Sexually Transmitted Diseases: How Much Do Adolescents Know?

Research Article

Austin J Public Health Epidemiol. 2016; 3(2): 1035.

Sexually Transmitted Diseases: How Much Do Adolescents Know?

JGargiani N¹, Verzuri A²*, Nante N1,2 and Messina G1,2

¹Department of Molecular Medicine and Development, University of Siena, Italy

²Department of Public Health, University of Siena, Italy

*Corresponding author: Agnese Verzuri, Department of Public Health, University of Siena, Italy

Received: January 28, 2016; Accepted: February 05, 2016; Published: February 08, 2016


Background: Sexually Transmitted Diseases (STD) are a major area of world public health. Behavior at risk, often encountered in the very young, is among the determinants of their incidence. The aim of this study was to establish how aware adolescents are of the risk of STD.

Methods: This cross-sectional study was conducted in May and June 2014 in three high schools in the town of Arezzo. The data was obtained with an anonymous questionnaire. Sample size, calculated by EpiInfo (C.I. 99%) was 390. The t-test and ANOVA were used to compare males and females and the different school years (classes); the Odds Ratio was used to evaluate propensity to answer the questions correctly by females and males and in 3rd years compared to 4th and 5th years. The number of questionnaires analysed was 603.

Results: The mean age of participants was 17.8 years (SD 1.01); 62.2% were female. A correct definition of STD was given by 64.3%: males outnumbering females (OR 1.48, p<0.05) and 5th year outnumbering 3rd and 4th years (p<0.001). A high percentage of students (98.5%) knew that HIV was sexually transmitted and awareness was also high with regard to syphilis (79.6%) and Candida infection (72.3%). Older students were less informed about HPV that younger students (OR 0.55; p<0.001). Exchange of syringe needles between drug abusers and unprotected sexual intercourse were recognized as risky for STD by 92.5% and 78.2% of the sample, respectively; 66.4% knew that ignorance was associated with situations of high risk. The percentage of respondents using condoms for intercourse with casual partners was 85.4%, falling to 42.9% for habitual partners; only 55.9% knew that the contraceptive pill does not protect against infection.

Conclusion: In general, respondents’ awareness of the problem showed many gaps, especially regarding behaviour exposing to risk of infection and regarding methods of protection. Since this knowledge is indispensable for risk perception, projects to inform and raise awareness are important to promote behaviour that will prevent transmission of STD, especially in the very young.

Keywords: Sexually transmitted diseases; Adolescents


Sexually Transmitted Diseases (STD) are a major problem of public health at world level, both in industrialized and developing countries, also because if they are not diagnosed and treated early they can have major health sequelae [1]. The high incidence of STD can be attributed to behaviour at risk, especially in the young, as well as the numerous etiologies and drug resistance [2]. Indeed, the World Health Organisation (WHO) reports that the impact of STD exceeds 400 million new cases in women and men between 15 and 49 years of age each year [3]; of these, at least 111 million cases regard persons less than 25 years of age. In 2010, a WHO study aimed at describing sexual behaviour in the young showed that 22% of girls and 26% of boys had already had sexual intercourse for the first time by the age of 15 years [4]. The 15 to 25-year age range constitutes 25% of the sexually active population and is particularly at risk because STD may often be asymptomatic. Besides, social stigma can negatively affect the attitude of the very young towards prevention [5].

In Europe, many studies have shown that adolescents are aware of HIV, whereas confusion reigns regarding the use of condoms and contraceptive methods [6]. According to Italian studies, the main risk factor for STD is incorrect or no use of condoms [7-9].

The aim of the present study was to evaluate awareness of young people regarding STD, to understand the extent to which this influences their behaviour, and to pinpoint critical defects in their knowledge/behaviour to remedy with health education campaigns.

Materials and Methods

Study setting and design

This cross-sectional study was conducted in May and June 2014 at three high schools in the town of Arezzo. The population involved consisted of young adolescents aged 15-20 years, in the 3rd, 4th and 5th year classes. The information was collected by anonymous printed questionnaires that were distributed in agreement with teachers and principals.


To have a correct representation of the phenomenon we set a minimum sample size. According to ISTAT, the population of Arezzo in the age range of interest was 4727. To avoid underestimation, we used a expected prevalence of 50% and postulated a confidence interval of 99%. Using EpiInfo 7, we calculated that the minimum number of subjects to interview was 390.


The questionnaire, previously used for research by the University of Ferrara [10], was accompanied by a letter in which the study and its motivations were presented. Students were reassured that their answers would by completely anonymous. The questionnaire consisted of a demographic part (age, gender, class) and five closed questions regarding:

1. The definition of STD;

2. Identification of STD in a list of different diseases;

3. Evaluation of risk of transmission of STD in a list of situations at risk and not at risk;

4. Frequency of condom use;

5. Evaluation of the safety of different methods of contraception.

Students were giving 20 minutes to answer autonomously, and once complete the questionnaire was posted in a closed box. The questionnaires were then processed with a Remark Office OMR, version 2 optical readers (Remark Product Group, 301 Lindenwood, Suite 100 Malvern, Pennsylvania, USA) that quickly and automatically recorded the data, avoiding errors. The resulting database had the following fields: gender, age (15-19+ years), class (3rd, 4th, 5th) and the replies to the five questions. In order to evaluate overall knowledge on the topic, a point score was calculated by summing: one point for correct definition of STD; one point for each STD identified in the list; one point for identifying each situation at risk for transmission of STD; one point for correct evaluation of the safety of the different contraceptive methods. The maximum point score (all correct answers) was 48.

Statistical analysis

After descriptive analysis of the sample (means, percentages and standard deviations), the Shapiro-Wilk test was applied to test for normal distribution of continuous variables and comparisons were made between males and females and the different classes by t-test and ANOVA. The Odds Ratio was used to evaluate propensity of females and males, and of 3rd class versus 4-5th classes, to answer the questions correctly. Significance was set at p<0.05. The data thus organised was analysed by software Stata ® SE, version 12.1 (Stata Corp, College Station, Texas, USA).


The number of questionnaires handed out was 630 and 603 (95.7%) were returned. Mean age of the responder population was 17.8 years (SD 1.01), with girls comprising 62.2% of the sample. Stratifying by “age”, the population was composed as follows: 15 years 0.3%; 16 years 9.6%; 17 years 28.1%; 18 years 36.2%; 19 years 22.1% and 19+ years 3.7%; and by “class”: third year 24.1%; fourth year 34.5%; fifth year 41.4%.

The mean point score for general knowledge on the topic was 33.7 (SD 4.3), without any significant difference between genders, whereas ANOVA revealed differences between classes (p<0.01) with mean scores of 32.5 (SD 3.9) in third year, 33.5 (SD 4.1) in fourth year and 34.6 (SD 4.5) in fifth year (Figure 1).