by - OBJECTIVE
To define the procedure for conducting investigation of Out of trend (OOT) results observed during laboratory testing of samples.
2. SCOPE
This SOP is applicable to analysis of raw material, finished product, in process samples, stability samples conducted.
3. RESPONSIBILITY
HOD’s : To follow the procedure
4. ACCOUNTABILITY
Officer QC :To notify the Head QC about the OOT result
QC & QA Head : To authorize the re-analysis
5. PROCEDURE
5.1 Out of trend result shall be determined on the basis of the data of previous batches or aberrant data observed during analysis. The result may be within the specification but it may still be out of trend for a particular test .
5.2 While performing the analysis, if any OOT or aberrant data is observed, then the analyst shall immediately inform the QC Manager who shall conduct the preliminary investigation of the OOT result.
5.3 He shall store the sample and standard preparations and any other preparations used during the analysis until the investigation is completed. He shall fill the incident report as per the attached format No……. and No…..
5.4 QC Manager of the respective section along with the analyst shall investigate reasons for OOT results by checking for analytical error. For example:
5.4.1 Whether the correct STP is followed or not.
5.4.2 Weight taken for standard and sample is as per the procedure.
5.4.3 If more than one batch has been analysed at the same time then results of the other batches shall be checked thoroughly.
5.4.4 Instrument used for analysis is within the calibration period.
5.4.5 Sonication has been carried out for the proper time as given in procedure (where applicable
5.5 During the above investigation, if the cause of OOT result is identified as laboratory error and the Head – Quality Control conclude on it, the test results shall be discarded and repeat analysis shall be carried out.
5.6 In case if the cause of OOT result is not identified as laboratory error then reanalysis shall be carried out to confirm the OOT results. The same shall be informed to the Production department and Quality Assurance.
5.7 The analyst shall record the reanalysis results in the worksheet.
5.8 The same analyst shall repeat the test with fresh sample and if required fresh standard preparation with due care to omit the errors identified.
5.9 If the retest results are now within the trend and comparable to the data of previous batches, then analyst shall report the results obtained during the second analysis and OOT investigation shall be disposed after thorough investigation of the OOT result during initial analysis.
5.10 If the cause of OOT results is not identified, and if results of re-analysis are same as the previous analysis then the results obtained during the first analysis shall be reported.
5.11 If the test result is out of trend, it shall be concluded that the material/product is not meeting the trends.
5.12 Head – Quality Control shall review the OOT results and forward the same to QA and Production for investigation and to prevent the recurrence of such incidents in the further batches.
5.13 Methodology apply 3 sigma approach
5.13.1 A minimum of 25 – 30 batches data shall be compiled for fixing the Trend range.
5.13.2 Results that shall be obtained from the 25 batches tabulated, average value,
minimum and maximum values are noted.
5.13.3 Standard deviation will be calculated for these 25 batches. Excel spread sheet
shall be used for Standard deviation calculation.
5.13.4 Standard deviation will be multiplied by 3 to get the 3 sigma (3) value.
5.13.5 Determine the alert limit expressed the formulas:
Alert Limit = Average + (2 x sigma)
Where sigma = standard deviation
5.13.6 Determine the action limit expressed the formulas:
Alert Limit = Average + (3 x sigma)
5.13.7 Where sigma = standard deviation
5.13.8 Maximum limit will be arrived by adding the 3 1 value to the Average value of
25 batches.
5.13.9 Minimum limit will be arrived by subtracting the 3 1 value from the Average
value of 25 batches. Minimum value may come in negative also at times.
5.13.10 The above maximum and minimum limits in 4.1.5 and 4.1.6 shall be taken as the Trend range for upper and lower limits.
5.13.11 Any value that shall be out of this range will be considered as Out of Trend
(OOT) value or Outlier value.
5.13.12 Wherever specification has only Not more than, then only Maximum limit for
trend can be considered. Minimum limit should be excluded.
5.13.13 Wherever specification has range then both the Maximum and Minimum limits for trend should be considered
6. TRAINING
Trainer : Head – Quality Assurance
Trainees: Staff of all the departments
7. DISTRIBUTION
Master Copy : Quality Assurance
Controlled Copy : Quality Assurance
8. REFERENCES
In-house
9. ABBREVIATION
| Abbreviation | Extended Form |
| EG | Engineering |
| SOP | Standard Operating Procedure |
| QA | Quality Assurance |
| WH | Warehouse |
| NA | Not Applicable |
| MB | Microbiology |
10. REVISION HISTORY OF CHANGE
| Sr. No. | Date | Revision Details | Revision No. |
| 1 | NA | New SOP | 00 |
