What is a key limitation of expert opinion in the evidence hierarchy?

A key limitation of expert opinion in the evidence hierarchy is that it is based on personal experience and may not be generalizable. While experts may have extensive knowledge and insights drawn from their professional experience, their opinions can be subjective and influenced by individual biases. This subjectivity limits the applicability of expert opinion to broader populations or different clinical scenarios.

Expert opinions might not be supported by systematic research or data, which means they can reflect the unique context and experiences of the individual expert rather than a wider consensus or robust evidential basis. This limitation highlights the importance of relying on research and empirical evidence that undergoes rigorous evaluation, ensuring that findings are applicable to a diverse group of patients and situations.