In order to provide the most exhaustive collection of primary data, it is imperative to gather empirical evidence from various perspectives. Thus, in scholarly research, the generally accepted levels of evidence in qualitative and quantitative research include the following notions:
- Meta-analyses and controlled studies;
- Individual experimental studies;
- Quasi-experimental studies;
- Nonexperimental studies;
- Case series and case reports;
- Expert opinion and editorials.
Each of the aforementioned levels is responsible for catalyzing changes in clinical practice. Thus, meta-analyses and systematic reviews allow for collecting and contrasting large amounts of data on the subject in order to reach a clinically appropriate consensus. The change brought by such analysis may be more generalized and eligible for the patient population. Individual experiment studies, for their part, are extremely successful in terms of observing the immediate efficiency of specific treatment interventions and implementing these changes to the target populations. Quasi- and nonexperimental studies allow for practice diagnostics from a diachronic perspective, as they do not aim at interfering with the patients’ conditions and observe natural development instead. As a result, they result in a practice change unbiased by controlled variables or researchers’ willingness to reject or conform to a hypothesis.
Case series and case reports account for a thorough investigation of the individual patients’ health and socio-cultural backgrounds. Consequently, this level of evidence is extremely helpful in terms of defining peculiarities that may affect the disease’s anamnesis and further development. Finally, expert opinions and editorials are valuable in terms of establishing the need to develop in a particular direction (Ehrich et al., 2018). Thus, expert opinion serves as a reliable tool to implement a specific change to clinical practice. It may be concluded that every level of evidence is crucial in terms of practice change introduction, as these aspects are interrelated and present a reliable hierarchy of empirical data.
Reference
Ehrich, J., Somekh, E., & Pettoello-Mantovani, M. (2018). The importance of expert opinion–based data: Lessons from the European paediatric association/union of national European paediatric societies and associations (EPA/UNEPSA) research on European child healthcare services. The Journal of Pediatrics, 195, 310-311.