Evidence-based decision-making necessary for efficient work enables practitioners to search and explore different studies formats, such as cohort or randomized controlled trials. The method determines the scope of participants, the hypotheses formulation, possible outcomes, and even ethical considerations (Wang & Kattan, 2020). A well-prepared practitioner should obtain theoretical knowledge about all research types to distinct them and use them for gathering information in professional circumstances. This paper aims to discuss, compare, and characterize cohort studies and randomized controlled trial formats.
The cohort study is a valuable method for healthcare research because it analyzes several hypotheses and compares the outcomes simultaneously. Indeed, multiple samples (cohorts) are followed longitudinally to reveal the results of interventions (Teague et al., 2018). Another method selected for this assignment is the randomized controlled trial (RCT) which is based on dividing participants into groups without considering any specific factors. In such studies, half receive the intervention to be tested, while the rest get alternative treatment (Naidoo et al., 2020). RCTs are helpful when biases and other influences on a result must be minimized, and it allows to study and measure specific actions or products.
The fundamental difference between the cohort study method and RCT is how the sampling is performed. The former requires considering the participants’ characteristics to form groups and study intervention, and, in contrast, the randomized format makes researchers eliminate any individualized factors from the equation (Naidoo et al., 2020). Another significant distinction is the timing because cohort studies require to be conducted for a prolonged period to retrieve sufficient evidence to make conclusions and observe the interventions’ results (Thampy et al., 2019). RCTs tend to be shorter because there are fewer factors to consider, and only one specific activity is being analyzed.
The cohort study tends to be related to extensive epidemiological research because interventions require participants with diverse conditions to be involved and observed for an extended period. The massive advantage of such a method is that it results in a broad scope of data that calculates risk percentage and incidence. Furthermore, multiple factors or interventions can be studied simultaneously on diverse populations and provide a sufficient foundation for further research (Wang & Kattan, 2020). Disadvantages of a cohort method are the time and expenses it requires and the impossibility of establishing causal effects of an intervention.
Correlational studies are conducted to reveal the relationship between the identified variables without active control or manipulation by researchers. It can be characterized through specific methods such as observation and survey and the expected correlation-based results (Rezigalla, 2020). Moreover, the research does not provide evidence for cause and effect, yet the conclusions tend to contain significant statistical data about the variables (Rezigalla, 2020). Correlational design can be selected for quantitative studies where the goal of identifying the relationship between variables does not require direct intervention.
A research pyramid is a valuable tool for healthcare professionals to select the right design applicable to the desired outcomes. The scheme levels the evidence-based on its weight for decision-making and can be used to identify if the results are worth considering (Thampy et al., 2019). The cohort study design is in the middle of the research pyramid, meaning that the quality of conclusions is not the highest, yet sufficient for gathering information for further decision-making.
All types of research are valuable for evidence-based decisions in nursing, and a practitioner must be able to identify and select them according to their needs. The cohort study design is necessary for retrieving the information about the longitudinal following of specific populations. The RCT type provides sufficient data about certain interventions and eliminates the biases that weaken the conclusions. The research pyramid is a tool to select the study to conduct or explore based on the strength of its evidence.