Biomedical subjects

Juwon Song

Publications and source records attributed to Juwon Song.

3 recordsLinked to original sources

PubMed2005

The influence of partner type and risk status on the sexual behavior of young men who have sex with men living with HIV/AIDS.

OBJECTIVES: The influence of partner type and risk status on the unprotected sexual behavior of young men living with HIV (YMLH) who have sex with men is examined. METHODS: Sexual behavior and sexual partner characteristics of 217 YMLH recruited from adolescent care clinics in 4 AIDS epicenters (Los Angeles, San Francisco, New York, and Miami) were assessed. YMLH were categorized by sexual behavior pattern, and sexual partners were classified by type and risk status. Generalized linear modeling employing overdispersed Poisson distribution was used to analyze the effect of partner type and partner risk status on unprotected sex acts. RESULTS: Most YMLH (62%) reported multiple partners, 26% reported 1 sexual partner, and 12% reported abstinence in the past 3 months. Approximately 34% of polygamous and 28% of monogamous youth engaged in unprotected sex. Monogamous youth were most likely to have unprotected sex with HIV-positive partners. Polygamous youth were most likely to have unprotected sex with HIV-positive partners, irrespective of whether the partner was regular or casual. For polygamous YMLH, unprotected sex did not differ among single-time/new partners with different risk levels. CONCLUSIONS: Partner characteristics influence the condom use behavior of YMLH. YMLH make decisions regarding condom use based on perception of their partner's risk. Preventive interventions must include skills for acquiring accurate information about partner risk status and education regarding the health risks of unprotected sex with HIV seroconcordant partners.

Adolescent↗

PubMed2004

Imputation for incomplete high-dimensional multivariate normal data using a common factor model.

It is common in applied research to have large numbers of variables measured on a modest number of cases. Even with low rates of missingness on individual variables, such data sets can have a large number of incomplete cases. Here we present a new method for handling missing continuously scaled items in multivariate data, based on extracting common factors to reduce the number of covariance parameters to be estimated in a multivariate normal model. The technique is compared in several simulation settings to available-case analysis and to a multivariate normal model with a ridge prior. The method is also illustrated on a study with over 100 variables evaluating an emergency room intervention for adolescents who attempted suicide.

Humans↗

PubMed2003

Reductions in HIV risk among runaway youth.

Runaway youth are 6-12 times more likely to become infected with HIV than other youth. Using a quasi-experimental design, the efficacy of an HIV prevention program was evaluated over 2 years among 2 groups of runaways: (1) those at 2 shelters who received Street Smart, an intensive HIV intervention program, and (2) youth at 2 control shelters. Street Smart provided youth with access to health care and condoms and delivered a 10-session skill-focused prevention program based on social learning theory to youth. Prior to analysis of the intervention's outcomes, propensity scores were used to identify comparable subgroups of youth in the intervention (n = 101) and control conditions (n = 86). Compared to females in the control condition, females in the intervention condition significantly reduced their unprotected sexual acts at 2 years and alcohol use, marijuana use, and the number of drugs used over 12 months. Male adolescents in the intervention condition showed significant reductions in marijuana use over 6 months compared to control youth. Adolescent HIV prevention programs must proactively identify mechanisms for maintaining behavior change over the long-term, and innovative research designs are needed to allow examination of agency-level interventions.

Adolescent↗