Modric T, Zenic N, Sekulic D Substance use and misuse among 17- to 18-year-old Croatian adolescents: correlation with scholastic variables and sport factors. Subst Use Misuse. 2011;46(10):1328-34. doi: 10.3109/10826084.2011.579677. Epub 2011 May 25.
Sekulic D, Ostojic M, Ostojic Z, Hajdarevic B, Ostojic L Substance abuse prevalence and its relation to scholastic achievement and sport factors: an analysis among adolescents of the Herzegovina-Neretva Canton in Bosnia and Herzegovina. BMC Public Health. 2012 Apr 5;12:274. doi: 10.1186/1471-2458-12-274.
Zenic N, Ostojic L, Sisic N, Pojskic H, Peric M, Uljevic O, Sekulic D Examination of the community-specific prevalence of and factors associated with substance use and misuse among Rural and Urban adolescents: a cross-sectional analysis in Bosnia and Herzegovina. BMJ Open. 2015 Nov 6;5(11):e009446. doi: 10.1136/bmjopen-2015-009446.
Zenic N, Terzic A, Rodek J, Spasic M, Sekulic D Gender-Specific Analyses of the Prevalence and Factors Associated with Substance Use and Misuse among Bosniak Adolescents. Int J Environ Res Public Health. 2015 Jun 10;12(6):6626-40. doi: 10.3390/ijerph120606626.
Prospective Analysis of the Factors Associated With Substance Use and Misuse in Adolescents
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
