In a groundbreaking study published in the BMJ on December 28, 2023, a team of researchers led by Bahareh Rasouli has introduced a novel approach to enhance the accuracy and reliability of observational comparative effectiveness research. The study, titled “Combining high quality data with rigorous methods: emulation of a target trial using electronic health records and a nested case-control design,” addresses the critical challenge of bias in large cohort studies that typically rely on electronic health records.
This innovative method is poised to revolutionize how researchers conduct observational studies, particularly in the realm of healthcare.Â
The traditional approach in large cohort studies often involves the use of electronic health records without validating key variables or collecting additional data. This practice, while convenient, has been prone to various biases, leading to potential inaccuracies in research findings.
Rasouli and her team’s method, which employs a case-control design, allows for the validation, supplementation, or collection of additional data on key measurements in a much smaller sample compared to the entire cohort. This approach significantly reduces the potential for bias, making the findings more reliable and applicable in real-world settings.Â
The study underscores the importance of randomized controlled trials (RCTs) as the ideal design for comparative effectiveness research. However, RCTs are often costly, lengthy, and sometimes unethical or infeasible.
This reality has increased interest in using observational studies, such as those conducted using data from electronic health records and administrative datasets, to inform clinical decision-making. The analysis of observational data requires careful consideration of possible biases, including confounding, selection bias, and measurement error. The methods and tools proposed by Rasouli and colleagues are essential in minimizing these biases.Â
One of the key innovations in their approach is the emulation of a target trial using a nested case-control design. This method combines the benefits of measure validation in nested case-control designs with the strengths of target trial emulation, effectively reducing bias. The researchers provide a detailed guideline, an analytical program, and results of a clinical example to demonstrate the application of their method.Â
The clinical example used in the study involves the emulation of a target trial to estimate the effect of starting statin treatment on the prevention of myocardial infarction. The researchers developed a detailed protocol of a target trial and emulated this trial under a nested case-control design using electronic health record data. This approach allowed them to validate outcome status (cases and non-cases) using manual review of medical records, which would not be practical to do on the entire cohort.Â
The findings of this study have significant implications for the future of medical research, particularly in the field of observational studies. By providing a more reliable method for conducting these studies, the research community can ensure that the findings are more accurate and applicable to clinical practice. This advancement is a critical step forward in improving patient care and making informed decisions based on robust and reliable research data.Â
In conclusion, the study by Rasouli and her team marks a significant milestone in medical research methodology. Their innovative approach to emulating a target trial using electronic health records and a nested case-control design offers a promising solution to the longstanding issue of bias in observational studies. This method is expected to pave the way for more accurate, reliable, and applicable research findings, ultimately enhancing the quality of healthcare delivery and patient outcomes.Â
Journal Reference Â
Rasouli, B., Chubak, J., Floyd, J. S., Psaty, B. M., Nguyen, M., Walker, R. L., … Danaei, G. (2023). Combining high quality data with rigorous methods: emulation of a target trial using electronic health records and a nested case-control design. Retrieved from https://www.bmj.com/content/383/bmj-2022-072346Â
