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EEG experiments yield high-dimensional event-related potential (ERP) data in response to repeatedly presented stimuli throughout the experiment. Changes in the high-dimensional ERP signal throughout the duration of an experiment (longitudinally) is the main quantity of interest in learning paradigms, where they represent the learning dynamics. Typical analysis, which can be performed in the time or the frequency domain, average the ERP waveform across all trials, leading to the loss of the potentially valuable longitudinal information in the data. Longitudinal time-frequency transformation of ERP (LTFT-ERP) is proposed to retain information from both the time and frequency domains, offering distinct but complementary information on the underlying cognitive processes evoked, while still retaining the longitudinal dynamics in the ERP waveforms. LTFT-ERP begins by time-frequency transformations of the ERP data, collected across subjects, electrodes, conditions and trials throughout the duration of the experiment, followed by a data driven multidimensional principal components analysis (PCA) approach for dimension reduction. Following projection of the data onto leading directions of variation in the time and frequency domains, longitudinal learning dynamics are modeled within a mixed effects modeling framework. Applications to a learning paradigm in autism depict distinct learning patterns throughout the experiment among children diagnosed with Autism Spectrum Disorder and their typically developing peers. LTFT-ERP time-frequency joint transformations are shown to bring an additional level of specificity to interpretations of the longitudinal learning patterns related to underlying cognitive processes, which is lacking in single domain analysis (in the time or the frequency domain only). Simulation studies show the efficacy of the proposed methodology.

BackgroundHuman papillomavirus (HPV) is epidemic among young people, especially those at highest risk of acquiring HPV-related cancers.MethodsYouth aged 14-24 years old (N = 1628) were recruited from 13 clinics, community agencies, and social media sites in Los Angeles, California, and New Orleans, Louisiana, that specialized in serving sexual and gender minority youths (SGMY), especially males at risk for HIV. A cross-sectional comparison of sociodemographic and risk histories of HPV vaccinated/unvaccinated youths was conducted using both univariate and multivariate regressions.ResultsAbout half (51.9%) of youth were vaccinated, with similar percentages across states and across genders. Sexual and gender minority youths (SGMY, i.e., gay, bisexual, transgender, and non-heterosexual; 68.8%) and their heterosexual peers (15%) were equally likely to be vaccinated (54%), even though their risk for HPV-related cancers is very different. Vaccinations were higher among younger youth, those not using condoms, youth with greater education, that possessed a primary health care provider, and youth diagnosed with HIV. Vaccinations were lower among youth that were out-of-home due to mental health inpatient hospitalization, drug treatment, homelessness, or incarceration.ConclusionsSpecial programs are required to target youth experiencing multiple life stressors, especially out-of-home experiences, those with less education, and without the safety net of health insurance or a provider.

BackgroundPublic health organizations have inconsistent recommendations for screening adolescents and young adults for Chlamydia trachomatis and Neisseria gonorrhoeae infections. Guidelines suggest different combinations of anorectal, pharyngeal, and urogenital testing based on age, sex, and sexual activity. Further evaluation of how identity and behaviors impact the anatomic distribution of C. trachomatis and N. gonorrhoeae infection is needed to optimize future screening practices.MethodsWe assessed the positivity of C. trachomatis and N. gonorrhoeae infections at different anatomic sites in a cohort of at-risk sexually active adolescents and young adults aged 12-24 years in New Orleans, Louisiana and Los Angeles, California. Participants were tested for C. trachomatis and N. gonorrhoeae at 3 sites (anorectum, pharynx, and urethral/cervix) every 4 months using self-collected swabs. We stratified anatomic distributions of infection into 4 gender and sexual behavior categories: (1) cisgender men who have sex with men and transgender women (MSMTW); (2) cisgender heterosexual males; (3) cisgender heterosexual females; and (4) gender minorities assigned female at birth.ResultsWhile three-site testing detected all infections, two-site (anorectum and urethra/cervix) testing identified 92%-100% of C. trachomatis or N. gonorrhoeae infections in participants assigned female at birth and cisgender heterosexual males. For MSMTW, two-site anorectal and pharyngeal testing vs single-site anorectal testing increased the proportion of individuals with either infection from 74% to 93%.ConclusionsSexual behavior and gender identity may influence detection of C. trachomatis and N. gonorrhoeae infections at specific anatomic testing sites. Testing guidelines should incorporate sexual behavior and gender identity.Clinical trials registrationNCT03134833.

Machine learning creates new opportunities to design digital health interventions for youth at risk for acquiring HIV (YARH), capitalizing on YARH's health information seeking on the internet. To date, researchers have focused on descriptive analyses that associate individual factors with health-seeking behaviors, without estimating of the strength of these predictive models. We developed predictive models by applying machine learning methods (i.e., elastic net and lasso regression models) to YARH's self-reports of internet use. The YARH were aged 14-24 years old (N = 1287) from Los Angeles and New Orleans. Models were fit to three binary indicators of YARH's lifetime internet searches for general health, sexual and reproductive health (SRH), and social service information. YARH responses regarding internet health information seeking were fed into machine learning models with potential predictor variables based on findings from previous research, including sociodemographic characteristics, sexual and gender minority identity, healthcare access and engagement, sexual behavior, substance use, and mental health. About half of the YARH reported seeking general health and SRH information and 26% sought social service information. Areas under the ROC curve (≥ .75) indicated strong predictive models and results were consistent with the existing literature. For example, higher education and sexual minority identification was associated with seeking general health, SRH, and social service information. New findings also emerged. Cisgender identity versus transgender and non-binary identities was associated with lower odds of general health, SRH, and social service information seeking. Experiencing intimate partner violence was associated with higher odds of seeking general health, SRH, and social service information. Findings demonstrate the ability to develop predictive models to inform targeted health information dissemination strategies but underscore the need to better understand health disparities that can be operationalized as predictors in machine learning algorithms.

BackgroundThe COVID-19 pandemic illuminated the benefits of telemedicine. Self-collected specimens are a promising alternative to clinician-collected specimens when in-person testing is not feasible. In this study, we assessed the adequacy of self-collected pharyngeal and rectal specimens for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae among individuals undergoing chlamydia and gonorrhea screening.MethodsWe used data from a large cohort study that included male and female adolescents between the ages of 12-24 years. We considered self-collected specimens adequate for clinical use if the human synthase gene (a control target of the assay) was detected in the specimen.ResultsIn total, 2,458 specimens were included in the analysis. The human synthase gene was detected in 99.2% (2,439/2,458) of all self-collected specimens, 99.5% (1,108/1,114) of the pharyngeal specimens, and 99.0% (1,331/1,344) of the rectal specimens.ConclusionSelf-collected pharyngeal and rectal specimens demonstrated a very high proportion of human gene presence, suggesting that self-collection was accurate. A limitation of this study is that the sample adequacy control detects the presence or absence of the human hydroxymethylbilane synthase gene, but it does not indicate the specific anatomic origin of the human hydroxymethylbilane synthase gene. Self-collected specimens may be an appropriate alternative to clinician-collected specimens.

BackgroundPublic health organizations have inconsistent recommendations for screening adolescents and young adults for Chlamydia trachomatis (C. trachomatis) and Neisseria gonorrhoeae (N. gonorrhoeae) infections. Guidelines suggest different combinations of anorectal, pharyngeal, and urogenital testing based on age, sex, and sexual activity. Further evaluation of how identity and behaviors impact the anatomic distribution of C. trachomatis and N. gonorrhoeae infection is needed to optimize future screening practices.MethodsWe assessed the positivity of C. trachomatis and N. gonorrhoeae infections at different anatomic sites in a cohort of at-risk sexually active adolescents and young adults between 12-24 years old in New Orleans, Louisiana and Los Angeles, California. Participants were tested for C. trachomatis and N. gonorrhoeae at three sites (anorectum, pharynx, and urethral/cervix) every four months using self-collected swabs. We stratified anatomic distributions of infection into four gender and sexual behavior categories: (i) cisgender men who have sex with men and transgender women (MSMTW), (ii) cis-heterosexual males, (iii) cis-heterosexual females, and (iv) gender minorities assigned female at birth.ResultsWhile three-site testing detected all infections, two-site (anorectum and urethra/cervix) testing identified 92-100% of C. trachomatis or N. gonorrhoeae infections in participants assigned female at birth and cis-heterosexual males. For MSMTW, two site anorectal and pharyngeal testing versus single site anorectal testing increased the proportion of individuals with either infection from 74 to 93%.ConclusionSexual behavioral and gender identity factors may influence detection of C. trachomatis and N. gonorrhoeae infections at specific anatomic testing sites. Testing guidelines should incorporate sexual behavior and gender identity.

We examined whether the implementation of the Centers for Disease Control and Prevention's recommended screening of Chlamydia trachomatis/Neisseria gonorrhoeae with proactive follow-up among high-risk youth recruited from community and clinic settings reduced future C. trachomatis/N. gonorrhoeae diagnoses. After the Centers for Disease Control and Prevention's recommendations demonstrated a 41% decline in sexually transmitted infections; 3 tests in 1 year resulted in a 10% decline.

BackgroundGay, bisexual, transgender, and homeless youth are at risk of sexually transmitted infections. As part of an adolescent human immunodeficiency virus prevention study, we provided same-day Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) testing and treatment. We aimed to evaluate the feasibility and effectiveness of same-day CT and NG treatment on the proportion of participants receiving timely treatment.MethodsWe recruited adolescents with high sexual risk behaviors aged 12 to 24 years from homeless shelters, lesbian, gay, bisexual, and transgender organizations, and community health centers in Los Angeles, California, and New Orleans, Louisiana from May 2017 to June 2019. Initially, participants were offered point-of-care pharyngeal, rectal, and urethral/vaginal CT and NG testing and referral to another clinic for treatment. After March 2018 in Los Angeles and November 2018 in New Orleans, we provided same-day treatment (and partner treatment packs) for study participants. We measured the proportion of participants who received same-day treatment and the median time to treatment. We collected frequency of partner treatment and any reported adverse treatment-related events.ResultsThe proportion of participants receiving same-day CT and NG treatment increased from 3.6% (5/140) to 21.1% (20/95; Δ17.5%; 95% confidence interval, 9.2%-26.9%) after implementation of same-day testing and treatment. The median time to treatment decreased from 18.5 to 3 days. Overall, 36 participants took a total of 48 partner treatment packs. There were no reported treatment-related adverse events.ConclusionsProviding sexually transmitted infection treatment to adolescents at the same visit as testing is feasible and safe, and can increase the proportion of individuals receiving timely treatment.

Despite empirical support for "Self-control theory" in criminology, there is controversy about how self-control should be operationalized. Working within the framework of "self-control theory," we investigated if violence and criminal behaviors are associated with nine distinct dimensions of cognitive control in a community sample of young men (n = 654) living in peri-urban townships in South Africa. Cognitive control was assessed using the Behavior Rating Inventory of Executive Function. Multivariate statistical analysis was used, to identify associations between violence and criminality, and deaggregated measures of nine distinct components of cognitive control. Fifteen percent of the sample reported recent violence, 27% had been in physical fights with family/friends in the preceding 6 months, 10% reported being arrested, 4% reported forced sexual contact, and 26% reported intimate partner violence (IPV). Controlling for substance use and sociodemographic variables, contact with the criminal justice system and violence were associated with deficits in all domains of cognitive control. Forced sexual contact was associated with behavioral dysregulation. IPV was associated with behavior dysregulation and executive control dysfunction. Future studies might utilize deaggregated measures of self-control to provide further insight into links between particular components of cognitive control and various forms of offending and violence.

BackgroundRecent serogroup C meningococcal disease outbreaks led to meningococcal vaccine recommendations for Southern California men who have sex with men (MSM). Assessment of vaccine confidence is critical to improving vaccine coverage in the context of disease outbreaks wherein immunization(s) are recommended.MethodsWe surveyed MSM using venue-based sampling and began development of the vaccine confidence index (VCI) with 30 survey items corresponding to trust- and safety-related perceptions. We performed exploratory factor analyses and computed the Cronbach's alpha coefficient to assess internal consistency of the VCI. We created a categorical confidence variable (low, medium, and high confidence) and conducted bivariate and multivariate analyses to evaluate associations with reported confidence and immunization uptake.ResultsTen survey items were included in the final VCI and formed the confidence measure. Participants with low confidence had the lowest levels of reported uptake for both meningococcal vaccines. Confidence differed significantly (p ≤ 0.05) between MSM who indicated they received vaccines recommended within the context of the outbreak and those who did not.ConclusionsOur VCI is sensitive to a number of issues that may influence vaccine confidence. It is useful for assessing MSM trust and acceptance of recommended immunizations and may be used to inform intervention development.

We sought to identify the characteristics of men who have sex with men (MSM) who are opinion leaders on immunization issues and to identify potential opportunities to leverage their influence for vaccine promotion within MSM communities. Using venue-based sampling, we recruited and enrolled MSM living in Los Angeles (N = 520) from December 2016 to February 2017 and evaluated characteristic differences in sociodemographic characteristics, health behaviors, and technology use among those classified as opinion leaders versus those who were not. We also asked respondents about their past receipt of meningococcal serogroups A, C, W, and Y (MenACWY) and meningococcal B (MenB) vaccines, as well as their opinions on the importance of 13 additional vaccines. Multivariable results revealed that non-Hispanic black (aOR = 2.64; 95% CI: 1.17⁻5.95) and other race/ethnicity (aOR = 2.98; 95% CI: 1.41⁻6.29) respondents, as well as those with a history of an STI other than HIV (aOR = 1.95; 95% CI: 1.10⁻3.48), were more likely to be opinion leaders. MenACWY (aOR = 1.92; 95% CI: 1.13⁻3.25) and MenB (aOR = 3.09; 95% CI: 1.77⁻5.41) vaccine uptake, and perceived importance for these and seven additional vaccines, were also associated with being an opinion leader. The results suggest that the co-promotion of vaccination and other health promotion initiatives via opinion leaders could be a useful strategy for increasing vaccination among MSM.