Sexual orientation and adolescent suicide attempt and self-harm: a co-twin control study.

BACKGROUND: Research has demonstrated that individuals who identify as a sexual minority (e.g., gay/lesbian, bisexual) are at increased risk for suicidality-related outcomes. However, previous research is primarily limited by the lack of adjustment for unmeasured (i.e., genetic and environmental) confounding factors and previous psychopathology. METHODS: Using the Child and Adolescent Twin Study in Sweden, we employed a co-twin control design to examine the extent to which the association between sexual orientation and adolescent suicide attempt and self-harm (SA/SH) was independent of genetic and environmental factors shared by twins, as well as measured symptoms of childhood psychopathology. RESULTS: Adolescents who identified as a sexual minority (i.e., gay/lesbian, bisexual, or other sexual orientation) were at two-fold increased odds for SA/SH (OR, 2.01 [95% confidence interval, 1.63-2.49) compared to heterosexual adolescents. When adjusting for all genetic and shared environmental factors that make twins similar and for measured childhood psychopathology, the association remained positive but attenuated to OR, 1.55 (1.11-2.16). CONCLUSIONS: Identifying as a sexual minority was associated with approximately 50% increased odds of SA/SH in adolescence after adjusting for unmeasured genetic and environmental factors shared by twins and for childhood psychopathology. The results support that environmental factors specifically associated with identifying as a sexual minority likely increase risk for SA/SH. Our findings highlight the need to monitor suicidality risk among this group.

The association between maternal human papillomavirus (HPV) experiences and HPV vaccination of their children.

HPV vaccination prevents most HPV-related cancers yet vaccination rates remain low. In this cross-sectional study, we examined the association between maternal HPV experiences and HPV vaccination uptake among children and whether this association may be explained by perceived benefits of vaccination. We used logistic regression models to estimate the effect of (1) maternal history of abnormal Pap smear, (2), family/friend history of cervical cancer, and (3) maternal history of cervical cancer on HPV vaccination uptake among children. Separate mediation analyses were conducted to determine if perceived benefits mediated the relationship between each maternal HPV experience and HPV vaccination uptake. History of abnormal Pap smear (OR = 1.50, 95% CI = 1.15, 1.97), family history of cervical cancer (OR = 1.72, CI = 1.26, 2.35), and personal history of cervical cancer (OR = 3.00, CI = 1.82, 4.95) predicted HPV vaccination of children. Perceived benefits mediated the relationship between history of abnormal Pap smear (indirect effect =.146, SE =.069, 95% CI =.014, .289), family history of cervical cancer (indirect effect =.228, SE =.079, CI =.080, .387), and personal history of cervical cancer (indirect effect =.298, SE =.116, CI =.082, .533) on HPV vaccination. Our results suggest that personal experiences with HPV-related disease may influence maternal HPV vaccine decision-making.

Nontraditional School Enrollment in Transgender and Gender-Diverse Youth.

PURPOSE: This study aimed to investigate the prevalence of online and homeschool attendance in transgender and gender-diverse (TGD) youth. METHODS: Caregivers of 12- to 17-year-olds participated in a phone survey about school attendance. Subjects included TGD youth receiving care in a gender health clinic and youth receiving care in a pediatric endocrinology/diabetes (PED) clinic. RESULTS: Parents of 83 TGD and 83 PED youth participated in the study. Current/past enrollment in a nontraditional school setting was higher among TGD than PED youth (37.3% vs. 19.3%; p = .01). In addition, 14.5% of TGD and 7.2% of PED youth had transferred between traditional school settings (public, private, and charter) for psychosocial reasons. CONCLUSIONS: Approximately half of the TGD youth had either attended a nontraditional school setting or changed schools for psychosocial reasons, compared with approximately one fourth of PED youth (51.8% vs. 26.5%, p = .001). This suggests that traditional school environments present significant psychological difficulties for TGD adolescents.

The association between nutrition and behavioural health in a US Army population.

OBJECTIVE: The relationship between nutrition and behavioural health (BH) outcomes has been established in the literature. However, the relationship between nutrition and anxiety is unclear. Furthermore, the relationship between nutrition and BH outcomes has not been examined in a US Army Soldier population. This study sought to understand the relationship between Soldiers' nutritional intake and anxiety as well as depression. DESIGN: This cross-sectional study utilised multivariable logistic regression analyses to examine the relationship between nutritional intake and BH outcomes. SETTING: The study utilised data collected in 2018 during a BH epidemiological consultation conducted at one Army installation. PARTICIPANTS: Participants were 7043 US Army Soldiers at one Army installation. RESULTS: Of the Soldiers completing the survey, 12 % (n 812) screened positive for anxiety and 11 % (n 774) for depression. The adjusted odds of anxiety were significantly higher among Soldiers who reported low fruit intake compared with Soldiers who reported high fruit intake (adjusted OR (AOR) 1·36; 95 % CI 1·04, 1·79). The adjusted odds of depression were higher for Soldiers who reported low fruit intake (AOR 1·35; 95 % CI 1·01, 1·79) and/or low green vegetable intake (AOR 1·37; 95 % CI 1·02, 1·83). Lastly, the adjusted odds of depression were lower for Soldiers who reported low sugary drink intake (AOR 0·62; 95 % CI 0·48, 0·81). CONCLUSIONS: This study is the first to examine the important connection between nutritional intake and anxiety and depression at a US military installation. The information learned from this study has implications for enhancing Soldiers' nutritional knowledge and BH, ultimately improving Soldiers' health and medical readiness.

Microbial-Based Double-Stranded RNA Production to Develop Cost-Effective RNA Interference Application for Insect Pest Management.

RNA interference (RNAi) is a convenient tool to identify and characterize biological functions in organisms. Recently, it has become an alternative to chemical insecticides as a biologically based control agent. This promising technology has the potential to avoid many problems associated with conventional chemical insecticides. In order for RNAi application to be practical for field use, a major hurdle is the development of a cost-effective system of double-stranded RNA (dsRNA) production for a large quantity of dsRNA. A handful of research reports has demonstrated microbial-based dsRNA production using L4440 vector and HT115 (DE3) Escherichia coli for application to vertebrate and invertebrate systems. However, the dsRNA yield, production efficiency, and biological purity from this in vitro system is still unclear. Thus, our study detailed biochemical and molecular tools for large-scale dsRNA production using the microbial system and investigated the production efficiency and yield of crude and purified dsRNAs. An unrelated insect gene, green fluorescent protein (GFP), and an insect neuropeptide gene, pyrokinin (PK) identified from Drosophila suzukii, were used to construct the recombinant L4440 to be expressed in the HT115 (DE3) cell. A considerable amount of dsRNA, 19.5 µg/mL of liquid culture, was isolated using ultrasonic disruption followed by phenol extraction. The sonication method was further evaluated to extract crude dsRNA without the additional phenol extraction and nuclease treatments and also to reduce potential bacterial viability. The results suggest that the ultrasonic method saved time and costs to isolate crude dsRNA directly from large volumes of cell culture without E coli contamination. We investigated whether the injection of PK dsRNA into flies resulted in increased adult mortality, but it was not statistically significant at 95% confidence level. In this study, the microbial-based dsRNA production has potential for applied RNAi technology to complement current insect pest management practices.

Characteristics of Usual Physical Therapy Post-Total Knee Replacement and Their Associations With Functional Outcomes.

OBJECTIVE: Although total knee replacement (TKR) surgery is highly prevalent and generally successful, functional outcomes post-TKR vary widely. Most patients receive some physical therapy (PT) following TKR, but PT practice is variable and associations between specific content and dose of PT interventions and functional outcomes are unknown. Research has identified exercise interventions associated with better outcomes but studies have not assessed whether such evidence has been translated into clinical practice. We characterized the content, dose, and progression of usual post-acute PT services following TKR, and examined associations of specific details of post-acute PT with patients' 6-month functional outcomes. METHODS: Post-acute PT data were collected from patients who were undergoing primary unilateral TKR and participating in a clinical trial of a phone-based coaching intervention. PT records from the terminal episode of care were reviewed and utilization and exercise content data were extracted. Descriptive statistics and linear regression models characterized PT treatment factors and identified associations with 6-month outcomes. RESULTS: We analyzed 112 records from 30 PT sites. Content and dose of specific exercises and incidence of progression varied widely. Open chain exercises were utilized more frequently than closed chain (median 21 [interquartile range (IQR) 4-49] versus median 13 [IQR 4-28.5]). Median (IQR) occurrence of progression of closed and open chain exercise was 0 (0-2) and 1 (0-3), respectively. Shorter timed stair climb was associated with greater total number of PT interventions and use and progression of closed chain exercises. DISCUSSION: Data suggest that evidence-based interventions are underutilized and dose may be insufficient to obtain optimal outcomes.

Provider Communication and Mothers' Willingness to Vaccinate Against Human Papillomavirus and Influenza: A Randomized Health Messaging Trial.

OBJECTIVE: To understand the effect of a health messaging intervention focused on provider communication about vaccination on mothers' willingness to vaccinate children against human papillomavirus (HPV) and seasonal influenza. METHODS: A total of 2476 mothers of 9- to 13-year-olds in the United States completed a Web-based survey in August 2014. Mothers were randomized to 1 of 2 groups targeting HPV or influenza vaccine. Mothers whose child had not received the target vaccine (ie, zero doses of HPV vaccine/no prior-year administration of influenza vaccine) were randomized to the intervention. The study used a 3 × 2 between-subjects design; illustrated vignettes depicted 1 of 3 levels of provider recommendation strength (brief mention of vaccination, strong recommendation of vaccination, or personal disclosure of vaccination of own children), and presence or absence of information comparing safety of vaccination to the safety of a common daily activity. Outcome was mothers' willingness to have their child receive the target vaccine. Perceived benefits of vaccination were assessed before viewing the intervention and were included as a covariate in analyses, along with child gender. RESULTS: For HPV vaccine, there was a main effect of safety information (F(1,684) = 7.99, P = .005) and perceived benefits of vaccination (F(1,684) = 221.64, P < .001) on mothers' willingness to vaccinate. For influenza, perceived benefits of vaccination significantly related to willingness to vaccinate (F(1,462) = 105.78, P < .001). Child gender was not associated with willingness. CONCLUSIONS: Provider communication about vaccination may need to be tailored to the vaccine in question. A next step to increasing coverage for both HPV and influenza vaccines may be an intervention aimed at increasing mothers' perceived benefits of vaccination.

One-Year Follow-Up of Girls with Precocious Puberty and Their Mothers: Do Psychological Assessments Change over Time or with Treatment?

BACKGROUND: To determine whether psychological characteristics of girls with variations of early puberty and their mothers change over time and with treatment in girls with central precocious puberty (CPP). METHODS: Girls with CPP, premature adrenarche (PA), and early normal puberty (ENP) completed psychological assessments at baseline and after 1 year along with their mothers. All girls with CPP were treated with GnRH analogs. Psychological effects of group and time were examined using 2 × 3 mixed ANOVAs. RESULTS: Sixty-two subjects aged 7.5 ± 1.4 years (range 4.8-10.5) were enrolled, of whom 36 (15 with CPP, 8 with PA, and 13 with ENP) completed 1-year follow-up assessments. Psychological measures were normal in all girls. No significant group differences were found for any measure of girls' psychological functioning at either time point. However, across all groups there was change over time with a decrease in perceived physical competence (p < 0.001) and an increase in perceived maternal acceptance (p = 0.001). CONCLUSION: No abnormalities in psychological functioning were found among girls with variations of early puberty, and all groups were in the normal range. Our results are largely reassuring regarding concerns of adverse psychological consequences of early puberty in girls.

Pediatrician-Parent Conversations About Human Papillomavirus Vaccination: An Analysis of Audio Recordings.

PURPOSE: We sought to establish which human papillomavirus (HPV) vaccine communication approaches by pediatricians were associated with same-day HPV vaccination of 11- to 12-year-olds by evaluating audio recordings of visits. METHODS: Verilogue, a market research company maintaining a panel of primary care pediatricians, provided audio recordings and transcriptions of well-child visits for 11- to 12-year-old patients from January through June 2013. Seventy-five transcripts from 19 pediatricians were coded for use of presumptive language (i.e., words conveying assumption of vaccine delivery), offer of delay, recommendation strength, and information provision. Using logistic regression, we evaluated the association between pediatrician communication approaches and agreement to same-day HPV vaccination. Generalized estimating equations accounted for clustering of patients within pediatricians. RESULTS: Same-day agreement to HPV vaccination occurred in 29% of encounters. Pediatricians in the sample often provided parents with inconsistent, mixed messages and sometimes offered information about HPV or HPV vaccination that was inaccurate. Pediatricians used presumptive language in only 11 of 75 encounters; when used, presumptive language was associated with higher odds of accepting HPV vaccine (73% vs. 22%; odds ratio = 8.96; 95% confidence interval = 2.32-34.70). Pediatricians offered or recommended delay in most encounters (65%). HPV vaccine acceptance occurred far more often when pediatricians did not mention delaying vaccination (82% vs. 6%; odds ratio = 80.84; 95% confidence interval = 15.72-415.67). Same-day vaccination was not associated with strength of recommendation or pediatrician reference to vaccinating their own children. CONCLUSIONS: Our findings highlight the need to develop and evaluate physician-focused trainings on using presumptive language for same-day HPV vaccination.

Predictors of influenza vaccination in the U.S. among children 9-13years of age.

BACKGROUND AND OBJECTIVES: U.S. estimates of seasonal influenza (flu) vaccine uptake in 2014-2015 were 62% for 5-12year olds, dropping to 47% for 13-17year olds. The Healthy People 2020 goal for these age groups is 80%. It is important to understand factors associated with influenza vaccination, especially for those ages where rates begin to decline. The objective of this study was to identify factors associated with influenza vaccination acceptance in 9-13year old children. METHODS: An online U.S. survey of mothers of children aged 9-13 assessed children's influenza vaccine uptake in the previous season, healthcare utilization, sociodemographics, and vaccine attitudes. Multivariable logistic regression identified independent predictors of influenza vaccine status. RESULTS: There were 2363 respondents (Mean age=38years old). Referent children were 57% female and 66% non-minority race/ethnicity with a mean age of 10.6years. By maternal report, 59% of children had received an influenza vaccine in the previous season. Predictors of influenza vaccine uptake included a recommendation or strong recommendation from a health care provider, seeing a health care provider in the past year, positive attitudes regarding the influenza vaccine, and being a minority race. Child gender, age, insurance coverage, and whether the child had a regular healthcare provider were not associated with influenza vaccine uptake (p=n.s.). CONCLUSIONS: This sample reported overall rates of influenza vaccine uptake similar to national surveillance data, but still lower than national goals. Provider recommendations along with health attitudes and seeing a health care provider were associated with vaccine uptake. Promising interventions may include more directive physician messaging for influenza vaccine uptake in youth, encouraging more regular well-child visits during the adolescent years, and promoting influenza vaccination at alternative sites.

Familial Factors, Victimization, and Psychological Health Among Sexual Minority Adolescents in Sweden.

OBJECTIVES: To determine the influences of victimization experience and familial factors on the association between sexual minority status and psychological health outcomes among adolescents. METHODS: We used data from the Child and Adolescent Twin Study in Sweden, a prospective, population-based study of all twins born in Sweden since 1992. Cross-sectional analyses included individuals who completed assessments at age 18 years (n = 4898) from 2000 to 2013. We also compared psychological health among sexual minority adolescents and their nonminority co-twins. RESULTS: Sexual minority adolescents were more likely than were unrelated nonminority adolescents to report victimization experiences, including emotional abuse, physical abuse or neglect, and sexual abuse. Sexual minority adolescents also reported significantly more symptoms of anxiety, depression, attention-deficit/hyperactivity disorder, disordered eating, and substance misuse in addition to increased parent-reported behavior problems. Victimization experience partially mediated these associations. However, when controlling for unmeasured familial confounding factors by comparing sexual minority adolescents to their same-sex, nonminority co-twins, the effect of sexual minority status on psychological health was almost entirely attenuated. CONCLUSIONS: Familial factors-common genetic or environmental influences-may explain decreased psychological adjustment among sexual minority adolescents.

Genetic and Environmental Contributions to Associations between Infant Fussy Temperament and Antisocial Behavior in Childhood and Adolescence.

Previous research suggests that fussy temperament in infancy predicts risk for later antisocial behavior (ASB) in childhood and adolescence. It remains unclear, however, to what extent infant fussiness is related to later ASB through causal processes or if they both reflect the same family risk factors for ASB. The current study used two approaches, the comparison of siblings and bivariate biometric modeling, to reduce familial confounding and examine genetic and environmental influences on associations between fussiness in the first 2 years of life and ASB in childhood and late adolescence. Analyses were conducted on data from a prospective cohort (9237 at 4-9 years and 7034 at 14-17 years) who are the offspring of a nationally representative sample of US women. In the full sample, fussiness predicted both child and adolescent ASB to small but significant extents, controlling for a wide range of measured child and family-level covariates. When siblings who differed in their fussiness were compared, fussiness predicted ASB in childhood, but not ASB during adolescence. Furthermore, results from a bivariate Cholesky model suggested that even the association of fussiness with childhood ASB found when comparing siblings is attributable to familial factors. That is, although families with infants who are higher in fussiness also tend to have children and adolescents who engage in greater ASB, the hypothesis that infant fussiness has an environmentally mediated impact on the development of future ASB was not strongly supported.

The Biochemical Adaptations of Spotted Wing Drosophila (Diptera: Drosophilidae) to Fresh Fruits Reduced Fructose Concentrations and Glutathione-S Transferase Activities.

Spotted wing drosophila, Drosophila suzukii Matsumura, is an invasive and economically damaging pest in Europe and North America. The females have a serrated ovipositor that enables them to infest almost all ripening small fruits. To understand the physiological and metabolic basis of spotted wing drosophila food preferences for healthy ripening fruits, we investigated the biological and biochemical characteristics of spotted wing drosophila and compared them with those of Drosophila melanogaster Meigen. We found that the susceptibility to oxidative stressors was significantly increased in spotted wing drosophila compared with those of D. melanogaster. In addition, we found that spotted wing drosophila had significantly reduced glutathione-S transferase (GST) activity and gene numbers. Furthermore, fructose concentrations found in spotted wing drosophila were significantly lower than those of D. melanogaster. Our data strongly suggest that the altered food preferences of spotted wing drosophila may stem from evolutionary adaptations to fresh foods accompanied by alterations in carbohydrate metabolism and GST activities.

Human Papillomavirus Vaccine Initiation among 9-13-Year-Olds in the United States.

OBJECTIVE: The quadrivalent and 9-valent human papillomavirus (HPV) vaccines are licensed for administration among 9-26-year-old males and females, with routine vaccination recommended for 11-12-year-olds. Despite the availability of the vaccine at younger ages, few studies have explored vaccine uptake prior to age 13, and national HPV vaccination surveillance data is limited to 13-17-year-olds. Our objective was to examine rates and predictors of HPV vaccine initiation among 9-13-year-olds in the United States. METHODS: A national sample of mothers of 9-13-year-olds in the United States (N=2,446) completed a 2014 Web-based survey assessing socio-demographic characteristics, child's HPV vaccination history, provider communication regarding the vaccine, and other attitudes and behaviors pertaining to vaccination and healthcare utilization. The main outcome measure was child's initiation of the HPV vaccine (i.e., receipt of one or more doses). RESULTS: Approximately 35% of the full sample and 27.5% of the 9-10-year-olds had initiated HPV vaccination. Females were more likely than males to have initiated HPV vaccination by the age of 13 but not by younger ages. Strength of health provider recommendation regarding HPV vaccination was a particularly salient predictor of vaccine initiation. CONCLUSIONS: Approximately a third of children may be initiating the HPV vaccine series before or during the targeted age range for routine administration of the vaccine. Because coverage remains below national targets, further research aimed at increasing vaccination during early adolescence is needed. Improving providers' communication with parents about the HPV vaccine may be one potential mechanism for increasing vaccine coverage.

Psychological assessment of mothers and their daughters at the time of diagnosis of precocious puberty.

BACKGROUND: Concerns about psychological distress are often used to justify treatment of girls with precocious puberty, but there is little evidence to support these concerns. The extent to which psychological problems are associated with central precocious puberty (CPP) compared with other forms of early puberty in girls has likewise not been established. METHODS: Girls presenting with untreated CPP, premature adrenarche (PA) or early normal puberty (ENP) were recruited from our pediatric endocrine clinic along with their mothers. Child psychological adjustment was assessed by child self-report and parent report. Parent self-reported personality, anxiety, and depression were also assessed. Differences between groups were explored using one-way ANOVA and Dunnett's T3 test. RESULTS: Sixty-two subjects (aged 7.5 ± 1.4 years, range 4.8-10.5) were enrolled, of whom 19 had CPP, 22 had PA, and 21 had ENP. Girls with ENP were significantly older (8.9 ± .9 years) than girls with CPP (6.9 ± 1.1 years, p < .001) and PA (6.6 ± 1.0 years, p < .001). Girls with PA had significantly higher BMI z-scores (1.7 ± .8) than girls with CPP (1.1 ± .6, p = .01) and ENP (1.2 ± .6, p = .04). More girls with PA and ENP were from racial minorities (47% and 50% respectively) than girls with CPP (32%). No group differences were found for any child measure of psychological adjustment. However, mothers of girls with PA scored significantly higher than mothers of girls with ENP on one measure of depression (p = .04) and stress (p = .01). CONCLUSIONS: While mothers of girls with PA report increased psychological distress on some measures, no differences in psychological adjustment were found at baseline amongst the girls themselves. Whether these results will change as puberty progresses in the PA and ENP groups or with treatment of CPP is unknown. Long-term prospective studies are needed in order to further investigate psychological correlates of early puberty in girls.

Individual and Partner Correlates of Sexual Satisfaction and Relationship Happiness in Midlife Couples: Dyadic Analysis of the International Survey of Relationships.

The current research reports a dyadic analysis of sexual satisfaction, relationship happiness, and correlates of these couple outcomes in a large multinational dataset consisting of 1,009 midlife heterosexual couples (2,018 individuals) recruited in Japan, Brazil, Germany, Spain, and the United States (Heiman et al., 2011). Actor-Partner Interdependence Models (Kenny, Kashy, & Cook, 2006) identified correlates of sexual satisfaction that included individuals' reports of good health; frequent kissing, cuddling, and caressing; frequent recent sexual activity; attaching importance to one's own and one's partner's orgasm; better sexual functioning; and greater relationship happiness. Even after controlling for individual-level effects, partners' reports of good health; frequent kissing, cuddling, and caressing; frequent recent sexual activity; attaching importance to one's own and one's partner's orgasm; better sexual functioning; and greater relationship happiness contributed significantly to predicting and understanding individuals' sexual satisfaction. Correlates of relationship happiness included individuals' reports of good health; frequent kissing, cuddling, and caressing; frequent recent sexual activity; attaching importance to one's own and one's partner's orgasm; better sexual functioning; and greater sexual satisfaction, and once again, even after controlling for individual-level effects, partners' reports of each of these correlates contributed significantly to predicting and understanding individuals' relationship happiness. Interactions of individual and partner effects with participant gender are also reported. Current results demonstrate empirically that the partner "matters" to an individual's sexual satisfaction and relationship happiness and indicate that a comprehensive understanding of factors contributing to these couple outcomes requires a couple-level research strategy. Partner effects, even when controlling for individual effects, were consistently observed, and explanation of sexual satisfaction and relationship happiness always depended on identifying and understanding mutual and concurrent individual and partner influences.

Vaccinating sons against HPV: results from a U.S. national survey of parents.

PURPOSE: The quadrivalent HPV vaccination was approved for use in males ages 9 to 26 in 2009 and recommended for routine administration in 2011. The purpose of this study was to uncover predictable commonalities amongst parents who chose to vaccinate their 11-17 year old sons against HPV. METHODS: We compiled data from a U.S. national sample of 779 parents with sons 11-17 years old using a web-based survey to gather information about behavioral and sociodemographic factors which predicted receipt of 1 or more HPV vaccine doses based on parental report. Predictors were first modeled individually for univariable associations. Significant predictors (p<0.10) were combined in a multivariable model. RESULTS: In the adjusted model, independent predictors included receipt of flu vaccination, health insurance coverage and sexual health topic discussions with sons. Sons who had received a flu shot in the last two years more frequently received at least one dose of the vaccine (OR 1.82; 95% CI 1.45-2.26). Sons covered by private health insurance had decreased odds of HPV vaccination (OR 0.56 95% CI 0.37-0.83). Lastly, parents who had discussed sexual health topics with their sons were more likely to vaccinate (OR 1.61; 95% CI 1.37-1.89). CONCLUSIONS: Male vaccination rates in the U.S. have increased, but males continue to be under-immunized. Utilization of health care is an important factor in HPV vaccine uptake; therefore, health care providers should use every contact as an opportunity to vaccinate. Communication about sexual health topics may provide a forum for parents and health care providers to have conversations about HPV vaccination as those more comfortable discussing these topics may also be more comfortable discussing HPV vaccination.

Acceptability of the human papillomavirus vaccine and reasons for non-vaccination among parents of adolescent sons.

Routine administration of the quadrivalent human papillomavirus (HPV) vaccine has been recommended for 11-12-year-old males since 2011, but coverage remains low. In a U.S. national sample of parents of 11-17-year-old males (n=779), 78.6% of parents reported their sons had not received the HPV vaccine. The most common reason for non-vaccination (56.7%) was "My doctor or healthcare provider has not recommended it." Parents citing only logistical reasons for non-vaccination (e.g., lack of recommendation, access, or education, n=384) reported significantly higher vaccine acceptability than parents reporting a combination of attitudinal (e.g., concerns about vaccine safety or efficacy) and logistical barriers (n=92), while parents citing only attitudinal barriers (n=73) reported the lowest level of vaccine acceptability. In sum, many parents are willing but have not vaccinated sons due to logistical barriers, most commonly lack of healthcare provider recommendation. These findings have important implications for increasing HPV vaccination coverage among adolescent males.