Rethinking the “Evidence Pyramid”: A shift From Positivism to Pragmatism

Abstract

The evidence pyramid ranks study designs by their reliability in establishing causal relationships, with systematic reviews and RCTs at the top due to their ability to minimize bias. However, these studies may have limited external validity, as they often use controlled environments that don't reflect real-world conditions. Observational and quasi-experimental studies offer better external validity but have lower internal validity. The pyramid's structure is based on a positivist paradigm, which emphasizes on the objective truth and empirical methods. However, newer research methodologies recognize the complexity of real-world data and promote social justice and empowerment. The evidence pyramid's overfocus on internal validity may underappreciate external validity, and it often overlooks the importance of qualitative research. With increasing importance of value-based medicine, it is imperative to consider the subjective experiences of patients in informing policies and practices. To address these issues, we have proposed the Evidence Pie model, where all study designs contribute to evidence, with quality of the evidence being determined by rigor rather than design type. This simplistic, single-layered model aims to integrate diverse evidence types for more practical, context-sensitive decision-making.