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Forensic Science Communications October 2003 – Volume 5 – Number 4
Standards and Guidelines
Quality Assurance Guidelines for Laboratories Performing Microbial Forensic Work
Produced by the Members of the Scientific Working Group on Microbial Genetics and Forensics (SWGMGF)

Contact: Bruce Budowle, Chair, FBI Laboratory,
2501 Investigation Parkway, Quantico, Virginia 22135

June 20, 2003
Preface | Introduction | References | Scope | Definitions | Quality Assurance Program
Organization and Management | Personnel | Facilities | Sample Control | Validation
Analytical Procedures | Equipment Calibration and Maintenance | Reports | Review of Reports
Proficiency Testing | Corrective Action | Audits | Safety | Subcontractor of Analytical Testing

Preface

The Scientific Working Group on Microbial Genetics and Forensics (SWGMGF) has developed the following quality assurance guidelines to provide laboratories engaged in microbial forensic analysis with a framework to implement a quality assurance program. This document provides guidance to laboratories that carry out microbial forensic analysis to support the judicial system. Consideration may be given to alternate methods of achieving the intent of these quality assurance practices as outlined in these guidelines. A quality program is always evolving, and likewise, this document should be considered a living document. It is the intent of SWGMGF to modify this document as quality assurance practices in microbial forensics advance.

Introduction

The Quality Assurance Guidelines for Laboratories Performing Microbial Forensic Work provides a baseline from which laboratories may structure their quality assurance practices. Many of the recommendations outlined in this document will be familiar to laboratories already meeting ISO 17025 and CLIA '88 requirements. It is the intent of SWGMGF to provide the community with a source document for quality practices in the microbial forensics field.

References

American Society of Crime Laboratory Directors-Laboratory Accreditation Board (ASCLD/LAB), ASCLD/LAB Accreditation Manual, April 2001.

Federal Bureau of Investigation, Quality Assurance Standards for Forensic DNA Testing Laboratories (1998).

International Standards Organization (ISO)/International Electrotechnical Commission (IEC), ISO/IEC 17025, General Requirements for the Competence of Testing and Calibration Laboratories (1999) American National Standards Institute, New York, New York.

U.S. Department of Health and Human Services. Biosafety in Microbiological and Biomedical Laboratories, Fourth Edition, U.S. Government Printing Office, Washington, DC, April 1999.

CLIA '88. Code of Federal Regulations. Washington, DC, U.S. Government Printing Office, 2001, 57 CFR 7139 pp 883-999.

42 Code of Federal Regulations, Chapter IV (10-1-95 Edition), Health Care Financing Administration, Health and Human Services.

The CDC Interim Final Rule 42 CFR Part 73 Possession, Use, and Transfer of Select Agents and Toxins; Interim Final Rule; FR citation: 67 FR 76886.

The APHIS Interim Final Rule 7 CFR Part 331, repeated at 9 CFR Part 121 Agricultural Bioterrorism Protection Act of 2002; Possession, Use, and Transfer of Biological Agents and Toxins; Interim Final Rule; FR citation: 67 FR 76908.

1. Scope
  These guidelines describe quality assurance activities that a laboratory should follow to ensure the competency of the laboratory and the quality and integrity of scientific data. A laboratory, in the context of these guidelines, is defined as a facility in which microbial forensic testing is performed. These guidelines do not preclude a laboratory, by itself or in collaboration with others, from participating in research and development, or from using procedures that have not yet been validated by standard means for purposes other than forensic testing.
2. Definitions
 

As used in these guidelines, the following terms have the meanings specified:

Administrative review is an evaluation of examination documentation for consistency with laboratory policies and for editorial correctness.

Analytical procedure is an orderly step-by-step procedure designed to ensure operational uniformity and to minimize analytical drift.

Attribution is the information obtained regarding the identification or source of a material to the degree that it can be ascertained.

Audit is an inspection used to evaluate, confirm, or verify activities related to quality.

Biocrime or bioterrorism is the threat or use of microorganisms, toxins, pests, prions, or their associated ancillary products to commit acts of crime or terror.

BMBL is the Biosafety in Microbiological and Biomedical Laboratories (see References).

Calibration is a set of operations that establish, under specified conditions, the relationship between values provided by a measuring instrument, measuring system, and a known material or known values.

CDC is the Centers for Disease Control and Prevention.

Chain of custody is the tracking and documentation of physical control of evidence.

Contributing agency is identified as the organization that submitted the evidence to the laboratory for testing and which will receive the laboratory report.

Control samples or known samples are test materials whose identity, type, or values have been established. (e.g., blind samples, negative and positive controls).

Critical equipment or instruments are those requiring calibration prior to their initial use and on a regular basis thereafter.

Critical reagents are determined by empirical studies or routine practice to require testing on known samples prior to use with evidentiary materials in order to prevent unnecessary consumption of forensic samples.

Derivative evidence is material having originated from the original evidence (e.g., grown cultures, amplified DNA).

Examination documentation encompasses any documentation generated as a result of the analysis of submitted evidence. This may include technical notes, worksheets, charts, graphs, printouts, spectra, photographs, and other data or records used by examiners/analysts to support their reported conclusions.

Examiner/analyst (or equivalent role, position, or title as designated by the laboratory director) is an individual who conducts and/or directs the analysis of samples, interprets data, and reaches conclusions, and may eventually testify to those findings or conclusions.

Expert testimony is an opinion rendered by a qualified individual based on technical expertise or training.

Investigative support is data that provide the contributing agency with basic information to assist an ongoing investigation.

Laboratory is a facility in which microbial forensic testing is performed, a facility that contracts with another entity for such testing, or an entity contracted to perform analyses.

Laboratory support personnel (or equivalent role, position, or title as designated by the laboratory director) Is an individual(s) performing supportive laboratory duties but are not involved in the analysis or interpretation of evidence.

Microbial forensics is a scientific discipline that examines microorganisms, toxins, pests, prions, or their associated ancillary products for source attribution.

Proficiency test samples are materials whose identity, type, or values have been previously characterized and are used to assess the performance of a laboratory or an individual(s).

Proficiency testing is a quality assurance measure used to monitor performance and identify areas where improvements may be needed. Proficiency tests may be classified as:

  • Internal: A proficiency test that is prepared and administered within the laboratory being tested.


  • External: A proficiency test that is prepared by an external agency.

Qualifying test measures an individual's proficiency in both technical skills and knowledge and is administered prior to an individual assuming independent work responsibility.

Quality assurance is the system of management activities designed to ensure that a process, item, or service is of the type and quality needed. This includes monitoring activities that are intended to verify whether practices and test results are providing reliable and relevant information.

Quality control is a mechanism or laboratory activity intended to verify whether test conditions are functioning appropriately to yield reproducible results.

Quality manual is a document stating the quality policy, quality system, and quality practices of an organization.

Quality system is the organizational structure, responsibilities, procedures, processes, and resources for implementing quality management.

Reference material (certified or standard) is a material for which identities, types, or values are certified by technically valid procedures and is accompanied by, or traceable to, a certificate or other documentation.

Secure area is a locked space (e.g., cabinet, vault, room) with access restricted to authorized personnel.

Subcontractor is an individual or entity having a transactional relationship with a laboratory.

Technical manager (or equivalent position or title as designated by the laboratory director) is the individual who is accountable for the technical operations of the laboratory.

Technical review is an evaluation of reports, notes, data, and other documents to ensure that an appropriate and sufficient basis exists for the reported scientific conclusions.

Technician (or equivalent role, position, or title as designated by the laboratory director) is an individual who performs analytical techniques on samples under the supervision of an examiner/analyst.

Traceability is the property of a result of a measurement whereby it can be related to appropriate standards, generally international or national standards, through an unbroken chain of comparisons.

USDA is the United States Department of Agriculture.

Validation is a process by which a procedure is evaluated to determine its efficacy and reliability for analysis and includes the following:

  • Developmental validation is the acquisition of test data and the determination of conditions and limitations of a newly developed methodology for use on samples.


  • Preliminary validation is the acquisition of limited test data to enable an evaluation of a method used to assess materials derived from a biocrime or bioterrorism event.


  • Internal validation is an accumulation of test data within the laboratory to demonstrate that established methods and procedures perform within determined limits in the laboratory.
3. Quality Assurance Program
  3.1 The laboratory should establish and maintain a documented quality system that is appropriate to the testing activities.
    3.1.1 The quality manual should address, at a minimum, the following:
  • Goals and objectives


  • Organization and management


  • Personnel qualifications and training


  • Facilities and security


  • Sample control


  • Validation


  • Analytical procedures


  • Calibration and maintenance


  • Proficiency testing


  • Corrective action


  • Documentation and report writing


  • Review of reports


  • Safety


  • Audits


  • Monitoring subcontractor's work, if a subcontractor is used
  3.2 The laboratory should identify an individual as the quality manager.
4. Organization and Management
  4.1 A laboratory should:
  • have a managerial staff with the authority and resources needed to discharge their duties and meet the criteria of the guidelines in this document.


  • have a technical manager who is accountable for the technical operations.


  • specify and document the responsibility, authority, and interrelation of all personnel who manage, perform, or verify work affecting the validity of microbial forensic analysis.
  4.2 A laboratory should have a procedure for document control.
5. Personnel
  5.1 Laboratory personnel should have the education, training, and experience necessary to perform examinations and provide testimony. The laboratory should:
    5.1.1 have written job description(s) for personnel that include responsibilities, duties, and required skills.
    5.1.2 have a documented training program for assuring the competence of all technical laboratory personnel.
    5.1.3 have a documented program to ensure technical qualifications are maintained through continuing education.
      5.1.3.1 Continuing education - The technical manager and examiner/analyst(s) should stay abreast of developments within the field of microbial forensics by reading current scientific literature and by attending seminars, courses, professional meetings, or documented training sessions/classes in relevant subject areas at least once a year.
    5.1.4 maintain records on the relevant qualifications (including college transcripts), training, skills, and experience of all technical personnel.
    5.1.5 maintain records of security clearances, when appropriate, for laboratory personnel, when evidence/information must be secure and protected.
    5.1.6 obtain a nondisclosure agreement from employee, if required.
  5.2 The technical manager should have the following:
    5.2.1 Degree/experience requirements: The technical manager of a laboratory should have, at
a minimum, one of the following combinations of education/experience:
  • Master's degree in biology, microbiology, clinical laboratory science, or other relevant science. Within the last eight years: a minimum of four years' work experience in a laboratory with at least one year in the relevant field and one year's supervisory experience.


  • Doctorate degree in medicine, biology, microbiology, clinical laboratory science, or other relevant science. Within the last four years: a minimum of two years' work experience in a laboratory with at least one year in the relevant field and one year of supervisory experience.
 
    5.2.2 Duty requirements:
      5.2.2.1 General: manages the technical operations of the laboratory.
      5.2.2.2 Specific duties:
  • Is responsible for evaluating and approving all methods used by the laboratory and for proposing new or modified analytical procedures to be used by examiners.


  • Is responsible for technical problem solving of analytical methods and for the oversight of training, quality assurance, safety, and proficiency testing in the laboratory.


  • Has the authority to suspend laboratory operations.
      5.2.2.3 The technical manager should be accessible to the laboratory to provide on-site, telephonic, or electronic consultation, as needed. The technical manager should spend at least 50 percent of the work year at the laboratory facility.
  5.3 Examiner/analyst should have the following:
    5.3.1 Degree requirements: An examiner/analyst should have, at a minimum, a bachelor's degree or its equivalent in biology, microbiology, clinical laboratory science, or other relevant science.
    5.3.2 Experience requirements: An examiner/analyst should have a minimum of 12 months' laboratory experience.
    5.3.3 Duty requirements: An examiner/analyst is responsible for the content of a laboratory report released under his/her name and provides expert courtroom testimony, if required.
    5.3.4 Training requirements: An examiner/analyst should have successfully completed a documented training program and qualifying test before assuming independent work responsibilities. The training program should require a minimum of four months and include the successful analysis of a range of samples typically encountered in his/her area of microbial forensics and provide an understanding of forensic operations.
  5.4 Technician should have:
    5.4.1 On-the-job training specific to the job function(s) performed.
    5.4.2 Successfully completed a qualifying test before participating in forensic testing responsibilities. Documentation of testing should be retained.
  5.5 Laboratory support personnel should have training, education, and experience commensurate
with their responsibilities as outlined in their job description.
6. Facilities
  6.1 The laboratory should have a facility that is designed to provide appropriate levels of security, safety, and minimize contamination. Laboratory management should ensure that:
    6.1.1 Access to the laboratory is controlled and limited.
    6.1.2 Evidence is appropriately secured and stored when not under examination.
    6.1.3 Preamplification materials and activities are separated by time or space from postamplification products and activities.
    6.1.4 The laboratory follows written procedures for monitoring, cleaning, and decontaminating facilities and equipment.
    6.1.5 When CDC (BMBL) and/or USDA guidelines for biolevel containment are employed, appropriate protocols and records should be maintained.
  6.2 A laboratory should document waste management requirements to ensure that appropriate decontamination and disposal measures are in accordance with federal and/or state law.
  6.3 A laboratory should consider measures to address the following:
  • Backup power sources for power outages to protect evidence from temperature fluctuations, when appropriate. Twenty-four-hour emergency notification procedures are advisable.

  • Computer security and backups for data and case documentation records.
7. Sample Control
  7.1 The laboratory should have and follow a documented sample inventory control system. This system should ensure that:
    7.1.1 Samples are marked with unique identifiers.
    7.1.2 Documentation of sample identity, receipt, storage, and disposition is maintained.
    7.1.3 The laboratory follows documented procedures that minimize sample loss, contamination, and/or deleterious change.
    7.1.4 The laboratory has secure areas for sample storage including environmental control consistent with the form or nature of the sample.
  7.2 The laboratory should have available guidelines for sample collection and should request the following information from the submitter of samples:
    7.2.1 Sample collected from an individual: If available, type of sample (method of collection and anatomical site from which collected), age, gender, population affinity, weight, body temperature, current medications, who collected sample, time and date of collection, and postcollection and transportation conditions. When multiple samples are collected from the same individual, appropriate delineation should be provided to distinguish samples. Additionally, for nonhuman samples, species, animal, or plant identification number should be recorded.
    7.2.2 Sample collected from a location: If available, type of sample, sampling tool, date and time collected, and who collected the sample. When multiple samples are collected from the same site, appropriate delineation should be provided to distinguish samples. Sample location and condition of location at time of sample collection should be recorded. Conditions of storage and transport should be documented.
  7.3 The laboratory should maintain a chain of custody for forensic samples from the time of receipt in the laboratory. Individual items should be tracked. Time and date of sample transfers should be documented. Derivative evidence should be tracked.
  7.4 When the laboratory consumes tested samples, that fact should be documented in the case notes.
  7.5 If tested samples, or derivative evidence thereof, are released to a database, this should be recorded in the case notes and the chain-of-custody documentation.
  7.6 A laboratory should document and provide appropriate guidelines for sample submission, packaging, and return.
  7.7 A laboratory should document a policy of long-term sample storage, retention, disposal, and/or return.
8. Validation
  8.1 The laboratory should use validated methods and procedures for analyses.
    8.1.1 Developmental validation should be appropriately documented and should address specificity, sensitivity, reproducibility, bias, precision, false-positives, false-negatives, and determine appropriate controls. Any reference database used should be documented.
    8.1.2 Preliminary validation is the acquisition of limited test data to enable an evaluation of a method used to provide investigative support to investigate a biocrime or bioterrorism event. If the results are to be used for other than investigative support, then a panel of peer experts, external to the laboratory, should be convened to assess the utility of the method and to define the limits of interpretation and conclusions drawn.
    8.1.3 Internal validation should be performed and documented by the laboratory.
      8.1.3.1 The procedure should be tested using known samples. The laboratory should monitor and document the reproducibility and precision and define reportable ranges of the procedure using control(s).
      8.1.3.2 Before the introduction of a new procedure into sample analysis, the analyst or examination team should successfully complete a qualifying test for that procedure.
      8.1.3.3 Material modifications made to analytical procedures should be documented and subjected to validation testing commensurate with the modification and have documented approval.
9. Analytical Procedures
  9.1 The laboratory should have and follow written analytical procedures reviewed and approved by the laboratory management/technical manager.
    9.1.1 The laboratory should have a documented procedure for each analytical technique used.
    9.1.2 The laboratory should have a documented approach for testing general unknowns.
    9.1.3 The procedures should include a list of equipment and reagents, step-by-step instructions, quality controls, test calculations, limitations, interpretation criteria, and literature references.
    9.1.4 The laboratory should have a policy whereby a deviation from an analytical procedure is documented and approved.
  9.2 The laboratory should use reagents that are suitable for the methods employed.
    9.2.1 The laboratory should have written procedures for documenting dates of receipt and expiration of commercial supplies and for the formulation of reagents. Lot numbers should be recorded.
    9.2.2 Reagents should be labeled with the identity of the reagent, the date of preparation and expiration, the identity of the individual preparing the reagent, and storage instructions.
    9.2.3 The laboratory should identify critical reagents, if any, and evaluate them prior to use (e.g., restriction enzymes, primers, antibodies, growth media prepared in the laboratory).
10. Equipment Calibration and Maintenance
  10.1 The laboratory should use equipment suitable for the methods employed.
  10.2 The laboratory should identify critical equipment and should have a documented program for calibration and, when appropriate, monitoring of instruments and equipment.
    10.2.1 When available and appropriate, standards traceable to national or international standards should be used for calibration. When traceability to national standards of measurement is not applicable, the laboratory should provide satisfactory evidence of correlation of results.  
    10.2.2 The frequency of the calibration should be documented for each instrument requiring calibration. Such documentation should be retained in accordance with appropriate federal and state law.
  10.3 The laboratory should have and follow a documented program to ensure that instruments and equipment are properly maintained.
    10.3.1 New critical instruments and equipment, or critical instruments and equipment that have undergone repair or maintenance, should be calibrated before use.
    10.3.2 Written records or logs should be kept for maintenance service performed on instruments and equipment. Such documentation should be retained in accordance with federal and state law.
11. Reports
  11.1 The laboratory should have and follow written procedures for generating and maintaining documentation for tested samples.
    11.1.1 The laboratory should have written procedures for the release of tested sample information.
    11.1.2 A laboratory report should include the following:
  • Name of submitting agency


  • Date the sample(s) was received in the laboratory


  • Brief description of all evidence submitted, including the indicated source of the sample, when available (e.g., lungs, circulatory, water source, debris)


  • Statement to address the specific request made of the laboratory


  • General statement of analytical method used


  • Analytical results and interpretive statement to provide clarity of result


  • Statement of negative results, when appropriate


  • Statement of recommended additional testing, when appropriate (e.g., additional testing after 6 and 12 days is suggested so as to determine exact exposure date)


  • Laboratory location (city, state)


  • Identity of the person responsible for the technical conclusions of the laboratory report


  • Identification of all components of the analysis completed using subcontractors
  11.2 The laboratory should maintain, at a minimum, the following examination documentation:
  • Analyst- and technician-generated notes, to include identity of person generating notes


  • List of instrumentation used (by specific identifier, if appropriate)


  • All charts, graphs, photographs, and other examination-related records


  • Chain of custody


  • Description of evidence


  • Dates of analysis


  • Any deviations from examination protocol


  • Statement regarding any consumption/disposition of evidence


  • The identity of individuals performing technical and administrative reviews of the report
12. Review of Reports
  12.1 The laboratory should have and follow written procedures for technically reviewing all tested sample information and results. The technical review is conducted by a technically qualified individual other than the preparer of the report, notes, data, and other documents under review. All reports should be administratively reviewed.
    12.1.1 The laboratory should have a documented mechanism in place to address discrepant interpretations and/or conclusions between analyst(s) and reviewer(s) and a mechanism to address unresolved conclusions/interpretations.
  12.2 The laboratory should have a practice in place to review and address reports of noncompliance (e.g., findings resulting from audit reports, contamination logs, controls not functioning properly).
13. Proficiency Testing
  13.1 Examiners and other personnel designated by the technical manager who are actively engaged in analysis should undergo annual proficiency testing. The test samples should be processed and analyzed in the same manner as casework. Successful completion of annual testing is required to continue casework.
    13.1.1 In accordance with appropriate federal and state law, the laboratory should maintain the following proficiency test documentation:
  • Test set identifier


  • Identity of the test participant


  • Distribution date and due date


  • Date of analysis and completion


  • All data and notes supporting the conclusions


  • Proficiency test results


  • Any discrepancies noted


  • Corrective actions taken


  • Retention, if possible, of a portion of each proficiency test for reanalysis and comparison, if circumstances dictate
    13.1.2 Records for each individual tested should be maintained, including all notes, records, reports, and evaluations.
  13.2 The following proficiency test information should be documented for tests prepared within the laboratory:
  • Identity of person(s) who prepared the test samples


  • Date test samples were prepared


  • Test identifier


  • Sufficient information to duplicate test preparation


  • Expected results, including acceptable limits (if appropriate)
14. Corrective Action
  14.1 The laboratory should establish and follow procedures for corrective action whenever analytical errors and/or proficiency testing discrepancies are detected. The laboratory should maintain documentation for the corrective action. Such documentation should be retained in accordance with appropriate federal or state law.
15. Audits
  15.1 The laboratory should conduct audits annually in accordance with the guidelines outlined herein.
    15.1.1 Audit procedures should address, at a minimum, the following:
  • Quality assurance program


  • Organization and management


  • Personnel


  • Facilities and security


  • Sample control


  • Validation


  • Analytical procedures


  • Calibration and maintenance


  • Proficiency testing


  • Corrective action


  • Documentation and report writing


  • Review of reports


  • Safety


  • Previous audits
    15.1.2 The laboratory should retain all documentation pertaining to audits in accordance with applicable federal and state laws.
  15.2 A second agency should conduct an external audit once every two years.
16. Safety
  16.1 The laboratory should have and follow a documented environmental health and safety program. This program should include a documented ongoing safety training program for laboratory personnel and should be in accordance with applicable federal and state laws.
  16.2 The laboratory should identify an individual as the safety officer.
  16.3 Laboratories employing biosafety level 2 or higher should meet applicable current CDC (BMBL) and/or USDA guidelines.
17. Subcontractor of Analytical Testing
  17.1 The submitting agency should be notified and approve if its samples will be tested by a subcontracted laboratory. The laboratory will be notified and approve the use of a subcontractor by the subcontractor laboratory for testing of samples.
  17.2 A laboratory operating under the scope of these guidelines should require certification of compliance with those portions of these guidelines appropriate to the analysis when a subcontractor performs analyses for the laboratory. A contracting laboratory may choose to require documentation of a laboratory following these guidelines before submitting samples for analysis.
    17.2.1 The laboratory should establish and use appropriate review procedures based on the type of work being provided by the subcontracting laboratory. This is to verify the integrity of the data received from the subcontractor. The review includes, but is not limited to:
  • Visual or expert system inspection and evaluation of all results and/or data


  • Inclusion of quality control samples


  • Annual on-site visits
  17.3 Laboratories that use specialty contractors to fulfill narrowly focused analytical methods (e.g., genomic sequencing) should require the contractor to provide a minimum of the following documentation:
  • Copy of the step-by-step analytical procedure used by the laboratory


  • Identity of the person responsible for analysis results


  • Analytical controls used during analysis


  • Identity of all persons involved in the testing of the samples


  • Chain of custody
  17.4 The contracting laboratory should define a policy for notification of applicable personnel changes by the subcontracting laboratory.