Willingness to participate in AIDS vaccine trials among high-risk populations in northern Thailand

Strategies to improve recruitment to randomised trials

BACKGROUND

Recruiting participants to trials can be extremely difficult. Identifying strategies that improve trial recruitment would benefit both trialists and health research.

OBJECTIVES

To quantify the effects of strategies for improving recruitment of participants to randomised trials. A secondary objective is to assess the evidence for the effect of the research setting (e.g. primary care versus secondary care) on recruitment.

SEARCH METHODS

We searched the Cochrane Methodology Review Group Specialised Register (CMR) in the Cochrane Library (July 2012, searched 11 February 2015); MEDLINE and MEDLINE In Process (OVID) (1946 to 10 February 2015); Embase (OVID) (1996 to 2015 Week 06); Science Citation Index & Social Science Citation Index (ISI) (2009 to 11 February 2015) and ERIC (EBSCO) (2009 to 11 February 2015).

SELECTION CRITERIA

Randomised and quasi-randomised trials of methods to increase recruitment to randomised trials. This includes non-healthcare studies and studies recruiting to hypothetical trials. We excluded studies aiming to increase response rates to questionnaires or trial retention and those evaluating incentives and disincentives for clinicians to recruit participants.

DATA COLLECTION AND ANALYSIS

We extracted data on: the method evaluated; country in which the study was carried out; nature of the population; nature of the study setting; nature of the study to be recruited into; randomisation or quasi-randomisation method; and numbers and proportions in each intervention group. We used a risk difference to estimate the absolute improvement and the 95% confidence interval (CI) to describe the effect in individual trials. We assessed heterogeneity between trial results. We used GRADE to judge the certainty we had in the evidence coming from each comparison.

MAIN RESULTS

We identified 68 eligible trials (24 new to this update) with more than 74,000 participants. There were 63 studies involving interventions aimed directly at trial participants, while five evaluated interventions aimed at people recruiting participants. All studies were in health care.We found 72 comparisons, but just three are supported by high-certainty evidence according to GRADE.1. Open trials rather than blinded, placebo trials. The absolute improvement was 10% (95% CI 7% to 13%).2. Telephone reminders to people who do not respond to a postal invitation. The absolute improvement was 6% (95% CI 3% to 9%). This result applies to trials that have low underlying recruitment. We are less certain for trials that start out with moderately good recruitment (i.e. over 10%).3. Using a particular, bespoke, user-testing approach to develop participant information leaflets. This method involved spending a lot of time working with the target population for recruitment to decide on the content, format and appearance of the participant information leaflet. This made little or no difference to recruitment: absolute improvement was 1% (95% CI -1% to 3%).We had moderate-certainty evidence for eight other comparisons; our confidence was reduced for most of these because the results came from a single study. Three of the methods were changes to trial management, three were changes to how potential participants received information, one was aimed at recruiters, and the last was a test of financial incentives. All of these comparisons would benefit from other researchers replicating the evaluation. There were no evaluations in paediatric trials.We had much less confidence in the other 61 comparisons because the studies had design flaws, were single studies, had very uncertain results or were hypothetical (mock) trials rather than real ones.

AUTHORS' CONCLUSIONS

The literature on interventions to improve recruitment to trials has plenty of variety but little depth. Only 3 of 72 comparisons are supported by high-certainty evidence according to GRADE: having an open trial and using telephone reminders to non-responders to postal interventions both increase recruitment; a specialised way of developing participant information leaflets had little or no effect. The methodology research community should improve the evidence base by replicating evaluations of existing strategies, rather than developing and testing new ones.

Typologies of Altruistic and Financial Motivations for Research Participation

Questions arise concerning participants' motives in risky studies, such as HIV vaccine trials (HVTs). We interviewed in-depth 20 gay/bisexual men. Participants described both altruistic and nonaltruistic motives. Altruistic motivations emerged primarily, with nine typologies: (a) cultural, (b) community related, (c) familial, (d) religious, (e) professional, (f) political (e.g., HIV activism), (g) moral (e.g., making up for past wrongs), (h) existential (e.g., providing sense of meaning), and (i) other psychological (e.g., emotional gratification). Views of compensation varied: not a factor (55%), added incentive (25%), main motivator, but in conjunction with altruism (15%), and primary motivator (5%). HVT participants thus often have both altruistic and financial motives, and related typologies emerged. These findings have critical implications for studies on HIV, other conditions, and research ethics.

Community Members' Perceptions of Enablers and Inhibitors to Participation in HIV Vaccine Trials

We present the findings of a qualitative investigation into the factors that may enable or inhibit participation in a future HIV vaccine trial. Thirty-seven semi-structured interviews and two focus groups were conducted with trial site community members who had attended HIV vaccine education workshops conducted by the community involvement programme of the South African AIDS Vaccine Initiative (SAAVI). Our findings indicate that enablers and inhibitors to participation in HIV vaccine trials may. be further classified as either abstract or concrete. Each sub-theme was classified as an abstract inhibitor, abstract enabler, concrete inhibitor, or concrete enabler. Abstract inhibitors were fear of illness or death, lack of information about HIV/AIDS and HIV vaccines, and an HIV vaccine trial's association with HIV/AIDS. Abstract enablers were participants' reported sense of altruism and quality of life issues, such as protection from becoming infected with HIV. Concrete inhibitors were the monetary costs associated with participation, fear of being tested for HIV and receiving test results, negative reactions from family and community members, time delays between receiving trial participation information and actual enrolment, and a general mistrust of researchers. Concrete enablers were practicalities and convenience, financial rewards, a safe testing environment, positive family reactions to trial participation, the different levels of participation available to different members of the community, the salience of HIV in communities, positive community reactions to vaccine trials, and the presence of role models. In addition to these quadrants, the enablers and inhibitors have also been located within a contextual framework that includes the individual; family, community, and societal levels. Our research contributes to an understanding of the concerns of potential HIV vaccine trial participants within the South African context. Our findings illustrate the applicability of international research to proposed vaccine-trial activities in South Africa and should, therefore, inform the development and implementation of successful community preparedness activities.

Biomedical HIV prevention research and epidemic control in Thailand: two sides of the same coin

For a country with a moderate adult HIV prevalence of just over 1% in 2012, Thailand is widely perceived as having made some extraordinary contributions to the global management of the HIV/AIDS pandemic. It has been promoted as a model of effective HIV control and applauded for its leadership in providing access to antiretroviral treatment. Thailand has also received international recognition for its contribution to biomedical HIV prevention research, which is generally perceived as exceptional. In this paper, Thailand's global role model function as an example of effective HIV/AIDS control and high-quality biomedical HIV prevention research is re-evaluated against the background of currently available data and more recent insights. The results indicate that Thailand's initial response in raising the level of the political significance of HIV/AIDS was indeed extraordinary, which probably prevented a much larger epidemic from occurring. However, this response transpired in unusual extraconstitutional circumstances and its effectiveness declined once the country returned to political normalcy. Available data confirm the country's more than exceptional contribution to biomedical HIV prevention research. Thailand has made a huge contribution to the global management and control of the HIV/AIDS pandemic.

Characteristics of female sex workers in southern India willing and unwilling to participate in a placebo gel trial

Respondent-driven sampling was used to recruit female sex workers (FSWs) for a community survey conducted in southern India. After survey completion, participants were given a brochure describing a clinical trial that entailed daily use of a placebo vaginal gel for four months. This study assessed predictors of screening among survey respondents, predictors of enrollment among those eligible for the trial, and predictors of visit attendance and retention among those enrolled. FSWs who reported having symptoms of sexually transmitted infections (STI), engaging in sex work in the past month, and living in a subdistrict easily accessible by public transportation with a high concentration of FSWs, were more likely to screen. FSWs who had never been tested for HIV were more likely to enroll. This analysis suggests that the primary reason FSWs participated in the trial was a desire for health care-not other factors hypothesized to be important, e.g., HIV risk perception and poverty status.

Enhanced retention strategies and willingness to participate among hard-to-reach female sex workers in Barcelona for HIV prevention and vaccine trials

The potential for implementation of HIV vaccine trials in hard-to-reach female sex workers in an inner city area of Barcelona, Spain was assessed via a study of HIV risk, willingness to participate and the success of retention strategies. In 130 women, serological HIV status, behavioral risk exposures and willingness to participate in future HIV vaccine trials were recorded every six months using a confidential questionnaire. An enhanced retention (ER) strategy was compared with a control retention (CR) strategy comprising the recording of data on appointment cards. HIV seroincidence and retention rates were estimated. Retention rates after 6 and 12 mo of follow-up in the ER group were 76% and 69% respectively compared with 16% and 13% in the CR group. Among the ER group 97% were willing to participate in HIV vaccine trials at baseline and, after 12 mo of follow-up. Willingness was significantly associated with higher HIV risk exposure, and higher education level. Successfully retaining these cohorts over time in settings with a high HIV seroincidence rate is an ongoing challenge that will need to be addressed to ensure participation in future trials. Furthermore, as we have demonstrated, the fact that retaining hard-to-reach populations is difficult should not exclude this target population for HIV vaccine and prevention trials.

"Research participants want to feel they are better off than they were before research was introduced to them": engaging cameroonian rural plantation populations in HIV research

BACKGROUND

During a period of evolving international consensus on how to engage communities in research, facilitators and barriers to participation in HIV prevention research were explored in a rural plantation community in the coastal region of Cameroon.

METHODS

A formative rapid assessment using structured observations, focus group discussions (FGD), and key informant interviews (KIIs) was conducted with a purposive non-probabilistic sample of plantation workers and their household members. Eligibility criteria included living or working >1 year within the plantation community and age >18 years. Both rapid and in-depth techniques were used to complete thematic analysis.

RESULTS

Sixty-five persons participated in the study (6 FGDs and 12 KIIs). Participants viewed malaria and gastrointestinal conditions as more common health concerns than HIV. They identified three factors as contributing to HIV risk: concurrent sexual relationships, sex work, and infrequent condom use. Interviewees perceived that the community would participate in HIV research if it is designed to: (1) improve community welfare, (2) provide comprehensive health services and treatment for illnesses, (3) protect the personal information of participants, especially those who test positive for HIV, (4) provide participant incentives, (5) incorporate community input, and (6) minimize disruptions to "everyday life". Barriers to participation included: (1) fear of HIV testing, (2) mistrust of researchers given possible disrespect or intolerance of plantation community life and lack of concern for communication, (3) time commitment demands, (3) medical care and treatment that would be difficult or costly to access, and (4) life disruptions along with potential requirements for changes in behaviour (i.e., engage in or abstain from alcohol use and sex activities).

CONCLUSIONS

Consistent with UNAIDS guidelines for good participatory practice in HIV prevention research, study participants placed a high premium on researchers' politeness, trust, respect, communication, tolerance and empathy towards their community. Plantation community members viewed provision of comprehensive health services as an important community benefit likely to enhance HIV research participation.

"Once I begin to participate, people will run away from me": understanding stigma as a barrier to HIV vaccine research participation in Kenya

PURPOSE

Participation of volunteers in clinical research is essential to the development of effective HIV prevention methods, including an HIV vaccine. This study expands current knowledge of stigma and discrimination related to participation in HIV vaccine research in sub-Saharan Africa by exploring the perception of stigma and discrimination as a barrier to participation in HIV vaccine research in Kenya.

METHODS

Eighteen focus groups with a total of 133 participants and 82 individual interviews were conducted with a range of respondents at two centers in Nairobi, Kenya: a preventive AIDS vaccine trial center; and a preparatory clinical and epidemiological study center. Respondents included peer leaders, community advisory board members, former and current volunteers in clinical research, study staff, community leaders and community members. Data were analyzed using an iterative coding process.

RESULTS

Four prominent stigma-related barriers to participation emerged among all respondent groups, across both centers: (1) volunteers are often assumed by family and community members to be HIV positive because of their participation in vaccine research; (2) HIV-related stigma is perceived as pervasive and damaging in the communities where volunteers live, thus they fear consequent stigma if people believe them to be HIV positive; (3) potential volunteers fear being tested for HIV, a prerequisite for participation, because of possible disclosure of HIV status in communities with high perceived HIV-related stigma; and (4) volunteers must carefully manage information about their participation because of misperceptions and assumptions about vaccine research volunteers.

CONCLUSIONS

HIV-related stigma and discrimination influence people's decisions to join HIV-vaccine related research. Findings underscore a need for integration of stigma-reduction programming into education and outreach activities for volunteers, and the communities in which they live. This is particularly critical for trials recruiting individuals with higher HIV risk, who are often already highly stigmatized.

Barriers of enrolment in HIV vaccine trials: a review of HIV vaccine preparedness studies

Barriers to participation in an HIV vaccine trial have been examined in many HIV vaccine preparedness studies (VPS). These barriers can be understood in terms of the locus of the barrier (personal vs. social) and the nature of the barrier (risk vs. cost). Another type of barrier is perceived misconceptions. In this systematic review, we categorize barriers, and compare these barriers between the Organization for Economic Co-operation and Development (OECD) countries and the non-OECD countries. In the OECD countries, we retrieved 25 studies reporting personal risks (PR), 9 studies reporting social risks (SR), 10 studies reporting personal costs (PC), and 16 studies reporting misconceptions. In the non-OECD countries, we retrieved 27 studies reporting PR, 19 studies reporting SR, 18 studies reporting PC, 1 study reporting social costs (SC), and 13 studies reporting misconceptions. Important PR were "adverse effects" and "vaccine-induced seropositivity", "distrust of institutions", and "temptation to have unsafe sex" in men who have sex with men (MSM). "Discrimination" was a common SR. "Time commitment" was an important PC, and "family commitments" were a SC in one non-OECD country. "HIV infection from the vaccine" was a common misconception. Both the OECD and the non-OECD countries have similar barriers, and people's decisions to participate in a clinical trial involve multiple barriers. However, these barriers apply to hypothetical HIV vaccine trials, and barriers for actual vaccine trials need further assessment.

Motivators of enrolment in HIV vaccine trials: a review of HIV vaccine preparedness studies

HIV vaccine preparedness studies (VPS) are important precursors to HIV vaccine trials. As well, they contribute to an understanding of motivators and barriers for participation in hypothetical HIV vaccine trials. Motivators can take the form of altruism and a desire for social benefits. Perceived personal benefits, including psychological, personal, and financial well-being, may also motivate participation. The authors performed a systematic review of HIV VPS using the Cochrane Database for Systematic Reviews, Medline, PubMed, Embase, and Google Scholar. The authors independently searched the literature for individual HIV VPS that examined motivators of participation in a hypothetical HIV vaccine trial, using the same search strategy. As the denominators employed in the literature varied across studies, the denominators were standardized to the number of respondents per survey item, regardless of their willingness to participate (WTP) in an HIV vaccine trial. The authors retrieved eight studies on social benefits (i.e., altruism) and 11 studies on personal benefits conducted in the Organization for Economic Co-operation and Development (OECD) countries, as well as 19 studies on social benefits and 20 studies on personal benefits in the non-OECD countries. Various different forms of altruism were found to be the major motivators for participation in an HIV vaccine trial in both the OECD and the non-OECD countries. In a large number of studies, protection from HIV was cited as a personal motivator for participation in a hypothetical HIV vaccine trial in the OECD and the non-OECD countries. Knowledge of motivators can inform and target recruitment for HIV vaccine trials, although it must be remembered that hypothetical motivators may not always translate into motivators in an actual vaccine trial.

HIV infection awareness and willingness to participate in future HIV vaccine trials across different risk groups in Abuja, Nigeria

The purpose of this survey is to generate baseline data on the level of HIV infection awareness and willingness to participate (WTP) in hypothetical vaccine trials, ahead of any trial conduct in Nigeria. In a cross-sectional survey, 500 respondents were interviewed, including sex workers, male motorcycle taxi drivers, students, and the general public. About 153 (30.6%) of the respondents did not believe that correct and consistent use of condom can protect people from getting HIV, while about 66 (13.2%) respondents believed it is possible to get HIV by sharing meal with an infected person. Population groups considered at high risk for HIV were less aware of the disease, however, they were more willing to participate in HIV vaccine trials compared those at low risk of the disease. A total of 55% expressed WTP in a hypothetical vaccine trial after they were informed about it. Age, population group, and ethnicity were significantly associated with WTP.

Inhibitors and facilitators of willingness to participate (WTP) in an HIV vaccine trial: construction and initial validation of the Inhibitors and Facilitators of Willingness to Participate Scale (WPS) among women at risk for HIV infection

A psychometric scale assessing inhibitors and facilitators of willingness to participate (WTP) in an HIV vaccine trial has not yet been developed. This study aimed to construct and derive the exploratory factor structure of such a scale. The 35-item Inhibitors and Facilitators of Willingness to Participate Scale (WPS) was developed and administered to a convenience sample of 264 Black females between the ages of 16 and 49 years living in an urban-informal settlement near Cape Town. The subscales of the WPS demonstrated good internal consistency with Cronbach's alpha coefficients ranging between 0.69 and 0.82. A principal components exploratory factor analysis revealed the presence of five latent factors. The factors, which accounted for 45.93% of the variance in WTP, were (1) personal costs, (2) safety and convenience, (3) stigmatisation, (4) personal gains and (5) social approval and trust. Against the backdrop of the study limitations, these results provide initial support for the reliability and construct validity of the WPS among the most eligible trial participants in the Western Cape of South Africa.

Strategies to improve recruitment to randomised controlled trials

BACKGROUND

Recruiting participants to trials can be extremely difficult. Identifying strategies that improve trial recruitment would benefit both trialists and health research.

OBJECTIVES

To quantify the effects of strategies to improve recruitment of participants to randomised controlled trials.

SEARCH STRATEGY

We searched the Cochrane Methodology Review Group Specialised Register - CMR (The Cochrane Library (online) Issue 1 2008) (searched 20 February 2008); MEDLINE, Ovid (1950 to date of search) (searched 06 May 2008); EMBASE, Ovid (1980 to date of search) (searched 16 May 2008); ERIC, CSA (1966 to date of search) (searched 19 March 2008); Science Citation Index Expanded, ISI Web of Science (1975 to date of search) (searched 19 March 2008); Social Sciences Citation Index, ISI Web of Science (1975 to date of search) (searched 19 March 2008); and National Research Register (online) (Issue 3 2007) (searched 03 September 2007); C2-SPECTR (searched 09 April 2008). We also searched PubMed (25 March 2008) to retrieve "related articles" for 15 studies included in a previous version of this review.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of methods to increase recruitment to randomised controlled trials. This includes non-healthcare studies and studies recruiting to hypothetical trials. Studies aiming to increase response rates to questionnaires or trial retention, or which evaluated incentives and disincentives for clinicians to recruit patients were excluded.

DATA COLLECTION AND ANALYSIS

Data were extracted on the method evaluated; country in which the study was carried out; nature of the population; nature of the study setting; nature of the study to be recruited into; randomisation or quasi-randomisation method; and numbers and proportions in each intervention group. We used risk ratios and their 95% confidence intervals to describe the effects in individual trials, and assessed heterogeneity of these ratios between trials.

MAIN RESULTS

We identified 27 eligible trials with more than 26,604 participants. There were 24 studies involving interventions aimed directly at trial participants, while three evaluated interventions aimed at people recruiting participants. All studies were in health care. Some interventions were effective in increasing recruitment: telephone reminders to non-respondents (RR 2.66, 95% CI 1.37 to 5.18), use of opt-out, rather than opt-in, procedures for contacting potential trial participants (RR 1.39, 95% CI 1.06 to 1.84) and open designs where participants know which treatment they are receiving in the trial (RR 1.25, 95% CI 1.18 to 1.34). However, some of these strategies have disadvantages, which may limit their widespread use. For example, opt-out procedures are controversial and open designs are by definition unblinded. The effects of many other recruitment strategies are unclear; examples include the use of video to provide trial information to potential participants and modifying the training of recruiters. Many studies looked at recruitment to hypothetical trials and it is unclear how applicable these results are to real trials.

AUTHORS' CONCLUSIONS

Trialists can increase recruitment to their trials by using the strategies shown to be effective in this review: telephone reminders; use of opt-out, rather than opt-in; procedures for contacting potential trial participants and open designs. Some strategies (e.g. open trial designs) need to be considered carefully before use because they also have disadvantages. For example, opt-out procedures are controversial and open designs are by definition unblinded.

Cognitive factors and willingness to participate in an HIV vaccine trial among HIV-negative injection drug users

This cross-sectional study involving a cohort of injection drug users (IDU) examined the relationship between cognitive factors (HIV treatment optimism, self-efficacy and knowledge of vaccine trial concepts) as well as risk factors for seroconversion, and willingness to participate (WTP) in a preventive phase 3 HIV vaccine trial. Willingness to participate overall was 56%. In a multivariate analysis, for a 20-unit increase in a 100-point composite scale, self-efficacy was positively related to WTP (adjusted odds ratio [AOR]=1.95, 95% CI=1.40-2.70). HIV treatment optimism and knowledge of vaccine trial concepts were unrelated to WTP. Aboriginal ethnicity (AOR=3.47, 95% CI=1.68-7.18) and a higher educational level (>or=high school) (AOR=1.96, 95% CI=1.07-3.59) were positively related to WTP. This study provides information on WTP for an HIV vaccine trial. Limitations and future directions are also discussed.

Factors associated with willingness to participate in HIV vaccine trials among high-risk populations in South India

Abstract Successful conduct of any HIV vaccine trial (HIVVT) requires a high level of preparedness in the community. A cross-sectional study was conducted in Tamilnadu, India among 501 participants from six different risk groups to investigate their willingness to participate (WTP) in future preventive HIVVTs and to explore their knowledge and attitude toward preventive HIV vaccines. In total, 82% were willing to participate and the desire to be protected from HIV was the main reason for WTP. Perception of not being at risk was the major reason for refusal among married women. The knowledge scale showed a significant increase in scores after vaccine education. In all, 76% revealed the hope that there would be an effective vaccine in a few years and 71% hoped that the HIV vaccine would protect them from HIV infection. The main concern was the unknown efficacy of the vaccine (50%) and the effects of an HIV vaccine on participants' lives (51%). Overall, 76% agreed that sex without a condom would not be safe whether or not there was an HIV vaccine. To conclude, it is likely that high-risk volunteers will be willing to enroll in preventive HIVVTs. Addressing barriers and concerns by providing information through appropriate agencies will spell out success for preventive HIVVTs in India.

Community preparedness for HIV vaccine trials in the Democratic Republic of Congo

This paper reports on an assessment of community preparedness for HIV vaccine trials in the Democratic Republic of Congo. Formative research was conducted in the capital city of Kinshasa during the period October 2003 to March 2004 to answer questions pertinent to planning trials of a preventive HIV vaccine and to identify related issues. Twenty-seven in-depth interviews and two focus groups were held with potential trial participants and community leaders. Data was collected on the subjects of vaccines, HIV/AIDS and sexual behaviour, and an HIV vaccine. The study also sought to identify factors that motivate a person to volunteer for a vaccine trial or which are disincentives to participation, along with preparedness of the larger community for trials. Personal concerns for health and for the impact of the epidemic on families and country were common motivations for participation. The danger of an experimental vaccine and the stigma of a positive HIV antibody test as the result of vaccination are major concerns and disincentives. The health, educational, and local non-governmental sectors are identified as having important roles to play in assuring preparedness for trials, although significant challenges exist to achieving community preparedness.

Knowledge and attitudes regarding preventative HIV vaccine clinical trials in Italy: results of a national survey

We carried out a telephone survey to assess willingness to participate in HIV vaccine trials. The survey was conducted by interviewing randomly selected callers to the Italian National AIDS Help line. The questionnaire consisted of four sections: demographic information, knowledge about HIV vaccines and vaccines in general, factors related to participation in HIV vaccine trials, and acceptability of a future HIV vaccine. Over 50% of the sample had adequate knowledge about HIV and vaccines. Among the individuals interviewed, 37% would volunteer for a vaccine trial; those reporting high-risk behaviours were more likely to volunteer. Of the participants, 83% would agree to be vaccinated with a highly effective vaccine, and 92% would pay for the vaccine. Although the limits of telephone surveys should not be neglected, the results of this survey are encouraging.

Posttrial HIV vaccine adoption: concerns, motivators, and intentions among persons at risk for HIV

BACKGROUND

Suboptimal uptake of existing vaccines, potential obstacles specific to HIV/AIDS stigma and mistrust, and marked health disparities suggest that it is vital to investigate consumer concerns, motivations, and adoption intentions regarding posttrial HIV vaccines before a vaccine is publicly available.

METHOD

Nine focus groups were conducted with participants (n = 99; median age, 33 years; 48% female; 22% African American, 44% Latino, and 28% white) recruited from 7 high-risk venues in Los Angeles using purposive venue-based sampling. A semistructured interview guide elicited concerns, motivators, and adoption intentions regarding hypothetical U.S. Food and Drug Administration-approved HIV vaccines. Data were analyzed using narrative thematic analysis and Ethnograph qualitative software.

RESULTS

Concerns included vaccine efficacy, vaccine-induced infection, vaccine-induced HIV seropositivity, side effects, cost/access, trustworthiness, and relationship issues. Motivators included protection against HIV infection and the ability to safely engage in unprotected sex. Participants expressed reluctance to adopt partial efficacy vaccines and likelihood of increased sexual risk behaviors in response to vaccine availability.

CONCLUSION

Tailored interventions to facilitate uptake of future U.S. Food and Drug Administration-approved HIV vaccines and to prevent risk behavior increases may be vital to the effectiveness of vaccines in controlling the AIDS pandemic.

Correlates of HIV vaccine trial participation: an Indian perspective

Successful conduct of HIV vaccine trials in a population of great cultural diversity like India could be a challenge. Concerns, knowledge gaps and willingness to participate in future HIV vaccine trials were studied among 349 patients attending three sexually transmitted infections clinics and one reproductive tract infections clinic. Overall willingness to volunteer for HIV vaccine trials was 48%. Women and men at risk of HIV infection were willing to participate in the HIV vaccine trials. Factors associated with increased willingness to participate in these trials were awareness of current HIV vaccine efforts, realization of importance of vaccine for self, concern about adverse events and altruism.

Socio-behaviour challenges to phase III HIV vaccine trials in Sub-Saharan Africa

BACKGROUND

A number of countries in sub-Saharan Africa are preparing for HIV vaccine efficacy trials. Social and behavioural factors related to HIV transmission require examination in each setting where these trials are considered. As part of this, several countries have also recently begun preparatory research investigating relevant social and behavioural issues. There is a need for a review of the literature to help focus such research efforts in Sub-Saharan Africa.

OBJECTIVES

To examine key social and behavioural issues that may impact on the conduct of HIV vaccine efficacy trials in sub-Saharan Africa.

DESIGN

Literature review

METHODS

Major databases (PubMed, PsychInfo, EBSCOhost, and AIDSline) were searched for literature that discussed social and behavioural issues related to HIV vaccine trials. Three areas are highlighted as being particularly significant for HIV vaccine research: (1) willingness to participate in future HIV vaccine efficacy trials, (2) retention of participants in studies, and (3) sexual risk reporting during trials. For each of these topics, major findings from both developed and developing countries are described and avenues for further research are discussed.

RESULTS

There are few data from Sub-Saharan Africa regarding willingness to participate in HIV vaccine trials. Data on participant retention rates varies widely, and maintaining large cohorts of individuals within Phase III trials presents an important challenge. In addition, the possible impact of trial participation on sexual disinhibition, and response bias on sexual risk-reporting remain as issues for HIV vaccine trials in African contexts.

CONCLUSION

Social and behavioural research forms an important part of preparations for HIV vaccine efficacy trials, and there is a clear need for more research of this type in Sub-Saharan Africa. Innovative approaches are required to address issues such as willingness to participate in vaccine research, participant retention during efficacy trials, and the accurate reporting by participants of sexual risk behaviours.

Knowledge about vaccines and willingness to participate in preventive HIV vaccine trials: a population-based study, Rakai, Uganda

The purpose of the study was to assess knowledge and beliefs regarding vaccines and willingness to participate in HIV vaccine trials. A baseline survey assessed knowledge and attitudes toward vaccination and potential HIV vaccines among 14,177 participants aged 15-49 years, in a population cohort. Willingness to participate in HIV-preventive vaccine trials was assessed during a follow-up survey 10 months later after providing community education on HIV vaccines. Knowledge of the preventive utility of vaccines was high (71%), but higher in men than women (P<0.001), and increased with education levels (P<0.001). Vaccines were considered appropriate for children and women (99 and 88%, respectively), but not for adult men (28%). Participants felt that adolescents were the most appropriate subjects for HIV preventive vaccine trials (93.7%) but also thought that HIV-positive persons were eligible for trials (60.2%), and only 20% thought a preventive vaccine could help control HIV. HIV vaccine awareness increased from 68% at baseline to 81% at follow-up (P<0.001). Willingness to participate in HIV-preventive vaccine trials was 77%. Vaccine knowledge and willingness to participate in trials are high in this population. However, there still is need for education on the potential role of preventive HIV vaccines in the control of the epidemic and the importance of vaccination for men, especially in the context of an HIV vaccine.

The epidemiological contribution to the preparation of field trials for HIV and STI vaccines: objectives and methods of feasibility studies

Feasibility studies are an important component of preparations for efficacy field trials of vaccine candidates, but represent a neglected area in clinical trial literature. These studies are designed to identify cohorts of higher-risk individuals with sufficiently high incidence to support a vaccine trial; to determine the readiness of these individuals to participate in a trial; to develop cost-effective recruitment and retention strategies, educational methods that ensure ethical informed consent, and instruments that accurately assess risk behaviours; to measure incidence rates over time and the effect of risk reduction interventions on incidence; to contribute estimates of incidence and loss to follow-up rates to sample size calculations; to assess the level of acceptability of a future efficacious vaccine in the target population and, in the case of several viruses, to identify circulating subtypes. Feasibility study methods have been largely developed in the context of HIV, but may also be used in the preparation of preventive intervention trials for other STI.

Determinants of Enrollment in a Preventive HIV Vaccine Trial

OBJECTIVE

To compare hypothetical and actual willingness to enroll in a preventive HIV vaccine trial and identify factors affecting enrollment.

METHODS

Participants previously enrolled in an HIV vaccine preparedness study (VPS) in 8 US cities were invited to be screened for a phase 2 HIV vaccine trial. Demographic and risk characteristics of those enrolling, ineligible, and refusing enrollment were compared using the chi2 or Fisher exact test. Multivariable logistic models were used to identify independent predictors of refusal.

RESULTS

Of 2531 high-risk HIV-uninfected former VPS participants contacted for the vaccine trial, 13% enrolled, 34% were ineligible, and 53% refused enrollment. Only 20% of those stating hypothetical willingness during the VPS actually enrolled in this vaccine trial. In multivariate analysis, refusal was higher among African Americans and lower in persons >40 years of age, those attending college, and those with > or =5 partners in the prior 6 months. All racial ethnic groups cited concerns about vaccine-induced seropositivity; African Americans also cited mistrust of government and safety concerns as barriers to enrollment.

CONCLUSIONS

Steps can be taken to minimize potential social harms and to mobilize diverse communities to enroll in trials. Statements of hypothetical willingness to participate in future trials may overestimate true enrollment.

Lack of increased HIV risk behavior among injection drug users participating in the AIDSVAX B/E HIV vaccine trial in Bangkok, Thailand

OBJECTIVE

To determine whether HIV vaccine trial participation leads to increased risk behavior through beliefs about vaccine protection against infection.

METHODS

Changes in risk behavior were evaluated among 2545 injection drug users participating in the AIDSVAX B/E vaccine trial in Bangkok, enrolled from March 1999 to August 2000. Demographic characteristics, beliefs and risk behavior were assessed at baseline and every 6 months thereafter. Risk-reduction counseling was provided at every study visit. Generalized estimation-equation logistic regression analysis was used to study trends in risk behavior and associated factors.

RESULTS

Participants were 93.4% male, their median age was 26 years, and 67.2% had at least secondary education. At baseline, 61.3% were receiving methadone detoxification and 20.9% were receiving methadone maintenance. From baseline to the 12-month follow-up visit, injection drug use decreased from 93.8% to 66.5% (P < 0.001) and needle sharing from 33.0% to 17.5% (P < 0.001). Multivariate analyses showed earlier follow-up time (at baseline and 6 months) and believing the vaccine to be efficacious associated with more-frequent injecting; younger age and lower education associated with less-frequent injecting. Earlier follow-up time (at baseline), younger age, and injection of methamphetamine and midazolam were associated with more-frequent needle sharing; methadone treatment and injecting less than weekly were associated with less-frequent needle sharing.

CONCLUSIONS

Injection drug use and needle sharing decreased during the first 12 months of the trial. No increases in risk behavior in relation to beliefs about vaccine protection against HIV infection could be identified.

HIV Vaccine Development in Asia

HIV vaccine development in Asia was initiated eight years ago in Thailand and has since proven to be very active and successful. Thailand has played and is still playing a major role in leadership and has catalysed numerous initiatives with the constant support and active participation of the WHO-UNAIDS HIV Vaccine Inittative. Strong political commitment, willingness to streng hen national capacity building, and an open mind to international collaboration have been key elements of success.

HIV vaccine development in Thailand is not an isolated activity disconnected from HIV pre vention and care, two keystrategies implemented by the Royal Thai Government. The HIV Vac cine Development National Plan has been successful as part of a comprehensive National Plan for HIV/AIDS Prevention and Care. Thai researchers are now on the frontline and acting as peer advisers on HIV prevention and care, including HIV vaccine development not only for South-East Asian but also for African countries.

India is newly involved in HIV vaccine development. National and international collaborative initiatives between the Indian Council of Medical Research (ICMR), the US Vaccine Trial Network with Johns Hopkins University (funded by the US National Institute of Health) and more recently the International AIDS Vaccine Initiative have been launched, although they are still at very early stages of development. The National AIDS Control Organisation and ICMR have expressed strong political willingness and long-term commitment to HIV vaccine development for India. Strengthening national capacity building and reinforcement of national infrastructures are, however, preliminary conditions for a successful Indian programme.

Subject recruitment in critical care nursing research: a complex task in a complex environment

PURPOSE

This article serves to describe subject recruitment issues in a funded study in a the medical respiratory intensive care unit.

BACKGROUND

Subject recruitment can be difficult in the critical care environment. Inadequate recruitment can reduce the ability to detect treatment differences. Though causes of recruitment difficulty have been documented in medical trials, little is known concerning recruitment in critical care nursing studies.

METHODS/RESULTS

All patients admitted to a medical respiratory intensive care unit (ICU) were reviewed daily for study eligibility. Demographics and reasons for ineligibility and failure to consent were documented. Five hundred ninety-three patients were reviewed; 42 (7.1%) were enrolled; 457 (77.1%) were not eligible and not enrolled and 94 (15.8%) were eligible but not enrolled. Of those reviewed, 52% were male; 57% were black, and 41% were white. Of those eligible, but not enrolled, 40% were because of family unavailability for consent and 27% because of family unwillingness to consent. There were no significant differences in patient age or gender between those who consented and those who did not. However, those who did not consent consisted of a greater proportion of blacks than the population screened. Families' stated reasons for not consenting were primarily related to the family's stress level.

CONCLUSIONS

Conducting clinical studies in the critical care environment, enrolling subjects, and obtaining consent may be complicated by the critical nature of the patient's illness, and researchers must be aware of these issues for study success.

Recruiting volunteers for a multisite phase I/II HIV preventive vaccine trial in Thailand

Factors believed to be predictive of retention through the recruitment and screening processes for preventive HIV trials were investigated in a large multisite phase I/II HIV vaccine trial in Thailand. Retention through recruitment was equal to or greater than in previous smaller trials with similar populations. The data suggested that recruitment proceeded in a stepwise manner with different influences at each step. Demographic and motivational variables were most important in predicting retention in making and keeping screening appointments. Altruistic or mixed altruistic and nonaltruistic motives were associated with greater retention. Laboratory/medical variables appeared to be the main influence on retention during screening, although some volunteers withdrew for different reasons. The frequent presence of mixed (altruistic and nonaltruistic) motives at initial contact suggests that motivation for trials is more complex than has been previously acknowledged.

Prospective preference assessment: a method to enhance the ethics and efficiency of randomized controlled trials

The concomitant problems of underenrollment and selective enrollment limit the efficiency of many randomized controlled trials (RCTs). In addition, the traditional informed consent process is often inadequate to respect research participants' autonomy. Past efforts to overcome these problems are not universally applicable. A new method, called prospective preference assessment (PPA), is suggested as a way to simultaneously enhance participant accrual, identify groups of patients to whom a trial's results may apply, and promote participants' interests. PPA is a method by which investigators would evaluate potential trial participants' motivations for and concerns about enrolling in a planned trial prior to formal recruitment. The information provided by PPA would then be used to (1) modify the final trial design and conduct to make enrollment more attractive, and (2) identify ways in which the patients who do enroll may differ from those who do not, thereby elucidating the trial's generalizability. The methodologic and ethical advantages of this method are described, and potential barriers to the method's implementation are addressed. The added costs of prospectively assessing the views of potential research participants prior to initiating RCTs are considered in relation to the method's ability to enhance the value of the information to be obtained. It is concluded that PPA is a feasible approach to a more democratic and efficient research process and that its adoption would be consistent with current trends in health care.

Os múltiplos sentidos das vacinas para a Aids

Esta pesquisa visa contribuir para o desenvolvimento de práticas éticas de recrutamento de voluntários para ensaios de vacinas anti-HIV através da análise de entrevistas sobre os sentidos atribuídos às vacinas. Foram identificados quatro modelos de funcionamento das vacinas: terapêutico, onde são vistas como formas de medicamento; preventivo embrionário, centrado na função de proteção; de agência, focalizado na noção de anticorpos, e o modelo pleno no qual função e mecanismos são integrados. A disponibilidade e uso desses modelos têm importantes implicações para a decisão de ser (ou não) voluntário em ensaios de vacinas anti-HIV.

Women's willingness to participate in microbicide trials in Northern Thailand

To assess women's interests and concerns regarding participation in trials of microbicides in Chiang Rai, Thailand, we administered structured questionnaires. Before answering the questionnaire, women attended an educational session on microbicides and clinical trials. Of 370 participants, 82% correctly answered 8 or more of the 11 overall comprehension questions, indicating an adequate knowledge base among the women from which to answer questions about attitudes toward microbicide trials. The most common motivations for participating in a trial were "getting tested for HIV" and "doing something good for women's health." The greatest barrier to participation was women's fear that if they proposed use of a microbicide, their husbands might feel protected and thereby have more sex partners. Overall, 6.2% said they would be "definitely willing to participate," and 66.8% said they wanted to participate but wanted to think about it. Most women previously unacquainted with the concept of microbicides or clinical trial design displayed adequate knowledge of these subjects after the short educational session. If women's initial reactions are validated by actual willingness, surveys could prove valuable for selecting sites for microbicide trials, estimating enrollment rates, and tailoring trials to make them most acceptable to women.

Knowledge about vaccine trials and willingness to participate in an HIV/AIDS vaccine study in the Ugandan military

In preparation for HIV vaccine trials, knowledge about vaccines, willingness to participate in a vaccine study, and motivations for participation must be assessed. The Preparation for AIDS Vaccine Evaluation study assessed knowledge about vaccines and vaccine trials and willingness to participate in a hypothetical trial in 1,182 Ugandan military men (aged 18-30 years). Participants received education about vaccine trials and were interviewed during 24 months of follow-up observation. Its key findings are that: 1) throughout follow-up, most participants expressed willingness to participate in a hypothetical HIV vaccine trial; 2) participants are familiar with vaccines but do not clearly distinguish the use of vaccines for prevention or curing; 3) the most common reason given for being interested in participating in a vaccine trial was to be protected from HIV/AIDS; 4) trials' procedures (e.g., placebos, randomization, and blinding) were unfamiliar; and 5) knowledge about trials' procedures increased incrementally over follow-up, but at different rates for different concepts. These data demonstrate that potential vaccine trials' participants may benefit from vaccine trial education if adequate time is allowed to ensure that participants are able to master the complex information required for trial participation.

Who will enroll? Predicting participation in a phase II AIDS vaccine trial

BACKGROUND

The problems of underenrollment and selective enrollment may undermine AIDS vaccine trials. If prospective study subjects' stated willingness to participate (WTP) in hypothetical vaccine trials predicts future enrollment, then measuring WTP before recruitment may enhance the enrollment in, and ethics of, such trials.

METHODS

We prospectively studied changes over an 18-month period in the stated WTP in, and knowledge of, a hypothetical AIDS vaccine trial among 610 Philadelphia residents at high risk for HIV infection. Of these people, 499 were subsequently recruited to participate in an actual, phase II AIDS vaccine trial. We used multivariable logistic regression and the area under the receiver-operating characteristic (ROC) curve to model predictors of actual enrollment.

RESULTS

Actual enrollment rates were 8.3%, 6.8%, 15.8%, and 29.0% among those who had initially said they were "definitely not," "probably not," "probably," and "definitely" willing to participate, respectively (p =.006). The area under the ROC curve was 0.65, indicating a modest ability of stated WTP to differentiate those who enroll from those who do not. Knowledge of basic vaccine trial concepts, though unrelated to enrollment, increased over an 18-month period with repeated education sessions (p <.0001), whereas stated WTP declined over this same period (p <.0001).

CONCLUSION

Although other factors not captured by stated WTP may also influence future enrollment, prospectively assessing stated WTP may augment the validity of the informed consent process, help prevent underenrollment, and clarify the population from which the study sample is drawn.

Trial-related discrimination in HIV vaccine clinical trials

Participants in preventive HIV vaccine trials may experience negative social consequences of trial participation, including problems related to a vaccine-induced positive HIV antibody test, yet few vaccine studies have reported on this issue. From October 1995 through November 1998, 1516 AIDS Vaccine Evaluation Group (AVEG) volunteers were assessed for reports of trial-related discrimination (TRD). Ninety TRD events were reported by 76 (5%) of 1516 volunteers. The most commonly reported incidents (n = 52, 57.8%) were negative reactions of friends, family, and co-workers to the volunteer. Few incidents (approximately 10%) were reported as linked to HIV testing. The majority of events (n = 47, 52%) were described by volunteers as "resolved" at the time of reporting, 36 (40%) as "not resolved," and for 7 (8%) events volunteers did not report resolution status. Reported incidents were analyzed by logistic regression to determine their association with the volunteer's age, sex, race, sexual orientation, and HIV risk category. There was no association between volunteer characteristics and TRD. Logistic regression and analysis of variance (ANOVA) were used to analyze association of trial sites with the number of TRD events reported. After controlling for site variation in data collection and reporting, no significant differences were found between the sites in terms of the number or type of TRD reported. Fears that TRD would be widespread and severe have not been borne out by this analysis. While the results of this study are reassuring, they should be interpreted with caution, as it is unclear whether these results may be extended to phase III trials enrolling large numbers of individuals at higher risk of HIV acquisition.

Therapeutic trials in HIV infection: which benefits for which patients?

PURPOSE

The purpose of our study was to make an assessment of the HIV patients' overall opinion of therapeutic trials, to analyze the motivations and the reasons linked to this perception, and to determine if their involvement in a therapeutic trial is a help or a hindrance to their treatment.

METHOD

All the inpatients and outpatients attending the Dijon University Hospital AIDS day care unit during the first 4 months of 1999 were given an anonymous questionnaire designed to record the patients' attitudes toward therapeutic trials, their motivations, and the perceived risks. The questionnaire was often completed in consultation with a psychoanalyst.

RESULTS

Two hundred and seven (207) patients were surveyed; 194 of them had a favorable opinion of therapeutic trials. The main motivations to take part in a therapeutic trial were altruistic. In contrast, individualistic considerations and relational motivations (such as to modify the relationship between the caregiver and the patient) were more closely associated with a negative perception.

CONCLUSION

Most of the patients will benefit or at least will not be harmed by being involved in a trial. However, the patients' attitudes toward the principle of therapeutic trials have to be determined before these patients are included in a given therapeutic trial. This is necessary to avoid the risk of subsequent medical care being altered because participation was either induced or compelled.

Willingness to participate in HIV-1 vaccine trials among young Thai men

OBJECTIVES

Willingness to participate in HIV-1 vaccine trials and associated factors were investigated in a sample of 2670 Royal Thai Army conscripted recruits.

METHODS

Self administered questionnaires were used. Data were collected during the final visit of a longitudinal cohort study of HIV-1 epidemiology. Cross sectional analysis of data from this visit was performed.

RESULTS

32% of the respondents reported they would "definitely" join an HIV-1 vaccine trial. Greater willingness was associated with perceived risk of HIV-1 infection and a desire to help Thai society, although tangible incentives and intentions to reduce condom use in a vaccine trial also were associated with increased willingness. Concerns about physical harm and anticipated social pressure from family not to join were the most substantial impediments to willingness. Concerns about "social harm" (for example, participation would give appearance of having AIDS virus, a partner might refuse sex) also appeared to inhibit interest in joining trials and approached significance.

CONCLUSIONS

Willingness to participate was somewhat greater than in other investigations of non-injection drug user (IDU) cohorts in Thailand, with fewer concerns expressed about physical harm. Motivations appear to involve tradeoffs among perceived risk, anticipated social pressure, altruism, and tangible rewards. The absence of significant problems associated with vaccine trials to date, along with the presence of educational interventions in the study may help explain the lower level of concerns here relative to other Thai studies.

Willingness of injection drug users to participate in an HIV vaccine efficacy trial in Bangkok, Thailand

We assessed willingness to participate in an HIV recombinant gp120 bivalent subtypes B/E candidate vaccine efficacy trial among 193 injection drug users (IDUs) attending drug treatment clinics in Bangkok, Thailand. IDUs previously enrolled in a prospective cohort study were invited to group sessions describing a potential trial, then completed questionnaires assessing comprehension and willingness to participate. A week later, they completed a follow-up questionnaire that again assessed comprehension and willingness to participate, as well as barriers to and positive motives for participation, with whom (if anyone) they talked about the information, and whether others thought participation was a good, bad, or neutral idea. At baseline, 51% were definitely willing to participate, and at follow-up 54%; only 3% were not willing to participate at either time. Comprehension was high at baseline and improved at follow-up. Participants who viewed altruism, regular HIV tests, and family support for participation as important were more willing to volunteer. Frequency of incarceration and concerns about the length of the trial, possible vaccine-induced accelerated disease progression, and lack of family support were negatively associated with willingness. Overall, IDUs comprehended the information needed to make a fully informed decision about participating in an rgp120 vaccine efficacy trial and expressed a high level of willingness to participate in such a trial.

Some important issues in the planning of phase III HIV vaccine efficacy trials

Given that interesting HIV vaccine candidates, including live preparations and DNA plasmids, exist and that the first phase III vaccine (AIDSVAX) testing is due to begin this summer, 1998, in the U.S., adequately addressing trial preparedness is a pressing issue. Despite double-blind randomized controlled clinical trial design, there may be difficulties with interpretation and use of the usual measures of vaccinal efficacy and calculation of sample size. Difficulties arise from vaccine characteristics (e.g. mode of action, time-lag, waning) and population heterogeneities (e.g. differences in susceptibility, sexual behaviour, mixing preferences) causing frailty effects that can exacerbate bias and time-dependent effects already known to exist in simple cases. Since vaccine properties, particularly mode of action, are unlikely to be known before the onset of clinical trials, choosing an efficacy measure and the associated analyses and sample size calculations will be problematic. Interim analyses designed to decide whether a study will be prolonged may be tenuous if based on a time-dependent measure and will influence sample size determination. Despite shortcomings, general recommendations can be made to minimise pernicious effects. The objectives of this paper are principally to review the current state of knowledge of the different stages in the preparation of large phase III HIV vaccine efficacy trials, the methodological difficulties related to their design, and the analysis of data collected from them. Mathematical models and trial simulations are used to demonstrate that further research is necessary to study the behaviour of vaccine efficacy measures under heterogeneous conditions of population, vaccine action, and trial design and identify a time-independent efficacy measure. Alternative methods to validate sample size calculations have to be developed in older to reduce the chances of unnecessary economic and human cost in phase III HIV vaccine trials.

Preventing discrimination against volunteers in prophylactic HIV vaccine trials: lessons from a phase II trial

CONTEXT

Preventive HIV vaccines can temporarily cause uninfected individuals to have positive results on HIV testing. As preparations are underway to mount larger efficacy trials, the social risks of trial participation should be studied.

OBJECTIVE

To describe frequency of HIV testing and discrimination among participants in a preventive phase II HIV vaccine trial.

PARTICIPANTS

266 vaccine trial volunteers were eligible; 247 participated in a confidential survey.

RESULTS

63 volunteers (26% of respondents) reported 185 HIV tests during the prior 12 to 24 months; most tests were for other research studies, health care, insurance, incarceration, or employment. Only 5 volunteers reported having positive HIV test results. Volunteers reported 99 adverse social incidents or problems, 53 of which were related to the trial. The most common type of event occurred when volunteers disclosed their trial participation and were mistakenly presumed to be infected with HIV. Few reported difficulty obtaining insurance, job loss, and inadvertent disclosure of their participation in the trial.

CONCLUSION

In this vaccine trial, few serious social harms were reported. Those who conduct HIV tests for insurance, employment, health care, or other reasons should be made aware that HIV vaccines can cause false-positive HIV test results. Those planning future trials must continue to provide needed support to volunteers. Social harms should be monitored with the same vigilance accorded to physical harms.

Attitudes about human immunodeficiency virus immunization: the influence of health beliefs and vaccine characteristics

BACKGROUND AND OBJECTIVES

The development of a vaccine to prevent human immunodeficiency virus (HIV) infection is a highly desirable goal. However, there may be a number of psychosocial barriers to HIV vaccine acceptance. The purpose of this study was to begin to examine some factors that might influence attitudes about HIV immunization.

GOAL

To evaluate the relationship of health beliefs and vaccine characteristics to acceptability of hypothetical HIV immunization.

STUDY DESIGN

The subjects were 222 college students who completed self-administered questionnaires that addressed health beliefs, vaccine characteristics, and acceptability of hypothetical HIV vaccines.

RESULTS

Health beliefs independently predictive of HIV vaccine acceptability included perceived susceptibility to HIV, perceived nonmembership in a traditionally defined acquired immune deficiency syndrome (AIDS) risk group, and fear of the vaccine causing AIDS. Of the vaccine characteristics, efficacy influenced vaccine acceptability most strongly, followed by type of vaccine.

CONCLUSION

These results suggest that universal HIV vaccine acceptance cannot be assumed and that vaccine characteristics and individuals' health beliefs are likely to influence decisions regarding HIV immunization.

HIV vaccine acceptance among heterosexual clients of a sexually transmitted diseases clinic

We evaluated the willingness of clients at a large urban sexually transmitted diseases (STD) clinic in the southeastern United States to participate in future trials of preventive vaccines for HIV type 1 (HIV-1). A single trained interviewer administered an oral survey instrument to STD clinic clients over a 4-week enrollment period. The participants were 167 randomly selected clients (90 men and 77 women), most of whom were young, African-American heterosexuals. Risk behaviors for HIV-1 infection were highly prevalent. Overall, 67% of clients expressed willingness to consider participation in an HIV-1 vaccine trial. By univariate analysis, prior HIV-1 testing was significantly associated with willingness to participate (P = 0.04). Multivariate analysis revealed that female gender (P = 0.05) and prior HIV-1 testing (P = 0.03) were significant predictors of willingness to participate.

HIV-1 risk and vaccine acceptability in the Ugandan military

Between July and October 1993, 570 19- to 22-year-old volunteers were screened for HIV-1, with a resulting seroprevalence rate of 18.3% (95% CI: 14.0%, 22.6%). A cohort of 249 HIV-1-noninfected military recruits in the Ugandan Peoples' Defense Forces was followed prospectively for up to 18 months to document rates of HIV-1 seroprevalence, seroconversion, and knowledge and attitudes related to vaccine acceptability. The HIV-1 seroincidence rate was 3.56 per 100 person-years (95% CI: 1.49, 5.62) over 309 person-years of observation. At the 3- and 12-month visits, subjects were interviewed on issues of acceptance and knowledge about vaccines, including anti-HIV vaccines in particular. More than 90% believe that HIV vaccines will not cause HIV infection, and if offered, 88% report that they would take the vaccine if they were not already infected. Nonvaccine prevention methods were considered less reliable; monogamy and condom use were considered effective by only 33.5% and 69.3% of the cohort respectively. After completing the vaccine acceptability questionnaire at the 12-month visit, subjects were offered an approved polyvalent meningococcal vaccine as an indicator of general vaccine acceptance. All subjects reported receiving at least one previous vaccination, and 95% willingly accepted the meningococcal vaccination. The Ugandan military is a stable population at substantial risk for HIV-1 infection and may be a suitable population for vaccine efficacy trials.

Hepatitis B immunization: a potential incentive to HIV vaccine trial participation in Thailand?

To assess the effectiveness of hepatitis B immunization as an incentive to retention in HIV seroincidence studies and future HIV vaccine trials in northern Thailand, subjects enrolled in three HIV seroincidence cohorts were screened for hepatitis B markers and seronegatives were offered free hepatitis B immunization. Cohorts studied included female commercial sex workers (CSWs), male sexually transmitted disease (STD) patients, and recently discharged military conscripts. Subjects who agreed to the immunization program were compared with those not enrolled to determine the utility of immunization as an incentive to cohort retention. Full immunization was achieved for 273 (89.5%) of 305 vaccinees; only 323 (60.6%) of 533 subjects not immunized completed the same follow-up visits (OR = 1.49, 95% and CI = 1.27, 1.75). Hepatitis B vaccination was a significant incentive for completion of the follow-up program. The vaccination program had the greatest effect on the CSWs; a similar effect was seen for male STD patients, but not for discharged conscripts. Despite the immunization program, follow-up rates at 12 months were similar in the immunized and nonimmunized groups.