Digital, Crowdsourced, Multilevel Intervention to Promote HIV Testing Among Men Who Have Sex With Men: Cluster Randomized Controlled Trial.

BACKGROUND: Despite great efforts in HIV prevention worldwide, HIV testing uptake among men who have sex with men (MSM) remains suboptimal. The effectiveness of digital, crowdsourced, multilevel interventions in improving HIV testing is still unclear. OBJECTIVE: The aim of this study was to evaluate the effect of a digital, crowdsourced, multilevel intervention in improving HIV testing uptake among MSM in China. METHODS: We conducted a 2-arm cluster randomized controlled trial among MSM in 11 cities in Shandong province, China, from August 2019 to April 2020. Participants were men who were HIV seronegative or had unknown serum status, had anal sex with a man in the past 12 months, and had not been tested for HIV in the past 3 months. Participants were recruited through a gay dating app and community-based organizations from preselected cities; these cities were matched into 5 blocks (2 clusters per block) and further randomly assigned (1:1) to receive a digital, crowdsourced, multilevel intervention (intervention arm) or routine intervention (control arm). The digital multilevel intervention was developed through crowdsourced open calls tailored for MSM, consisting of digital intervention images and videos, the strategy of providing HIV self-testing services through digital tools, and peer-moderated discussion within WeChat groups. The primary outcome was self-reported HIV testing uptake in the previous 3 months. An intention-to-treat approach was used to examine the cluster-level effect of the intervention in the 12-month study period using generalized linear mixed models and the individual-level effect using linear mixed models. RESULTS: A total of 935 MSM were enrolled (404 intervention participants and 531 controls); 751 participants (80.3%) completed at least one follow-up survey. Most participants were younger than 30 years (n=601, 64.3%), single (n=681, 72.8%), had a college degree or higher (n=629, 67.3%), and had an HIV testing history (n=785, 84%). Overall, the proportion of testing for HIV in the past 3 months at the 3-, 6-, 9-, and 12-month follow-ups was higher in the intervention arm (139/279, 49.8%; 148/266, 55.6%; 189/263, 71.9%; and 171/266, 64.3%, respectively) than the control arm (183/418, 43.8%; 178/408, 43.6%; 206/403, 51.1%; and 182/397, 48.4%, respectively), with statistically significant differences at the 6-, 9-, and 12-month follow-ups. At the cluster level, the proportion of participants who had tested for HIV increased 11.62% (95% CI 0.74%-22.5%; P=.04) with the intervention. At the individual level, participants in the intervention arm had 69% higher odds for testing for HIV in the past 3 months compared with control participants, but the result was not statistically significant (risk ratio 1.69, 95% CI 0.87-3.27; P=.11). CONCLUSIONS: The intervention effectively improved HIV testing uptake among Chinese MSM. Our findings highlight that digital, crowdsourced, multilevel interventions should be made more widely available for HIV prevention and other public health issues. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900024350; http://www.chictr.org.cn/showproj.aspx?proj=36718. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s13063-020-04860-8.

Analysis on epidemiological characters and HIV care continuum of HIV-infected students: a retrospective cohort study in Shandong province, China.

BACKGROUD: The proportion of HIV-infected students in China showed an increasing trend. This study aimed to identify the epidemiological characteristics and the HIV care continuum for HIV-infected students in Shandong Province, China. METHODS: Case report and follow-up data of HIV-infected students were obtained from the National HIV/AIDS comprehensive response information management system. Logistic regression analyses were used to analyze the associating factors of HIV-infected students accepting CD4 + T cells (CD4) test and antiviral therapy (ART) in 30 days, and ArcGIS software was used for the spatial anlysis. RESULTS: From 2017 to 2019, 403 HIV-infected students were reported in Shandong Province. The majority of them were male (99.5%) and transmitted through homosexual sexual activity(92.1%). Most of them lived in Jinan city and Qingdao city. 68.5% (276 cases) accepted CD4 test in 30 days, and 48.6% (196 cases) started ART in 30 days. The heterosexual transmitted cases (AOR = 0.458, 95%CI: 0.210-0.998), patients accepting HIV care in western area (AOR = 0.266,95%CI: 0.147-0.481) were less likely to test CD4 within 30 days; patients aged 23-25 (AOR = 2.316, 95%CI: 1.009-5.316) and patients who had tested CD4 within 30 days (AOR = 4.377; 95%CI: 2.572-7.447) prefered to receive ART within 30 days; patients accepted HIV care in central area (AOR = 0.407; 95%CI: 0.251-0.657) and western area (AOR = 0.508; 95%CI: 0.261-0.989) and patients diagnosed by voluntary blood donation (AOR = 0.352; 95%CI: 0.144-0.864) were less willing to receive ART in 30 days. CONCLUSIONS: The HIV care continuum of HIV-infected students in Shandong Province still needed strenghthing. More health education and case management should be done for cases transmitted through heterosexual behavior, accepted HIV care in central and western area, and diagnosed by voluntary blood donation.

The care status and factors affecting antiretroviral therapy timing for people living with HIV: a retrospective cohort study in Shandong Province, China.

This study described the care status of People Living with HIV (PLWH) including antiretroviral therapy (ART) and viral suppression from 2018 to 2020. We recognized that immediate ART was associated with improved viral suppression. Therefore, we also aimed to explore the factors affecting the early initiation of ART. We initiated a retrospective cohort study to evaluate the care status of people living with HIV in Shandong Province. From 2018 to 2020, patients infected by homosexual transmission in particular had a higher ART rate (78.82%, 79.69%, and 87.72%, respectively). Of PLWH who received ART, 79.57%, 77.63%, and 67.71% achieved viral suppression, respectively. However, COVID-19 may affect the rate of ART and viral suppression, which we need to explore in our research. From 2018 to 2020, the proportion of immediate antiretroviral therapy within 30 days of diagnosis increased from 48.12% to 65.42%. Multivariate logistic regression demonstrated that patients with junior college degree or above (OR, 1.39 [95%CI, 1.12-1.73]) and key population or medical institutions (OR, 3.62 [95%CI, 2.18-6.16]; OR, 3.88 [95%CI, 2.33-6.59]) were substantially likely to receive ART immediately, while patients outside the province (OR, 0.60 [95%CI, 0.50-0.73]) were less likely to receive ART immediately.

Immunogenicity and safety of a live attenuated varicella vaccine co-administered with inactive hepatitis A vaccine: A phase 4, single-center, randomized, controlled trial.

Co-administration of vaccines can facilitate the introduction of new vaccines in immunization schedules. This study aimed to evaluate the immunogenicity and safety of co-administration with live attenuated varicella vaccine (VarV) and inactivated hepatitis A vaccine (HepA) among children aged 12 ~ 15 months. In this phase 4 clinical trial, 450 children were randomized with a ratio of 1:1 to receive VarV and Hep A simultaneously (Group A) or separately (Group B). The primary endpoints were the seroconversion rate of anti-varicella-zoster virus (VZV) antibodies 42 days after vaccination of VarV and the seroconversion rate of anti-Hepatitis A virus (HAV) antibodies 30 days after two-dose vaccination of HepA. After full immunization, the seroconversion rates of anti-VZV antibodies were 91.79% in Group A and 92.15% in Group B; the geometric mean titers (GMTs) were 11.80 and 12.19, respectively. The seroconversion rates of anti-HAV antibodies were 99.48% in Group A and 100.0% in Group B; the geometric mean concentrations (GMCs) reached 9499.11 and 9528.36 mIU/ml, respectively. The lower limits of the 95% CI for the seroconversion difference of anti-VZV antibodies and anti-HAV antibodies were -5.86% and -2.90%, which greater than the predefined non-inferiority margin (-10%). The incidence rate of adverse reactions in Group A was lower than Group B (9.33% vs 16.22%), and only one serious adverse event was reported in Group B, which was unrelated to the study vaccine. In conclusion, the co-administration of VarV with HepA has non-inferior immunogenicity and safety profiles were quite comparable with the separate administration of both vaccines.Trial registration number: NCT05526820 (ClinicalTrials.gov).

HIV Status Disclosure and Associated Characteristics Among HIV-Positive MSM Receiving Antiretroviral Therapy in Jinan, China.

Disclosure of HIV status offers potential benefits to individuals and is also good for public health. Limited studies have been conducted to gain insight into the current situation and associated factors of HIV disclosure among HIV-positive Chinese men who have sex with men (MSM) in the era of "treat all." We carried out a cross-sectional study among MSM receiving antiretroviral therapy from October 2020 to January 2021 at a hospital in Jinan, China. We used univariate and multivariable logistic regression to examine the factors associated with general disclosure and disclosure to family, friends, and sexual partners. Of the 585 participants recruited, 62.2% reported HIV disclosure, among which 25.3% had disclosed their status to family members, 25.3% had disclosed it to friends, and 28.4% had disclosed it to partners. The findings suggest that HIV disclosure is more likely to occur among individuals who are younger, married/cohabiting, and who self-identify as homosexual/bisexual. Participants with higher education levels or personal monthly incomes are less likely to disclose their HIV status. Furthermore, related factors of disclosure vary across the types of disclosure targets. Given the positive outcomes of disclosure, interventions and implementation research to facilitate it are urgently needed for MSM.

A qualitative study on high risk behaviors of HIV/AIDS among young adult males in Shandong Province / 中国学校卫生

Objective@#To identify high risk behaviors and infection related factors among young adult males diagnosed with HIV/AIDS in Shandong Province, to provide evidence for targeted AIDS prevention and control strategies.@*Methods@#By using convient sampling method, an face to face in depth interview on HIV related behaviors was conducted among young adult males newly diagnosed with HIV/AIDS in Shandong Province in July 2021.@*Results@#A total of 31 young adult males diagnosed with HIV/AIDS were interviewed. All were male and infected through homosexuality behavior. Average age was (20.6±1.8) years. Totally 90.3% (28/31) were enrolled in tertiary education at the time of diagnosis. The findings revealed that 93.5% (29/31) of participants got infection due to unprotected homosexual behavior with the temporary partner whose HIV infection status was unknown, and 86.2% (25/29) got in touch with these temporary partner by social software. The awareness rate of knowledge about AIDS among all the participants was 100%, however, 83.9% (26/31) reported occasion condom usage while having homosexual behavior, and 16.1% (5/31) never did. Totally 74.2% (23/31) of the young adult males diagnosed with HIV/AIDS had a history of HIV testing before diagnosis.@*Conclusion@#The primary high risk behavior of HIV infection in young adult students are unawareness of HIV infection status for temporary sexual partner and the separation of knowing and doing. A targeted strategy should be developed to control the spread of HIV in young adult students.

HIV infection disclosure, treatment self-efficacy and quality of life in HIV-infected MSM receiving antiretroviral therapy.

BACKGROUND: Research on the relationship between disclosure of HIV status to male sexual partners (HIV disclosure) and quality of life (QOL) revealed complex and even contradictory results. The impact of HIV disclosure on various domains of QOL and the mediation effect between them are unclear. The purposes of this study were to explore the impact of HIV disclosure on QOL among men who have sex with men (MSM), and whether HIV treatment self-efficacy mediated these relationships. METHODS: The data came from a baseline survey on the design of a randomized control trial conducted in Shandong, China. A total of 579 MSM patients were included. SPSS 24.0 was used to conduct independent samples t test, one-way analysis of variance and nonparametric tests and the PROCESS macro was used to conduct mediation analysis. RESULTS: Among 579 participants, 16.06% disclosed their HIV infection status to their male sexual partners. The effect of HIV disclosure on QOL was mediated by treatment self-efficacy. Self-efficacy played partial mediating role in social relationships, meaning that HIV disclosure had both direct and indirect effects on this factor. In the overall QOL and domains of physical, psychological, independence, and environment, HIV disclosure had an indirect effect only through self-efficacy and no significant effect on the spirituality domain. CONCLUSIONS: The results emphasize the importance of HIV disclosure and self-efficacy on the QOL of MSM patients and suggest that health care providers should assist MSM patients in deciding whether to disclose their HIV status during daily medical services.

Impact of antiretroviral therapy (ART) duration on ART adherence among men who have sex with men (MSM) living with HIV in Jinan of China.

BACKGROUND: Consistent and complete adherence is considered an essential requirement for patients on antiretroviral therapy (ART). This study aimed to evaluate the impact of ART duration on ART adherence, identify the trend of complete adherence, and compare the factors associated with ART adherence between short-term and long-term ART group among men who have sex with men (MSM) living with HIV in Jinan of China. METHODS: MSM living with HIV aged 18 or above and currently on ART were recruited from October to December 2020 using convenience sampling. Univariate and multivariable logistic regressions were used to evaluate the impact of ART duration on adherence and compare factors associated with ART adherence between subgroups. The Mann-Kendall test was used to identify the trend of complete adherence. RESULTS: A total of 585 participants were included in analysis, consisting of 352 on short-term ART (ART initiation ≤ 3 years) and 233 on long-term ART (ART initiation > 3 years). Significant difference of complete ART adherence between short-term and long-term ART group was detected (79.8% vs. 69.1%, P = 0.003). Multivariable analysis showed that men with longer ART duration were less likely to report complete ART adherence (AOR = 0.88, 95% CI 0.81-0.95). A descending trend of complete adherence was identified (Z = 1.787, P = 0.037). Alcohol use and lack of medication reminders were barriers to complete adherence for both of the subgroups. CONCLUSIONS: Sustained efforts to encourage maintaining adherence for a lifetime are necessary, especially for those on long-term ART. Future interventions should be tailored to subgroups with different ART duration and individuals with specific characteristics.

A differentiated digital intervention to improve antiretroviral therapy adherence among men who have sex with men living with HIV in China: a randomized controlled trial.

BACKGROUND: Antiretroviral therapy (ART) adherence is still suboptimal among some key populations, highlighting the need for innovative tailored strategies. This randomized controlled trial (RCT) aimed to evaluate the effect of a differentiated digital intervention on ART adherence among men who have sex with men (MSM) living with HIV in China. METHODS: The two-armed parallel RCT was conducted at one HIV clinic in Jinan of China from October 19, 2020, to June 31, 2021. Men were referred by health providers to join the study and then choose one of three digital strategies-text message, only instant message, or instant message plus social media. They were assigned in a 1:1 ratio to the intervention arm or control arm using block randomization, and inside each arm, there were three groups depending on the type of delivering the message. The groups were divided according to participants' preferred digital strategies. The intervention arm received ART medication messages, medication reminders, peer education, and involved in online discussion. The control arm received messages on health behavior and nutrition. The primary outcome was self-reported optimal ART adherence, defined as not missing any doses and not having any delayed doses within a one-month period. Secondary outcomes included CD4 T cell counts, viral suppression, HIV treatment adherence self-efficacy, and quality of life. Intention-to-treat analysis with generalized linear mixed models was used to evaluate the intervention's effect. RESULTS: A total of 576 participants were enrolled, including 288 participants assigned in the intervention arm and 288 assigned in the control arm. Most were ≤ 40 years old (79.9%) and initiated ART ≤ 3 years (60.4%). After intervention, the proportion of participants achieving optimal ART adherence in the intervention arm was higher than in the control arm (82.9% vs 71.1%). The differentiated digital intervention significantly improved ART adherence (RR = 1.74, 95%CI 1.21-2.50). Subgroup analysis showed one-to-one instant message-based intervention significantly improved ART adherence (RR = 2.40, 95% CI 1.39-4.17). CONCLUSIONS: The differentiated digital intervention improved ART adherence among MSM living with HIV in China, which could be integrated into people living with HIV (PLWH) management and further promoted in areas where PLWH can access text messaging and instant messaging services. TRIAL REGISTRATION: ChiCTR2000041282. Retrospectively registered on 23 December 2020.

Corrigendum: Genomic Investigation Reveals a Community Typhoid Outbreak Caused by Contaminated Drinking Water in China, 2016.

[This corrects the article DOI: 10.3389/fmed.2022.753085.].

Genomic Investigation Reveals a Community Typhoid Outbreak Caused by Contaminated Drinking Water in China, 2016.

Typhoid fever is a life-threatening disease caused by Salmonella enterica serovar Typhi (S. Typhi) and remains a significant public health burden in developing countries. In China, typhoid fever is endemic with a limited number of reported outbreaks. Recently, Chinese local Center for Disease Prevention and Control is starting to apply whole genome sequencing for tracking the source of outbreak isolates. In this study, we conducted a retrospective investigation into a community outbreak of typhoid fever in Lanling, China, in 2016. A total of 26 S. Typhi isolates were recovered from the drinking water (n = 1) and patients' blood (n = 24) and stool (n = 1). Phylogenetic analysis indicated the persistence of the outbreak isolates in drinking water for more than 3 months. The genomic comparison demonstrated a high similarity between the isolate from water and isolates from patients in their genomic content, virulence gene profiles, and antimicrobial resistance gene profile, indicating the S. Typhi isolate from drinking water was responsible for the examined outbreak. The result of pulsed-field gel electrophoresis (PFGE) revealed these isolates had identical PFGE pattern, indicating they are clonal variants. Additionally, phylogeographical analysis of global S. Typhi isolates suggested the outbreak isolates are evolutionarily linked to the isolates from the United Kingdom and Vietnam. Taken together, this study highlights the drinking water and international travel as critical control points of mitigating the outbreak, emphasizing the necessity of regular monitoring of this pathogen in China.

Lasting antibody and T cell responses to SARS-CoV-2 in COVID-19 patients three months after infection.

The dynamics, duration, and nature of immunity produced during SARS-CoV-2 infection are still unclear. Here, we longitudinally measured virus-neutralising antibody, specific antibodies against the spike (S) protein, receptor-binding domain (RBD), and the nucleoprotein (N) of SARS-CoV-2, as well as T cell responses, in 25 SARS-CoV-2-infected patients up to 121 days post-symptom onset (PSO). All patients seroconvert for IgG against N, S, or RBD, as well as IgM against RBD, and produce neutralising antibodies (NAb) by 14 days PSO, with the peak levels attained by 15-30 days PSO. Anti-SARS-CoV-2 IgG and NAb remain detectable and relatively stable 3-4 months PSO, whereas IgM antibody rapidly decay. Approximately 65% of patients have detectable SARS-CoV-2-specific CD4+ or CD8+ T cell responses 3-4 months PSO. Our results thus provide critical evidence that IgG, NAb, and T cell responses persist in the majority of patients for at least 3-4 months after infection.

Epidemiology of HIV/AIDS among students in Shandong Province from 2010 to 2019 / 中国学校卫生

Objective@#To analyze the epidemiological characteristics of HIV/AIDS infected students in Shandong Province, to provide a basis for the prevention and control of AIDS transmission in the student population.@*Methods@#All 863 HIV/AIDS students cases during 2010-2019 were collected in Shandong Province. Epidemiological characteristics was described and the trends in the 10 years since 2010 was analyzed.@*Results@#These 863 HIV/AIDS students were mainly transmitted through homosexual sex (763 cases, 88.41%), and the samples were mainly from voluntary consultation testing (433 cases, 50.17%). From 2010 to 2019, the proportion of student cases in the total number of cases showed an increasing trend ( χ 2 trend =30.21, P <0.01). Among them, the proportion of homosexual transmission cases increased year by year ( χ 2 trend =6.35, P =0.01), the proportion of cases aged 18-22 years increased year by year ( χ 2 trend =6.10, P =0.01), the proportion of cases with college degree or above increased year by year ( χ 2 trend =4.26, P =0.04). At present, voluntary consultation testing were the main source.There was no significant difference between the years of sample sources ( χ 2 trend =2.97, P =0.09).@*Conclusion@#The report number of students in Shandong Province are on the rise in recent years, especially those infected by same sex transmission, mainly with high education background, which calls for targeted strategies and intervention measures.

Digital crowdsourced intervention to promote HIV testing among MSM in China: study protocol for a cluster randomized controlled trial.

BACKGROUND: Men who have sex with men (MSM) are an important HIV key population in China. However, HIV testing rates among MSM remain suboptimal. Digital crowdsourced media interventions may be a useful tool to reach this marginalized population. We define digital crowdsourced media as using social media, mobile phone applications, Internet, or other digital approaches to disseminate messages developed from crowdsourcing contests. The proposed cluster randomized controlled trial (RCT) study aims to assess the effectiveness of a digital crowdsourced intervention to increase HIV testing uptake and decrease risky sexual behaviors among Chinese MSM. METHODS: A two-arm, cluster-randomized controlled trial will be implemented in eleven cities (ten clusters) in Shandong Province, China. Targeted study participants will be 250 MSM per arm and 50 participants per cluster. MSM who are 18 years old or above, live in the study city, have not been tested for HIV in the past 3 months, are not living with HIV or have never been tested for HIV, and are willing to provide informed consent will be enrolled. Participants will be recruited through banner advertisements on Blued, the largest gay dating app in China, and in-person at community-based organizations (CBOs). The intervention includes a series of crowdsourced intervention materials (24 images and four short videos about HIV testing and safe sexual behaviors) and HIV self-test services provided by the study team. The intervention was developed through a series of participatory crowdsourcing contests before this study. The self-test kits will be sent to the participants in the intervention group at the 2nd and 3rd follow-ups. Participants will be followed up quarterly during the 12-month period. The primary outcome will be self-reported HIV testing uptake at 12 months. Secondary outcomes will include changes in condomless sex, self-test efficacy, social network engagement, HIV testing social norms, and testing stigma. DISCUSSION: Innovative approaches to HIV testing among marginalized population are urgently needed. Through this cluster randomized controlled trial, we will evaluate the effectiveness of a digital crowdsourced intervention, improving HIV testing uptake among MSM and providing a resource in related public health fields. TRIAL REGISTRATION: ChiCTR1900024350 . Registered on 6 July 2019.

Nosocomial cross-infection of hypervirulent Listeria monocytogenes sequence type 87 in China.

BACKGROUND: To investigate the epidemiological and phenotypic characteristics and molecular relatedness of L. monocytogenes, which were cultured from the blood and cerebrospinal fluid (CSF) samples isolated from two neonates. METHODS: In the present case study, two infected neonates were interviewed and epidemiological investigation performed. The phenotypic characteristics and molecular relatedness of L. monocytogenes was characterized by serotyping, pulsed-field gel electrophoresis and whole-genome sequencing (WGS). RESULTS: The field investigation found that the two neonates were born in the same hospital (Hospital B) and admitted to the neonatal department through different channels within half an hour by different nurses, where they were weighed and placed in different but adjacent incubators. Then they were cared for by the same group of nurses that evening. It is worth noting that there was no record of sanitation of the neonatal incubator of neonate-1. The serotype of the two isolated L. monocytogenes were 1/2b, with an indistinguishable pulsotypes and were sequence type (ST) 87. WGS showed that there were no core SNP differences identified. In order to explore the genomic traits associated with L. monocytogenes virulence genes, we identified the Listeria pathogenicity island 4 and found that the genome was devoid of any stress islands. There are no positive results from the environmental samples. Considering the genomic data together with epidemiological evidence and clinical symptoms, insufficient surface cleaning along with the nursing staff caring for these neonates was considered as cross-infection factors. CONCLUSIONS: To our knowledge, this is the first report of a nosocomial cross-infection of L. monocytogenes ST87 between two neonates, which carries the recently identified gene cluster expressing the cellobiose-family phosphotransferase system (PTS-LIPI-4) between two neonates. The test results of environmental samples in the hospital indicate that strict sterilization and patient isolation measures cannot be emphasized enough in neonatal nursing.

Transmission Potential of Asymptomatic and Paucisymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infections: A 3-Family Cluster Study in China.

Data concerning the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in asymptomatic and paucisymptomatic patients are lacking. We report a 3-family cluster of infections involving asymptomatic and paucisymptomatic transmission. Eight of 15 (53%) members from 3 families were confirmed with SARS-CoV-2 infection. Of 8 patients, 3 were asymptomatic and 1 was paucisymptomatic. An asymptomatic mother transmitted the virus to her son, and a paucisymptomatic father transmitted the virus to his 3-month-old daughter. SARS-CoV-2 was detected in the environment of 1 household. The complete genomes of SARS-CoV-2 from the patients were > 99.9% identical and were clustered with other SARS-CoV-2 sequences reported from China and other countries.

Mediation Analysis of Peer Norms, Self-Efficacy, and Condom Use Among Chinese Men Who Have Sex with Men: A Parallel Process Latent Growth Curve Model.

The objective of this study was to examine direct and indirect relationships among peer norms, self-efficacy, and condom use among Chinese men who have sex with men (MSM). A longitudinal study determined the effectiveness of a condom use video promotion among Chinese MSM in 2015. In this analysis, 804 Chinese MSM were recruited at baseline and then followed at 3 weeks and 3 months after the intervention. Parallel process latent growth curve modeling (LGM) with multiple indicators and bootstrapping was conducted using Mplus 7.4. The LGM model fit indexes were good with RMSEA = 0.046, 90% CI (0.044, 0.048), CFI = 0.956, TLI = 0.955. Our results showed that the initial measure of peer norms affected the initial measure of condom use indirectly through the initial measure of self-efficacy (αß = 0.414, 95% CI 0.260-0.759). The rate of change in peer norms over time also significantly affected the rate of change in condom use through the rate of change in self-efficacy (αß = 0.101, 95% CI 0.014-0.262). Self-efficacy mediated the association between peer norms and condom use, indicating a strong potential of causal relationship between peer norms and self-efficacy among Chinese MSM.

Growth Trajectories of Peer Norms, Self-efficacy and Condom Use Behavior Among Sexually Active Chinese Men Who Have Sex with Men: Latent Class Analysis and Growth Mixture Modeling.

Data from a randomized controlled trial in 2015 were used to estimate the growth trajectories of peer norms, self-efficacy, and condom use behavior, and to identify associated sociodemographic and behavioral factors among a sample of 804 Chinese men who have sex with men (MSM). Latent class analysis and growth mixture modeling were conducted using Mplus. Two growth trajectories were estimated for each outcome variable with good model fit. The growth trajectories of peer norms were related to age (ß = - 0.066, p < 0.05). The growth trajectories of self-efficacy were related to age (ß = 0.057, p < 0.01) and using a condom during first sexual encounter with another man (ß = 0.777, p < 0.001). The growth trajectories of condom use behavior were related to income (ß = 0.366, p < 0.01) and having casual male partners (ß = - 1.016, p < 0.001). Predictors for the growth factors within each latent class were also estimated. For subsets of MSM who are older, richer, used a condom during their first sexual encounter with another man, and do not have a casual male partner, condom videos may not have sufficient efficacy and other interventions may be necessary.