Evidence-informed person-centred health care (part II): are 'cognitive biases plus' underlying the EBM paradigm responsible for undermining the quality of evidence?

Introduction: Recently, some leaders of the evidence-based medicine (EBM) movement drew attention to the "unintended" negative consequences associated with EBM. The term 'cognitive biases plus' was introduced in part I to encompass cognitive biases, conflicts of interests, fallacies and certain behaviours.

Hypothesis: 'Cognitive biases plus' in those closely involved in creating and promoting the EBM paradigm are responsible for their (1) inability to anticipate and then recognize flaws in the tenets of EBM; (2) discounting alternative views; and (3) delaying reform.

Methods: A narrative review style was used, with methods as in part I.

Appraisal of literature: Over the past two decades there has been mounting qualitative and quantitative methodological evidence to suggest that the faith placed in (1) the EBM hierarchy with randomized controlled trials and systematic reviews at the summit; (2) the reliability of biostatistical methods to quantitate data; and (3) the primacy of sources of pre-appraised evidence, is seriously misplaced. Consequently, the evidence that informs person-centred care is compromised.

Discussion: Arguments focusing on 'cognitive biases plus' are offered to support our hypothesis. To the best of our knowledge, EBM proponents have not provided an explanation.

Conclusions: Reform is urgently needed to minimize continuing risks to patients. If our hypothesis is correct, then in addition to the suggestions made in part I, deficiencies in the paradigm must be corrected. Meaningful solutions are only possible if the biases of scientific inbreeding and groupthink are minimized by collaboration between EBM leaders and those who have been sounding warning bells.