We evaluated the effects of a culturally adapted evidence-based HIV prevention intervention (Mpow... more We evaluated the effects of a culturally adapted evidence-based HIV prevention intervention (Mpowerment), named “Tayf”, on condom use and HIV testing among young men who have sex with men (YMSM) in Beirut. A 2-year implementation of Tayf was carried out independently and in parallel with a research cohort of 226 YMSM who were surveyed at baseline and months 6, 12, 18 and 24 after Tayf initiation. Primary outcomes were (1) any condomless anal sex with HIV-positive or unknown status partners in the past 3 months, and (2) HIV testing in the past six months. Hierarchical logistic regression models examined the association of Tayf participation with the outcomes averaged across all assessments, and the moderating effect of Tayf participation on change in the outcomes over the follow-up period. A total of 331 YMSM attended at least one event, including 33% of the cohort. Tayf participation was associated with a higher rate of any condomless sex with HIV-positive or unknown status partners...
In 2012, our research with young men who have sex with men (YMSM) in Beirut showed high rates of ... more In 2012, our research with young men who have sex with men (YMSM) in Beirut showed high rates of recent condomless anal sex and low rates of recent HIV testing. In 2017, we collected data from YMSM to assess for temporal changes and sociodemographic correlates. Propensity score weighting was used to eliminate any sociodemographic differences between the 2012 ( n = 164) and 2017 ( n = 226) samples of YMSM (age 18–29) recruited with long-chain peer referral sampling. Regression analysis was used to examine sociodemographic correlates of recent condomless anal sex and HIV testing using the 2017 sample, and whether these behaviors differed between the samples. Compared to the 2012 sample, the 2017 sample was about half as likely to report any condomless anal sex in the past 3 months with partners whose HIV status was positive or unknown (14% vs. 23%; OR [95%CI] 0.56 [0.32, 0.98]), and nearly 2.5 times as likely to report HIV testing in the past 6 months (48% vs. 27%; OR [95%CI] 2.44 [1.46, 4.10]). In the 2017 sample, any recent condomless anal sex with partners whose HIV status was positive or unknown was associated with employment and Christian religious affiliation. Low income was the sole correlate of having recently tested for HIV. These findings suggest a temporal trend toward increased HIV protective behaviors among YMSM in Beirut over the past 5 years. Further inroads could be secured if HIV prevention programming targeted economic influences.
Bullying and homophobic teasing behaviors affect the lives of many school aged children, often co... more Bullying and homophobic teasing behaviors affect the lives of many school aged children, often co-occur, and tend to peak in middle school. While bullying and homophobic teasing behaviors are known to be peer group phenomena, studies typically examine the associations at the individual or school levels. An examination of these behaviors at the peer group level can aid in our understanding of the formation and maintenance of peer groups that engage in these forms of aggressive behavior (selection), and the extent to which friends and the peer group impact individual rates of these aggressive behaviors (influence). In this longitudinal study, we assess the co-evolution of friendship networks, bullying perpetration, and homophobic teasing among middle school students (n = 190) using a Stochastic Actor-Based Model (SABM) for longitudinal networks. Data were collected from 6-8th-grade students (Baseline age 12-15; 53% Female; 47% Male) across three waves of data. The sample was diverse w...
Journal of acquired immune deficiency syndromes (1999), Jan 7, 2018
and SettingBlack men who have sex with men (MSM) in the United States (U.S.) have disproportionat... more and SettingBlack men who have sex with men (MSM) in the United States (U.S.) have disproportionately high HIV infection rates. Social networks have been shown to influence HIV risk behavior; however, little is known about whether they affect the risk of HIV seroconversion. This study uses data from the BROTHERS (HPTN 061) study to test whether contextual factors related to social networks are associated with HIV seroconversion among black MSM.MethodsWe analyzed data from the BROTHERS study (2009-2011), which examined a multi-component intervention for black MSM in 6 U.S. cities. We ran a series of Cox regression analyses to examine associations between time-dependent measures of network support (personal/emotional, financial, medical, and social participation) and time to HIV seroconversion. We ran unadjusted models followed by models adjusted for participant age at enrollment and study location.ResultsA total of 1000 black MSM tested HIV negative at baseline and were followed at 6-...
To understand the process of practice transformation by identifying pathways for attaining patien... more To understand the process of practice transformation by identifying pathways for attaining patient-centered medical home (PCMH) recognition. The CMS Federally Qualified Health Center (FQHC) Advanced Primary Care Practice Demonstration was designed to help FQHCs achieve NCQA Level 3 PCMH recognition and improve patient outcomes. We used a stratified random sample of 20 (out of 503) participating sites for this analysis. We developed a conceptual model of structural, cultural, and implementation factors affecting PCMH transformation based on literature and initial qualitative interview themes. We then used conventional cross-case analysis, followed by qualitative comparative analysis (QCA), a cross-case method based on Boolean logic algorithms, to systematically identify pathways (i.e., combinations of factors) associated with attaining-or not attaining-Level 3 recognition. Site-level indicators were derived from semistructured interviews with site leaders at two points in time (mid- ...
The Journal of adolescent health : official publication of the Society for Adolescent Medicine, Jan 4, 2016
Homophobic victimization, and specifically name-calling, has been associated with greater psychol... more Homophobic victimization, and specifically name-calling, has been associated with greater psychological distress and alcohol use in adolescents. This longitudinal study examines whether sexual orientation moderates these associations and also differentiates between the effects of name-calling from friends and nonfriends. Results are based on 1,325 students from three Midwestern high schools who completed in-school surveys in 2012 and 2013. Linear regression analysis was used to examine the associations among homophobic name-calling victimization and changes in anxiety symptoms, depressive symptoms, and alcohol use one year later, controlling for other forms of victimization and demographics. Homophobic name-calling victimization by friends was not associated with changes in psychological distress or alcohol use among either students who self-identified as heterosexual or those who self-identified as lesbian, gay, or bisexual (LGB). In contrast, homophobic name-calling by nonfriends ...
With marijuana use increasing among American adolescents, better understanding of the factors ass... more With marijuana use increasing among American adolescents, better understanding of the factors associated with decreasing use and quitting can help inform cessation efforts. This study evaluates a range of neighborhood, family, peer network, and individual factors as predictors of marijuana use, change, and non-use over one year, and cessation over six years. Data come from adolescents in Waves I and II of the National Longitudinal Study of Adolescent Health (N=458, one-year sample), or Waves I and III (N=358, six-year sample), and reported using marijuana at least four times in the past month at Wave I. Eighteen percent of adolescents stopped using marijuana after six years. Results suggest neighborhood context affects overall use level, whereas neighborhood context and friends were critical to cessation vs. continuation of use. Decrease in use were more likely among adolescents in disadvantaged or less cohesive neighborhoods, or who moved between waves. Non-use after one year was m...
Adolescents often befriend peers who are similar to themselves on a range of demographic, behavio... more Adolescents often befriend peers who are similar to themselves on a range of demographic, behavioral, and social characteristics, including substance use. Similarities in lifetime history of marijuana use have even been found to predict adolescent friendships, and we examine whether this finding is explained by youth's selection of friends who are similar on a range of more proximate, observable characteristics that are risk factors for marijuana use. Using two waves of individual and social network data from two high schools that participated in Add Health (N = 1,612; 52.7 % male), we apply longitudinal models for social networks to test whether or not several observable risky attributes (psychological, behavioral, and social) predict adolescent friendship choices, and if these preferences explain friend's similarities on lifetime marijuana use. Findings show that similarities on several risk factors predict friendship choices, however controlling for this, the preference t...
With marijuana use increasing among American adolescents, better understanding of the factors ass... more With marijuana use increasing among American adolescents, better understanding of the factors associated with decreasing use and quitting can help inform cessation efforts. This study evaluates a range of neighborhood, family, peer network, and individual factors as predictors of marijuana use, change, and non-use over one year, and cessation over six years. Data come from adolescents in Waves I and II of the National Longitudinal Study of Adolescent Health (N=458, one-year sample), or Waves I and III (N=358, six-year sample), and reported using marijuana at least four times in the past month at Wave I. Eighteen percent of adolescents stopped using marijuana after six years. Results suggest neighborhood context affects overall use level, whereas neighborhood context and friends were critical to cessation vs. continuation of use. Decrease in use were more likely among adolescents in disadvantaged or less cohesive neighborhoods, or who moved between waves. Non-use after one year was more likely among adolescents who did not move, had fewer marijuana-using friends, and did not exclusively have outside-of-school friends. Cessation at six years was more likely among adolescents in less disadvantaged and more cohesive neighborhoods, and for those with within-school friends. Results highlight the importance of both objective and subjective neighborhood characteristics, as well as peer networks, on adolescent marijuana use. Factors associated with decreases in use appear distinct from those that predict quitting, suggesting that continuation vs. cessation is linked to peers as well as neighborhood context. Relocated and isolated individuals may face challenges with cessation.
This longitudinal study examines individual differences in the tendency to initiate (N = 4,612) a... more This longitudinal study examines individual differences in the tendency to initiate (N = 4,612) and escalate (N = 2,837) smoking when adolescents gain a best friend who smokes. Potential moderating factors include self-esteem, depression, problem behavior, school and family bonds, and household access to cigarettes. In addition to acquiring a smoking best friend, initiation was predicted by trouble at school, household access, poorer grades and delinquency, whereas escalation was predicted by depressive symptoms. There was little evidence that the examined individual difference factors moderate the association between gaining a smoking best friend and increased adolescent smoking. Results point to the challenges of identifying factors that may lead adolescents to be more or less susceptible to the influence of pro-smoking friends.
Friends are thought to influence adolescent drug use. However, few studies have examined the role... more Friends are thought to influence adolescent drug use. However, few studies have examined the role of drugs in friendship selection, which is necessary to draw sound conclusions about influence. This study applied statistical models for social networks to test the contribution of selection and influence to associations in marijuana use among friends in two large high schools (N = 1,612; M age = 16.4). There was evidence for friend selection based on similar lifetime and current marijuana use at both schools, but friends were found to influence the initiation and frequency of adolescent marijuana use in just one of these schools. There was minimal evidence that peer effects were moderated by personal, school, or family risk factors.
We evaluated the effects of a culturally adapted evidence-based HIV prevention intervention (Mpow... more We evaluated the effects of a culturally adapted evidence-based HIV prevention intervention (Mpowerment), named “Tayf”, on condom use and HIV testing among young men who have sex with men (YMSM) in Beirut. A 2-year implementation of Tayf was carried out independently and in parallel with a research cohort of 226 YMSM who were surveyed at baseline and months 6, 12, 18 and 24 after Tayf initiation. Primary outcomes were (1) any condomless anal sex with HIV-positive or unknown status partners in the past 3 months, and (2) HIV testing in the past six months. Hierarchical logistic regression models examined the association of Tayf participation with the outcomes averaged across all assessments, and the moderating effect of Tayf participation on change in the outcomes over the follow-up period. A total of 331 YMSM attended at least one event, including 33% of the cohort. Tayf participation was associated with a higher rate of any condomless sex with HIV-positive or unknown status partners...
In 2012, our research with young men who have sex with men (YMSM) in Beirut showed high rates of ... more In 2012, our research with young men who have sex with men (YMSM) in Beirut showed high rates of recent condomless anal sex and low rates of recent HIV testing. In 2017, we collected data from YMSM to assess for temporal changes and sociodemographic correlates. Propensity score weighting was used to eliminate any sociodemographic differences between the 2012 ( n = 164) and 2017 ( n = 226) samples of YMSM (age 18–29) recruited with long-chain peer referral sampling. Regression analysis was used to examine sociodemographic correlates of recent condomless anal sex and HIV testing using the 2017 sample, and whether these behaviors differed between the samples. Compared to the 2012 sample, the 2017 sample was about half as likely to report any condomless anal sex in the past 3 months with partners whose HIV status was positive or unknown (14% vs. 23%; OR [95%CI] 0.56 [0.32, 0.98]), and nearly 2.5 times as likely to report HIV testing in the past 6 months (48% vs. 27%; OR [95%CI] 2.44 [1.46, 4.10]). In the 2017 sample, any recent condomless anal sex with partners whose HIV status was positive or unknown was associated with employment and Christian religious affiliation. Low income was the sole correlate of having recently tested for HIV. These findings suggest a temporal trend toward increased HIV protective behaviors among YMSM in Beirut over the past 5 years. Further inroads could be secured if HIV prevention programming targeted economic influences.
Bullying and homophobic teasing behaviors affect the lives of many school aged children, often co... more Bullying and homophobic teasing behaviors affect the lives of many school aged children, often co-occur, and tend to peak in middle school. While bullying and homophobic teasing behaviors are known to be peer group phenomena, studies typically examine the associations at the individual or school levels. An examination of these behaviors at the peer group level can aid in our understanding of the formation and maintenance of peer groups that engage in these forms of aggressive behavior (selection), and the extent to which friends and the peer group impact individual rates of these aggressive behaviors (influence). In this longitudinal study, we assess the co-evolution of friendship networks, bullying perpetration, and homophobic teasing among middle school students (n = 190) using a Stochastic Actor-Based Model (SABM) for longitudinal networks. Data were collected from 6-8th-grade students (Baseline age 12-15; 53% Female; 47% Male) across three waves of data. The sample was diverse w...
Journal of acquired immune deficiency syndromes (1999), Jan 7, 2018
and SettingBlack men who have sex with men (MSM) in the United States (U.S.) have disproportionat... more and SettingBlack men who have sex with men (MSM) in the United States (U.S.) have disproportionately high HIV infection rates. Social networks have been shown to influence HIV risk behavior; however, little is known about whether they affect the risk of HIV seroconversion. This study uses data from the BROTHERS (HPTN 061) study to test whether contextual factors related to social networks are associated with HIV seroconversion among black MSM.MethodsWe analyzed data from the BROTHERS study (2009-2011), which examined a multi-component intervention for black MSM in 6 U.S. cities. We ran a series of Cox regression analyses to examine associations between time-dependent measures of network support (personal/emotional, financial, medical, and social participation) and time to HIV seroconversion. We ran unadjusted models followed by models adjusted for participant age at enrollment and study location.ResultsA total of 1000 black MSM tested HIV negative at baseline and were followed at 6-...
To understand the process of practice transformation by identifying pathways for attaining patien... more To understand the process of practice transformation by identifying pathways for attaining patient-centered medical home (PCMH) recognition. The CMS Federally Qualified Health Center (FQHC) Advanced Primary Care Practice Demonstration was designed to help FQHCs achieve NCQA Level 3 PCMH recognition and improve patient outcomes. We used a stratified random sample of 20 (out of 503) participating sites for this analysis. We developed a conceptual model of structural, cultural, and implementation factors affecting PCMH transformation based on literature and initial qualitative interview themes. We then used conventional cross-case analysis, followed by qualitative comparative analysis (QCA), a cross-case method based on Boolean logic algorithms, to systematically identify pathways (i.e., combinations of factors) associated with attaining-or not attaining-Level 3 recognition. Site-level indicators were derived from semistructured interviews with site leaders at two points in time (mid- ...
The Journal of adolescent health : official publication of the Society for Adolescent Medicine, Jan 4, 2016
Homophobic victimization, and specifically name-calling, has been associated with greater psychol... more Homophobic victimization, and specifically name-calling, has been associated with greater psychological distress and alcohol use in adolescents. This longitudinal study examines whether sexual orientation moderates these associations and also differentiates between the effects of name-calling from friends and nonfriends. Results are based on 1,325 students from three Midwestern high schools who completed in-school surveys in 2012 and 2013. Linear regression analysis was used to examine the associations among homophobic name-calling victimization and changes in anxiety symptoms, depressive symptoms, and alcohol use one year later, controlling for other forms of victimization and demographics. Homophobic name-calling victimization by friends was not associated with changes in psychological distress or alcohol use among either students who self-identified as heterosexual or those who self-identified as lesbian, gay, or bisexual (LGB). In contrast, homophobic name-calling by nonfriends ...
With marijuana use increasing among American adolescents, better understanding of the factors ass... more With marijuana use increasing among American adolescents, better understanding of the factors associated with decreasing use and quitting can help inform cessation efforts. This study evaluates a range of neighborhood, family, peer network, and individual factors as predictors of marijuana use, change, and non-use over one year, and cessation over six years. Data come from adolescents in Waves I and II of the National Longitudinal Study of Adolescent Health (N=458, one-year sample), or Waves I and III (N=358, six-year sample), and reported using marijuana at least four times in the past month at Wave I. Eighteen percent of adolescents stopped using marijuana after six years. Results suggest neighborhood context affects overall use level, whereas neighborhood context and friends were critical to cessation vs. continuation of use. Decrease in use were more likely among adolescents in disadvantaged or less cohesive neighborhoods, or who moved between waves. Non-use after one year was m...
Adolescents often befriend peers who are similar to themselves on a range of demographic, behavio... more Adolescents often befriend peers who are similar to themselves on a range of demographic, behavioral, and social characteristics, including substance use. Similarities in lifetime history of marijuana use have even been found to predict adolescent friendships, and we examine whether this finding is explained by youth's selection of friends who are similar on a range of more proximate, observable characteristics that are risk factors for marijuana use. Using two waves of individual and social network data from two high schools that participated in Add Health (N = 1,612; 52.7 % male), we apply longitudinal models for social networks to test whether or not several observable risky attributes (psychological, behavioral, and social) predict adolescent friendship choices, and if these preferences explain friend's similarities on lifetime marijuana use. Findings show that similarities on several risk factors predict friendship choices, however controlling for this, the preference t...
With marijuana use increasing among American adolescents, better understanding of the factors ass... more With marijuana use increasing among American adolescents, better understanding of the factors associated with decreasing use and quitting can help inform cessation efforts. This study evaluates a range of neighborhood, family, peer network, and individual factors as predictors of marijuana use, change, and non-use over one year, and cessation over six years. Data come from adolescents in Waves I and II of the National Longitudinal Study of Adolescent Health (N=458, one-year sample), or Waves I and III (N=358, six-year sample), and reported using marijuana at least four times in the past month at Wave I. Eighteen percent of adolescents stopped using marijuana after six years. Results suggest neighborhood context affects overall use level, whereas neighborhood context and friends were critical to cessation vs. continuation of use. Decrease in use were more likely among adolescents in disadvantaged or less cohesive neighborhoods, or who moved between waves. Non-use after one year was more likely among adolescents who did not move, had fewer marijuana-using friends, and did not exclusively have outside-of-school friends. Cessation at six years was more likely among adolescents in less disadvantaged and more cohesive neighborhoods, and for those with within-school friends. Results highlight the importance of both objective and subjective neighborhood characteristics, as well as peer networks, on adolescent marijuana use. Factors associated with decreases in use appear distinct from those that predict quitting, suggesting that continuation vs. cessation is linked to peers as well as neighborhood context. Relocated and isolated individuals may face challenges with cessation.
This longitudinal study examines individual differences in the tendency to initiate (N = 4,612) a... more This longitudinal study examines individual differences in the tendency to initiate (N = 4,612) and escalate (N = 2,837) smoking when adolescents gain a best friend who smokes. Potential moderating factors include self-esteem, depression, problem behavior, school and family bonds, and household access to cigarettes. In addition to acquiring a smoking best friend, initiation was predicted by trouble at school, household access, poorer grades and delinquency, whereas escalation was predicted by depressive symptoms. There was little evidence that the examined individual difference factors moderate the association between gaining a smoking best friend and increased adolescent smoking. Results point to the challenges of identifying factors that may lead adolescents to be more or less susceptible to the influence of pro-smoking friends.
Friends are thought to influence adolescent drug use. However, few studies have examined the role... more Friends are thought to influence adolescent drug use. However, few studies have examined the role of drugs in friendship selection, which is necessary to draw sound conclusions about influence. This study applied statistical models for social networks to test the contribution of selection and influence to associations in marijuana use among friends in two large high schools (N = 1,612; M age = 16.4). There was evidence for friend selection based on similar lifetime and current marijuana use at both schools, but friends were found to influence the initiation and frequency of adolescent marijuana use in just one of these schools. There was minimal evidence that peer effects were moderated by personal, school, or family risk factors.
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Papers by Harold Green