Explain to what extent the process for manufacturing baseballs in Problem 3.42 must be improved in order to achieve 6σ quality. 

Data in Problem 3.42

The Balston Healthcare System uses SPC charts extensively to monitor various quality indicators and improve processes at its hospitals. One of the hospitals has discovered a potential problem in hand hygiene among its nursing staff. Lack of hand hygiene can be a major cause of fatal hospital-borne infections. The Centers for Disease Control has established criteria for hand hygiene in hospitals, and the hospital suspects it is not meeting these criteria. When the CDC published the criteria for hand hygiene the first of January, the hospital began collecting data—it sampled 150 opportunities for hand hygiene each week and recorded how many times hand hygiene was actually practiced according to the CDC criteria. The data showed a deficiency in hand hygiene among the nurses in the first six weeks. In week 7, a program to improve hand hygiene among the nurses was implemented with a goal of consistently reaching a target value of meeting 90% of all hand hygiene opportunities. Following is a table showing the data for the year: 

Develop a control chart based on these data (using 3σ control limits) and explain what the chart means and the steps in a quality improvement process the SPC chart results would lead the quality management staff to take.

Transcribed Image Text:

Week 1 2 3 4 5 6 7 8 9 10 11 12 Nurses Practicing Hand Hygiene 68 83 82 84 51 58 45 46 104 74 70 95