Quality Improvement Methods
50. Theory of Constraints
a. Definition: The theory of constraints (TOC) looks at operational problems as being the result of multiple limitations in a sequence of tasks being done. In a health care setting, work is usually constrained by the capacity of the series of steps or processes to provide a particular service. One of those constraints will be the most limiting one (i.e., the "bottleneck") and relaxing that constraint is necessary for any improvement to occur. TOC provides a practical approach to improvement by identifying and eliminating limits to performance.
- Goldratt, Eliyahu M.; Jeff Cox. The Goal: A Process of Ongoing Improvement. Great Barrington, MA.: North River Press. ISBN 0-88427-061-0.
- Motwani, Jaideep, Donald Klein, and Raanan Harowitz. "The theory of constraints in services: part 2-examples from health care." Managing Service Quality: An International Journal 6.2 (1996): 30-34.
- We All Fall Down: Goldratt's Theory of Constraints for Healthcare Systems, Julie Wright and Russ King. 353 pp. Great Barrington, Mass., North River Press, 2006. ISBN: 0-88427-181-1. And see review N Engl J Med 2006; 355:218-219, July 13, 2006 by Stephen G. Pauker, M.D.
c. Example: In patient flow, TOC can be applied to increase the daily capacity of a clinic, a hospital department or an entire hospital. The steps below are followed so as to determine which element, such as the number of beds, staffing or equipment, limit the daily capacity. TOC can also be applied to administrative or clinical procedures when the throughput needs to be increased or quality improved.
1) Map the system, gather operational data and develop an understanding of current limitations and inefficiencies.
2) Identify the constraints to quantity or quality and identify the most limiting constraint.
3) Get the most out of the constraint by redesign or by or shifting part or all of the work elsewhere.
4) Support the ongoing improvement of the constraints and increase capacity which is now feasible.
5) Go back to the first step such as repeating in a PDSA cycle (see Section 28).