OOS,OOT investigations

Which guidelines explains about OOS and OOT ?Plz provide PDF.

USFDA’s guidance on OOS test results requires failure investigations and other steps for Out-of-Specification (OOS) and Out-of-trend (OOT) results. While most companies are familiar with and have procedures for OOS results, this is not the case for OOT situations. The guide states: “Although the subject of this document is OOS results, much of the guidance may be useful for examining results that are out of trend”.
Managing OOT results also helps to avoid time consuming OOS results. The industry is unsure how to interpret and implement the FDA guidance.
Please refer USFDA guidance of October 2006 on Investigating Out-of-Specification (OOS) Test Results for Pharmaceutical Production .