Observational studies are essential for evaluating the effectiveness of healthcare interventions. While randomized controlled trials (RCTs) are often considered the gold standard, they have limitations that make them sometimes unnecessary, inappropriate, impossible, or inadequate. Observational methods, such as cohort and case-control studies, complement RCTs by addressing areas where RCTs cannot reach, and by helping to design and interpret RCT results accurately. RCTs may be unnecessary when interventions have clear, dramatic effects with minimal confounding factors. They may be inappropriate when evaluating rare adverse outcomes, long-term effects, or interventions where patient preferences and participation are crucial. RCTs may also be impossible due to ethical, political, or legal barriers, or due to the scale of the task. Additionally, RCTs often have low external validity, meaning their results may not generalize well to real-world settings. Observational studies are needed to evaluate interventions that are difficult to study through RCTs, such as those involving patient preferences, long-term outcomes, or complex healthcare systems. They also provide valuable data on the effectiveness of interventions in real-world settings, which is crucial for healthcare policy and practice. The false dichotomy between RCTs and observational studies should be replaced with recognition of their complementary roles. Both methods have strengths and weaknesses, and researchers should strive for scientific rigor regardless of the method used. Observational studies can provide important insights that RCTs may miss, and they are often more practical and feasible in many healthcare contexts. Therefore, a balanced approach that incorporates both RCTs and observational studies is necessary for a comprehensive evaluation of healthcare interventions.Observational studies are essential for evaluating the effectiveness of healthcare interventions. While randomized controlled trials (RCTs) are often considered the gold standard, they have limitations that make them sometimes unnecessary, inappropriate, impossible, or inadequate. Observational methods, such as cohort and case-control studies, complement RCTs by addressing areas where RCTs cannot reach, and by helping to design and interpret RCT results accurately. RCTs may be unnecessary when interventions have clear, dramatic effects with minimal confounding factors. They may be inappropriate when evaluating rare adverse outcomes, long-term effects, or interventions where patient preferences and participation are crucial. RCTs may also be impossible due to ethical, political, or legal barriers, or due to the scale of the task. Additionally, RCTs often have low external validity, meaning their results may not generalize well to real-world settings. Observational studies are needed to evaluate interventions that are difficult to study through RCTs, such as those involving patient preferences, long-term outcomes, or complex healthcare systems. They also provide valuable data on the effectiveness of interventions in real-world settings, which is crucial for healthcare policy and practice. The false dichotomy between RCTs and observational studies should be replaced with recognition of their complementary roles. Both methods have strengths and weaknesses, and researchers should strive for scientific rigor regardless of the method used. Observational studies can provide important insights that RCTs may miss, and they are often more practical and feasible in many healthcare contexts. Therefore, a balanced approach that incorporates both RCTs and observational studies is necessary for a comprehensive evaluation of healthcare interventions.