A total of 95 relevant papers were identified) [6–100]. Additional file 1 provides a summary of these papers and their contents.
Five papers were published in the 1980s, 47 papers in the 1990s, and 43 papers from 2000–2005. Thirty-four papers were published internationally, 55 regionally (i.e. within the Caribbean) and six locally as country reports. There were 58 full-text publications (51 full-text journal articles, five local reports, one book and one book chapter). And for 28 papers, only abstracts were available. Nine relevant theses were located at the libraries of The University of the West Indies.
The methodologies employed in the studies included surveys (65), retrospective reviews of case records (15), interviews (8), case-controlled studies (6), focus groups (5), secondary review of previously collected data (3), prospective autopsy study (1) and cohort study (1). Ten publications used more than one methodology.
From the research, health risk behaviours and outcomes identified could be grouped into seven main categories: substance use, high risk sexual behaviour, teenage pregnancy, STIs, including Human Immunodeficiency Virus (HIV)/AIDS, mental health, violence and delinquency, and eating behaviours and obesity.
There were 21 papers, starting from the early 1990s, which dealt primarily with substance use. There were nine full-text peer-reviewed papers; seven published only as abstracts; two country reports; two theses; and one chapter in a book.
Most papers provided prevalence data with the common indicators: 30-day prevalence and lifetime prevalence. Although papers differed methodologically, alcohol was the most commonly used substance followed by cigarettes and then marijuana. Additional file 1 summarises the general substance use [6–11] and 30-day prevalence and the life-time prevalence of substance use for selected drugs [12–28].
Risk factors for substance use
Several Caribbean studies identified the following risk factors for substance use: being male [12–15], having a family member using or supporting the adolescents' use of the substance [6, 10, 12, 14], absence of religious involvement [6, 12, 16], having lower grades at school [6, 12], having larger amounts of spending money [6, 12] and being children of professionals .
In addition, the Caribbean Youth Health Survey reported that abuse, skipping school and experiencing rage  were risk factors for smoking and alcohol use. A study done in Trinidad and Tobago, where the ethnic mix of persons of East Indian descent (Indo-Trinidadian) to African descent (Afro-Trinidadian) is about equal (this mix being similar only to Guyana as in the other countries there is a majority of persons of African origin), found that Indo-Trinidadian adolescents were more likely to have used alcohol in the last month while Afro-Trinidadian adolescents were more likely to have used marijuana [6, 17].
High risk sexual behaviour
Twenty-two papers addressing high risk sexual behaviour were identified. There were 13 full-text papers, four abstracts, three local reports and two theses. Four themes were noted in these papers: (a) studies looked at the prevalence of high-risk sexual behaviours (reported age of sexual debut, presence of multiple partners, and lack of contraceptive or condom use); (b) risk factors; (c) protective factors for initiating sexual activity; and (d) teenage pregnancy, HIV/AIDS and STIs.
Prevalence of common high-risk sexual behaviours among Caribbean adolescents
Sixty-six percent of adolescents reported that they had not had sexual intercourse . The papers reporting prevalence of high-risk sexual behaviour, including initiation of sexual activity before the age of 10 years, not using a contraceptive method, having multiple sexual partners in the past 12 months, having more than six sexual partners and participating in anal sex are presented in Additional file 1[15, 19, 22, 23, 25, 29–42].
Risk factors for early initiation of sexual activity
Of the adolescents who had early initiation of intercourse, many (38%) indicated that the initial encounter was forced. Indeed a history of physical or sexual abuse was found to be a predictor of having sexual intercourse as an adolescent [10, 22]. Additional risk factors were 'less family stability', single-parent family households, low socioeconomic status, and poor knowledge of STIs  as well as male gender, recent substance use, recent depression or attempted suicide . Higher levels of sexual activity were reported if there was little adult supervision, adolescents had no specific household chores or homework or sleeping facilities were shared . In females, increased parity and experiencing menarche at an earlier age were also associated .
Protective factors for sexual activity
Protective factors included a good relationship with parents, involvement in extracurricular activities, and attending church . Family connectedness  and attending church [9, 29, 32, 33, 45] were also protective in delaying sexual debut. Adolescents who liked school were less likely to report fear or concerns about the consequences of sexual activity as their reasons for delayed coitus. In addition, those who attended religious services as well as had married parents were significantly less likely to also cite the "lack of opportunity to have sex" as an explanation for not being sexually active . In Anguilla, the top three reasons for abstaining from sexual activity included "wanting to wait until older", "no opportunity with someone I like" and "not being emotionally ready" .
Several misconceptions about pregnancy were noted among adolescents with approximately one third being unaware that pregnancy was possible at first intercourse. Many males believed that having sex while standing prevents pregnancy, and that condoms were only for boys who have sex with more than one girl .
Fourteen papers were located which dealt with risk factors and pregnancy outcomes in adolescents. There were seven full-text publications, five abstracts and two theses. Research in this area focused on four themes: (a) the risk factors contributing to teen pregnancy; (b) the prevalence of teen pregnancy; (c) the risk and complications of teen pregnancy, and (d) repeat pregnancy among teens.
Risk factors for teen pregnancy
Four papers addressed the issue of risk factors for teen pregnancy. One conclusion arising out of these papers suggests that teens who got pregnant, themselves had teenage mothers [46–48]. These teens either lived in homes with no male authority or father figure [46, 49] or tended to live away from their parents . There was also a higher likelihood that the adolescent had been sexually active before age 16  and had never had discussions with their parents about sexuality . In 1999, it was observed that most teenage pregnancies occurred in unmarried females and, if married, the teenagers were in unstable relationships with high rates of divorce .
The prevalence of teen pregnancy
Despite the early initiation of sexual activity among teens in the Caribbean there is growing evidence of falling adolescent birth rates. For example, in Antigua and Barbuda, there was a 43% decrease in all adolescent births between the periods 1969–73 and 1994–8  and in Trinidad, a 2% decrease between 1960 and 1987 . Overall, teenage pregnancies represented 15% – 20% of all pregnancies [53, 54].
Risk and complications associated with teen pregnancy
Teen pregnancies have an increased risk of complications which include: preterm labour , operative delivery [54, 55], small for gestational age babies, prematurity and perinatal mortality [53, 54, 56], ante-partum and post-partum haemorrhage, elevated blood pressure, pre-eclampsia, eclampsia, prolonged rupture of membranes and prolonged labour . Where antenatal care for teenage pregnancies is high, the 'obstetrical performance' (as measured by antenatal and intra-partum complications) was similar to matched controls [57, 58].
Repeat pregnancy among teens
The risk predictors of one or more repeat pregnancies were common-law relationships with either the father of the first baby or another current partner, perceptions of one's socioeconomic status as very poor or poor and being a member of household where the respondent or spouse was the main wage earner. Variables that exerted a protective effect against the occurrence of one or more repeat pregnancies were: the desire to continue one's education after the birth of first child, taking action to continue education, use of contraception after first birth, being a member of a household in which the mother was the major wage earner at the time of the first birth and the absence of a current sexual relationship with their first 'baby father' .
STIs and HIV/AIDS
The area of STIs including HIV/AIDS is one of increasing interest to researchers in the field of adolescent health and much research has been carried out since 2000. Fifteen papers (nine full-text articles, three reports, two abstracts and one thesis) cover this topic.
Risk factors for STIs
Multiple partners, low frequencies of condom use in the last sexual encounter or among those with multiple sexual partners, marijuana use and having multiple sexual partners were some of the common risk factors identified for STIs [15, 19, 37, 60]. An increased risk of HIV occurred in individuals who had a history of genital ulcer disease and gonorrhoea . In different populations there are other psychocultural issues which have been identified, such as, infidelity, sex-in-exchange for resources and lack of frank discussions on sexual issues which is thought to contribute to the HIV epidemic in the region .
Factors protecting against STIs
Increased educational achievement, consistent condom use and delaying the age of sexual debut were all identified as protective factors against STIs; for every year increase in level of education, the odds of reporting STI symptoms decreased by 0.87 [37, 62]; and for every year increase in the age of first intercourse, the odds of reporting STI symptoms decreased by 0.92. Males who reported consistent condom use with steady partners were less likely to report symptoms of STIs than were inconsistent users .
The Caribbean literature identified focussed on adolescent perceptions of HIV/AIDS. Again even though not dealing with behaviours the relevant research has important implications for risk behaviours and is, therefore, included in this review. As was noted above Caribbean adolescents are aware of HIV and AIDS, with as many as 86% having heard about AIDS, and 90% knowing that HIV was sexually transmitted . Young persons 10–20 years old indicated that they were "afraid of getting AIDS" . A report on HIV infection among adolescents in Jamaica found that the mean age of diagnosis was 15.6 years . The cumulated case rate for HIV in Jamaica between 1982 and 2001 for 10–19 year olds was 10/100 000 males and 27/100 000 females. Consensual sex was the most common method of transmission in 56% of cases; in another study among adolescent attendees at an STI clinic, co-infection with HIV was noted in one percent of attendees.
One paper, which studied Jamaican street boys between the ages of 11 and 17, identified the following risk factors for HIV: an inability to obtain condoms; negative attitudes toward condom use; early age of sexual initiation; multiple sex partners; as well as drug and alcohol use. In addition, many of these boys held misconceptions about HIV/AIDS. Other issues identified included intolerance toward homosexual behaviour and physical abuse against girls .
Much of the work on HIV/AIDS has been conducted by regional organisations. Research such as KAPB (Knowledge, Attitude, Practices and Behaviour) studies of the general population has not been published in complete form internationally. These are represented in Additional file 1[65–67]. Additional information regarding sexually transmitted diseases among adolescents and young people in the Caribbean is also provided in Additional file 1[15, 19, 37, 60, 62, 68].
A total of 18 items were found: ten full-text papers, six abstracts, one report and one thesis. Papers dealt primarily with psychopathology [69, 70], attempted suicide (parasuicide) and suicide [71–80] as well as depression [81–84].
Fear of injury or death of self or loved one, sexual issues and failure at school were the major concerns of adolescents . Females were also more likely to have experienced an adolescent crisis, while male adolescents were more often diagnosed with schizophrenia. Psychosexual problems, parental conflict and hostility were the main risk factors for these psychopathologies . An increased prevalence of health compromising behaviours were noted in adolescents who experienced physical or sexual abuse and in those who had a friend or relative who had attempted suicide . Reported protective factors for these psychopathologies were avoiding parental separation, divorce or the absence of one parent .
Corresponding with international data, females had higher rates of attempted suicide [71, 72, 75, 76]. The main reason given for attempting suicide was interpersonal conflicts which included intra-familial and marital conflicts as well as lovers' quarrels. Alcohol use with prior or attempted suicide was also noted . There were ethnic differences in Trinidad where Indo-Trinidadians made more suicide attempts than Afro-Trinidadians or mixed race counterparts [72–75]. Among hospital admissions, 25% were found to be depressed and 22% had adjustment disorders . In Guyana, a similar ethnic difference was reported . In South Trinidad most patients came from rural areas and identified family instability, emotional problems, financial difficulties, peer pressure, and unemployment as additional risk factors for attempting suicide .
The most common method of attempting suicide was by ingestion of a toxic substance, mainly, herbicide (paraquat) (63%) or insecticide (organophosphates) (20%). Intake of oral medication to commit suicide was about 8% [73, 76]. The main strategies used for healing were family support and counselling [75, 76].
The only papers concerning completed suicide came from Trinidad and Tobago. Of 270 cases of completed suicide reported at the General Hospital in Port-of-Spain, Trinidad, 10% were from the 11–18 year group compared to the 19–26 year olds who had the highest number of cases (25%). The ethnic base of this sub-population had equal numbers of male patients of African and East Indian descent; however, in females, Indo-Trinidadian patients outnumbered Afro-Trinidadian patients by two to one. Lovers' quarrels, psychiatric illness and family disputes accounted for the majority of cases. Persons of Indo-Caribbean origin predominated in suicides due to lovers' quarrels or family disputes [78, 79] and persons of Afro-Caribbean origin were slightly (53% vs. 45%) more represented in persons suffering from psychiatric illnesses. Depression was the most common psychiatric illness diagnosed. The herbicide, paraquat, was the most commonly used substance in both North and South Trinidad [78–80].
Depression was twice as likely to occur in females as males (18% vs. 8%) with the highest rate of depression in the 16 to 17-year group. Attendance at a religious institution and prayer with the family was associated with a lower depression rate. Intact families had the lowest rate (12%), while the reconstituted family had the highest rate (26%). Adolescents were more likely to be depressed if there was abuse of alcohol among family members and if they attended schools which had low status ranking in terms of academic performance . There were no ethnic differences among depression cases. A review of the impact of protective factors showed that attendance at a religious institution lowered only suicidal ideation, while prayer with the family lowered both suicidal ideation and suicide attempts. Individuals with alcohol abuse in the family had higher suicidal ideation and attempts . Depression rates among adolescents ranged from 9–28%, however, these rates include the spectrum of mild to severe depression [81–84]. Psychological issues among Caribbean adolescents were also discussed)[23, 25, 72–74, 79, 80, 83, 84].
Violence and Delinquency
Fourteen papers were located under this theme. There were nine peer-reviewed full-text published papers, two theses, one book, one national report and one abstract. Sub-themes included (1) juvenile delinquency, (2) domestic violence and its impact on the adolescent, (3) injuries at the Accident & Emergency (A&E) Department and hospital, and (4) school violence.
The risk factors contributing to juvenile delinquency and school dropouts included a breakdown in family structure, violence in the home, drug use and abuse, association with gangs and economic factors  such as, barriers within the educational system, customs and culture .
Pupils whose parents were experiencing violent marital discord showed significantly higher levels of both depression and behavioural problems than those pupils not exposed to domestic violence. In addition, "children witnessing domestic violence exhibited more behavioural problems but less depressive symptomatology than adolescents" .
Violence and hospital admission
At the A&E Departments, patients under 20 years old accounted for 26% of admissions to the emergency room in Trinidad . A review of the adolescent admissions to hospital in Barbados over a 12-month period revealed that 23% were for trauma, 21% were for abortions and 7% were for drug abuse and overdose .
Violence among secondary school students
Many students had witnessed violence in the home (45%) and school (79%). Many others had personal experience – either causing harm (29%), experiencing harm themselves (20–34%) or having a family member hurt (60%) or killed (37%) [90–93]. Seventy-eight percent of students indicated that they were worried about their safety in going to and from school. Boys, older students and those with lower socioeconomic status reported higher neighbourhood violence. Boys and students from higher socioeconomic status reported higher levels of school violence . Additional statistics on violence-related activity is provided in Additional file 1[23, 25, 88, 91].
Eating Disorders and Obesity
The research yielded seven papers: three full-text publications and four other papers available only as abstracts. Papers were focused on two areas of interest: eating disorders and weight control behaviour; and body image, physical activity and obesity.
Eating disorders and weight control behaviour
In 1991, anorexia nervosa was found to be more common in the higher socio-economic group and young females seldom choose food refusal as a method of expression of weight controlling behaviour in Barbados . In another study in 2004 although 11% were clinically significant on a screening test, no students were diagnosed with bulimia on the Bulimia Diagnostic Interview (DSM III-R). An increased Body Mass Index (BMI) was associated with being terrified of becoming fat, fat-fear, dieting and exercising to lose weight. The distribution of the screening score was not affected by ethnicity or social class; however, girls of Afro-Caribbean origin expressed more concerns with respect to eating habits. In particular, it was noted that there was a sense of lack of control over food, food dominated their lives, they ate in secret and there was the urge to binge . In another study in 2002, weight-controlling behaviour was prevalent and was found to be similar across genders. This study also showed that while Caribbean adolescents reported lower levels of weight and body dissatisfaction compared to adolescents in the United States, Caribbean adolescents reported higher levels of extreme dieting behaviour such as induced vomiting and taking diet pills. More girls than boys were dissatisfied with their weight and bodies. A higher percentage of girls than boys reported that they dieted or exercised as a method to lose weight. More boys reported they had taken laxatives or diuretics and had used vomiting as a means of losing weight (all significant at p < 0.05).
Extreme weight-control behaviour was related to several psychosocial factors. Extreme dieters were more likely to report familial problems, be a below average student, have a history of physical and sexual abuse and have had a previous suicide attempt. They also reported more health compromising behaviour, such as, substance use in the past year. Boys who engaged in extreme dieting behaviour were more likely to report that they had run away in the past year and girls were more likely to report that they were sexually active .
Body image, physical activity and obesity
Two papers originated in Barbados and two in Trinidad and Tobago [97–100]. Generally these papers documented a lack of regular physical activity (about 15%) and between 4–29% being overweight or obese among adolescents. Twenty percent of females and 8% of males misclassified themselves as normal weight.
Overweight Afro-Trinidadian adolescents were more likely to be satisfied with their body size and, conversely, thin south Indo-Trinidadian adolescents were more likely to be satisfied with their body size. The majority of the sample associated normal body size with good health. However overweight was associated with wealth and 40% associated male overweight and obese silhouettes with happiness . Additional statistics on lifestyle issues are included in Additional file 1[97–100].