Follow
Definition of OOS and OOT
Out of specification (OOS) is defined as a result that falls outside the predetermined specifications or established acceptance criteria set by the manufacturer and/or the laboratory. In simple terms, the result of a stability test conducted by a Quality Analyst (QA) should always adhere to the previously established specifications or criteria. The Quality Control (QC) declares the result as OOS if it doesn’t comply or agree with the given test result criteria. Similarly, out of trend (OOT) is defined as a result that falls outside the trend. QC compares the result of the current test with a set of previous results to check with the on-going trend.
Reason for OOS
A. Laboratory Related (Testing Error) 00S
i. Method of Analysis
ii. Non- Calibrated Instruments Used
iii. Calculation Error
iv. Analyst Error
v. Instruments Failure
B. Process Related 00S
i. Operator Error
ii. Equipment Error
iii. Deviation from Validated Procedure
iv. Quality of RM/Intermediates Used
v. In-process Control During Manufacturing
C. Sample Homogeneity (Sampling Error & Handling) 00S
i. Sampling Error
ii. Handling of Sample
iii. Pooling of Sample
Phase of Investigation of 00S as per MHRA
1 Phase I Investigation – Laboratory Investigation
Phase IA: Primary Laboratory Investigation
Phase IB: Extended Laboratory Investigation
2 Phase II Investigation – Manufacturing Investigation
3 Phage III Investigation – Extended Manufacturing Investigation
Phase IA Investigation
This phase of investigation are for obvious error such as calculation or power outage, testing errors such as
spillages or incorrect setting of equipment parameters. It is expected that these issues are trended even if a
laboratory investigation lb or II was not raised.
Phase IB Investigation
This is an initial investigation conducted by the analyst and supervisor using the laboratory investigation
checklist covering the pertinent areas for investigation.
Phase II Investigation
This phase of investigation is conducted when the phase I investigations did not reveal an assignable laboratory
error. Phase II investigations are driven by written and approved instructions against hypothesis and should
always commence with a manufacturing investigation to determine whether there was a possible
manufacturing root cause.
Phase III Investigation
If the batch is rejected there still needs to be an investigation to determine whether other batches or products
are affected and to identify and implement corrective and preventative actions
