Randomized Controlled Trials—Why Are They the Gold Standard?

By Nicole M. Fontenot, DNP, APRN, ACNP-BC, CCNS, CCRN-K, Nurse Scientist

When I was an undergraduate nursing student, I remember one of my nursing professors telling me that I could only cite randomized controlled trials for a paper about pressure injury prevention. I grew increasingly frustrated as I scoured the literature, looking for the "right" type of research to satisfy my professor. As I finished my assignment, I wondered, "why are randomized controlled trials so great, anyway?"
Randomized Controlled Trials (RCTs) have long been touted as the Gold Standard for healthcare and nursing research.1 RCTs are designed to randomly assign participants to either a control group (also called a "placebo" group, in some instances) or an intervention group.1 This randomization minimizes confounding factors that could affect or bias the research study's results. RCT results are more likely to reflect the study intervention's true effect.2 These types of studies can provide us with valuable information about treatments, pharmaceuticals, and nursing interventions that we can then translate into our practice. Why, then, if RCTs are so great, aren't all research studies designed this way? As great as RCTs are, they do have some drawbacks. RCTs are not always generalizable.2 The participants in a study may not reflect all genders, age groups, or ethnicities. Therefore, you cannot assume your patients will have the same outcomes. RCTs also can take a long time to complete because they usually need a large sample size. Often spanning several years of data collection and data analysis, RCTs may take a long time to provide us with answers and guidelines.3 Lastly, RCTs can be expensive because they may require support staff for data collection, costly interventions, participant recruiting and marketing, and more.2 Sometimes other research methods make more sense. Descriptive studies, qualitative research, non-randomized trials, cohort studies, and retrospective studies are all valid research methods.4 Some research areas cannot ethically use RCT methods. Take CPR as an example; we could not randomize patients in cardiac arrest to half get CPR and half to not get CPR to determine if CPR is effective or not. This study would not be ethical and would cause undue harm to half of the research participants. While other types of research do not take the place of RCTs, they can provide timely answers to our burning questions. They might be more affordable for researchers who may not have the funds for an RCT and can give some options when RCTs are not safe or ethical. And perhaps these types of studies can provide the baseline knowledge onto which RCTs can be designed for the future. Now that I am a nurse scientist, I frequently am asked, "are Randomized Controlled Trials the only types of studies I can use for my evidence-based practice initiative?" This question always takes me back to my state of mind as an undergraduate nursing student. And while I am sure my professor had great intentions for making RCTs the only type of research I could include in my paper, my answer is quite different from hers: You should use the highest quality of research you can find. If that is RCTs—awesome. If all you can obtain are descriptive studies, that's ok too. And if you can't find any research, then it's time to do your own research study—whether that is a Randomized Controlled Trial or something else.
  1. Hariton, E., & Locascio, J.J. (2018). Randomized controlled trials—the gold standard for effectiveness research. BJOG: An International Journal of Obstetrics and Gynaecology, 125(13), 1716.
  2. Akobeng, A. K. (2005). Understanding randomized controlled trials. Archives of Diseases in Childhood, 90, 840-844.
  3. Bench, S., Day, T., & Metcalfe, A. (2013). Randomized controlled trials: An introduction for nurse researchers. Nurse Researcher, 20(5).
  4. Clay, R.A. (2010). More than one way to measure. Monitor on Psychology, 41(8), 52. Retrieved on March 2, 2021, from The pitfalls of randomized controlled trials (
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