DQM Check for RPD and ABS DIFF

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EQuIS 7  >>  Professional > Modules > DQM > DQM Checks >

DQM Check for RPD and ABS DIFF

Check for Relative Percent Difference (RPD) and Absolute Difference (run independently) values for field duplicate sample results that fall outside Quality Control (QC) limits.

 

It is important that RT_MATRIX.MEDIUM_CODE be populated for this check to work properly. Note that DT_RESULT_QC is not used for this check.

 

Check name is EarthSoft.DQM.RPD_Abs_Diff_Field = Field Dup RPD / ABS DIFF.

 

This check uses the reportable_result, result_type_code and test_batch_type parameters from Global Parameters. There are 12 other parameters:

abs_diff_multiplier – Multiplier used with detection limit to determine when to calculate and check the Absolute Difference as described in the FIELD DUPLICATE ABS DIFF rule below. Defaults to 5.

abs_diff_multiplier_other – Multiplier for other samples used with detection limit to check the Absolute Difference for the FIELD DUPLICATE ABS DIFF rule as described below. Defaults to 1.

abs_diff_multiplier_soil – Multiplier for soil samples used with detection limit to check the Absolute Difference for the FIELD DUPLICATE ABS DIFF rule as described below. Defaults to 2.

abs_diff_multiplier_water – Multiplier for water samples used with detection limit to check the Absolute Difference for the FIELD DUPLICATE ABS DIFF rule as described below. Defaults to 1.

one_detect_one_ND – Parameter to determine what to do when one of the results has a detected concentration and the other one is non-detect. Choices described in NON_DETECT rules below. Defaults to "CALC".

medium_code_soil – RT_MATRIX.MEDIUM_CODE for DT_SAMPLE.MATRIX_CODE for soil samples. Defaults to “Soil”.

medium_code_water – RT_MATRIX.MEDIUM_CODE for DT_SAMPLE.MATRIX_CODE for water samples. Defaults to “Water”.

rpd_control_limit_other – RPD control limit for other samples. Defaults to 25.

rpd_control_limit_soil – RPD control limit for soil samples. Defaults to 35.

rpd_control_limit_water – RPD control limit for water samples. Defaults to 20.

rpd_multiplier – Multiplier used with detection limit to determine when to calculate and check the Relative Percent Difference as described in the FIELD DUPLICATE RPD rule below. Defaults to 1.

sample_type_Field_Dup – Defaults to “FD”.

 

Notes:

The default value is used if there is no record in RT_DQM_CHECK_PARAM for an input parameter.

The default value is used if the PARAM_VALUE is NULL for this parameter in RT_DQM_CHECK_PARAM.

 

There are four rules and the first steps are:

 

Step 1: Find the samples with DT_SAMPLE.SAMPLE_TYPE = sample_type_Field_Dup. Then:

Step 2: Find the parent sample for each field duplicate using DT_SAMPLE.PARENT_SAMPLE_CODE or DT_FIELDQC_BATCH_PARTNER.QC_SAMPLE_ID.

Step 3: Process each CAS_RNs result for both samples. If both results are non-detect, skip to the next pair of results. If both have detected concentrations, then process these two rules:

 

1."FIELD DUPLICATE RPD"

a.If, for either result, DT_RESULT.RESULT_NUMERIC >=  rpd_multiplier * DT_RESULT.REPORTING_DETECTION_LIMIT, then calculate RPD and:

i.If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_soil, then qualify the results if  RPD> rpd_control_limit_soil

ii.If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_water, then qualify the results if  RPD> rpd_control_limit_water

iii.Otherwise, if MEDIUM_CODE is different or NULL, qualify the results if RPD > rpd_control_limit_other

 

2.  "FIELD DUPLICATE ABS DIFF"

       a.   If, for either result, DT_RESULT.RESULT_NUMERIC <=  abs_diff_multiplier * DT_RESULT.REPORTING_DETECTION_LIMIT, then calculate Abs Diff and:

            i.   If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_soil, then qualify the results if  Abs Diff > abs_diff_multiplier_soil
                *DT_RESULT.REPORTING_DETECTION_LIMIT

            ii.  If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_water, then qualify the results if  Abs Diff > abs_diff_multiplier_water
                *DT_RESULT.REPORTING_DETECTION_LIMIT

            iii. Otherwise, if MEDIUM_CODE is different or NULL, qualify the results if Abs Diff > abs_diff_multiplier_other *DT_RESULT.REPORTING_DETECTION_LIMIT

 

If one result has a detected concentration and the other is non-detect, then the one_detect_one_ND parameter provides three choices:

1."IGNORE" = Skip to the next pair of results.

2."QUALIFY" = Apply the Qualifier from the "FIELD DUPLICATE RPD NON_DETECT" rule to both results.

3."CALC" = Use the same two processes as above, but:

a.Use DT_RESULT.REPORTING_DETECTION_LIMIT in place of DT_RESULT.RESULT_NUMERIC for the non-detect result.

b.When the "FIELD DUPLICATE RPD" rule calls for the results to be qualified, use the qualifier from the "FIELD DUPLICATE RPD NON_DETECT" rule.

c.When the "FIELD DUPLICATE ABS DIFF" rule calls for the results to be qualified, use the qualifier from the "FIELD DUPLICATE ABS DIFF NON_DETECT" rule.

 

Note: The equation for RPD = 100 * ABS_VAL(DuplicateResult - ParentResult) / (0.5 * ABS_VAL(DuplicateResult + ParentResult)).