Vitamin A supplementation coverage and associated factors for children aged 6 to 59 months in integrated and campaign-based delivery systems in four sub-Saharan African countries.

BACKGROUND: Vitamin A deficiency (VAD) is a leading contributor to the poor health and nutrition of young children in sub-Saharan Africa. Funding constraints are compelling many countries to shift from longstanding campaigns to integrating vitamin A supplementation (VAS) into routine health services. We assessed child VAS coverage and associated factors for integrated delivery systems in Mozambique, Senegal, and Sierra Leone and for a campaign-based delivery strategy in Tanzania. METHODS: Data were obtained using representative household surveys administered to primary caregivers of N = 16,343 children aged 6-59 months (Mozambique: N = 1,659; Senegal: N = 7,254; Sierra Leone: N = 4,149; Tanzania: N = 3,281). Single-dose VAS coverage was assessed and bivariate and multivariable associations were examined for child VAS receipt with respect to rural or urban residence; child age and sex; maternal age, education, and VAS program knowledge; and household wealth. RESULTS: VAS coverage for children aged 6-59 months was 42.8% (95% CI: 40.2, 45.6) in Mozambique, 46.1% (95% CI: 44.9, 47.4) in Senegal, 86.9% (95% CI: 85.8, 87.9) in Sierra Leone, and 42.4% (95% CI: 40.2, 44.6) in Tanzania and was significantly higher for children 6-11 vs. 24-59 months in Mozambique, Senegal, and Tanzania. In Sierra Leone, children aged 12-23 months (aOR = 1.86; 95% CI: 1.20, 2.86) and 24-59 months (aOR = 1.55; 95% CI: 1.07, 2.25) were more likely to receive VAS, compared to those 6-11 months. Maternal awareness of VAS programs was associated with higher uptake in Mozambique (aOR = 4.00; 95% CI: 2.81, 5.68), Senegal (aOR = 2.72; 95% CI: 2.35, 3.15), and Tanzania (aOR = 14.50; 95% CI: 10.98, 19.17). Increased household wealth was associated with a higher likelihood of child VAS in Senegal and Tanzania. CONCLUSIONS: Our findings indicate routine delivery approaches for VAS are not achieving the level of coverage needed for public health impact in these settings. Intensive outreach efforts contributed to the higher coverage in Sierra Leone and highlight the importance of reducing the burdens associated with seeking supplementation at health facilities. As countries move towards incorporating VAS into routine health services, the essentiality of informed communities and potential losses for older children and socio-economically disadvantaged populations are key considerations in the sub-Saharan African context.

Dietary Quality and Associated Factors among Women of Reproductive Age in Six Sub-Saharan African Countries.

The burden of micronutrient malnutrition is high among women of reproductive age (WRA) in sub-Saharan Africa. We examined the dietary quality and associated factors for WRA in Cameroon, Côte d'Ivoire, Kenya, Nigeria, Senegal, and Tanzania. Data were collected from women aged 15-49 years using representative Diet Quality Questionnaire surveys. The Minimum Dietary Diversity for Women (MDD-W), All-5 (key food group) consumption, noncommunicable disease risk (NCD-Risk), and Global Dietary Recommendation (GDR) indicators were assessed. Participants included N = 16,584 women [Cameroon: N = 2073; Côte d'Ivoire: N = 242; Kenya: N = 864; Adamawa State (Nigeria): N = 1283; Benue State (Nigeria): N = 1047; Nasarawa State (Nigeria): N = 1151; Senegal: N = 7232; Tanzania: N = 2692]. The MDD-W ranged from 43.0% in Tanzania to 81.4% in Côte d'Ivoire and was higher in urban, compared to rural, areas in Cameroon, Kenya, Nasarawa, Senegal, and Tanzania (p < 0.001). Increased education and wealth were positively associated with MDD-W in Kenya, Benue, Senegal, and Tanzania. Fewer than half of all women attained All-5 consumption. NCD-Risk scores ranged from 1.13 (95% CI: 1.08, 1.17) in Tanzania to 2.28 (95% CI: 2.16, 2.40) in Nasarawa, and women's GDR scores ranged from 10.47 (95% CI: 10.40, 10.54) in Cameroon to 11.45 (95% CI: 11.25, 11.64) in Côte d'Ivoire. Our findings highlight key aspects of women's diets in sub-Saharan African settings to enable greater awareness and more targeted responses to the specific areas needing the most improvement.

Feasibility of delivering vitamin A supplementation (VAS) and deworming through routine community health services in Siaya County, Kenya: A cross-sectional study.

Vitamin A deficiency and soil-transmitted helminth infection are serious public health problems in Kenya. The coverage of vitamin A supplementation and deworming medication (VASD) provided through mass campaigns is generally high, yet with a cost that is not sustainable, while coverage offered through routine health services is low. Alternative strategies are needed that achieve the recommended coverage of >80% of children twice annually and can be managed by health systems with limited resources. We undertook a study from September to December 2021 to compare the feasibility and coverage of VASD locally delivered by community health volunteers (CHV) ("intervention arm") to that achieved by the bi-annual Malezi Bora campaign event ("control arm"). This comparative cross-sectional study was conducted in sub-counties of Siaya County using both qualitative and quantitative methods. VASD were offered through the CHS in Alego Usonga and through Malezi Bora in Bondo Sub-County. Coverage was assessed by a post-event coverage survey among caregivers of children aged 6-59 months (n = 307 intervention; n = 318 control). Key informant interviews were conducted with n = 43 personnel across both modalities, and 10 focus group discussions were conducted with caregivers of children aged 6-59 months to explore knowledge, attitudes and perceptions of the two strategies. VAS coverage by CHV was 90.6% [95% CI: 87.3-93.9] compared to 70.4% [95% CI: 65.4-75.4] through the Malezi Bora, while deworming coverage was 73.9% [95% CI: 69.0-78.7] and 54.7% [95% CI: 49.2-60.2], respectively. With sufficient training and oversight, CHV can achieve superior coverage to campaigns.

Heavy episodic drinking and self-reported increased alcohol use during the COVID-19 pandemic: a spotlight on frontline and essential workers in Canada. / Forte consommation épisodique d'alcool et consommation autodéclarée accrue d'alcool pendant la pandémie de COVID-19 : un regard sur les travailleurs de première ligne et les travailleurs essentiels au Canada.

INTRODUCTION: There is evidence that some frontline and essential workers have increased their alcohol use during the COVID-19 pandemic; however, this has not been examined in Canada. METHODS: Using the Survey on COVID-19 and Mental Health 2020, weighted prevalence and 95% confidence intervals of self-reported increased alcohol consumption and heavy episodic drinking were calculated for each of the population groups: frontline workers, essential workers, and nonfrontline or essential workers (NFEW). Logistic regression was used to examine the associations between social determinants of health, mental health and alcohol use for each group. RESULTS: The prevalence of increased alcohol consumption and past-month heavy episodic drinking did not differ across frontline workers, essential workers and NFEW. For the three groups, nonracialized group members had significantly higher odds for both outcomes. Screening positive for either generalized anxiety disorder or mood disorder was significantly associated with increased alcohol consumption across the three groups. For frontline and essential workers, females had significantly lower odds of heavy episodic drinking compared to males. For essential workers only, living in a rural area was significantly associated with lower odds of increased alcohol use, and screening positive for posttraumatic stress disorder was significantly associated with increased odds of heavy episodic drinking. For frontline workers only, living in a rural area was significantly associated with lower odds of heavy episodic drinking. CONCLUSION: While frontline and essential workers were not more likely to report increased alcohol consumption and heavy episodic drinking compared to NFEW, there were some differences in factors associated with alcohol use. Such findings demonstrate the benefit of examining each group separately to provide information for targeted prevention strategies.

COVID-19 concerns among caregivers and vitamin A supplementation coverage among children aged 6-59 months in four countries in Western sub-Saharan Africa.

OBJECTIVE: To assess child vitamin A supplementation (VAS) coverage in 2019 and 2020 and explore key factors, including COVID-19 concerns, that influenced VAS status in four sub-Saharan African countries. DESIGN: Data from eight representative household surveys were used to assess VAS coverage. Multivariable logistic regression models examined the effect of rural/urban residence, child sex and age, caregiver education, COVID-19 concern and household wealth on VAS status. SETTING: Nine (2019) and 12 (2020) districts in Burkina Faso, Côte d'Ivoire, Guinea and Mali. PARTICIPANTS: 28 283 caregivers of children aged 6-59 months. RESULTS: Between 2019 and 2020, VAS coverage increased in Burkina Faso (82·2-93·1 %), Côte d'Ivoire (90·3-93·3 %) and Mali (76·1-79·3 %) and decreased in Guinea (86·0 % to 81·7 %). Rural children had a higher likelihood of VAS uptake compared with urban children in Burkina Faso (adjusted OR (aOR) = 4·22; 95 % CI: 3·11, 5·72), Côte d'Ivoire (aOR = 5·19; 95 % CI: 3·10, 8·70) and Mali (aOR = 1·41; 95 % CI: 1·15, 1·74). Children aged 12-59 months had a higher likelihood of VAS uptake compared with children aged 6-11 months in Côte d'Ivoire (aOR = 1·67; 95 % CI: 1·12, 2·48) and Mali (aOR = 1·74; 95 % CI: 1·34, 2·26). Moderate-to-high COVID-19 concern was associated with a lower likelihood of VAS uptake in Côte d'Ivoire (aOR = 0·55; 95 % CI: 0·37, 0·80). CONCLUSION: The increase in VAS coverage from 2019 to 2020 suggests that COVID-19 concerns may not have limited VAS uptake in some African countries, though geographic inequities should be considered.

Vaping-associated lung illness (VALI) in Canada: a descriptive analysis of VALI cases reported from September 2019 to December 2020. / La maladie pulmonaire associée au vapotage (MPAV) au Canada : une analyse descriptive des cas de MPAV signalés entre septembre 2019 et décembre 2020.

INTRODUCTION: The aim of this study was to explore demographic and clinical characteristics of vaping-associated lung illness (VALI) cases reported in Canada from September 2019 to December 2020; compare the epidemiology of VALI cases in Canada to e-cigarette or vaping product use-associated lung injury (EVALI) cases in the US; and examine possible explanations for differences between the two countries. METHODS: A federal/provincial/territorial task group developed a national outbreak definition, minimum dataset and case report form for identification and surveillance of VALI cases in Canada. Descriptive analysis explored the characteristics and epidemiology of reported VALI cases. RESULTS: Of the 20 VALI cases reported, none resulted in a death. Of all cases, 5 (25%) involved youth aged 15 to 19 years, 10 (50%) adults aged 20 to 49 years and 5 (25%) aged 50 years and older. Sixty percent of patients were men. Half (50%) required breathing assistance. Three-quarters (75%) reported using nicotine-containing vaping products, and 40% reported use of cannabis-containing vaping products; of those who reported frequency of vaping, most (71%) reported vaping daily. VALI cases were reported at a lower prevalence (0.9 per million) than EVALI (8.5 per million). Demographics and vaping behaviour also differed. CONCLUSION: VALI cases were reported in Canada between September 2019 and December 2020; however, there was a much lower prevalence and they may have been caused by different factors from the EVALI outbreak in the US. The factors influencing VALI in Canada are complex and multifactorial. Research is needed to understand the short- and long-term health effects of nicotine and cannabis vaping.

Measuring self-reported change in alcohol and cannabis consumption during the second wave of the COVID-19 pandemic in Canada. / Mesurer les changements autodéclarés relatifs à la consommation d'alcool et de cannabis au cours de la deuxième vague de la pandémie de COVID 19 au Canada.

This study presents nationally representative estimates of self-reported changes in alcohol and cannabis consumption since the onset of COVID-19 in Canada. We used data from the Survey on COVID-19 and Mental Health (collected from September to December 2020) to calculate the prevalence of self-reported change in alcohol and cannabis consumption. We found that 15.7% of respondents self-reported an increase in alcohol consumption and 5.4% in cannabis consumption since the start of the pandemic. Sociodemographic disparities were also observed, indicating that increased alcohol and cannabis consumption may be more prevalent among certain populations.

From 11 September to 4 December 2020, 15.7% and 5.4% of individuals self-reported an increase in alcohol and cannabis consumption, respectively, compared to before the pandemic. Individuals who reported that their mental health was worse now, compared to before the pandemic, had the highest prevalence of self-reported increase in alcohol and cannabis consumption. Understanding the social determinants of health is critical to the development of harm reduction and mitigation strategies.

Entre le 11 septembre et le 4 décembre 2020, 15,7 % des répondants ont déclaré avoir augmenté leur consommation d'alcool et 5,4 % leur consommation de cannabis par rapport à avant la pandémie. Les personnes ayant déclaré que leur santé mentale était pire au moment de l'Enquête qu'avant la pandémie offraient la prévalence la plus forte en matière d'augmentation de la consommation d'alcool et de cannabis. Il est primordial de comprendre les déterminants sociaux de la santé pour élaborer des stratégies de réduction des méfaits et d'atténuation.

Applying a gendered lens to understanding self-reported changes in alcohol and cannabis consumption during the second wave of the COVID-19 pandemic in Canada, September to December 2020. / Adopter une perspective axée sur le genre pour comprendre les changements autodéclarés dans la consommation d'alcool et de cannabis pendant la deuxième vague de la pandémie de COVID 19 au Canada, septembre à décembre 2020.

INTRODUCTION: Increased alcohol and cannabis consumption and related harms have been reported since the beginning of the COVID-19 pandemic. Existing evidence shows that substance use and related harms differ by gender. Yet, no Canadian study has applied a gendered lens to alcohol and cannabis consumption use during this time. Our objectives were to (1) provide gender-specific prevalence estimates of self-reported increased alcohol and cannabis use; and (2) examine gender-specific associations between sociodemographic and mental health variables and alcohol and cannabis use. METHODS: Using data from the Survey on COVID-19 and Mental Health, we calculated nationally representative, gender-specific prevalence estimates and disaggregated them by sociodemographic and mental health variables. Four logistic regression models were used to assess the likelihood of self-reported increased alcohol and cannabis use. RESULTS: The prevalence of self-reported increase in alcohol use (16.2% women; 15.2% men) and cannabis use (4.9% women; 5.8% men) did not differ by gender. For both genders, income, racialized group membership, working in the past week, being a parent/legal guardian of a child aged under 18 and screening positive for depression and anxiety were associated with increased alcohol use. Men and women who were between the ages of 18 to 44, screened positive for depression, or both, were more likely to report increased cannabis use. For women, education was significantly associated with increased alcohol use. For men, being a parent/legal guardian was significantly associated with lower odds of increased cannabis use. CONCLUSION: Sociodemographic factors, as well as depression and anxiety, were similarly associated with increased alcohol and cannabis use for both men and women in the second wave of the pandemic.

Prevalence of alcohol use among women of reproductive age in Canada. / Fréquence de la consommation d'alcool chez les Canadiennes en âge de procréer.

INTRODUCTION: Reporting on alcohol use among women of reproductive age in Canada addresses a major gap in evidence. METHODS: We assessed the prevalence of weekly and heavy alcohol consumption among women aged 15 to 54 years by sociodemographic characteristics, province of residence and concurrent use of other substance(s) using data from the 2019 Canadian Community Health Survey. RESULTS: Of the target population, 30.5% reported weekly and 18.3% reported heavy alcohol consumption in the past year. Prevalence varied by sociodemographic characteristics, province and substance use. The most notable and significant differences were to do with cannabis use and smoking. CONCLUSION: This information can guide health care providers in assessing alcohol consumption and in promoting low-risk alcohol drinking to prevent alcohol exposure during pregnancy.

Trends in Suicide Mortality in Canada by Sex and Age Group, 1981 to 2017: A Population-Based Time Series Analysis: Tendances de la mortalité par suicide au Canada selon le sexe et le groupe d'âge, 1981 - 2017 : Une analyse de séries chronologiques dans la population.

OBJECTIVES: Suicide is a complex global public health issue. The objective of this study was to assess time trends in suicide mortality in Canada by sex and age group. METHODS: We extracted data from the Canadian Vital Statistics Death Database for all suicide deaths among individuals aged 10 years and older based on International Statistical Classification of Diseases and Related Health Problems, Ninth Revision (E950-959; 1981 to 1999) and International Statistical Classification of Diseases and Related Health Problems, 10th Revision (X60-X84, Y87·0; 2000 to 2017) for a 37-year period, from 1981 to 2017. We calculated annual age-standardized, sex-specific, and age group-specific suicide mortality rates, and used Joinpoint Regression for time trend analysis. RESULTS: The age-standardized suicide mortality rate in Canada decreased by 24.0% from 1981 to 2017. From 1981 to 2007, there was a significant annual average decrease in the suicide rate by 1.1% (95% confidence interval, -1.3 to -0.9), followed by no significant change between 2007 and 2017. From 1981 to 2017 and from 1990 to 2017, females aged 10 to 24 and 45 to 64 years old, respectively, had a significant increase in suicide mortality rates. However, males had the highest suicide mortality rates in all years in the study; the average male-to-female ratio was 3.4:1. CONCLUSION: The 3-decade decline in suicide mortality rates in Canada paralleled the global trend in rate reductions. However, since 2008, the suicide rate in Canada was relatively unchanged. Although rates were consistently higher among males, we found significant rate increases among females in specific age groups. Suicide prevention efforts tailored for adult males and young and middle-aged females could help reduce the suicide mortality rate in Canada.

Opioid and Cannabis Use During Pregnancy and Breastfeeding in Relation to Sociodemographics and Mental Health Status: A Descriptive Study.

OBJECTIVE: This study of Canadian women estimates the prevalence of opioid and cannabis use during pregnancy and cannabis use during the breastfeeding period and explores the sociodemographic and mental health characteristics associated with use. METHODS: A total of 13 000 women who gave birth between January and June 2018 were invited to participate in the Survey on Maternal Health by Statistics Canada; 7111 women participated for a response rate of 54.7%. Participants were asked about their mental health, supports during pregnancy, and substance use. Multivariable logistic regression was used to describe the relationship between sociodemographic and mental health characteristics and substance use during pregnancy and while breastfeeding. RESULTS: The prevalence of self-reported opioid use during pregnancy was 1.4% (95% confidence interval [CI] 1.1%-1.8%). A higher proportion of women reported using cannabis during pregnancy and while breastfeeding, at 3.1% (95% CI 2.5%-3.6%) and 2.6% (95% CI 2.1%-3.1%), respectively. Younger age, not being in a relationship, lower level of education, and thoughts of self-harm were significantly associated with cannabis use during pregnancy. Lower level of education and thoughts of self-harm were also significantly associated with cannabis use while breastfeeding, as were symptoms of postpartum depression and/or generalized anxiety. Lower level of education and symptoms of postpartum depression and/or generalized anxiety were also significantly associated with opioid use during pregnancy. CONCLUSION: The results of this survey show relatively low levels of opioid and cannabis use during pregnancy and cannabis use while breastfeeding in Canada. Different sociodemographic and mental health characteristics are associated with the use of these substances, and public health interventions and policies should take into account these factors.

Measuring positive mental health and flourishing in Denmark: validation of the mental health continuum-short form (MHC-SF) and cross-cultural comparison across three countries.

BACKGROUND: The Mental Health Continuum-Short Form (MHC-SF) is a measure of positive mental health and flourishing, which is widely used in several countries but has not yet been validated in Denmark. This study aimed to examine its qualitative and quantitative properties in a Danish population sample and compare scores with Canada and the Netherlands. METHODS: Three thousand five hundred eight participants aged 16-95 filled out an electronic survey. Both the unidimensional and multidimensional aspects of the Danish MHC-SF were studied through bifactor modelling. Cognitive interviews examined face validity and usability. RESULTS: The general score of the Danish MHC-SF was reliable for computing unit-weighted composite scores, as well as using a bifactor model to compute general factor scores or measurement models in an SEM context. Nonetheless, subscale scores were unreliable, explaining very low variance beyond that explained by the general factor. The participants of the qualitative interviews observed problems with wording and content of the items, especially from the social subscale. The general score correlated with other scales as expected. We found substantial variation in flourishing prevalence rates between the three cultural settings. CONCLUSIONS: The Danish MHC-SF produced reliable general scores of well-being. Most of the issues observed regarding the subscale scores have been shown in previous research in other contexts. The further analysis of indices of the bifactor model and the inclusion of qualitative interviews allowed for a better understanding of the possible sources of problems with the questionnaire's subscales. The use of subscales, the substantive understanding of the general score, as well as the operationalization of the state of flourishing, require further study.

Thoughts of self-harm and associated risk factors among postpartum women in Canada.

BACKGROUND: The prevalence of thoughts of self-harm during the postpartum period is not well documented in Canada. To estimate the prevalence of thoughts of self-harm among postpartum women in Canada, this study explored prevalence by socio-demographic characteristics and examined the associations between thoughts of self-harm and aspects of maternal mental health. METHODS: This study used data from the 2018/2019 Survey on Maternal Health which surveyed women living in the 10 provinces anywhere between 6-13 months postpartum. Participants were asked to report experiencing thoughts of self-harm, rate their mental health, and participate in the abbreviated Edinburgh Postpartum Depression Scale and Generalized Anxiety Disorder (GAD) scale. Adjusted logistic regression analyses were performed to examine associations. RESULTS: Of the 6,558 respondents who agreed to share their data, 10.4% reported thoughts of self-harm since the birth of their child. Of these women, 37.0% reported low mental health, 54.2% had moderate levels of symptoms of postpartum depression (PPD) and 37.1% had symptoms of GAD. Women who experienced low mental health, moderate levels of symptoms of PPD and/or GAD were more likely to report thoughts of self-harm. LIMITATIONS: As thoughts of self-harm and aspects of mental health are self-reported, there is the potential for social desirability bias and underreporting. The cross-sectional survey design did not allow the reporting of thoughts of self-harm at different time points. DISCUSSION: The high proportion of postpartum women in Canada reporting thoughts of self-harm and strong associations with aspects of maternal mental health highlight the need for effective supports during postpartum.

Prevalence of Positive Mental Health and Associated Factors Among Postpartum Women in Canada: Findings from a National Cross-Sectional Survey.

OBJECTIVES: The objectives of this study were to compare the prevalence of three positive mental health (PMH) outcomes (self-rated mental health, life satisfaction, sense of community belonging) in postpartum women to the general population, and to examine the relationship between protective factors and the three PMH outcomes among postpartum women. METHODS: The national cross-sectional Survey on Maternal Health (n = 6558) was analyzed. Analyses were weighted and 95% confidence intervals were calculated. Three adjusted logistic regression models were generated. To compare this sample to the general population of women, estimates from the Canadian Community Health Survey-Annual Component (2018) were used. RESULTS: Compared to the general population of women, a larger proportion of postpartum women reported a strong sense of community belonging. The odds of postpartum women with high self-rated physical health having high self-rated mental health were approximately seven times greater (aOR 6.9, 95% confidence interval [CI] 5.9, 8.1) than postpartum women with lower self-rated physical health. The absence of symptoms of postpartum depression (PPD) or generalized anxiety disorder (GAD) and high self-rated physical health were significantly associated with all three PMH outcomes. Frequent availability of maternal support was associated with greater odds of high life satisfaction (aOR 1.6, 95% CI 1.4, 1.9) and sense of community belonging (aOR 1.4, 95% CI 1.2, 1.6). CONCLUSIONS: Our study demonstrated that availability of maternal support, self-rated physical health and absence of symptoms of PPD or GAD were associated with PMH among postpartum women. As physical health had the strongest association with mental health, we encourage further examination of this relationship.

Examining Play Counts and Measurements of Injury Incidence in Youth Football.

CONTEXT: Whereas researchers have provided estimates for the number of head impacts sustained within a youth football season, less is known about the number of plays across which such impact exposure occurs. OBJECTIVE: To estimate the number of plays in which youth football players participated during the 2013 season and to estimate injury incidence through play-based injury rates. DESIGN: Descriptive epidemiology study. SETTING: Youth football. PATIENTS OR OTHER PARTICIPANTS: Youth football players (N = 2098; age range, 5-15 years) from 105 teams in 12 recreational leagues across 6 states. MAIN OUTCOME MEASURE(S): We calculated the average number of athlete-plays per season and per game using independent-samples t tests to compare age groups (5-10 years old versus 11-15 years old) and squad sizes (<20 versus ≥20 players); game injury rates per 1000 athlete-exposures (AEs) and per 10 000 athlete-plays; and injury rate ratios (IRRs) with 95% confidence intervals (CIs) to compare age groups. RESULTS: On average, youth football players participated in 333.9 ± 178.5 plays per season and 43.9 ± 24.0 plays per game. Age groups (5- to 10-year-olds versus 11- to 15-year-olds) did not differ in the average number of plays per season (335.8 versus 332.3, respectively; t2086.4 = 0.45, P = .65) or per game (44.1 versus 43.7, respectively; t2092.3 = 0.38, P = .71). However, players from smaller teams participated in more plays per season (373.7 versus 308.0; t1611.4 = 8.15, P < .001) and per game (47.7 versus 41.4; t1523.5 = 5.67, P < .001). Older players had a greater game injury rate than younger players when injury rates were calculated per 1000 AEs (23.03 versus 17.86/1000 AEs; IRR = 1.29; 95% CI = 1.04, 1.60) or per 10 000 athlete-plays (5.30 versus 4.18/10 000 athlete-plays; IRR = 1.27; 95% CI = 1.02, 1.57). CONCLUSIONS: A larger squad size was associated with a lower average number of plays per season and per game. Increasing youth football squad sizes may help reduce head-impact exposure for individual players. The AE-based injury rates yielded effect estimates similar to those of play-based injury rates.

Epidemiology of Sport-Related Concussions in High School Athletes: National Athletic Treatment, Injury and Outcomes Network (NATION), 2011-2012 Through 2013-2014.

CONTEXT: Sports participation is one of the leading causes of concussions among nearly 8 million US high school student-athletes. OBJECTIVE: To describe the epidemiology of sport-related concussion (SRC) in 27 high school sports during the 2011-2012 through 2013-2014 academic years. DESIGN: Descriptive epidemiology study. SETTING: Aggregate injury and exposure data from 27 sports in 147 high schools in the National Athletic Treatment, Injury and Outcomes Network (NATION). PATIENTS OR OTHER PARTICIPANTS: Boy and girl high school athletes during the 2011-2012 through 2013-2014 academic years. MAIN OUTCOME MEASURE(S): Sport-related concussion counts, percentages, rates per 10 000 athlete-exposures (AEs), rate ratios (RRs), and injury proportion ratios (IPRs) were reported with 95% confidence intervals (CIs). Rate ratios and IPRs with 95% CIs not containing 1.0 were considered significant. RESULTS: Overall, 2004 SRCs were reported among 27 high school sports, for a rate of 3.89 per 10 000 AEs. Football had the highest SRC rate (9.21/10 000 AEs), followed by boys' lacrosse (6.65/10 000 AEs) and girls' soccer (6.11/10 000 AEs). The SRC rate was higher in competition than in practice (RR = 3.30; 95% CI = 3.02, 3.60). Among sex-comparable sports, the SRC rate was higher in girls than in boys (RR = 1.56; 95% CI = 1.34, 1.81); however, the proportion of SRCs due to player-to-player contact was higher in boys than in girls (IPR = 1.48; 95% CI = 1.27, 1.73). Common symptoms reported among all athletes with SRCs were headache (94.7%), dizziness (74.8%), and difficulty concentrating (61.0%). Only 0.8% of players with SRCs returned to play within 24 hours. The majority of athletes with SRCs (65.8%) returned to play between 7 and 28 days. More players had symptoms resolve after 7 days (48.8%) than less than a week (40.7%). CONCLUSIONS: Our findings provide updated high school SRC incidence estimates and further evidence of sex differences in reported SRCs. Few athletes with SRCs returned to play within 24 hours or a week. Most injured players returned after 7 days, despite a smaller proportion having symptoms resolve within a week.