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Dive into the research topics where Jonathan M. Ellen is active.

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Featured researches published by Jonathan M. Ellen.


AIDS | 2003

Environmental-structural factors significantly associated with consistent condom use among female sex workers in the Dominican Republic.

Deanna Kerrigan; Jonathan M. Ellen; Luis Moreno; Santo Rosario; Joanne Katz; David D. Celentano; Michael D. Sweat

Objective: To examine the influence of environmental-structural factors in promoting consistent condom use (CCU) among female sex workers (FSW) and their regular paying partners in the Dominican Republic. Methods: A cross-sectional survey was conducted with 288 FSW recruited from 41 sex establishments in Santo Domingo from March to June 1998. Sex workers were asked about their sexual behavior, self-efficacy at negotiating safe sex, perceived intimacy with their most recent regular paying partner, and the physical, social and policy environment of the establishment where they worked. Factor and reliability analysis were utilized to develop aggregate measures for self-efficacy (Cronbachs Alpha 0.60), intimacy (Cronbachs Alpha 0.80), and environmental-structural support (Cronbachs Alpha 0.72). Results: Controlling for sociodemographic characteristics of participants in multivariate analyses, environmental-structural support for condom use and HIV/sexually transmitted infection (STI) prevention was a significant predictor of CCU (OR 2.16; CI 1.18–3.97) among FSW and their regular paying partners. Safe sex self-efficacy (OR 2.80; CI 1.31–5.97) and low perceived intimacy with the most recent regular paying partner (OR 7.20; CI 3.49–14.83) were also significantly associated with CCU in multivariate analysis. Conclusion: Environmental-structural support for condom use and HIV/STI prevention is a significant predictor of CCU among FSW in the context of regular paying partnerships. Environmental-structural factors, in addition to relational and individual cognitive factors, should be assessed and addressed by behaviorally guided theory, research and interventions related to HIV/STI prevention and female sex work.


Sexually Transmitted Infections | 2002

Attitudes about sexual disclosure and perceptions of stigma and shame.

Shayna D. Cunningham; Jeanne M. Tschann; Jill E. Gurvey; J. D. Fortenberry; Jonathan M. Ellen

Objectives: To determine the association between stigma and shame about having a sexually transmitted disease and adolescents’ past STD related care seeking; between stigma, shame, and perceptions about disclosure of sexual behaviours to a doctor or nurse; and whether the association of stigma, shame, and care seeking was moderated by perceptions about disclosure. Methods: A household sample of 142 sexually active African-American youths, 13–19 years old, was questioned about STD related stigma (alpha = 0.89), STD related shame (alpha = 0.90), and perceptions about disclosure of sexual behaviours to a doctor or nurse (alpha = 0.81). Results: Among females, stigma was associated with increased anticipation of negative reactions to disclosure of sexual behaviours to a doctor or nurse (odds ratio (OR) = 0.319; 95% confidence interval (CI) =0.12 to 0.85) while shame was not. Stigma was also independently associated with STD related care seeking in the past year (OR = 0.296; 95% CI = 0.09 to 0.94) while shame was not. There was no association between stigma and shame with perceptions about disclosure or past care seeking in males. Perceived outcomes of disclosing sexual behaviours did not moderate the association of stigma, shame, and past STD related care seeking. Conclusions: Stigma about STDs may influence how female adolescents perceive reactions to disclosure of their sexual behaviour to healthcare providers. It may also be an important factor in their decision seek to STD related care. Perceptions about disclosure of sexual behaviour to a doctor or nurse do not change the relation of stigma or shame to past STD related care seeking.


JAMA | 2008

Interactions Between Secondhand Smoke and Genes That Affect Cystic Fibrosis Lung Disease

J. Michael Collaco; Lori Vanscoy; Lindsay Bremer; Kathryn McDougal; Scott M. Blackman; Amanda Bowers; Kathleen M. Naughton; Jacky M. Jennings; Jonathan M. Ellen; Garry R. Cutting

CONTEXT Disease variation can be substantial even in conditions with a single gene etiology such as cystic fibrosis (CF). Simultaneously studying the effects of genes and environment may provide insight into the causes of variation. OBJECTIVE To determine whether secondhand smoke exposure is associated with lung function and other outcomes in individuals with CF, whether socioeconomic status affects the relationship between secondhand smoke exposure and lung disease severity, and whether specific gene-environment interactions influence the effect of secondhand smoke exposure on lung function. DESIGN, SETTING, AND PARTICIPANTS Retrospective assessment of lung function, stratified by environmental and genetic factors. Data were collected by the US Cystic Fibrosis Twin and Sibling Study with missing data supplemented by the Cystic Fibrosis Foundation Data Registry. All participants were diagnosed with CF, were recruited between October 2000 and October 2006, and were primarily from the United States. MAIN OUTCOME MEASURES Disease-specific cross-sectional and longitudinal measures of lung function. RESULTS Of 812 participants with data on secondhand smoke in the home, 188 (23.2%) were exposed. Of 780 participants with data on active maternal smoking during gestation, 129 (16.5%) were exposed. Secondhand smoke exposure in the home was associated with significantly lower cross-sectional (9.8 percentile point decrease; P < .001) and longitudinal lung function (6.1 percentile point decrease; P = .007) compared with those not exposed. Regression analysis demonstrated that socioeconomic status did not confound the adverse effect of secondhand smoke exposure on lung function. Interaction between gene variants and secondhand smoke exposure resulted in significant percentile point decreases in lung function, namely in CFTR non-DeltaF508 homozygotes (12.8 percentile point decrease; P = .001), TGFbeta1-509 TT homozygotes (22.7 percentile point decrease; P = .006), and TGFbeta1 codon 10 CC homozygotes (20.3 percentile point decrease; P = .005). CONCLUSIONS Any exposure to secondhand smoke adversely affects both cross-sectional and longitudinal measures of lung function in individuals with CF. Variations in the gene that causes CF (CFTR) and a CF-modifier gene (TGFbeta1) amplify the negative effects of secondhand smoke exposure.


Aids and Behavior | 2007

The role of relationship intimacy in consistent condom use among female sex workers and their regular paying partners in the Dominican Republic

Laura K. Murray; Luis Moreno; Santo Rosario; Jonathan M. Ellen; Michael D. Sweat; Deanna Kerrigan

Prior research has demonstrated an important link between relationship intimacy and condom use. Limited research has been conducted on this connection within the realm of female sex work. We examined the association between perceived relationship intimacy and consistent condom use among 258 female sex workers and 278 male regular paying partners who participated in a cross-sectional survey in the Dominican Republic. In multivariate analysis, higher intimacy among sex workers and regular paying partners was negatively associated with consistent condom use. Among those reporting higher perceived intimacy, male participants were more than twice as likely to report consistent condom use as female participants. Female sex workers in relationships of higher perceived intimacy are at greater risk of HIV/AIDS than their male regular paying partners. Gender-sensitive HIV prevention programs are needed to address the differential influence of relationship intimacy on condom use in the context of sex work.


Sexually Transmitted Diseases | 2006

Sexual bridging socially and over time: A simulation model exploring the relative effects of mixing and concurrency on viral sexually transmitted infection transmission:

Irene A. Doherty; Stephen Shiboski; Jonathan M. Ellen; Adaora A. Adimora; Nancy S. Padian

Background: Sexual partnerships between people at higher and lower risk for sexually transmitted infections (STIs) (i.e., bridging) occur through dissortative mixing and concurrent partnerships, yet the relative effects of these network patterns on population STI spread are poorly understood. Goal: Using a stochastic model, the authors investigated the impact of mixing and concurrency on the spread of a persistent viral STI. Study Design: A total of 1050 populations were simulated of 1000 subjects over 400 weeks with varied concurrency levels and mixing patterns. STI prevalence and the average number of secondary transmissions per subject were analyzed with regression. Results: Mixing had a greater impact on prevalence for all groups, whereas concurrency was significant for only the lowest activity group. Mixing patterns moderated the magnitude of concurrency’s impact on secondary transmissions. Conclusions: Through connecting subgroups of differential risk, sexual mixing facilitates dissemination of STIs throughout a population. Concurrency expedites transmission by shortening the time between sexual contacts among infected and susceptible persons, particularly during the highly infectious period.


Social Science & Medicine | 2009

“Talking the talk, walking the walk: Social network norms, communication patterns, and condom use among the male partners of female sex workers in La Romana, Dominican Republic”

Clare Barrington; Carl A. Latkin; Michael D. Sweat; Luis Moreno; Jonathan M. Ellen; Deanna Kerrigan

Male partners of female sex workers are rarely targeted by HIV prevention interventions in the commercial sex industry, despite recognition of their central role and power in condom use negotiation. Social networks offer a naturally existing social structure to increase male participation in preventing HIV. The purpose of this study was to explore the relationship between social network norms and condom use among male partners of female sex workers in La Romana, Dominican Republic. Male partners (N =318) were recruited from 36 sex establishments to participate in a personal network survey. Measures of social network norms included 1) perceived condom use by male social network members and 2) encouragement to use condoms from social network members. Other social network characteristics included composition, density, social support, and communication. The primary behavioral outcome was consistent condom use by male partners with their most recent female sex worker partner during the last 3 months. In general, men reported small, dense networks with high levels of communication about condoms and consistent condom use. Multivariate logistic regression revealed consistent condom use was significantly more likely among male partners who perceived that some or all of their male social network members used condoms consistently. Perceived condom use was, in turn, significantly associated with dense networks, expressing dislike for condoms, and encouragement to use condoms from social network members. Findings suggest that the tight social networks of male partners may help to explain the high level of condom use and could provide an entry point for HIV prevention efforts with men. Such efforts should tap into existing social dynamics and patterns of communication to promote pro-condom norms and reduce HIV-related vulnerability among men and their sexual partners.


Journal of the Association of Nurses in AIDS Care | 2011

Transition of Adolescents With HIV to Adult Care: Characteristics and Current Practices of the Adolescent Trials Network for HIV/AIDS Interventions

Patricia P. Gilliam; Jonathan M. Ellen; Lori Leonard; Sara B. Kinsman; Cecilia M. Jevitt; Diane M. Straub

&NA; The transition process from pediatric to adult health care for adolescents with chronic diseases is always challenging and can be even more so for adolescents with HIV disease. The purpose of this study was to describe characteristics and current practices surrounding the transition of adolescents from the clinics of the Adolescent Trials Network for HIV/AIDS Interventions to adult medical care. This report focuses on the processes of transition, perceived barriers and facilitators, and anecdotal reports of successes and failures. Practice models used to assist adolescents during transition to adult medical care are described. Interviews were conducted with 19 key informants from 14 Adolescent Trials Network clinics. Findings revealed no consistent definition of “successful” transition, little consensus among the sites regarding specific elements of a transition program, and a lack of mechanisms to assess outcomes. Sites that viewed transition as a process rather than an event consistently described more structured program elements.


Journal of Adolescent Health | 2002

A randomized comparison of A-CASI and phone interviews to assess STD/HIV-related risk behaviors in teens

Jonathan M. Ellen; Jill E. Gurvey; Lauri A. Pasch; Jeanne M. Tschann; Joy Nanda; Joseph A. Catania

PURPOSE To compare response bias associated with a telephone survey of sexually transmitted disease/human immunodeficiency virus (STD/HIV)-related risk behaviors and an in-home self-administered audio computer assisted self interview (A-CASI). METHODS We randomly assigned an urban household sample of 223 African-American adolescents to a telephone interview or an A-CASI in their home. The sample was previously recruited by telephone for an earlier study regarding STDs and sexual behavior. We queried participants about their STD/HIV-related risk behaviors. We also assessed their perceived comfort, honesty, and accuracy in answering questions in the different modes through a telephone computer-assisted self-interview (T-CASI). RESULTS There were no significant differences by mode in percentages of participants reporting STD/HIV-related risk behaviors, except more A-CASI participants reported having engaged in sexual intercourse in past 3 months (43.8% vs. 33.3%). There were no differences in perceived comfort, honesty, and accuracy in answering questions in the different modes. These results also did not change after we adjusted for age, household structure, and current school enrollment. CONCLUSIONS Telephone interviews, a more economical mode, can be employed without much risk of increasing the response bias in the data assessing crude measures of risk.


The Journal of Infectious Diseases | 1997

An Investigation of Geographic Clustering of Repeat Cases of Gonorrhea and Chlamydial Infection in San Francisco, 1989–1993: Evidence for Core Groups

Jonathan M. Ellen; Nancy A. Hessol; Robert Kohn; Gail Bolan

To determine whether there were core groups of transmitters of gonorrhea and chlamydial infection among 14- to 35-year-olds in San Francisco during 1989-1993, sociodemographic risk factors for repeat gonorrhea and chlamydial infection were examined. During those 5 years, 8613 cases of gonorrhea were reported among males and 3893 among females; the proportions with repeat infection were 17.0% and 19.0%, respectively. There were also 2465 reported cases of chlamydial infection among males and 6996 among females; the proportions with repeat infection were 8.6% and 15.1%, respectively. Multivariate analyses reveal that for males, city planning region 5 was an independent risk factor for both repeat gonorrhea (relative hazard [RH] = 1.22; 95% confidence interval [CI] = 1.05-1.43) and repeat chlamydial infection (RH = 1.78; 95% CI = 1.23-2.57). For females, city planning region 4 was an independent risk factor for repeat gonorrhea (RH = 1.50; 95% CI = 1.12-1.98), and there was no high-risk planning region for repeat chlamydial infection. In San Francisco, there appear to be male and female core transmitters for gonorrhea but there may not be core transmitters for chlamydial infection.


Aids Patient Care and Stds | 2012

The impact of stigma on medication adherence among HIV-positive adolescent and young adult females and the moderating effects of coping and satisfaction with health care

Jaime Martinez; Gary W. Harper; Russell A. Carleton; Sybil Hosek; Kelly Bojan; Gretchen A. Clum; Jonathan M. Ellen

To explore whether HIV stigma negatively impacts adherence to antiviral medications in HIV-infected adolescent women, moderational analysis was conducted and factors identified that could alter said relationship. Study participants were 178 adolescent females age 15-24, enrolled between 2003-2005, from 5 different cities and 60 provided adherence information. Findings reported by this cohort of 60 adolescent women included: medication adherence, 64.3% reporting adherence at baseline and 45.0% at 12 months; HIV stigma score of 57.60 (standard deviation [SD], 11.83; range, 25-86). HIV stigma was not found to be a significant predictor when binary logit regression was run with medication adherence at 1 year. Using moderational analysis, factors that could moderate stigmas effect on medication adherence was still pursued and identified the following to be significant at 12 months: health care satisfaction (B = -0.020, standard error [SE] = 0.010, p < .05); and Coping (proactive coping strategies [B = 0.012, SE = 0.005, p < .05]; turning to family [B = 0.012, SE = 0.016, p < 0.05]; spiritual coping [B = 0.021, SE = 0.010, p < 0.05]; professional help [B = 0.021, SE = 0.010, p < 0.05]; physical diversions [B = 0.016, SE = 0.007, p < 0.05]). Factors that had no significant moderating effects included: social support measures (mean = 74.9; median = 74.0) and depression score greater than 16 = 43%. We conclude that HIV-infected adolescent women experience HIV stigma and poor adherence over time. Factors like health care satisfaction and coping may minimize stigmas effect on medication adherence. Our findings are tempered by a small sample size and lack of a direct relationship between stigma and adherence on binary logit regression analysis.

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Maria Trent

Johns Hopkins University

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Nancy Willard

Johns Hopkins University

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Shang En Chung

Johns Hopkins University

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Bill G. Kapogiannis

National Institutes of Health

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Nancy E. Adler

University of California

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