The meaning of variation to healthcare managers, clinical and health-services researchers, and individual patients

Abstract

Healthcare managers, clinical researchers and individual patients (and their physicians) manage variation differently to achieve different ends. First, managers are primarily concerned with the performance of care processes over time. Their time horizon is relatively short, and the improvements they are concerned with are pragmatic and ‘holistic.’ Their goal is to create processes that are stable and effective. The analytical techniques of statistical process control effectively reflect these concerns. Second, clinical and health-services researchers are interested in the effectiveness of care and the generalisability of findings. They seek to control variation by their study design methods. Their primary question is: ‘Does A cause B, everything else being equal?’ Consequently, randomised controlled trials and regression models are the research methods of choice. The focus of this reductionist approach is on the ‘average patient’ in the group being observed rather than the individual patient working with the individual care provider. Third, individual patients are primarily concerned with the nature and quality of their own care and clinical outcomes. They and their care providers are not primarily seeking to generalise beyond the unique individual. We propose that the gold standard for helping individual patients with chronic conditions should be longitudinal factorial design of trials with individual patients. Understanding how these three groups deal differently with variation can help appreciate these three approaches.

Interrupted Time Series Versus Statistical Process Control in Quality Improvement Projects

“…The methods depend on the aim of the measurement. 3 If the aim is to produce evidence of the effect of an intervention that will be generalized, an experimental design such as a randomized controlled trial might be appropriate. 1 If the aim is instead to measure the effect of an improvement intervention, methods that include measurements over time (time-series studies) are more appropriate.…”

“…(3) The effect of the change/improvement must be measurable. (4) The description of the implemented change/improvement must be detailed enough to replicate in other contexts.…”

Process mapping as a framework for performance improvement in emergency general surgery

“…6 Common causes of variance are predictable, expected and natural to the system. 5 Identifying common causes is challenging; however, these variables (e.g., speed and runtime of electronic health records) generally do not require change strategies. Alternatively, special causes are new and unanticipated variables that cause variance, and these causes are defects within the system that necessitate improvement (e.g., different physician management strategies for clinical presentations).…”

“…The pioneering work of Dr. Deming is epitomized by understanding and learning to manage variation. 5 Variation exists in all processes and people as well as in the outcomes that are produced in any given system. In his seminal work, he stratifies the concept of variation into common and special causes.…”

“…Alternatively, special causes are new and unanticipated variables that cause variance, and these causes are defects within the system that necessitate improvement (e.g., different physician management strategies for clinical presentations). 5,7 Process mapping in health care involves following patients through their hospital journey and documenting every interaction they have with the hospital system. The method allows providers to notice the small steps before management and discharge and identify areas of high variation and bottlenecks for future improvement.…”