A hospital quality team uses a run chart to monitor central line-associated bloodstream infection (CLABSI) rates over 18 months. Which of the following findings on the run chart would most strongly indicate a non-random special cause improvement?
Tap an answer to reveal the correct answer, rationale and source.
Answer:
Six or more consecutive data points on the same side of the median is a standard run chart rule indicating non-random special cause variation — a signal of real process change, not chance. This is a foundational SPC rule tested on the CPHQ exam.
Source: Perla RJ, Provost LP, Murray SK. The run chart: a simple analytical tool for learning from variation in healthcare processes. BMJ Qual Saf. 2011;20(1):46-51
