The University Health Network 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 Network has established criteria for hand hygiene in hospitals and the hospital suspects it is not meeting these criteria. When the Network published the criteria for hand hygiene the first of January, one of the hospitals 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 Network 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.

 Week                      Nurses practicing hand hygiene

1 …………………………………………..   68

2 ………………………………………….    83

3 ………………………………………….    82

4 …………………………………………     84

5 ……………….….…………………….      51

6 …………………..…………………….      58

7 …………………….…….…………….      45

8 …………………………….….………       46

9 ……………………………………….     104

10 ………………………………………       74

11 ……………………………………….      70

12 ………………………………………..     95

Develop a control chart based on this data (using 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.