A correlation study is used when it is necessary to assess the relationship between two or more variables. This kind of study provides information about the direction and strength of the relationship between the two data. Experimental research seeks to identify the relationship between cause and effect. This type of research implies a manipulation of a variable that is manifested by the subject, followed by the effect of the manipulation on another variable. An experimental study is more appropriate for determining the effect of a new drug because it is precisely a cause-effect relationship that needs to be analyzed.
Cross-sectional studies are studies where each patient is examined once. Using this research design, it becomes possible to describe the picture of the disease in one patient or in a population of patients. Unfortunately, such reconstructions of disease development, based on brief observation of individual disease cases, are not always correct. The main reason for errors is the construction of cause-and-effect relations that are based on impressions and the correlation of cases (Wang & Cheng, 2020). An obvious weakness is an impossibility of changing the primary examination methodology, group selection, and other aspects. Additional problems are created by the fact that participants sometimes drop out of the study for one reason or another, reducing the sample size and the amount of data collected.
Longitudinal studies are studies in which a group of people is singled out, who are observed for some time and repeatedly, at least once, their condition is assessed. The promptness and affordability of such a study, as well as greater accuracy of the results obtained, are the reasons why a longitudinal study type should be used. When conducting an experimental study, scientists are sometimes tempted to manipulate the data obtained by using random causal relationships. However, since this disadvantage is more of a subjective nature, it was decided to stick with this type of the study. As a result of the choice of this particular research design, it will be possible to avoid biases and to conclude about the lasting effect of the new drug for the treatment of ADHD in children.
Numerous twin studies demonstrate a high degree of inheritance of ADHD, as well as evidence of the predominant influence of genes on the etiological picture of the disease. Although such studies do not rule out the importance of environmental factors, they suggest that the latter interact with genetic factors in most cases. Quantitative genetic studies allow researchers to examine the extent to which genetic factors influence ADHD (Faraone & Larsson, 2019). It is also possible to identify the degree of common genetic variability in the disease and associated cognitive disorders. Molecular genetic studies will make it possible to identify specific risk factors for ADHD and provide a detailed understanding of the molecular and neurobiological mechanisms involved.
The American Psychological Association highlights several rules of the design and conduct of clinical trials of medications involving minors. To ensure that these standards are met, it is required that participants in the experiment be guaranteed the most comfortable conditions possible. To do this, it is important to teach researchers how to communicate with children and how to provide emotional support (American Psychological Association, 2017). A system of controls is required to ensure that the questionnaires used in the analysis are understandable and previously tested on children.
American Psychological Association. (2017). Ethical principles of psychologist and code of conduct. Web.
Faraone, S. V., & Larsson, H. (2019). Genetics of attention deficit hyperactivity disorder. Molecular Psychiatry, 24, 562–575. Web.
Wang, X., & Cheng, Z. (2020). Cross-sectional studies: Strengths, weaknesses, and recommendations. Chest, 158(1), 65–71. Web.