Adolescent mental health problems, suicidality and seeking help from general practice: A cross-sectional study (Northern Ireland Schools and Wellbeing study).

•Unlike other studies we have been able to utilise a wide range of variables, incorporating as we have, linked school administrative data (with measures of student socioeconomic circumstances, attendance and academic performance) and self-reported mental health and family life.•Rates of poor mental health and suicidality among Northern Ireland adolescents are high especially for females and those stating a minority religious or atheist background.•Our findings suggest that social inequalities may matter much less than the family environment in determining mental health problems and the likelihood of trusting primary care doctors.•Of crucial importance, young people most at risk of poor mental health may be the least likely to seek help.