Standard for the Development and Internal Validation of 

Forensic Serological Methods

Standard for the 

Development and Internal 

Validation of Forensic 

Serological Methods

Biological Methods Subcommittee

Biology/DNA Scientific Area Committee

Organization of Scientific Area Committees (OSAC) for Forensic Science
Standard for the Development and Internal Validation of 

Forensic Serological Methods

OSAC Proposed Standard

Standard for the Development and 

Internal Validation of Forensic 

Serological Methods

Prepared by 

Biological Methods Subcommittee

Version: 1.0

2018

Disclaimer:

This document has been developed by the Biological Methods Subcommittee of the Organization 

of Scientific Area Committees (OSAC) for Forensic Science through a consensus process and is 

proposed for further development through a Standard Developing Organization (SDO). This 

document is being made available so that the forensic science community and interested parties 

can consider the recommendations of the OSAC pertaining to applicable forensic science 

practices. The document was developed with input from experts in a broad array of forensic 

science disciplines as well as scientific research, measurement science, statistics, law, and policy. 

This document has not been published by an SDO. Its contents are subject to change during the 

standards development process. All interested groups or individuals are strongly encouraged to 

submit comments on this proposed document during the open comment period administered by 

the Academy Standards Board (www.asbstandardsboard.org). 
Standard for the Development and Internal Validation of 

Forensic Serological Methods

Foreword

This standard was revised, prepared and finalized as a standard by the DNA Consensus Body of the

AAFS Standards Board (ASB). The initial draft document was developed by the Biological Methods

Subcommittee of the Organization of Scientific Area Committees for Forensic Science.

This standard provides requirements on how a laboratory validates new forensic serologicalfor the 

validation of methods that will be used to evaluate body fluids, stains, or residues related to 

forensic investigations. A validation should include studiescharacterization of the performance 

characteristics of a techniquetest procedure, limitations of the techniquemethod, and the 

identification and documentation of influences that may change performance characteristics. 

In this document the industry standard definition for serology as it relates to forensic science is 

used instead of the traditional scientific definition.

All hyperlinks and web addresses shown in this document are current as the publication date of

this standard.

Keywords: forensic serology, validation, internal validation, developmental validation, forensic

biology
Standard for the Development and Internal Validation of 

Forensic Serological Methods

Table of Contents

1 Scope........................................................................................................................................................................................

2 Normative References ......................................................................................................................................................

3 Terms and Definitions ......................................................................................................................................................

4 Requirements.......................................................................................................................................................................

4.1 Developmental Validation...........................................................................................................................................

4.2 Internal Validation .........................................................................................................................................................

5 Validation Documentation..............................................................................................................................................
Standard for the Development and Internal Validation of 

Forensic Serological Methods

1

Standard for the Developmental and Internal Validation of Forensic 

Serological Methods

1 Scope

This standard provides requirements for developmental and internal validations of forensic 

serological methods to evaluate body fluids, stains, or residues related to forensic investigations. 

This standard does not address validation of forensic DNA analysis procedures.

2 Normative References

The document contains no normative references. See Annex A, Bibliography for other references.

3 Terms and Definitions

3.1

characterization of the test procedure 

IncludesComprises the components of the test, the procedure used, limitations of the test, and the 

methods for detection and analysis.

3.1

including whether the test is presumptive or confirmatory testsand the type of body fluid, stain, 

or residue being targeted. 

3.2

confirmatory test

A test that is specific for the presence of a particular biological material. Confirmatory tests are 

specific for the biological materialbody fluid, stain, or residue of interest, and reducereduces or 

eliminateeliminates false positive results.

3.3

contamination

The unintentional introduction of exogenous materials or substancesubstances into a test sample.

3.4

contamination studies 

VerifyExperiments performed to assess the risk that theunintended material may be introduced 

into a sample from test assay components, instrumentation, the operator, and test procedure are 

not introducing material into the sampleor test procedures.

3.5

controls 

Samples of known type, run in parallel with experimental, reference, or evidence samples that are 

used to demonstrate that a procedure is working correctly.

3.6

control studies
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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StudiesExperiments performed to establish the necessary controls for each procedure, the 

frequency with which the controls should be performed (e.g., concurrently, daily, before use, etc.) 

and the performance expectations for each control.

3.7

developmental validation

The acquisition of test data and determination of conditions and limitations of a new 

methodology; Thisthis generally occurs while the conditions and parameters are being worked 

out prior to the establishment of a defined assay, procedure or product. Internal validation 

studies typically follow developmental validation studies.

3.8

forensic serology

In general, theThe detection, characterization, identification, and/or typing of body tissues and 

fluids, either in native form or as stains or residues left at a crime scene using physical methods 

(e.g. normal and enhanced lighting), biochemical assays, reactions and/or microscopy; this 

definition applies to current crime biology laboratory practices which may be followed by DNA 

testing. .

3.9

internal validation

The accumulation of test data within the laboratory for developing the laboratory standard 

operating procedures and determining the limits of the method(s). Internal validation

demonstrates that the established protocols for the technical steps of the test and for data 

interpretation perform as expected in the laboratory.

3.10

interference studies

DetermineExperiments performed to determine substances that inhibit or effectaffect the 

intensity of the assay signal.

3.11

material modification

An alteration of an existing analytical procedure that may affect analytical results.

3.11

mixture studies

Studies ofExperiments performed to evaluate the effect ofperformance of the test method when 

samples containing mixtures of similar or different body fluids/ and/or cell types on the 

capability of the testare assayed. 

3.12

mock casework samples

Samples of known origin that mimic or simulate a range of casework sample types that may 

include laboratory created samples or proficiency test samples.

3.13

performance check

A quality assurance measure to assess the functionality of laboratory instruments, reagents and 

equipment that affect the accuracy and/or validity of forensic sample analysis.
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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3.14

population studies 

DetermineExperiments performed to determine the variation in responseeffectiveness of the test 

when utilized with representative samples originating from the general population.

3.15

presumptive teststest

A screening test which may be positive in the presence of a biological material of interest. 

PresumptiveSome presumptive tests are sensitive, but not specific. A positive result indicates that 

further testing could be informative.

3.16

repeatability studies

VerifyExperiments performed to verify the results of the assay by the same personnel and/or 

applicable instrumentation.

3.17

reproducibility studies

Test the assay’s abilityExperiments performed to assess the capability to obtain the same test 

results when an experiment is repeated between different operators and/or detection 

instruments. 

3.18

robustness studies

TestExperiments performed to measure the abilitycapability of thea procedure to produce an 

outcome that will be relativelyremain unaffected by the presence of a small number of unusual or 

incorrect data valuesbut deliberate variations in method parameters and provide an indication of 

reliability during normal usage.

3.19

sensitivity studies

A set of critical studies toExperiments performed to define the lower and upper limits/bounds of 

an assay to accurately detect an analyte. Experiments include a serial dilution performed during 

developmental and/or internal validation of methods designed to define the lower and upper 

limits/bounds of an assay to accurately detect an analyte.

3.20

specificity studies

TestsExperiments performed to evaluate the ability of the system to provide reliable results for 

targeted analytes in the presence of cross-reactive substances.

3.21

stability studies

TestExperiments performed to test the assay with various substrates that were subjected to 

different environmental and chemical insults including storage, handling conditions, and time 

interval studies.

3.22

technical designee

The designated individual in the laboratory who has technical responsibility.
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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4 Validation Requirements

4.1 General 

4.1.1 The laboratory shall use validated methods for all presumptive and confirmatory tests. 

Developmental and internal validation shall precede the implementation of any new methods 

used for forensic serological analysis.

4.1.2 The laboratory shall use different samples for developmental validation studies and 

internal validation studies.

4.1.24.1.3 The technical designee shall determine if the number, types and range of sample 

types to be used in each of the validation samples isstudies to ensure the generation of sufficient 

data to establish a standard operating procedure.

4.1.4 Material modifications madeThe internal validation shall not exceed the scope of the 

conditions tested in the developmental validation. Samples that fall outside the range of 

conditions used in developmental validation shall require additional developmental validation 

studies.

4.1.34.1.5 Any change to a validated proceduresprocedure shall be documentedevaluated to 

determine if analytical results are affected. If a modification has the potential to affectaffects the 

analytical result, the performance of a modified procedure or additional instrumentation shall be 

evaluated prior to use on evidence. If the analytical results are affected, the procedure shall 

require an additional validation prior to implementation. The validation or evaluation of the 

material If the analytical results are not affected, the modification shall conform to the 

requirements in this standard and shall include a comparison of the modified method to the 

original method which was modified. Material modification and evaluation documentation shall 

be included with the validation.. The evaluation of changes to validated procedures shall conform 

to requirements of this standard and all comparisons, evaluations, modifications, and validations 

shall be documented. 

4.1.44.1.6 For laboratory systems that consist of more than one laboratory, validation 

studies may be shared; however, performance checks shall be conducted and documented at each 

site.

4.2 Developmental Validation

A developmental validation study shall include the following:

⎯ characterization of the test procedure,

⎯ control studies;

⎯ interference studies,

⎯ population studies,

⎯ reproducibility studies,
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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⎯ robustness studies,

⎯ sensitivity studies,

⎯ specificity studies,

⎯ stability studies,

⎯ mixture studies,

⎯ the analysis of mock or adjudicated casework samples.

4.3 Internal Validation

An internal validation study shall include the following:

⎯ contamination studies;

⎯ control studies;

⎯ repeatability studies;

⎯ reproducibility studies;

⎯ sensitivity studies;

⎯ specificity studies;

⎯ mixture studies;

⎯ the analysis of mock or adjudicated casework samples.

4.4 Validation Documentation

4.4.1 The laboratory shall identify and maintain a list of the scientific literature describing the 

test, its limitations, and/or the scientific principles that serve as itsa foundation.
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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4.4.2 The laboratory shall have at a minimum a summary of data from the developmental 

validation to support any internal.

4.4.24.4.3 Developmental validation studydocumentation shall include any limitations of the 

method.

4.4.34.4.4 If a required component is not performed as part of a developmental or internal 

validation, documentation must be included to warrant the omission. 

4.4.44.4.5 The technical designee shall document the review and approval of all validations, 

modifications to procedures or equipment, and performance checks. Other approvals may be 

necessary according to laboratory policy.

4.4.54.4.6 The technical designee shall review and approve any new or revised standard 

operating procedures as a result of internal validation or procedure modifications. Other 

approvals may be necessary according to laboratory policy.

4.4.64.4.7 The laboratory shall have a policy for retention of the summary and data 

correlating to developmental validations, internal validations, modificationsmodification to the 

procedures, and performance checks.

5 Conformance

In order to demonstrate conformance with this standard, the laboratory shall have the following:

a) documentation of the developmental validation which can be internal, external, or 

documented in the peer reviewed literature;

b) documentation of all internal validation; studies, data, and outcomes;

c) documentation of any modification to the procedures, if applicable; and

c) documentation of performance checks.

d) Studies to establish the necessary controls for each procedure, the frequency with which the 

controls should be performed (e.g., concurrently, daily, before use, etc.) and the performance 

expectations for each control, if applicable.
Standard for the Development and Internal Validation of 

Forensic Serological Methods

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Annex A

(informative)

Bibliography

1) Scientific Working Group on DNA Analysis Methods (SWIGDAMSWGDAM): Guidelines for the 

Collection and Serological Examination of Biological Evidence, issue date 01/15/2015: 

http://media.wix.com/ugd/4344b0_bce915901bb14b9cb36049df6a8441e2.pdf