CBIC Certified in Infection Control (CIC) Practice Exam

Time is plotted on the horizontal axis. In a control chart, observations are ordered over time (or sequence), so placing time along the horizontal axis allows you to see how the process changes as time goes by, making it easier to spot trends, drifts, or shifts. The vertical axis displays the value of the statistic you're tracking (such as a defect rate or mean). The central line is the process average, and the upper and lower control limits are horizontal lines that define the expected range of variation.