Trending Audit Findings:   \

Ques:  I have a question on the alert and actions limits - can we set action and alert limits for Audit findings (both internal and external). I am well aware of the sheets and formula for calculation of Alert and action limit but my question is different, How can we set limits for complaint or audit findings?

Ans:  For audits, observations / corrective actions - they should be made into CAPAs, and CAPAs would then be trended as per normal CAPA trending. 

However, it should be noted that in starting trending, it's important for meaningful Alert and Action limits to be established.  The standard deviation should be developed from a lot of readings, not usually only one month's worth.  Control Charts usually require one hundred measurements to establish the standard deviation, from which the Alert and Action levels are determined, and that's what I'd recommend here.  So in most cases a trend chart's Alert and Action limits won't have a useful value until at least 100 measurements exist from which a more representative standard deviation can be calculated for the trend chart. Once established those values for Alert and Action would carry over month to month, unless the categories change substantially, or some other event requires a re-evaluation.  The re-evaluation could be part of the annual QA senior management review.

-- jel@jelincoln.com