Guided Notes
Trends, Run Charts & Control Charts
Track performance over time — run charts, statistical process control (SPC), common vs special cause variation, control limits and rules for detecting real change.
Why time matters
Slide 1 / 5Comparing just two numbers (last month vs this month) is misleading — every process varies naturally. Quality improvement uses charts over time to answer: 'Is this process stable? Did our change make a real difference?' • Run chart: data over time with a median line. • Control chart (SPC): adds statistically calculated control limits.