence of impaired oral health. The association between perceived racial discrimination and oral health impairment was stronger among low-SES groups. The RERI was 0.55, indicating a super-additive Effect Measure Modification (EMM) by income on the additive scale. Similar results were observed with the EMM analyses by educational attainment. CONCLUSION: Our findings indicate that perceived racial discrimination, as a specific form of widespread inequality, is associated with higher frequencies of oral health impairment among Australian adults. We also suggest that socially marginalized groups bear a greater burden of the oral health effects of racial discrimination.

Comparison of the Tree-Based Machine Learning Algorithms to Cox Regression in Predicting the Survival of Oral and Pharyngeal Cancers: Analyses Based on SEER Database.

This study aims to demonstrate the use of the tree-based machine learning algorithms to predict the 3- and 5-year disease-specific survival of oral and pharyngeal cancers (OPCs) and compare their performance with the traditional Cox regression. A total of 21,154 individuals diagnosed with OPCs between 2004 and 2009 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Three tree-based machine learning algorithms (survival tree (ST), random forest (RF) and conditional inference forest (CF)), together with a reference technique (Cox proportional hazard models (Cox)), were used to develop the survival prediction models. To handle the missing values in predictors, we applied the substantive model compatible version of the fully conditional specification imputation approach to the Cox model, whereas we used RF to impute missing data for the ST, RF and CF models. For internal validation, we used 10-fold cross-validation with 50 iterations in the model development datasets. Following this, model performance was evaluated using the C-index, integrated Brier score (IBS) and calibration curves in the test datasets. For predicting the 3-year survival of OPCs with the complete cases, the C-index in the development sets were 0.77 (0.77, 0.77), 0.70 (0.70, 0.70), 0.83 (0.83, 0.84) and 0.83 (0.83, 0.86) for Cox, ST, RF and CF, respectively. Similar results were observed in the 5-year survival prediction models, with C-index for Cox, ST, RF and CF being 0.76 (0.76, 0.76), 0.69 (0.69, 0.70), 0.83 (0.83, 0.83) and 0.85 (0.84, 0.86), respectively, in development datasets. The prediction error curves based on IBS showed a similar pattern for these models. The predictive performance remained unchanged in the analyses with imputed data. Additionally, a free web-based calculator was developed for potential clinical use. In conclusion, compared to Cox regression, ST had a lower and RF and CF had a higher predictive accuracy in predicting the 3- and 5-year OPCs survival using SEER data. The RF and CF algorithms provide non-parametric alternatives to Cox regression to be of clinical use for estimating the survival probability of OPCs patients.

Advancing racial equity in oral health (research): more of the same is not enough.

By critically appraising the literature on the oral health effects of race-based oppression, this focus article makes four recommendations that may both facilitate more nuanced research on the topic and mitigate racial/ethnic inequities in (oral) health. The first is recognizing that science itself may perpetuate racial/ethnic injustice, such that adopting a 'neutral' position must be replaced with actively fostering anti-racist narratives. The second is to not imply that racial oppression is bad because it harms oral health. Rather, studies should help build a fairer world, wherein oral health inequities would not abound. The third recommendation is encouraging initiatives that understand systems of oppression as conjointly operating to shape oral health. The fourth and final recommendation is taking race-based oppression as a multi-level system that operates on three inter-related conceptual levels - intra-personal, inter-personal, and structural. The extent to which scholars, practitioners, and policymakers are willing to follow these recommendations may determine how successful attempts to eradicate (oral) health inequities might be. Learning from, and avoiding mistakes made in, previous publications is one ethical pathway towards this end.

Educational activities on language and behavioural outcomes at school entry are more important for socioeconomically disadvantaged children: a prospective observational study of Australian children.

BACKGROUND: To investigate whether time spent in educational activities at 2-3 years and developmental outcomes at school entry differ among children from different socioeconomic backgrounds. METHODS: Participants were from the Longitudinal Study of Australian Children (n=4253). Time spent in educational activities was collected using 24-hour time-use diaries. Income was measured using parent self-report. Receptive vocabulary was assessed using the Peabody Picture Vocabulary Test, and problem behaviours were measured by the Strengths and Difficulties Questionnaire. Marginal structural models were used to test whether the effects of educational activities on outcomes differed by income. RESULTS: Children exposed to both <30 min/day in educational activities and being in a low-income household were at greater risk of poorer outcomes at school entry than the simple sum of their independent effects. Compared with children who spent ≥30 min/day in educational activities from high-income households, children who experienced <30 min/day in educational activities from low-income households had a 2.30 (95% CI 1.88 to 2.80) higher risk of having a receptive vocabulary score in the lowest quartile at school entry. The Relative Excess Risk due to Interaction of 0.15 (95% CI -0.38 to 0.67) was greater than 0, indicating a super-additive effect measure modification by income. These patterns were similar for behavioural outcomes. CONCLUSIONS: Our findings suggest that if there was an intervention of sufficient dose to increase the amount of time spent in educational activities to at least 30 min/day for children in the lower-income group, the risk of children having sub-optimal receptive vocabulary would be reduced by 45% and the risk of teacher-reported conduct and hyperactivity problems reduced by 67% and 70%, respectively.

Oral health impacts among Australian adults in the National Study of Adult Oral Health (NSAOH) 2017-18.

BACKGROUND: This paper examines oral health impacts of toothache experience, self-rated oral health (SROH), being uncomfortable with dental appearance, and avoiding foods in the Australian adult population. METHODS: The explanatory variables include age, sex, region, income, area-based SES, dental insurance and visiting pattern. The data were collected in the interview in NSAOH 2017-18. RESULTS: There were lower percentages with: toothache in the highest (14.8%) than middle (21.2%) and lower income tertiles (25.2%); fair/poor SROH in the highest (15.8%) than middle (24.1%) and lower tertiles (34.8%); uncomfortable with appearance in the highest (29.1%) than middle (35.3%) and lower tertiles (42.2%); and food avoidance in the higher (15.3%) than middle (22.9%) and lower tertiles (34.4%). There were higher percentages with: toothache in the unfavourable (32.2%) than intermediate (23.1%) and favourable (11.7%) visiting groups; fair/poor SROH in the unfavourable (44.0%) than intermediate (27.4%) or favourable (10.2%) groups; being uncomfortable about appearance in the unfavourable (47.6%) than intermediate (39.5%) or favourable (25.8%) groups; and avoiding foods in the unfavourable (34.8%) than intermediate (26.0%) or favourable (14.5%) groups. CONCLUSIONS: Socioeconomic status and dental visiting were associated with oral health impacts. Oral health impacts were worse for those with lower income and unfavourable visiting patterns.

Which time investments in the first 5 years of life matter most for children's language and behavioural outcomes at school entry?

BACKGROUND: The ways children spend their time is one of the most valuable inputs for healthy child development. It is unknown which time investment yields the greatest return for children's language and behavioural outcomes at school entry. METHODS: We used data from the first three waves (2004, 2006, 2008) of the Longitudinal Study of Australian Children (n = 4253). At every wave, parents completed 24-h time-use diaries on one randomly selected week and one weekend day. The amount of time children spent on 11 activities at ages 0-1, 2-3 and 4-5 years was analysed. Receptive vocabulary was assessed using the Peabody Picture Vocabulary Test, and externalizing behaviours were measured by the Strengths and Difficulties Questionnaire, completed by parents and teachers at 4-5 years. To identify which time investment in the first 5 years of life mattered most for children's outcomes, a new production function was developed. This production function was estimated using a log-log linear regression model. RESULTS: Relative to other time investments, time spent on educational activities at 2-3 years of age was the most important time investment for receptive vocabulary and behavioural outcomes at school entry. After adjusting for confounding, every 1 h invested in educational activities at 2-3 years was associated with a 0.95% [95% CI (confidence interval): 0.62, 1.28] increase in receptive vocabulary, and a -5.72% (95% CI: -7.71, -3.73) and -9.23% (95% CI: -12.26, -6.20) reduction in parent- and teacher-reported externalizing problem behaviours. Time invested in play was also important to both receptive vocabulary and behaviour. One hour invested in play at 2-3 and 4-5 years was associated with a 0.68% (95% CI: 0.38, 0.98) and 0.71% (95% CI: 0.39, 1.03) increase in children's receptive vocabulary at school entry. In addition, time invested in play at 2-3 and 4-5 years was associated with reduced problem behaviours at school entry. In contrast, screen time at all ages was associated with poorer parent- and teacher-reported externalizing problem behaviours. CONCLUSIONS: These results suggest that time invested in educational activities at 2-3 years of age yield the greatest return for children's receptive vocabulary and behaviour at school entry.

Is There an Association between Breastfeeding and Dental Caries among Three-Year-Old Australian Aboriginal Children?

An unresolved question about breastfeeding is its effect on caries, in particular, early childhood caries (ECC). In secondary analyses of data from an ECC intervention, we describe breastfeeding among Aboriginal children and associations between breastfeeding and ECC. Breastfeeding (duration and exclusivity to six months) was grouped into mutually exclusive categories. ECC was observed by a calibrated dental professional. Outcomes were prevalence of ECC (% decayed, missing, and filled teeth in the primary dentition (% dmft>0)) and caries severity (mean number of decayed, missing, and filled surfaces (mean dmfs)) in children aged three years. Analyses were adjusted for confounding. Multiple imputation was undertaken for missing information. Of 307 participants, 29.3% were never breastfed, 17.9% exclusively breastfed to six months, and 9.3% breastfed >24 months. Breastfeeding >24 months was associated with higher caries prevalence (adjusted prevalence ratio (PRa) 2.06 (95%CI 1.35, 3.13, p-value = 0.001) and mean dmfs (5.22 (95% CI 2.06, 8.38, p-value = 0.001), compared with children never breastfed. Exclusive breastfeeding to six months with breastfeeding <24 months was associated with 1.45 higher caries prevalence (95% CI -0.92, 2.30, p-value = 0.114) and mean dmfs 2.04 (-0.62, 4.71, p-value = 0.132), compared with never breastfeeding. The findings are similar to observational studies on breastfeeding and caries but not with randomized controlled trials of breastfeeding interventions. Despite attending to potential biases, inconsistencies with trial evidence raises concerns about the ability to identify causal effects of breastfeeding in observational research.

Does ethnic-racial identity modify the effects of racism on the social and emotional wellbeing of Aboriginal Australian children?

OBJECTIVES: This study investigates the protective role of ethnic-racial identity (ERI) affirmation on the longitudinal association between racism and Aboriginal Australian children's social and emotional well-being (SEWB). METHODS: 408 children from the K-Cohort of the Longitudinal Study of Indigenous Children were included in the analysis. Data were collected through questionnaire-guided interviews at 7-10 and 9-12 years of age. Children's racism experience, SEWB (Strengths and Difficulties Questionnaire), and confounding were reported by caregivers. ERI was reported by children and dichotomized into high versus low. Generalized linear models with log-Poisson links and robust errors were used to estimate adjusted Risk Ratios (RRa) for the effect of racism on SEWB domains. Effect-measure modification analysis was used to verify differences on effect sizes per strata of ERI affirmation. The presence of modification was indicated by the Relative Excess Risk due to Interaction (RERI). RESULTS: Slightly above half (51.4%) of the children presented high ERI affirmation. Children exposed to racism and with low ERI affirmation were at increased risk of hyperactive behavior (RRa 2.53, 95% CI 1.17, 5.48), conduct problems (RRa 2.35, 95% CI 1.07, 5.15), and total difficulties (RRa 1.73, 95% CI 0.84, 3.55). Positive RERIs indicated the joint effects of racism and low ERI affirmation surpassed the sum of their separate effects in these domains. Children with high ERI affirmation were at increased risk of peer problems (RRa 1.66, 95% CI 0.78, 3.52). CONCLUSIONS: These findings suggest that ERI may mitigate the risk of poor SEWB due to racism. Fostering affirmative ERI can be an important strategy in promoting resilience in Aboriginal Australian children.

Food advertising on Australian television: Frequency, duration and monthly pattern of advertising from a commercial network (four channels) for the entire 2016.

AIM: To estimate the frequency, duration and monthly pattern of discretionary food advertising on Australian free-to-air television. METHODS: We logged 30 000 h of television collected in Adelaide during 2016 from one network that has four channels. The Australian Guide to Healthy Eating was used to identify discretionary foods. Data were examined according to all times, to children's peak viewing times (PVTs) and to when C-(children's) rated programmes may be broadcast. RESULTS: Of the >800 000 advertisements logged during 2016, 11% were for foods (n = 97 837). The most frequently advertised products were: snack foods (e.g. crisps), crumbed/battered meats, fast foods/take away meals and sweetened beverages. The frequency and duration of discretionary food advertising was 1.7 times/h and 0.5 min/h respectively at all times. During children's PVTs, the frequency and duration of discretionary food advertising was 2.3 times/h and 0.7 min/h, respectively. When C-rated programmes can be broadcast, the frequency and duration of discretionary food advertising was 1.8 times/h and 0.6 min/h, respectively. Across the year, discretionary foods ranged between 41% (August) and 71% (January) of all food advertising. CONCLUSIONS: Discretionary foods dominate food advertising. On average, discretionary food advertising was higher during PVTs for children and during the summer school holidays (January).

The magnitude of Indigenous and non-Indigenous oral health inequalities in Brazil, New Zealand and Australia.

OBJECTIVE: To compare the magnitude of relative oral health inequalities between Indigenous and non-Indigenous persons from Brazil, New Zealand and Australia. METHODS: Data were from surveys in Brazil (2010), New Zealand (2009) and Australia (2004-06 and 2012). Participants were aged 35-44 years and 65-74 years. Indigenous and non-Indigenous inequalities were estimated by prevalence ratios (PR) and their corresponding 95% confidence intervals (CI), adjusting for sex, age and income. Outcomes included inadequate dentition, untreated dental caries, periodontal disease and the prevalence of "fair" or "poor" self-rated oral health in Australia and New Zealand, and satisfaction with mouth/teeth in Brazil (SROH). RESULTS: Irrespective of country, Indigenous persons had worse oral health than their non-Indigenous counterparts in all indicators. The magnitude of these ratios was greatest among Indigenous and non-Indigenous Australians, who, after adjustments, had 2.77 times the prevalence of untreated dental caries (95% CI 1.76, 4.37), 5.14 times the prevalence of fair/poor SROH (95% CI 2.53, 10.43). CONCLUSION: Indigenous people had poorer oral health than their non-Indigenous counterparts, regardless of setting. The magnitude of the relative inequalities was greatest among Indigenous Australians for untreated dental decay and poor SROH.