Effects of the SATZ teacher-led school HIV prevention programmes on adolescent sexual behaviour: cluster randomised controlled trials in three sub-Saharan African sites.

In this study, the effects on young adolescent sexual risk behaviour of teacher-led school HIV prevention programmes were examined in two sites in South Africa (Cape Town and Mankweng) and one site in Tanzania (Dar es Salaam). In Cape Town, Dar es Salaam and Mankweng, 26, 24 and 30 schools, respectively, were randomly allocated to intervention or comparison groups. Primary outcomes were delayed sexual debut and condom use among adolescents aged 12-14 years (grade 8 in South Africa and grades 5 and 6 in Tanzania). In total, 5352, 4197 and 2590 students participated at baseline in 2004 in Cape Town, Dar es Salaam and Mankweng, respectively, and 73% (n = 3926), 88% (n = 3693) and 83% (n = 2142) were retained 12-15 months later. At baseline, 13% (n = 224), 5% (n = 100) and 17% (n = 164) had had their sexual debut, and 44% (n = 122), 20% (n = 17) and 37% (n = 57) of these used a condom at last sex, respectively. In Dar es Salaam, students in the intervention were less likely to have their sexual debut during the study (OR 0.65, 95% CI 0.48-0.87). In Cape Town and Mankweng, the intervention had no impact. The current interventions were effective at delaying sexual debut in Dar es Salaam but not in South Africa, where they need to be supplemented with programmes to change the environment in which adolescents make decisions about sexual behaviour.

Personal and social-environmental correlates of objectively measured physical activity in Norwegian pre-adolescent children.

The aim of this study was to examine modifiable biological, psychological, behavioral and social-environmental correlates of physical activity among 1129 Norwegian 11-year-old children within a cross-sectional sample from the HEalth In Adolescents study. Physical activity was assessed by accelerometer, and weight and height were measured objectively. Age- and gender-specific cut-off points proposed by the International Obesity Task Force were used to define body mass index. Social-environmental variables were self-reported by questionnaire. Hierarchical regression (linear mixed models) revealed that normal weight children scored higher on percentage daily moderate-to-vigorous physical activity [% daily moderate to vigorous physical activity (MVPA)] than overweight/obese children (P<0.001). Self-efficacy (P<0.01) and perceived social support from friends (P<0.01) were positively associated with children's % daily MVPA, and a negative association was found for computer/game-use on weekends (P<0.01). A moderator effect of weight category (normal vs overweight/obese) in the relationship between computer/game-use on weekends and % daily MVPA was detected (P<0.05), reflecting that higher computer/game-use on weekends was associated with lower % MVPA among the overweight/obese, but not among the normal weight. Modifiable correlates from multiple domains accounted for 14% of the variance in % daily MVPA. Prospective and intervention studies are needed to examine whether these factors act as mediators for physical activity change in pre-adolescent children.

Overweight and waist circumference among Norwegian 11-year-olds and associations with reported parental overweight and waist circumference: The HEIA study.

AIMS: The aim of this paper is to investigate anthropometric characteristics in 11-year-old Norwegian by gender and parental education, and to study associations between adolescents' overweight and waist circumference (WC) and maternal and paternal overweight and WC. METHODS: A total of 1483 adolescents, 1156 mothers, and 1016 fathers participated in the baseline survey of the HEalth In Adolescents (HEIA) study (September 2007). Anthropometric measures of the adolescents were assessed by project staff according to standard procedures. Self-reported data about pubertal status were collected through questionnaires. Parental education and anthropometric measures of parents were collected by self-report. RESULTS: The prevalence of overweight (including obesity) determined by the cut-offs for body mass index (BMI) suggested by the International Obesity Task Force was 14.6% among girls and 13.6% among boys. The highest prevalence of overweight was observed among adolescents with parents who had less than 12 years of education (18.8%). Overweight and WC in girls was strongly associated with maternal overweight and WC. For boys, overweight and WC was strongly associated with both maternal and paternal overweight and WC. CONCLUSIONS: There was a social gradient in anthropometric characteristics and overweight rates among Norwegian 11-year-old adolescents. Maternal overweight and WC was associated with overweight and WC in girls and boys, while paternal overweight and WC were associated with overweight and WC in boys. The results indicate that mothers are key persons in prevention of overweight among adolescents, despite gender. Fathers are important as role models for their sons. Targeting parental overweight/ obesity could be a strategy in future interventions.

Design of a 20-month comprehensive, multicomponent school-based randomised trial to promote healthy weight development among 11-13 year olds: The HEalth In Adolescents study.

BACKGROUND AND PURPOSE: The lack of effective school-based interventions for preventing obesity in children has caused a call for longer duration of interventions and better reporting on design and evaluation methodology. The purpose of this paper is to present the development of the intervention, the design of the effectiveness study, and the test-retest reliability of the main outcome measures in the HEalth In Adolescents (HEIA) study. METHODS/DESIGN: The HEIA intervention programme was developed based on literature reviews, a social ecological framework, and focus groups. The intervention aimed to increase total physical activity (PA) and consumption of fruit and vegetables and to decrease screen time and consumption of sugar-sweetened beverages. The intervention programme consisted of a classroom component, including dietary behaviour lessons, computer tailoring, fruit/vegetable and PA breaks, and posters, and an environmental component including active transport campaigns, equipment, suggestions for easy improvements of schoolyards, inspirational courses for teachers (all with regards to PA), and fact sheets to parents. The effect of the intervention programme is evaluated in a cluster randomised controlled trial design (intervention = 12 schools, control = 25 schools) including process evaluation. Main outcomes include anthropometry, PA, screen time, and consumption of fruit, vegetables, and sugar-sweetened beverages. A 2-week test- retest study was conducted among 114 pupils. Determinants of the behaviours were assessed. Similar data were collected from parents. Children's PA was measured objectively by accelerometers. CONCLUSIONS: The HEIA study represents a theoretically informed randomised trial comprising a comprehensive set of multilevel intervention components with a thorough evaluation using reliable outcome measures. The study will contribute to a better understanding of determinants of healthy weight development among young people and how such determinants can be modified.

Does socio-economic status moderate the associations between psychosocial predictors and fruit intake in schoolchildren? The Pro Children study.

This study tested whether socio-economic status (SES) moderated the association between the psychosocial constructs included in the attitude-social influence-self-efficacy (ASE) model and fruit intake in Norwegian schoolchildren. The sample consisted of 962 Norwegian sixth graders, mean age 11.3 years. They were split into three SES groups, and multi-group structural equation modeling (MSEM) was used. Children in the highest SES group reported eating fruit more frequently and reported more positive ASE variables than children in the lower SES groups. This was particularly true for social environmental factors, home availability of fruit and intention to eat fruit. MSEM showed that the relationships specified in the adapted ASE model were moderated by SES, as we did not find support for equal model structure across the three samples. Model modification for each SES group separately showed that the relation between home availability and fruit intake was not significant for the medium and low SES groups, and the relation between self-efficacy and intention to eat fruit was not significant for the medium SES group. Future interventions aiming at increasing fruit intake in children need to be sensitive to such SES-related differences and should in particular affect factors that may impede fruit intake in the lower SES groups.

Comparison of HIV-1 prevalence and risk factors between pregnant, non-pregnant, all women and the general population in Tanzania: implications for second-generation surveillance.

The aim of this study was to compare HIV-1 prevalence between pregnant, non-pregnant, all women and the general population (men and women) and investigate how well risk behaviours of pregnant women reflect those of all women in the general population in rural Kilimanjaro, Tanzania. A cross-sectional survey involving all individuals aged 15-44 years was conducted in Oria village between March and May of 2005. All consenting individuals were interviewed and offered HIV-1 and syphilis testing. The response proportion among women was found to be 73.7% (914/1241). Age-adjusted HIV-1 prevalence among pregnant women (n = 92) was 32.5% lower (5.4% versus 8.0%, P < 0.001) than that of all women but only 8.5% (5.4% versus 5.9%, P = 0.639) lower compared with that of the general population. HIV-1 risk factors among pregnant women were comparable to that of all women in the general population. In conclusion, pregnant women in the general population underestimate the HIV-1 magnitude among women but closely approximate that of the general population. HIV-1 risk factors are similar between pregnant and all women in the general population. Second-generation surveillance could utilize pregnant women risk behaviours to approximate that of all women in the general population.

Effect of free vitamin D(2) drops on serum 25-hydroxyvitamin D in infants with immigrant origin: a cluster randomized controlled trial.

BACKGROUND/OBJECTIVE: To study whether a free supply of vitamin D(2) drops to 6-week-old infants together with tailor-made information handouts improves the vitamin D status after 7 weeks in the intervention group compared to a control group. SUBJECTS/METHODS: In this cluster randomized controlled trial in eight child health clinics in Oslo, Norway, 66 healthy infants with Pakistani, Turkish or Somali background were included. The intervention group received daily supplementation of vitamin D drops containing 10 microg (400 IU) of ergocalciferol (vitamin D(2)) with a tailor-made information brochure about vitamin D and its sources, and instruction on how to administer the drops. They were compared to a control group receiving usual care. The principal outcome measure was increase in serum 25-hydroxyvitamin D (S-25OHD) 7 weeks later. S-25OHD was analyzed by high-performance liquid chromatography-ultraviolet-mass spectrometry. RESULTS: Total 78% (n=51) of the included infants completed the study. At follow-up, S-25OHD was significantly higher in the intervention group than in the control group (93.5 versus 72.7 nmol l(-1), P=0.03). The mean increase in S-25OHD adjusted for baseline was 28 nmol l(-1) (95% confidence interval 10.9-45.2, P=0.002) higher in the intervention group than in the control group. Among exclusively breastfed infants at baseline, S-25OHD increased by 32.3 nmol l(-1) (P=0.035) in the intervention group compared to control group. CONCLUSION: Free supply of vitamin D drops to 6-week-old infants together with tailor-made information handouts significantly improved the vitamin D status of infants with immigrant background compared to usual care.

Changes in exposure to information, communication and knowledge about AIDS among school children in Northern Tanzania, 1992-2005.

This article aims to investigate changes in primary school students' reported exposure to AIDS information and communication, and knowledge levels from 1992 to 2005. A repeated cross-sectional design was used. In 1992, a self-administered questionnaire was completed by 2,026 sixth and seventh grade students from 18 randomly selected primary schools in Arusha and Kilimanjaro regions, Tanzania. The same procedures were repeated in 2005 with a sample of 2,069 students. Mean values with 95% confidence intervals are reported. Chi-square was used to test for differences in proportions. Students in 2005 reported higher levels of exposure to information and communication from all sources than in 1992. Knowledge scores also increased, yet there was a significant decline in four variables, two of which are related to transmission and two of which are factual. An alarming decline in awareness of the condom as a preventative measure was found. Findings also indicate that myths related to transmission and infection persist. Salient sex differences remain, but the knowledge gap is narrowing. Interventions should aim to stimulate discussion in young people's social networks in order to increase overall exposure to AIDS information, communication and knowledge.

A systematic review of the evidence regarding efficacy of obesity prevention interventions among adults.

In the past, interventions aimed at reducing obesity have mainly targeted at weight loss treatment in obese adults, with limited long-term effects. With the increasing number of people being obese and being at risk for obesity, there has been a shift in focus towards prevention of obesity. We conducted a systematic review of the peer-reviewed literature on the efficacy of obesity prevention interventions in adults in order to identify effective interventions and intervention elements. Pubmed, OVID, and Web of Science databases were searched from January 1996 to June 2006. Interventions aimed at primary prevention of weight gain among adults achieved by focusing on dietary intake, physical activity or the combination of both were included. The outcome measure had to be difference in change in body mass index or body weight between the intervention and the control groups. Nine studies were included, five long-term studies (at least 1 year) and four short-term (3 months to 1 year). Seven studies evaluated an intervention that focused on a combination of diet and physical activity to prevent weight gain, one on diet only and one on physical activity only. One dietary intervention (long-term), and three combined dietary and physical activity interventions (one long-term and two short-term) produced significantly positive results at end of follow-up. The two long-term, effective interventions consisted of intensive and long-term intervention implementation, including groups sessions designed to promote behavioural changes. The current evidence of efficacy of obesity prevention interventions is based on a very small number of studies. Some studies showed a positive impact on body mass index or weight status, but there was too much heterogeneity in terms of study design, theoretical underpinning and target population to draw firm conclusions about which intervention approaches are more effective than others. More research is urgently needed to extend the body of evidence.

Sexually transmitted infections knowledge and its impact in the practice of risky sexual behaviours and HIV serostatus: results from rural Kilimanjaro, Tanzania.

OBJECTIVES: To investigate the level of knowledge of different categories of sexually transmitted infections (STIs) and their impact on practice of risky sexual behaviours and HIV transmission in rural Kilimanjaro, Tanzania. METHODS: A cross-sectional study, including all individuals aged 15-44 years living in Oria village, Kahe ward, was conducted between March and May 2005. All consenting individuals were interviewed and offered HIV testing. RESULTS: The response rate was 73.0% (1528/2093). Overall, knowledge of STIs was 38.6%. Having a casual partner (59.4%) and multiple sexual partners (50.6%) were mentioned as the most potential sources of STI. Genital ulcers and vaginal discharge were the predominant symptoms noted whereas abstinence and condom use were the preferred preventive measures. Knowledge of STI complications, including HIV transmission, was very low (22.0%) in this community. The low knowledge of STI complications was significantly associated with recent (past 4 weeks) practice of multiple sexual partners (AOR 2.4, 95% CI 1.1 to 8.7), not using condoms with casual partners (AOR, 2.7, 95% CI 1.2 to 7.5) and HIV serostatus (AOR 3.4, 95% CI 1.8 to 14.5). CONCLUSIONS: Overall STI knowledge and its link to HIV transmission was alarmingly low in this community. Knowledge of STI complications may play an important role in inducing safer sexual behaviours and hence HIV prevention. Interventions addressing HIV/STI knowledge should put more emphasis on raising awareness of complications as this may play a major role in HIV/STI prevention.

Attitudes and perceived impact of antiretroviral therapy on sexual risk behaviour among young people in Kahe, Moshi Rural District, Tanzania.

Free antiretroviral therapy (ART) has been provided through the public health system in Tanzania since 2004. The success of national ART roll out programme is premised upon collaborative efforts of health systems, communities and policy environment. However, community perceptions of ART and its implications on sexual behaviours and HIV/AIDS prevention remain largely unknown. Drawing on focus group discussions with young people, this paper examines perception about ART and the potential impact of antiretroviral therapy on risk sexual behaviour in rural Tanzania. Participants included a purposively selected sample of males and females aged 14-24 years. Results show that young people were both optimistic and concerned regarding availability of ART. Positive attitudes toward ART were associated with public health significance of therapy in managing opportunistic infections and extending lives of HIV infected persons. However, the positive outcomes of therapy were considered to be short lived, unsustainable and potentially threatening to the sexual health and wellbeing of HIV negative members in the community. ART was considered to empower infected persons to intentionally spread HIV to uninfected individuals in the community through deliberate unprotected sexual activities. The study highlights the significance of reinforcing HIV prevention while underscoring the need to provide appropriate information and increasing access to ART in rural areas of Tanzania. In conclusion, creating a therapy friendly atmosphere through information delivery is crucial in promoting social acceptability of antiretroviral therapy among youths. Efforts to improve access to antiretroviral drugs should re-emphasize prevention counselling to minimize sexual transmission of HIV.

Appreciation and implementation of a school-based intervention are associated with changes in fruit and vegetable intake in 10- to 13-year old schoolchildren--the Pro Children study.

The purpose was to investigate the degree of implementation and appreciation of a comprehensive school-randomized fruit and vegetable intervention program and to what extent these factors were associated with changes in reported fruit and vegetable intake. The study was conducted among 10- to 13-year old children exposed to the intervention during the school year 2003-04 in Norway, Spain and the Netherlands. Children, parents and teachers completed questionnaires regarding (i) the implementation of the school curriculum, (ii) parental involvement, (iii) distribution of fruit and vegetables at school, (iv) children's appreciation of the project and (v) children's intake levels. Univariate analyses of covariance and multilevel multivariate regression analyses indicated that teacher-reported level of implementation of the school curriculum and schoolchildren's appreciation of the project were important determinants of changes in intake. The results point to the importance of optimal implementation of an attractive school curriculum.

Personal, social and environmental predictors of daily fruit and vegetable intake in 11-year-old children in nine European countries.

OBJECTIVE: To investigate potential personal, social and physical environmental predictors of daily fruit intake and daily vegetable intake in 11-year-old boys and girls in nine European countries. SUBJECTS: The total sample size was 13 305 (90.4% participation rate). RESULTS: Overall, 43.2% of the children reported to eat fruit every day, 46.1% reported to eat vegetables every day. Daily fruit intake and daily vegetable intake was mainly associated with knowledge of the national recommendations, positive self-efficacy, positive liking and preference, parental modeling and demand and bringing fruit to school (odds ratio between 1.40 and 2.42, P<0.02). These factors were associated fairly consistently with daily fruit intake across all nine European countries, implying that a rather uniform intervention strategy to promote fruit can be used across Europe. For vegetables, the pattern was, however, less consistent. Differences between countries in cooking and preparing vegetables might be responsible for this larger diversity. CONCLUSIONS: This study showed that especially a combination of personal and social factors is related to daily fruit and vegetable intake in schoolchildren. This shows that a comprehensive multilevel intervention strategy based upon a series of individual and social correlates will be most promising in the promotion of daily fruit and vegetable intake in children.

Effects of a comprehensive fruit- and vegetable-promoting school-based intervention in three European countries: the Pro Children Study.

The objective of the present study was to evaluate the effects of the Pro Children intervention on schoolchildren's fruit and vegetable (FV) intake after 1 and 2 years of follow-up. The intervention combined a FV curriculum with efforts to improve FV availability at schools and at home. Effects were examined in a group-randomised trial among 1,472 10-11-year-old children from sixty-two schools in Norway, the Netherlands and Spain. FV intake was assessed by means of validated self-administered questionnaires completed before the intervention (September 2003), immediately after the first year of the intervention (May 2004) and 1 year later (May 2005). Data were analysed using multilevel linear regression analyses with age and sex as covariates. Significant intervention effects for FV intake were found at first follow-up in the total sample. The adjusted FV intake reported by the children from intervention schools was 20 % higher than FV intake reported by children from control schools. At 1 year later, a significant impact was only observed in Norway. Positive intervention effects on FV intake occurred both at school and outside school. We conclude that the Pro Children intervention is a promising means to promote European schoolchildren's FV intakes, but mainly fruit intake, in the short term. As shown in Norway, where the intervention was best implemented, the intervention might also result in longer-term effects. Further strategies need to be developed that can improve implementation, have an impact on vegetable intake and can secure sustained effects.

Status and Visions for the School Health Service as Reported by Local Health Care Workers in Northern Tanzania

Objective: The World Health Organization's (WHO) Global School Health Initiative provides a strategy to utilize schools to promote health and reduce the burden of diseases worldwide. The aim of this study was to investigate local school health work in Tanzania in relation to existing national guidelines and the WHO initiative. Methods: We intervie- wed 30 health care workers employed at 15 health institutions throughout Arusha and Kilimanjaro regions. Results: The results indicate a wide gap between the national and international guidelines for school health programs and the health workers' current practices. We found the main obstacles to providing adequate health care to be related to the burden of poverty that influences all levels of school health services; lack of clarity regarding the current official guidelines for school health services; and lack of appropriate offers for continuing education in the area of school health services. Conclusion: In order to successfully establish an integrated school health service; the working relationship between schools; health centres and the community clearly needs improvement

Food insufficiency in rural Kilimanjaro, Tanzania.

OBJECTIVES: To estimate the prevalence of reported food insufficiency associated socio-demographic factors and health indicators in rural Tanzania. DESIGN: A cross-sectional study. SETTING: A rural community in Kilimanjaro, Tanzania. SUBJECTS: Eight hundred and ninety nine individuals aged 15-36 years. A structured questionnaire was administered to collect information on socio-demographic factors, health indicators and food insufficiency. Participants were tested for HIV-1 using saliva samples. RESULTS: The prevalence of food insufficiency was 25.3% with no sex difference. After controlling for potential confounders age (Adjusted Odds Ratio [AOR] = 1.05; 95% Confidence Interval [CI]: 1.02-1.08), low education level (AOR = 4.73; CI: 1.30-17.11), being a peasant (AOR = 2.29; CI: 1.04-5.04), poor self-rated health status (AOR = 4.35; CI: 1.71-11.00) and having health problems (AOR = 2.23; CI: 1.21-4.08) were associated with food insufficiency among women but not men. In unadjusted analysis, women with food insufficiency had over twice the odds of testing HIV positive although the association did not reach statistical significance (AOR = 2.12; CI: 0.87-5.19) in adjusted analysis. CONCLUSIONS: Food insufficiency was prevalent in rural Tanzania. It was associated with sociodemographic factors and health indicators among women but not men. Our findings suggest that food insufficiency may play a role in increasing vulnerability to HIV infection particularly among women however; more research is needed to explore further this relationship.

Assessing social differences in overweight among 15- to 16-year-old ethnic Norwegians from Oslo by register data and adolescent self-reported measures of socio-economic status.

OBJECTIVE: To determine to what extent self-reported and objective data on socio-economic status (SES) are associated with overweight/obesity among 15 to 16-year-old ethnic Norwegians. DESIGN: A cross-sectional questionnaire study on health and health-related behaviors. SUBJECTS: All school children aged 15-16 years old in 2000 and 2001 in Oslo, Norway. Response rate 88% (n=7343). This article is based on the data from the 5498 ethnic Norwegians. MEASUREMENTS: Self-reported height and weight were used to measure overweight (including obesity) as defined by the International Obesity Task Force cutoffs at the nearest half-year intervals. SES was determined by register data from Statistics Norway on residential area, parental education and income and by adolescent self-reported measures on parental occupation and adolescents' educational plans. RESULTS: The prevalence of overweight/obesity was low, but higher among boys (11%) than among girls (6%). Parental education (four levels) showed the clearest inverse gradients with overweight/obesity (boys: 18, 13, 10 and 7%; girls: 11, 6, 6 and 4%). Parental education remained significantly associated with overweight/obesity when adding occupation and income to the model for the boys, whereas there were no significant associations in the final model for the girls. Overweight/obesity was associated with a lower odds ratio of planning for higher education (college/university) among boys only. CONCLUSION: For the boys, parental education was most strongly associated with overweight/obesity, and the association between overweight/obesity and educational plans appears to imply downward social mobility. The relationships between the various SES measures and overweight/obesity appeared more interrelated for the girls.

Free school fruit--sustained effect 1 year later.

This study reports the effect of a school-randomized fruit and vegetable intervention consisting of a subscription to the Norwegian School Fruit Programme at no parental cost, and the Fruit and Vegetables Make the Marks (FVMM) educational programme, both delivered in the school year of 2001-02. Nine randomly chosen schools received the intervention and 10 schools served as control schools. Participating pupils completed questionnaires at baseline (September 2001), at Follow-up 1 (May-June 2002) and at Follow-up 2 (May 2003). A total of 517 pupils (84%; mean age, 11.3 years at baseline) participated in all three surveys. At both Follow-up 1 and Follow-up 2, strong intervention effects were observed for all-day fruit and vegetable intake (effect sizes were 0.6 and 0.5 portions, respectively). The sustained effect at Follow-up 2, 1 year after the end of the intervention, can partly be explained by greater participation rates in the School Fruit Programme (standard paid subscription). We conclude that the effects observed are most likely due to the no-cost subscription and not due to the FVMM educational programme, and that providing pupils with a piece of fruit or a vegetable at school at no cost for the parents is an effective strategy to increase school children's intake of fruit and vegetables. The effect is also sustained 1 year after the end of the no-cost subscription, providing increased health benefits.

Outcome and process evaluation of a Norwegian school-randomized fruit and vegetable intervention: Fruits and Vegetables Make the Marks (FVMM).

This study reports the effect of the Fruits and Vegetables Make the Marks intervention, a school-based fruit and vegetable intervention consisting of a home economics classroom component and parental involvement and encouraged participation in the Norwegian School Fruit Programme, all delivered during the school year of 2001-02. Nine randomly chosen schools received the intervention and 10 schools served as control schools. Participating pupils completed questionnaires at baseline (September 2001), at Follow-up 1 (May-June 2002) and at Follow-up 2 (May 2003). A total of 369 pupils (69%; mean age, 11.3 years at baseline) participated in all three surveys. No effect of the intervention was found for intake of fruit and vegetables eaten at school or all day, neither at Follow-up 1 nor at Follow-up 2. On analysing the effects on potential mediators, significant differences between intervention and control groups were found for Awareness of the five-a-day recommendations only. The intervention programme was rated as very good by the teachers, and the pupils reported that they enjoyed it. However, the intervention failed to change fruit and vegetable intake, probably because it did not succeed in changing the pupils' preferences for or the accessibility of fruit and vegetables--the two strongest correlates of children's fruit and vegetable intake.

AIDS education for Tanzanian youth: a mediation analysis.

Mediation analysis is a statistical technique that can be used to identify mechanisms by which intervention programs achieve their effects. This paper presents the results of a mediation analysis of Ngao, an acquired immunodeficiency syndrome (AIDS) education program that was implemented with school children in Grades 6 and 7 in Tanzania in the mid-1990s and evaluated using a controlled, group-randomized trial. The study examined which variables mediated the effect Ngao had in regard to (i) fostering positive attitudes towards people living with AIDS and (ii) decreasing intentions to be sexually active in the near future. Data from students who participated in a baseline and 12-month follow-up survey (n = 814) were analyzed. Results indicate that increasing exposure to AIDS information and increasing knowledge about human immunodeficiency virus transmission/prevention were significant mediators of the intervention's effect on alleviating the stigma associated with people living with AIDS. Moreover, encouraging more restrictive social norms about sexual intercourse was a significant mediator of the intervention's effect on decreasing students' intentions to be sexually active in the near future. Implications for future AIDS education programs for school children in this part of Africa designed to achieve similar goals are discussed.