Trends in Sexual Behavior, Testing, and Knowledge in Young People; 2006–2011

Abstract

Cross-sectional surveys were conducted annually from 2006 to 2011 at a music festival. Eight thousand one hundred sixty-five young people completed surveys. STI testing rates increased over time, but there was an increase in the prevalence of some sexual risk behaviors and little improvement in STI knowledge between 2006 and 2011.

In Brief

We report trends from community-based surveillance of young people. Between 2006 and 2011, STI testing increased, the prevalence of some risk behaviours increased, and STI knowledge did not change substantially

Annual notifications of chlamydia in Australia increased by 57% from 47,434 in 2006 to 74,305 in 2010.¹ Although some of this increase can be attributed to increased chlamydia testing, there is also evidence of increasing chlamydia incidence.^2,3 Risk factors for chlamydia acquisition in young people include unprotected sexual intercourse, multiple sexual partners, and new sexual partners.^4,5

Monitoring trends in sexual behavior is a vital public health measure, assisting interpretation of trends in sexually transmitted infections (STI) notifications,⁶ and evaluation of sexual health promotion programs.⁷ In Australia, most sexual behavior surveillance targets those at high risk of STI, such as men who have sex with men⁸ and sexual health clinic attendees.⁹ Surveillance studies of young people are generally based in settings such as households¹⁰ and schools,¹¹ which may be biased by missing high-risk young people who do not live with their parents, do not have a landline telephone, or who do not attend school. Most young people fall somewhere between high- and low-risk groups, and it is important to identify and reach them to collect data on behavioral trends.

Conducting behavioral surveillance at a music festival provides a unique opportunity to access a large number of at-risk young people outside residential, educational, or clinical settings. We previously reported on a decrease in overall sexual risk behaviors trends from 2005 to 2008 among young people attending a music festival in Melbourne.¹² Since 2008, STI notifications in Australia have continued to increase, so it is important to monitor behavior trends during this period. Here, we provide updated trends in sexual behavior, sexual health knowledge, and testing in this population, from 2006 until 2011.

Cross-sectional surveys were conducted annually from 2005 to 2011 at the Big Day Out music festival in Melbourne, Australia (available at: www.bigdayout.com). Methods have been reported previously.^12,13 Each year, we procured a market stall and invited people aged between 16 and 29 years to complete a brief paper questionnaire about “Sex, drugs, and rock’n’roll.”

Questionnaires took 10 to 15 minutes to complete. Topics covered by questionnaires varied slightly each year, but key questions remained the same (with the exception of the 2005 pilot questionnaire; this year is excluded from analyses). In 2008, a shorter questionnaire was used to enable recruitment of a greater number of participants.

In 2006 and 2008, the festival was also used to recruit participants for subsequent health promotion intervention studies.^14,15 In 2009, survey participants were offered chlamydia testing by providing a mailed urine sample at home.¹⁶ This may have biased responses to the knowledge statement Chlamydia can be diagnosed with a urine test, thus 2009 data were excluded from trend analysis on this statement.

Partner types were defined on the questionnaire as regular (boyfriend/girlfriend/partner) or casual (all other partners). A new partner was defined as someone with whom sex had occurred for the first time in the previous 3 months. An STI test included tests for any infection but excluded pap smears. STI knowledge was assessed with a series of statements, which could be deemed by participants as “true,” “false,” or “don’t know”; “don’t know” was considered incorrect. Condom use was consistent (always used a condom) or inconsistent (usually, sometimes, or never used a condom).

Analysis was conducted in STATA 11. Temporal trends in reported behaviors were assessed by including “year of survey” as a continuous variable in logistic regression and adjusted for age and gender, where odds ratios represent the average change per year in reported behaviors. Individuals were not tracked over time. Participants who reported never having had sex were excluded from trend analysis on all behavioral questions but were included in STI knowledge outcomes. Differences in STI testing between groups were determined using a t test.

Ethics approval was granted by the Victorian Department of Human Services (2005–2007) and the Alfred Hospital (2008–2011).

A total of 8165 young people completed questionnaires; 60% were female and the median age was 20.8 years (Table 1). Demographic characteristics varied slightly across the years, most notably in 2008 when more participants in older age-groups were recruited.

TABLE 1: Demographics of Participants, by Year

Overall, 83% reported ever having had sex, with no change over time (Table 2). Adjusting for age and gender, there was a significant decrease in the percentage reporting regular partners and a significant increase in the percentage reporting casual partners. Consistent condom use with casual partners decreased significantly.

TABLE 2: Association Between Selected Behaviors and Year of Survey

The percentage reporting an STI test in the past 2 years increased significantly between 2006 and 2011, within all subgroups analyzed (Table 3). Testing was more frequently reported by females than males (P < 0.01), those aged 20 to 29 than those aged 16 to 19 (P < 0.01), and those residing in metropolitan Melbourne than rural Victoria (P < 0.01).

TABLE 3: Association Between STI Testing in the Past Two Years and Year of Survey, by Sub-group

The proportion knowing that chlamydia can cause infertility and that STIs may be asymptomatic increased over time (Table 4). The 3 questions related to diagnosis and treatment of STI were the most poorly answered (between 35% and 53% correct), with no change over time.

TABLE 4: Association Between STI Knowledge and Year of Survey

The results of this study suggest increased prevalences of some sexual risk behaviors among young people from 2006 to 2011; reporting regular partners decreased, reporting casual sexual partners increased, and the percentage consistently using condoms with casual partners decreased over time. In addition, consistent condom use with multiple, regular, and new partners remained at low levels. These behaviors may result in negative outcomes, such as STI acquisition or unplanned pregnancy.

STI testing is an important public health measure in STI control, and has been the focus of recent health promotion campaigns and public policies.^17,18 Some progress is evident; reported STI testing increased between 2006 and 2011. Testing was less common in males and in those aged <20 years; this parallels Australian laboratory surveillance findings.¹⁹ Worryingly, these groups are also more likely to return a positive test.¹⁹

Testing among participants residing in rural Victoria was less common than those in Melbourne. Past research shows that rural general practitioners are less likely to offer chlamydia testing than their metropolitan counterparts.²⁰ Young people report various difficulties in accessing appropriate health services in rural areas, including confidentiality concerns and lack of transport to access services.^21,22 This study provides some evidence that rural youth are catching up to their city peers as the percentage tested increased by an average of 9% each year (compared with 5% per year in Melbourne).

Between 2006 and 2011, reporting of regular partners decreased, whereas reporting of casual partners increased. This possibly represents a change in how young people define their behavior as opposed to a change in behavior. However, even if young people perceive otherwise, regular partners are not necessarily less risky than casual partners.^5,23 Many surveillance systems, research projects, and evaluations differentiate between casual and regular sexual partnerships,^4,5,23–25 but few researchers have explored how young people interpret these terms. Further investigation is needed to better understand these findings and to design appropriate health promotion messages.

Correct responses to 2 knowledge statements increased over time: People infected with STIs often do not have any symptoms, and Chlamydia can make women infertile. Both of these facts were publicized in an Australian government campaign, implemented in mid-2009.¹⁸ The most poorly answered statements (with no change over time) were those related to STI diagnosis and treatment options (urine testing, Pap smear testing, and antibiotic treatment). This is concerning as lack of knowledge about testing, and treatment options may be a barrier to STI screening.^26–28 Health promotion campaigns should encourage testing by providing practical information about the options available.

This study has limitations. In this repeat cross-sectional study, differences observed in sexual behavior each year may be because of differences in the sample selected. The age and gender profile of the sample varied each year, which was accounted for in multivariate analysis, but there may have been other characteristics, which were not measured or controlled for. The degree to which these convenience samples are representative of all festival attendees or the Australian population is not entirely known. Compared with the Australian population, our sample is more highly educated and reported more frequent drug use, binge drinking, and sexual risk behaviors.^13,29 Even if our study participants are not representative of young Australians in general, they clearly remain an important group to study as they reported high levels of sexual risk behaviors and should be targeted—and reached—by sexual health promotion campaigns. To gain a clear understanding of young people’s sexual risk behaviors, it would be useful to combine findings with information from surveillance conducted in schools, clinics, households, and other venues to improve geographical and population coverage.

Although reported STI testing increased, the prevalence of some sexual risk behaviors increased, and we observed little improvement in STI knowledge between 2006 and 2011. Novel and effective health promotion strategies to increase knowledge and testing and reduce risk behaviors (such as evidence-based sexual education at schools,^30,31 health promotion using social network websites³² and mobile phones,¹⁴ increasing rates of health care provider initiated testing,³³ and community-based chlamydia screening³⁴), are urgently needed among this population group.