The Introduction may be variously labeled as Objectives, Aim, Purpose, or Background, or it may have no heading at all. In the Introduction, the authors describe the magnitude of the problem, and state why it is worthy of research.
The Introduction frequently includes a literature review in which previous research is described, and the knowledge gaps identified.
At the end of the Introduction, a formal thesis statement or hypothesis may be provided, or it may only be implied.
⇒In the sample article by Warren, et al., what were the three stated aims of the study?
The Methods section includes a description of the study design, the study subjects, the time frame of the study, the setting in which the study was conducted, and the statistical analysis used in the study. The purpose of this section is to describe the methodology in sufficient detail such that it could theoretically be used by another group of researchers to replicate the study. The biomedical literature is replete with examples of reports by researchers who have attempted to repeat a previous study, only to obtain different results. Since no study can exactly replicate another, the challenge for the reader is to determine how the two studies are different, and how that difference may have impacted the results.
Study designs can vary widely from straightforward basic science experiments, to qualitative studies using interviews, questionnaires, or surveys, to very costly and complex cohort studies or clinical trials. The method of data analysis used will be dictated by the study design chosen.
⇒ What study design was employed in the study conducted by Warren, et al.?
Studies involving humans must state how the subjects were recruited, and the criteria used to include or exclude individual participants. They must also include a statement indicating that permission for the study was obtained from the Institutional Review Board (IRB), or equivalent ethics board, of the institution of the lead investigator. For studies involving non-human subjects, the characteristics (species, strain, age, sex, etc.,) of the animal or organism used must be described.
⇒How were the subjects in the Warren, et al. study recruited? What is the name of the body that granted ethical approval for the study?