Addressing unwarranted variations in colorectal cancer outcomes: a conceptual approach.

In the clinical setting, the term 'unwarranted variation' refers to variations in patient outcomes that cannot be explained by the patient's underlying illness or medical needs, or the dictates of evidence-based medicine. These types of variations persist even after adjusting for patient-specific factors. Unwarranted variation depends on a complex mix of disparities, including inequalities in access to appropriate care in a wide variety of geographical and cultural settings, in the uptake and application of clinical knowledge, in the prioritization and allocation of resources, and differences in organizational and professional culture. Nevertheless, unwarranted variation has been inexorably linked with clinical practice. Thus, awareness of the antecedents of unwarranted variations in clinical practice is strategically important. In this Perspective, we discuss these antecedents in colorectal cancer clinical care pathways with an emphasis upon the multidisciplinary team (MDT), and suggest pragmatic steps that could be taken to address latent unwarranted variation.