Article

Agus, Ashley and McKay, Michael and Cole, Jonathan and Doherty, Paul and Foxcroft, David and Harvey, Séamus and Murphy, Lynn and Percy, Andrew and Sumnall, Harry (2019) Cost-effectiveness of a combined classroom curriculum and parental intervention: economic evaluation of data from the Steps Towards Alcohol Misuse Prevention Programme cluster randomised controlled trial. BMJ Open, 9, (7), e027951.

Higgins, Kathryn and McLaughlin, Aisling and Perra, Oliver and McCartan, Claire and McCann, Mark and Percy, Andrew and Jordan, Julie-Ann (2018) The Belfast Youth Development Study (BYDS): A prospective cohort study of the initiation, persistence and desistance of substance use from adolescence to adulthood in Northern Ireland. PLoS ONE, 13, (5), e0195192. https://doi.org/10.1371/journal.pone.0195192.

Higgins, Kathryn and Percy, Andrew and McCrystal, Patrick (2004) Secular trends in substance use: the conflict and young people in Northern Ireland. Journal of Social Issues, 60, (3), pp. 485-506. https://doi.org/10.1111/j.0022-4537.2004.00368.x.

McAloney, Kareena and McCrystal, Patrick and Percy, Andrew (2010) Sex, drugs and STDs: Preliminary findings from the Belfast Youth Development Study. Drugs: Education, Prevention, and Policy, 17, (4), pp. 443-453. https://doi.org/10.3109/09687630903074826.

McAloney, Kareena and McCrystal, Patrick and Percy, Andrew and McCartan, Claire (2009) Damaged youth: Prevalence of community violence exposure and implications for adolescent well-being in a post conflict society. Journal of Community Psychology, 37, (5), pp. 635-648. https://doi.org/10.1002/jcop.20322.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew (2007) Substance use behaviours of young people with a moderate learning disability: a longitudinal analysis. American Journal of Drug and Alcohol Abuse, 33, (1), pp. 155-161. https://doi.org/10.1080/00952990601091143.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew (2005) Drug use amongst 12- and 13-year-olds attending emotional and behavioural difficulty units in Belfast. Emotional and Behavioural Difficulties, 10, (3), pp. 203-218. https://www.researchgate.net/deref/http%3A%2F%2Fdx.doi.org%2F10.1080%2F13632750601135907.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew (2007) Exclusion and marginalisation in adolescence: the experience of school exclusion on drug use and antisocial behaviour. Journal of Youth Studies, 10, (1), pp. 35-54. https://doi.org/10.1080/13676260701196103.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew (2005) Substance abuse among 12 and 13-year-old young people in Belfast at high risk of developing problem drug use. Child Care in Practice, 11, (3), pp. 313-321. https://www.researchgate.net/deref/http%3A%2F%2Fdx.doi.org%2F10.1080%2F13575270500151854.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew (2006) School exclusion drug use and delinquency in adolescence. Journal of Adolescence, 29, (5), pp. 829-836. https://doi.org/10.1016/j.adolescence.2006.05.006.

McCrystal, Patrick and Higgins, Kathryn and Percy, Andrew and Thornton, Maeve (2005) Adolescent substance abuse among young people excluded from school in Belfast. Drugs: Education, Prevention and Policy, 12, (2), pp. 101-112. https://doi.org/10.1080/09687630512331323503.

McCrystal, Patrick and Percy, Andrew (2010) Patterns of substance use among young people attending colleges of further education in Northern Ireland. Drugs: Education Prevention and Policy, 18, (1), pp. 69-76. 10.3109/09687630903505501.

McCrystal, Patrick and Percy, Andrew (2009) A profile of adolescent cocaine use in Northern Ireland. International Journal of Drug Policy, 20, (4), pp. 357-364. https://doi.org/10.1016/j.drugpo.2008.09.005.

McCrystal, Patrick and Percy, Andrew (2009) Factors associated with teenage ecstasy use. Drugs: Education Prevention and Policy, 10, (17), pp. 507-527. DOI: 10.1080/09687630902810691.

McCrystal, Patrick and Percy, Andrew and Higgins, Kathryn (2007) The cost of drug use in adolescence: Young people, money and substance abuse. Drugs: Education, Prevention and Policy, 14, (1), pp. 19-28. https://doi.org/10.1080/09687630600832641.

McCrystal, Patrick and Percy, Andrew and Higgins, Kathryn (2008) Substance use among young people living in residential state care. Child Care in Practice, 14, (2), pp. 181-192. https://doi.org/10.1080/13575270701868819.

McCrystal, Patrick and Percy, Andrew and Higgins, Kathryn (2006) Drug use patterns and behaviours of young people at an increased risk of drug use during adolescence. International Journal of Drug Policy, 17, (5), pp. 393-401. https://doi.org/10.1016/j.drugpo.2006.05.007.

McCrystal, Patrick and Percy, Andrew and Higgins, Kathryn (2007) Frequent cannabis use among 14/15 years old in Northern Ireland. Drug and Alcohol Dependence, 88, (1), pp. 19-27. https://doi.org/10.1016/j.drugalcdep.2006.09.007.

McCrystal, Patrick and Percy, Andrew and Higgins, Kathryn (2007) Drug use amongst young people attending emotional and behavioural difficulty units during adolescence: a longitudinal analysis. Emotional and Behavioural Difficulties, 12, (1), pp. 49-68. https://doi.org/10.1080/13632750601135907.

McKay, Michael and Agus, Ashley and Cole, Jonathan and Doherty, Paul and Foxcroft, David and Harvey, Séamus and Murphy, Lynn and Percy, Andrew and Sumnall, Harry (2018) Steps Towards Alcohol Misuse Prevention Programme (STAMPP): a school-based and community-based cluster randomised controlled trial. BMJ Open, 8, (3), e019722.

McKay, Michael T and Percy, Andrew and Cole, Jon C (2013) Present orientation, future orientation and alcohol use in Northern Irish adolescents. Addiction Research & Theory, 21, (1), pp. 43-51. https://doi.org/10.3109/16066359.2012.685120.

McKay, Michael T and Percy, Andrew and Cole, Jon C (2012) Consideration of future consequences and alcohol use among Northern Irish adolescents. Journal of Substance Use, 18, (5), pp. 377-391. 10.3109/14659891.2012.685793.

McKay, Michael T and Percy, Andrew and Goudie, Andrew J and Sumnall, Harry and Cole, Jon C (2012) The temporal focus scale: factor structure and association with alcohol use in a sample of Northern Irish school children. Journal of Adolescence, 35, (5), pp. 1361-1368. doi: 10.1016/j.adolescence.2012.05.006.

McKay, Michael T and Perry, John L and Cole, Jon C and Percy, Andrew and Sumnall, Harry R (2021) One rule for one, and a different rule for another: The case of the Parental Rules about Alcohol Questionnaire. Drug and Alcohol Dependence, 225, p. 108824. https://doi.org/10.1016/j.drugalcdep.2021.108824.

McKay, Michael T and Sumnall, Harry and Cole, Jon C and Percy, Andrew (2012) Self-esteem and self-efficacy: associations with alcohol consumption in a sample of adolescents in Northern Ireland. Drugs: Education Prevention and Policy, 19, (1), pp. 72-80. https://doi.org/10.3109/09687637.2011.579585.

Padgett, R Noah and Andretta, James R and Cole, Jon C and Percy, Andrew and Sumnall, Harry R and McKay, Michael T (2021) Intervention impact on alcohol use, alcohol harms, and a combination of both: A latent class, secondary analysis of results from a randomized controlled trial. Drug and Alcohol Dependence, 227, p. 108944. https://doi.org/10.1016/j.drugalcdep.2021.108944.

Percy, Andrew (2008) Moderate adolescent drug use and the development of substance use self-regulation. International Journal of Behavioural Development, 32, (5), pp. 451-458. https://doi.org/10.1177/0165025408093664.

Percy, Andrew and Agus, Ashley and Cole, Jon and Doherty, Paul and Foxcroft, David and Harvey, Séamus and McKay, Michael and Murphy, Lynn and Sumnall, Harry (2019) Recanting of previous reports of alcohol consumption within a large-scale clustered randomised control trial. Prevention Science, 20, (6), pp. 844-851.

Percy, Andrew and Healy, Colm and Cole, Jon C and Robinson, Gareth and Sumnall, Harry and McKay, Michael T (2025) A network analysis of alcohol-related harms: an exploratory study in United Kingdom adolescents. Drug and Alcohol Dependence, 271, 112658. https://doi.org/10.1016/j.drugalcdep.2025.112658.

Percy, Andrew and Iwaniec, Dorota (2007) The validity of a latent class typology of adolescent drinking patterns. Irish Journal of Psychological Medicine, 24, (1), pp. 13-18. https://doi.org/10.1017/s0790966700010089.

Percy, Andrew and MdAlister, Siobhan and Higgins, Kathryn and McCrystal, Patrick and Thornton, Maeve (2005) Response consistency in young adolescents' drug use self-reports: a recanting rate analysis. Addiction, 100, (2), pp. 189-196. https://doi.org/10.1111/j.1360-0443.2004.00943.x.

Percy, Andrew and Padgett, R Noah and McKay, Michael T and Cole, Jon C and Burkhart, Gregor and Brennan, Chloe and Sumnall, Harry R (2024) Disentangling the temporal relationship between alcohol-related attitudes and heavy episodic drinking in adolescents within a randomized controlled trial. Addiction, 120, (4), pp. 645-654. https://doi.org/10.1111/add.16721.

Percy, Andrew and Thornton, Maeve and McCrystal, Patrick (2008) The extent and nature of family alcohol and drug use: findings from the Belfast youth development study. Child Abuse Review, 17, (6), pp. 371-386. /10.1002/car.1046.

Sumnall, Harry and Percy, Andrew and Cole, Jon C and Murphy, Lynn and Foxcroft, David (2017) Steps towards alcohol misuse prevention programme (STAMPP): a school and community based cluster randomised controlled trial. Public Health Research, 5, (2),

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Percy, Andrew and Wilson, Joanne and McCartan, Claire and McCrystal, Patrick (2011) Teenage drinking cultures. York: Joseph Rowntree Foundation.