Factors Associated With Human Immunodeficiency Virus Infections Linked in Genetic Clusters But Disconnected in Partner Tracing.

BACKGROUND: Successful partner notification can improve community-level outcomes by increasing the proportion of persons living with human immunodeficiency virus (HIV) who are linked to HIV care and virally suppressed, but it is resource intensive. Understanding where HIV transmission pathways may be undetected by routine partner notification may help improve case finding strategies. METHODS: We combined partner notification interview and HIV sequence data for persons diagnosed with HIV in Wake County, NC in 2012 to 2013 to evaluate partner contact networks among persons with HIV pol gene sequences 2% or less pairwise genetic distance. We applied a set of multivariable generalized estimating equations to identify correlates of disparate membership in genetic versus partner contact networks. RESULTS: In the multivariable model, being in a male-male pair (adjusted odds ratio [AOR], 16.7; P = 0.01), chronic HIV infection status (AOR, 4.5; P < 0.01), and increasing percent genetic distance between each dyad member's HIV pol gene sequence (AOR, 8.3 per each 1% increase, P < 0.01) were all associated with persons with HIV clustering but not being identified in the partner notification network component. Having anonymous partners or other factors typically associated with risk behavior were not associated. CONCLUSIONS: Based on genetic networks, partnerships which may be stigmatized, may have occurred farther back in time or may have an intervening partner were more likely to be unobserved in the partner contact network. The HIV genetic cluster information contributes to public health understanding of HIV transmission networks in these settings where partner identifying information is not available.

Efficacy of the Young Women's CoOp: An HIV Risk-Reduction Intervention for Substance-Using African-American Female Adolescents in the South.

HIV/sexually transmitted infection (STI) risk-reduction interventions are needed to address the complex risk behaviors among African-American female adolescents in disadvantaged communities in North Carolina. In a two-group randomized trial, we reached 237 sexually active, substance-using African-American female adolescents, to test a risk-reduction intervention, the Young Women's CoOp (YWC), relative to a nutrition control. In efficacy analyses adjusting for baseline condom use, at three-month follow-up participants in the YWC were significantly less likely to report sex without a condom at last sex relative to control. There were mixed findings for within-group differences over follow-up, underscoring the challenges for intervening with substance-using female youths.

Seek, Test and Disclose: knowledge of HIV testing and serostatus among high-risk couples in a South African township.

OBJECTIVES: HIV testing and disclosure of results to partners is an important strategy in HIV prevention but is under-researched within heterosexual partnerships. To address this gap, we describe patterns of HIV testing, discrepancies between beliefs and biologically confirmed HIV status of each partner, and characteristics of mutually correct knowledge of HIV status among heterosexual couples in a high-prevalence community. METHODS: The study recruited 290 high-risk heterosexual couples in stable relationships from a township in Cape Town, South Africa. Male patrons of shebeens (drinking establishments) were approached to participate with their main partner in an intervention designed to reduce substance use, violence and unsafe sex. All participants were tested for HIV at baseline and asked about their partner's past HIV testing and current status. Using the couple as the unit of analysis, we conducted logistic regression to identify partnership and individual characteristics associated with having mutually correct knowledge of partner's HIV status. RESULTS: Half (52%) of women and 41% of men correctly knew whether their partner had ever been tested for HIV. 38% of women, 28% of men and in 17% of couples, both members reported mutually correct knowledge of their partner's HIV status. Correlates of correct knowledge included married/cohabitating (aOR 2.69, 95% CI 1.35 to 5.40), both partners HIV-negative (aOR 3.32 (1.38 to 8.00)), women's acceptance of traditional gender roles (aOR 1.17 (1.01 to 1.40)) and men's relationship satisfaction (aOR 2.22 (1.01 to 4.44)). CONCLUSIONS: Findings highlight the need to improve HIV testing uptake among men and to improve HIV disclosure among women in heterosexual partnerships. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov registration NCT01121692.

Event-level analyses of sex-risk and injection-risk behaviors among nonmedical prescription opioid users.

BACKGROUND: Nonmedical prescription opioid use has been linked to hepatitis C virus (HCV) infection among people who inject drugs and with using high dead space syringes that retain more blood and transfer more HIV if shared. Little is known regarding its effects on sex-risk behaviors. OBJECTIVES: This paper examines event-level associations between nonmedical prescription opioid use and sharing high dead space syringes (injection risk) and unprotected intercourse (sex risk) behaviors. METHODS: We recruited 1,985 participants from two overlapping risk groups-drug users and men who have sex with men (MSM)-and their sex partners. Participants completed an interview that included event-level sex questions with recent sex partners and injection questions with recent injection partners. We used multivariable generalized estimating equations (GEE) to assess the associations between nonmedical prescription opioid use and unprotected intercourse during sexual encounters and sharing syringes during injection episodes, while adjusting for within-person correlations. RESULTS: When both partners used nonmedical prescription opioids, its use was independently associated with unprotected intercourse in sexual encounters (OR = 2.24; 95% CI = 1.12, 4.49). The use of nonmedical prescription opioids was also associated with sharing high dead space syringes during injection episodes (OR = 6.57; 95% CI = 1.63, 26.51). CONCLUSION: Nonmedical prescription opioid use is associated with an increase in the risk of unprotected sex and sharing high dead space syringes. HIV and HCV prevention interventions for nonmedical prescription opioid users should address sex-risk behaviors and encourage the use of acceptable low dead space needles and syringes.

Characteristics of African American Women and Their Partners With Perceived Concurrent Partnerships in 4 Rural Counties in the Southeastern U.S.

BACKGROUND: To the individual with concurrent partners, it is thought that having concurrent partnerships confers no greater risk of acquiring HIV than having multiple consecutive partnerships. However, an individual whose partner has concurrent partnerships (partner's concurrency) is at increased risk for incident HIV infection. We sought to better understand relationships characterized by partner's concurrency among African American women. METHODS: A total of 1013 African American women participated in a cross-sectional survey from 4 rural Southeastern counties. RESULTS: Older age at first sex was associated with lower prevalence of partner's concurrency (prevalence ratio, 0.70; 95% confidence interval, 0.57-0.87), but the participant's age was not associated with partner's concurrency. After adjusting for covariates, ever having experienced intimate partner violence (IPV) and forced sex were most strongly associated with partner's concurrency (prevalence ratios, 1.61 [95% confidence intervals, 1.23-2.11] and 1.65 [1.20-2.26], respectively). Women in mutually monogamous partnerships were the most likely to receive economic support from their partners; women whose partners had concurrent partnerships did not report more economic benefit than did those whose partners were monogamous. CONCLUSIONS: Associations between history of IPV and forced sex with partner's concurrency suggest that women with these experiences may particularly benefit from interventions to reduce partner's concurrency in addition to support for reducing IPV and other sexual risks. To inform these interventions, further research to understand partnerships characterized by partner's concurrency is warranted.

Perceived need for substance use treatment among young women from disadvantaged communities in Cape Town, South Africa.

BACKGROUND: Initiation of treatment for substance use disorders is low among young women from disadvantaged communities in Cape Town, South Africa. Yet little is known about the factors that influence perceived need for treatment (a determinant of treatment entry) within this population. METHODS: Baseline data on 720 young, drug-using women, collected as part of a randomized field experiment were analyzed to identify predisposing, enabling and health need factors associated with perceived need for treatment. RESULTS: Overall, 46.0% of our sample perceived a need for treatment. Of these participants, 92.4% wanted treatment for their substance use problems but only 50.1% knew where to access services. In multivariable logistic regression analyses, we found significant main effects for ethnicity (AOR = 1.54, 95% CI = 1.05-1.65), income (AOR = 0.96, 95% CI = 0.93-0.99), anxiety (AOR = 1.22, 95% CI = 1.05-1.45), and not having family members with drug problems (AOR = 1.45, 95% CI = 1.05-2.04) on perceived need for treatment. When the sample was stratified by methamphetamine use, income (AOR = 0.87, 95% CI = 0.79-0.96), awareness of treatment services (AOR =1.84, 95% CI = 1.03-3.27), anxiety (AOR =1.41, 95% CI = 1.06-1.87) and physical health status (AOR = 6.29, 95% CI = 1.56-25.64) were significantly associated with perceived need for treatment among those who were methamphetamine-negative. No variables were significantly associated with perceived need for treatment among participants who were methamphetamine-positive. CONCLUSIONS: A sizeable proportion of young women who could benefit from substance use treatment do not believe they need treatment, highlighting the need for interventions that enhance perceived need for treatment in this population. Findings also show that interventions that link women who perceive a need for treatment to service providers are needed. Such interventions should address barriers that limit young women's use of services for substance use disorders.

The biobehavioral Women's Health CoOp in Pretoria, South Africa: study protocol for a cluster-randomized design.

BACKGROUND: South Africa has 6.4 million adults over the age of 15 living with HIV. Gender inequality issues continue to drive the HIV epidemic in South Africa, where Black African women bear the greatest HIV burden. Limited access to services; little capacity to negotiate sex and condom use; and other legal, social, and economic inequities make women highly vulnerable to HIV infection. Behavioral interventions have been shown to decrease risk behaviors, but they have been less successful in reducing HIV incidence. Conversely, biomedical prevention strategies have proven to be successful in reducing HIV incidence, but require behavioral interventions to increase uptake and adherence. Consequently, there is a need for integrated approaches that combine biomedical and behavioral interventions. Effective combination prevention efforts should comprise biomedical, behavioral, and structural programming proven in randomized trials that focuses on the driving forces and key populations at higher risk of HIV infection and transmission. METHODS/DESIGN: This prospective, geographically clustered randomized field experiment is enrolling participants into two arms: a control arm that receives standard HIV testing and referral for treatment; and an intervention arm that receives an evidence-based, woman-focused behavioral intervention that emphasizes risk reduction and retention, the Women's Health CoOp. We divided the city of Pretoria into 14 mutually exclusive geographic zones and randomized these zones into either the control arm or the intervention arm. Outreach workers are recruiting drug-using women from each zone. At baseline, eligible participants complete a questionnaire and biological testing for HIV, recent drug use, and pregnancy. Follow-up interviews are completed at 6 and 12 months. DISCUSSION: The biobehavioral intervention in this study merges an efficacious behavioral HIV prevention intervention for women with biomedical prevention through HIV treatment as prevention using a Seek, Test, Treat and Retain strategy. This combination biobehavioral intervention is designed to (1) improve the quality of life and reduce HIV infectiousness among women who are HIV positive, and (2) reduce HIV risk behaviors among women regardless of their HIV status. If efficacious, this intervention could help control the HIV epidemic in South Africa. TRIAL REGISTRATION: Trial registration no: NCT01497405.

From coitus to concurrency: sexual partnership characteristics and risk behaviors of 15-19 year old men recruited from urban venues in Tanzania.

Understanding the uptake and patterns of sexual partnerships of adolescent males reveals their risky behaviors that could persist into adulthood. Using venue-based sampling, we surveyed 671 male youth ages 15-19 from an urban Tanzanian neighborhood about their sexual partnerships during the past 6 months. The proportion of males who had ever had sex increased with age (21 % at age 15; 70 % at age 17; 94 % at age 19), as did the proportion who engaged in concurrency (5 % at age 15; 28 % at age 17; 44 % at age 19). Attendance at ≥2 social venues per day and meeting a sexual partner at a venue was associated with concurrency. Concurrency was associated with alcohol consumption before sex among 18-19 year olds and with not being in school among 15-17 year olds. We find that concurrency becomes normative over male adolescence. Venue-based sampling may reach youth vulnerable to developing risky sexual partnership patterns.

Food Insecurity in the Rural South in the Wake of the COVID-19 Pandemic.

Food insecurity in rural communities in the Southern US continues to grow, especially in the wake of the COVID-19 pandemic. Understanding the characteristics of food-insecure individuals and families in this region is critical for developing creative strategies for eliminating this health disparity issue. A food insecurity survey was given to attendees at food-security events held in several counties in one Southern US state. A descriptive analysis of food insecurity in this region is presented, and recommendations for addressing food insecurity among underserved and disadvantaged populations are suggested.

Sexual networks, surveillance, and geographical space during syphilis outbreaks in rural North Carolina.

BACKGROUND: Sexually transmitted infections (STIs) spread along sexual networks whose structural characteristics promote transmission that routine surveillance may not capture. Cases who have partners from multiple localities may operate as spatial network bridges, thereby facilitating geographical dissemination. We investigated how surveillance, sexual networks, and spatial bridges relate to each other for syphilis outbreaks in rural counties of North Carolina. METHODS: We selected from the state health department's surveillance database cases diagnosed with primary, secondary, or early latent syphilis during October 1998 to December 2002 and who resided in central and southeastern North Carolina, along with their sex partners and their social contacts irrespective of infection status. We applied matching algorithms to eliminate duplicate names and create a unique roster of partnerships from which networks were compiled and graphed. Network members were differentiated by disease status and county of residence. RESULTS: In the county most affected by the outbreak, densely connected networks indicative of STI outbreaks were consistent with increased incidence and a large case load. In other counties, the case loads were low with fluctuating incidence, but network structures suggested the presence of outbreaks. In a county with stable, low incidence and a high number of cases, the networks were sparse and dendritic, indicative of endemic spread. Outbreak counties exhibited densely connected networks within well-defined geographic boundaries and low connectivity between counties; spatial bridges did not seem to facilitate transmission. CONCLUSIONS: Simple visualization of sexual networks can provide key information to identify communities most in need of resources for outbreak investigation and disease control.

The 5Ws of Racial Equity in Research: A Framework for Applying a Racial Equity Lens Throughout the Research Process.

Ensuring equity in research is a critical step in advancing health equity. In this perspective, the authors introduce a guiding framework for advancing racial equity in research processes, environments, and among the research workforce, the 5Ws of Racial Equity in Research. Centering their discussion on the 5Ws: Who, What, When, Where, and Why, they use historical and contemporary examples of research inequities to demonstrate how these five simple questions can encourage open discussion and proactive planning for equity in research. They close with an acknowledgment of the framework's broad utility and a researcher-directed call to action.

Sexual networks and sexually transmitted infections: innovations and findings.

PURPOSE OF REVIEW: With increasing recognition of the importance of sexual networks in the dissemination of sexually transmitted infections (STIs), research is expanding. This review focuses on methodology for conducting sexual network research with in-depth presentations of recent and novel studies conducted on four continents. RECENT FINDINGS: Studies in diverse settings such as rural villages of China and St. Petersburg, Russia offer compelling evidence that HIV is no longer confined to needle-sharing and drug-using networks, but has diffused into the general population via heterosexual transmission. Because the networks are not especially densely connected, the shift will happen slowly. In contrast, studies conducted on both the east and west coasts of the US among men who have sex with men and women show that, despite high HIV prevalence, substance abuse, homelessness, and unprotected anal intercourse, the size of the population and sexual network dynamics are insufficient to cause widespread heterosexual HIV transmission. In Africa, holding low-risk positions in sexual networks can elevate the risk of infection, whereas higher-risk partnerships also simultaneously affect HIV transmission. SUMMARY: The diversity of findings in a diversity of settings demonstrates that not all networks operate in similar ways.

Comparison of sexual mixing patterns for syphilis in endemic and outbreak settings.

BACKGROUND: In a largely rural region of North Carolina during 1998-2002, outbreaks of heterosexually transmitted syphilis occurred, tied to crack cocaine use and exchange of sex for drugs and money. Sexual partnership mixing patterns are an important characteristic of sexual networks that relate to transmission dynamics of sexually transmitted infections (STIs). METHODS: Using contact tracing data collected by disease intervention specialists, we estimated Newman assortativity coefficients and compared values in counties experiencing syphilis outbreaks to nonoutbreak counties, with respect to race/ethnicity, race/ethnicity and age, and the cases' number of social/sexual contacts, infected contacts, sex partners, and infected sex partners, and syphilis disease stage (primary, secondary, early latent). RESULTS: Individuals in the outbreak counties had more contacts and mixing by the number of sex partners was disassortative in outbreak counties and assortative nonoutbreak counties. Although mixing by syphilis disease stage was minimally assortative in outbreak counties, it was disassortative in nonoutbreak areas. Partnerships were relatively discordant by age, especially among older white men, who often chose considerably younger female partners. CONCLUSIONS: Whether assortative mixing exacerbates or attenuates the reach of STIs into different populations depends on the characteristic/attribute and epidemiologic phase. Examination of sexual partnership characteristics and mixing patterns offers insights into the growth of STI outbreaks that complement other research methods.

Coparenting and sexual partner concurrency among white, black, and Hispanic men in the United States.

BACKGROUND: Concurrent sexual partnerships (partnerships that overlap in time) increase the spread of infection through a network. Different patterns of concurrent partnerships may be associated with varying sexually transmitted infection (STI) risk depending on the partnership type (primary vs. nonprimary) and the likelihood of condom use with each concurrent partner. We sought to evaluate coparenting concurrency, overlapping partnerships in which at least 1 concurrent partner is a coparent with the respondent, which may promote the spread of STIs. METHODS: We examined sexual partnership dates and fertility history of 4928 male respondents in the 2002 National Survey of Family Growth. We calculated coparenting concurrency prevalence and examined correlates using Poisson regression. RESULTS: Among men with ≤ 1 pair of concurrent partnerships, 18% involved a coparent. 33% of black men involved in coparenting concurrency were <25 years, compared to 23% of Hispanics and 6% of whites. Young black men (age, 15-24 years) were more likely to engage in coparenting concurrency than white men, adjusting for sociodemographic characteristics, sexual and other high-risk behaviors, and relationship quality. Compared to white men aged 15 to 24 years, black and Hispanic men were 4.60 (95% confidence interval: 1.10, 19.25) and 3.45 (95% confidence interval: 0.64, 18.43) times as likely to engage in coparenting concurrency. CONCLUSION: Almost 1 in 5 men engaging in concurrent sexual partnerships in the past year was a coparent with at least one of the concurrent partners. Understanding the context in which different types of concurrency occur will provide a foundation on which to develop interventions to prevent STIs.

Lost and found: applying network analysis to public health contact tracing for HIV.

Infectious disease surveillance is often case-based, focused on people diagnosed and their contacts in a predefined time window, and treated as independent across infections. Network analysis of partners and contacts joining multiple investigations and infections can reveal social or temporal trends, providing opportunities for epidemic control within broader networks. We constructed a sociosexual network of all HIV and early syphilis cases and contacts investigated among residents of 11 contiguous counties in North Carolina over a two-year period (2012-2013). We anchored the analysis on new HIV diagnoses ("indexes"), but also included nodes and edges from syphilis investigations that were within the same network component as any new HIV index. After adding syphilis investigations and deduplicating people included in multiple investigations (entity resolution), the final network comprised 1470 people: 569 HIV indexes, 700 contacts to HIV indexes who were not also new cases themselves, and 201 people who were either indexes or contacts in eligible syphilis investigations. Among HIV indexes, nearly half (48%; n = 273) had no located contacts during single-investigation contact tracing, though 25 (9%) of these were identified by other network members and thus not isolated in the final multiple investigation network. Constructing a sociosexual network from cases and contacts across multiple investigations mitigated some effects of unobserved partnerships underlying the HIV epidemic and demonstrated the HIV and syphilis overlap in these networks.

COVID-19 vaccine hesitancy in underserved communities of North Carolina.

BACKGROUND: In the United States, underserved communities including Blacks and Latinx are disproportionately affected by COVID-19. This study sought to estimate the prevalence of COVID-19 vaccine hesitancy, describe attitudes related to vaccination, and identify correlates among historically marginalized populations across 9 counties in North Carolina. METHODS: We conducted a cross-sectional survey distributed at free COVID-19 testing events in underserved rural and urban communities from August 27 -December 15, 2020. Vaccine hesitancy was defined as the response of "no" or "don't know/not sure" to whether the participant would get the COVID-19 vaccine as soon as it became available. RESULTS: The sample comprised 948 participants including 27.7% Whites, 59.6% Blacks, 12.7% Latinx, and 63% female. 32% earned <$20K annually, 60% owned a computer and ~80% had internet access at home. The prevalence of vaccine hesitancy was 68.9% including 62.7%, 74%, and 59.5% among Whites, Blacks, and Latinx, respectively. Between September and December, the largest decline in vaccine hesitancy occurred among Whites (27.5 percentage points), followed by Latinx (17.6) and only 12.0 points among Blacks. 51.2% of respondents reported vaccine safety concerns, 23.7% wanted others to get vaccinated first, and 63.1% would trust health care providers about the COVID-19 vaccine. Factors associated with hesitancy in multivariable logistic regression included being female (OR = 1.90 95%CI [1.36, 2.64]), being Black (OR = 1.68 1.16, 2.45]), calendar month (OR = 0.76 [0.63, 0.92]), safety concerns (OR = 4.28 [3.06, 5.97]), and government distrust (OR = 3.57 [2.26, 5.63]). CONCLUSIONS: This study engaged the community to directly reach underserved minority populations at highest risk of COVID-19 that permitted assessment of vaccine hesitancy (which was much higher than national estimates), driven in part by distrust, and safety concerns.

COVID-19 Vaccine Hesitancy in Underserved Communities of North Carolina.

BACKGROUND: In the United States, underserved communities including Blacks and Latinx are disproportionately affected by COVID-19, and widespread vaccination is critical for curbing this pandemic. This study sought to estimate the prevalence of COVID-19 vaccine hesitancy, describe attitudes related to vaccination, and identify correlates among racial minority and marginalized populations across 9 counties in North Carolina. METHODS: We conducted a cross-sectional survey with a self-administered questionnaire distributed at free COVID-19 testing events in underserved rural and urban communities from August 27 - December 15, 2020. Vaccine hesitancy was defined as the response of "no" or "don't know/not sure" to whether the participant would get the COVID-19 vaccine as soon as it became available. RESULTS: The sample comprised 948 participants including 27.7% Whites, 59.6% Blacks, 12.7% Latinx, and 63% female. Thirty-two percent earned <$20K annually, 60% owned a computer and ∼80% had internet access at home. The prevalence of vaccine hesitancy was 68.9% including 62.7%, 74%, and 59.5% among Whites, Blacks, and Latinx, respectively. Between September and December, the largest decline in vaccine hesitancy occurred among Whites (27.5 percentage points), followed by Latinx (17.6) and the smallest decline was among Black respondents (12.0). 51.2% of the respondents reported vaccine safety concerns, 23.7% wanted others to get of the respondents reported they would trust health care providers with information about the COVID-19 vaccine. Factors associated with hesitancy in multivariable logistic regression included being female (OR=1.90 95%CI[1.36, 2.64]), being Black (OR=1.68 [1.106 2.45]), calendar month (OR=0.76 [0.63, 0.92]), safety concerns (OR=4.28 [3.06, 5.97]), and government distrust (OR=3.57 [2.26, 5.63]). CONCLUSIONS: This study reached underserved minority populations in a number of different locations to investigate COVID-19 vaccine hesitancy. We built on existing relationships and further engaged the community, stake holders and health department to provide free COVID-19 testing. This direct approach permitted assessment of vaccine hesitancy (which was much higher than national estimates), distrust, and safety concerns. HIGHLIGHTS: This study surveyed 948 adults at COVID-19 testing sites in 9 counties of North Carolina between August 27 and December 15, 2020 where vaccine hesitancy was widespread including 74% in Blacks, 62.7% in Whites and 59.5% in Latinx.Vaccine hesitancy declined over time but remained high for Blacks.On-site surveys conducted in underserved areas that were paper-based and self-administered permitted reaching adults with no internet (17%), no cell phone (20%), no computer (40%) and yearly incomes less than 20K (31%).Widespread vaccine hesitancy in predominately minority communities of NC must be addressed to successfully implement mass COVID-19 vaccination programs.

Mapping health data: improved privacy protection with donut method geomasking.

A major challenge in mapping health data is protecting patient privacy while maintaining the spatial resolution necessary for spatial surveillance and outbreak identification. A new adaptive geomasking technique, referred to as the donut method, extends current methods of random displacement by ensuring a user-defined minimum level of geoprivacy. In donut method geomasking, each geocoded address is relocated in a random direction by at least a minimum distance, but less than a maximum distance. The authors compared the donut method with current methods of random perturbation and aggregation regarding measures of privacy protection and cluster detection performance by masking multiple disease field simulations under a range of parameters. Both the donut method and random perturbation performed better than aggregation in cluster detection measures. The performance of the donut method in geoprivacy measures was at least 42.7% higher and in cluster detection measures was less than 4.8% lower than that of random perturbation. Results show that the donut method provides a consistently higher level of privacy protection with a minimal decrease in cluster detection performance, especially in areas where the risk to individual geoprivacy is greatest.

Geomasking sensitive health data and privacy protection: an evaluation using an E911 database.

Geomasking is used to provide privacy protection for individual address information while maintaining spatial resolution for mapping purposes. Donut geomasking and other random perturbation geomasking algorithms rely on the assumption of a homogeneously distributed population to calculate displacement distances, leading to possible under-protection of individuals when this condition is not met. Using household data from 2007, we evaluated the performance of donut geomasking in Orange County, North Carolina. We calculated the estimated k-anonymity for every household based on the assumption of uniform household distribution. We then determined the actual k-anonymity by revealing household locations contained in the county E911 database. Census block groups in mixed-use areas with high population distribution heterogeneity were the most likely to have privacy protection below selected criteria. For heterogeneous populations, we suggest tripling the minimum displacement area in the donut to protect privacy with a less than 1% error rate.

Think Inside the Box: the Heterogeneity of "in Risk" Among "at Risk" Female African American Adolescents in North Carolina.

INTRODUCTION: An abundance of research investigates the health of often referred to as "at risk" or "high risk" youth from underserved communities and usually racial/ethnic minorities. These ubiquitous terms relate to poverty, violence, and unsafe behaviors (e.g., sex without condoms, alcohol, and drug use). METHODS: This analysis distinguished the heterogeneity of risks among African American female adolescents recruited for an intervention study from underserved communities in North Carolina. Eligibility included: ages 16-19, considered or dropped out of school, never completed high school, and during the past 3 months had sex with a male partner and used drugs or alcohol. A variable was created to represent the continuum of risk comprised of history of homelessness, or trading sex, or current heavy alcohol and marijuana use. Participants fell into 0, 1, or 2-3 categories. Ordinal logistic regression estimated the odds of adverse poor outcomes by category. Linear regression estimated reduction in material and emotional support by category. RESULTS: Of the 237 participants, 59.5%, 27.8%, and 12.7% were in 0, 1, or 2-3 categories, respectively. Relative to adolescents in 0 categories, participants in other categories were more likely to report food insecurity (OR = 3.27, 95%CI [1.8, 5.94]); past arrest (OR = 3.56 [2.08, 6.09]); run away (OR = 3.30 [1.79, 6.10]); multiple sex partners (2.97 [1.61, 5.48]); and vaginal/anal sexual abuse (OR = 3.21[1.73, 5.96]). Material and emotional support was significantly lower for participants in 2-3 risk categories. CONCLUSIONS: Vague use of "at risk" fails to recognize the heterogeneity of experiences and needs of underserved African American youth.