After testing change on a small scale, learning from each test and refining the change through several Plan, Do, Study, Act cycles—including testing the change under varying conditions, on different shifts and with different staff—the change may be ready for implementation on a broader scale. Implementation is a permanent change to the way work is done and involves integrating change into the organization and possibly revising documents and written policies.

Testing a change before implementing it is important because it will:

• Increase the degree of belief that change will improve the work;
• Document expectations and learning;
• Build a common understanding of what "good" looks like;
• Help evaluate the costs and side effects of changes;
• Explore theories and predictions;
• Test ideas under different conditions;
• Help teams learn and adapt in real time.

Spread  is the process of taking a successful implementation process and replicating that change or package of changes in other parts of the facility or other regions.

There are many elements and roles involved in spreading a process:

• Leadership. Sets the agenda and assigns responsibility for spread.
• Set up for spread. The target population is identified and an initial strategy formulated for reaching all sites in the target population with new ideas.
• Better ideas. A description of the new ideas and evidence to "make the case" to others is developed.
• Communication. Ways to share awareness and technical information about the new ideas are determined
• Social system. Leaders consider the relationships among the people who will adopt the new ideas.
• Knowledge management. The practice of observing and spreading best methods as they emerge from the practice of the organization.
• Measurement and feedback. Collecting and using data to monitor and make adjustments to the spread procress.

Source: Institute for Health Improvement