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Collaborative Testing Services, Inc.   anniversary

P.O. Box 650820, Sterling, VA, USA 20165-0820  1-571-434-1925

Collaborative Testing Services is your Proficiency Testing Expert

CTS stands out among accredited proficiency test providers. Consider our many advantages:

Customers can communicate with CTS staff via telephone or e-mail on an unlimited number of topics from queries about current tests to the future of forensics testing. The availability and responsiveness of its staff sets CTS apart from every other provider.

CTS is the first, the largest and the most imitated forensics proficiency test provider. Our tests are the benchmark for the industry.
From Late Order Purchase tests (at no additional cost) to multiple choices in test format/delivery to the greatest diversity and frequency of Forensic Biology/DNA tests, CTS has the tests you want when you need them.
Our focus on interlaboratory tests is exclusive; meeting your proficiency testing needs is our only concern. To that end, our Individual Reports are clear and concise, allowing you to quickly review and interpret results.
Our Research Tests, which are offered on a one-time, limited enrollment basis, are designed to either push the edge of science in existing tests or venture into new testing areas/disciplines. Forensic Science is not static, and our growing catalogue of tests reflects that fact.
Active participation in associations and industry groups, attendance at conferences and service on industry and government panels means that CTS tests are relevant to the community and reflect the input of all stakeholders. We also appreciate the opportunity to work with our customers in fulfilling their quality assurance objectives. Your opinions, comments and input matter to us and are vital to ensuring that tests remain meaningful and case-like.
The most comprehensive online client portal of any provider and numerous tests available completely via digital download are just two of the ways that CTS improves the testing experience.

Since 1978, CTS has been your best choice in forensic proficiency testing.



About Collaborative Testing Services

It started with a question...
        ...How good are your measurements?

Collaborative Testing Services (CTS) was created in 1971 to meet the growing commercial demand for interlaboratory testing. The firm assembled a knowledgeable group of people with the expertise to guide the various aspects of interlaboratory programs. A cooperative effort among CTS, various trade associations, and the National Bureau of Standards (now called the National Institute of Standards and Technology) led to interlaboratory tests being offered by CTS in the areas of paper, containerboard and rubber. Over time, other industries came to recognize the value of this testing as well as the need to develop reliable test procedures. During the 1970s, CTS added color and forensic programs. The 1980s saw the establishment of a metals program, while the 1990s ushered in a testing program for plastics. Just prior to the start of the new millennium, CTS inaugurated interlaboratory tests for the wine industry.  CTS' history of service to diverse groups has carried forward into the new millennium; in 2007 CTS started the Agriculture Laboratory Proficiency (ALP) Program.
The geneses for the various programs are as diverse as the industries we serve. In some instances, organizations approached CTS to develop internal testing programs (e.g., to evaluate performance among multiple plant locations); a few of these grew into industry-wide programs. In other instances trade associations asked CTS to design programs for their industries. And in still others, CTS created tests to meet specialized needs, including ones to meet federal legislation, as well as proficiency tests for laboratory accreditation. A small number of programs have been discontinued as industry interest waned. Most programs, however, have stood the test of time and have decades of history to prove their worth to the laboratories, organizations and industries that participate.

A Joint Effort

Our name reflects the fact that we develop our interlaboratory testing programs in collaboration with relevant stakeholders  be they industry groups, technicians and bench personnel, government at all levels, quality assurance managers, equipment manufacturers and accreditation agencies. The results have been sustainable and meaningful testing schemes. By continuing to work with and listen to others, CTS is able to innovate (new tests, designs and delivery mechanisms), to implement service enhancing technology, and to meet customers ever-changing needs. We could not accomplish all of this without our full-time technical staff.

The Quest for Better Measurements Continues

Now more than ever, every measurement taken in your laboratory has the potential to have far-reaching effects on the quality efforts of your organization. CTS is committed to helping organizations achieve and maintain excellence in measurement quality through interlaboratory testing. Meeting this commitment requires that we establish high standards in all aspects of our business from selecting test materials to maintaining test integrity to providing responsive customer service. Our own activities must be governed by the highest possible quality standards. Therefore, CTS is accredited to ISO/IEC 17043:2010, "Conformity Assessment - General Requirements for Proficiency Testing."

History of the CTS Forensics Testing Program

Founding of CTS
CTS has been a forensic proficiency test provider since 1978, but the roots of the company's expertise in interlaboratory testing were established several years prior. CTS was started in 1971 by research associates of what was then the National Bureau of Standards (now the National Institute of Standards and Technology). The founding staff had been involved in interlaboratory testing for several years and brought with them to CTS an extensive knowledge of quality systems as well as a desire to help laboratories better demonstrate measurement competence. Initially, CTS designed and operated proficiency testing programs for Color and Appearance, Containerboard, Paper, and the Rubber industry.
Establishment of Forensics Proficiency Testing
From 1974-1977, the Law Enforcement Assistance Administration (LEAA) funded a project by the Forensic Sciences Foundation (FSF) whose objective was to determine the feasibility of proficiency testing as a tool to uncover problem areas in laboratory performance. Since CTS was already experienced in providing proficiency tests for other industries, the FSF retained CTS to assist in this project as well. The first Proficiency Advisory Committee (PAC) was appointed at that time by the FSF to provide advice and oversight. Overall, 219 laboratories in the US and Canada participated in the study; 21 tests were offered. The study concluded that a wide range of proficiency levels among the participating laboratories exists; however, it also concluded that properly supported, laboratories can be extremely proficient. Thus, once the LEAA-funded project was completed, the American Association of Crime Laboratory Directors (ASCLD) asked FSF and CTS to offer proficiency testing on an ongoing basis.
The CTS Forensics Program was formally started in 1978 as a commercial, subscription-based operation with initially 97 laboratories opting to participate. (The FSF-formed PAC became an ASCLD committee whose purpose was to technically advise FSF and CTS. In some cases, this technical oversight included actual manufacturing of the programs test samples by the PAC members.) As the value of such testing was proven time and again to the laboratories, and as laboratories could obtain funding for the tests, the program continued to steadily grow. In 1981, the ASCLD Laboratory Accreditation Board (ASCLD/LAB) introduced a formal forensic science laboratory accreditation program which required labs to have tests from approved external proficiency test providers as part of their quality assurance activities.
The FSF remained a program affiliate of CTS until 1992 when it was formally replaced by ASCLD, who continued the role of program affiliate and provided official certificates of participation to laboratories in the program. ASCLD continued in its role as program affiliate until 1998; the PAC continued to advise CTS until 2000. Eventually the PAC was succeeded by the ASCLD/LAB Proficiency Review Committees (PRCs). The PRCs were originally established by ASCLD/LAB in 1993 to review tests performed by accredited laboratories; it was a natural progression for these committees to replace the PAC and produce test-specific guidelines for the creation of proficiency tests under the ASCLD/LAB Proficiency Test Provider Program. ASCLD/LAB has since merged with ANAB (ANSI-ASQ National Accreditation Board).
Continued Growth and Evolution
Today approximately 900 laboratories in more than 80 countries participate in the CTS Forensics Program. In order to demonstrate its commitment to providing a high-quality testing program, CTS is accredited by ANAB to ISO/IEC 17043. In addition, CTS consults with a variety of technical industry groups, including ASCLD, IAI and IABPA, to name just a few. CTS works closely with relevant groups to receive technical guidance and to ensure the objectives, design and manufacture of each test meet current criteria for proficiency testing. Also, to meet the requirements of some international programs, specific questions are added to individual tests where necessary. All of these factors work together to ensure that the program continues to maintain the highest standards while effectively helping forensic laboratories meet their testing needs.
Over time, as both laboratory needs and capabilities have changed, so too have the CTS Forensic Proficiency tests. Some tests have proven to be stalwarts, kept in the program, albeit in changed forms as technology and science have changed. Others have fallen by the wayside as newer techniques have proven their worth. Working with the industry, CTS has conducted numerous research tests to allow for refining of testing techniques and the exploration of new methodologies. Several of these research efforts have led to the creation of proficiency tests within most disciplines and additional tests will continue to be developed as warranted.


Accreditation, Approvals and Recognitions

International Standards for Interlaboratory Testing

CTS is committed to helping organizations achieve and maintain excellence in measurement quality through interlaboratory testing. Meeting this commitment requires that we establish high standards in all aspects of our business: adhering to proven test design principles; selecting the best possible test materials; maintaining test integrity; providing responsive customer service; providing accurate, concise, and meaningful reports; and strictly protecting the confidentiality of our customers. Our own activities must be governed by the highest possible quality standards. CTS has been accredited by ANSI National Accreditation Board / ANAB to ISO/IEC 17043:2010, "Conformity Assessment - General Requirements for Proficiency Testing" since 2014. This is the international guideline for proficiency testing providers.


Role of Subcontractors

Various aspects of a proficiency testing scheme may, from time to time, be performed by an external provider. When this occurs, the activity is placed with an Approved Supplier and Collaborative Testing Services is responsible for this work. 

Acceptance for Proficiency Testing

The CTS interlaboratory testing programs are recognized by several organizations in North America including: the American Association for Laboratory Accreditation (A2LA); the American Society of Crime Laboratory Directors Laboratory Accreditation Board (ASCLD/LAB), which has merged with ANAB; the National Voluntary Laboratory Accreditation Program (NVLAP); ANSI National Accreditation Board/ANAB; National Aerospace Defense Contractors Accreditation Program; United Kingdom Accreditation Service; and the Standards Council of Canada. Memorandums of Understanding exist between these organizations and many others worldwide. Participants should always contact the appropriate organization to determine which CTS tests meet your specific accreditation/registration requirements.

CTS Forensic Proficiency Testing Program Overview

Sample Manufacture

Strict protocols are observed for the manufacturing of forensic tests. Before releasing a proficiency test, predistribution review is conducted by qualified experts to assess the test design and samples. This process, which is required of accredited proficiency test providers, helps ensure test validity. If you would like to conduct predistribution testing for any of our proficiency tests, please contact CTS for more information.

Sample Testing

After predistribution review, sample sets are sent (or released, in the case of digitally delivered tests) to participating laboratories. Data sheets are available on the CTS Customer Portal and provide a scenario (for most tests), a list of items submitted (sample items), any special instructions, and data sections in which to report the results. Depending on the test, these may include comparisons, identifications, interpretations and conclusions. Participants must submit their data to CTS by a specified Data Due Date. All proficiency tests also include an accreditation agency release form.

Manufacturer's Statement

Within three weeks after the test Data Due Date (six weeks for Drug Analysis tests) participants are notified that the Manufacturer's Information statement has been posted on the Customer Portal. This statement contains design specifications for the test samples and/or details of their preparation. The Manufacturer's Information is an interim report and does not necessarily represent the conclusions that should or can be obtained. Definitive interpretation of the results should be deferred until the release of the Summary Report.

Summary Report

The Summary Report containing the results for all participants is posted on the CTS website no later than 8 weeks after the test Data Due Date. To ensure confidentiality, each participant is identified in the report only by a "WebCode" number. This code is randomly assigned and changes with every report. Participants are advised to retain strict control over their WebCodes. Summary Reports issued during the previous five years can be found on this website. The Summary Reports for Research Tests are not available online; an electronic version is e-mailed to each participating laboratory.

Individual Report

When the Summary Report is posted on the CTS website, an Individual Report is e-mailed to each laboratory enrolled in that particular test, as well as uploaded to a laboratory's Portal account. This report is individualized  for each participant. If results were returned to CTS by the Data Due Date, the participant's data will appear on the Individual Report along with a brief summary of consensus information. If no results were returned the Individual Report will state No Results Reported for this Participant, but will still contain the brief summary information. Individual Reports are not issued for Research Tests. Instead each laboratory receives an electronic copy of the Summary Report.

Collaborative Testing Services' Subscription Information and Policies

These Subscription Policies apply to all tests on this CTS website, regardless of whether the tests were ordered from this website or by requesting a quote from CTS. Note that each CTS website has its own Subscription Information & Policies that pertain to the tests offered on that site.

Test Selection & Constraints
Select any combination of tests in which you wish to participate, noting any conditions specified for each test. CTS may limit participation in a test to a specified geographic region or impose special requirements. When selecting a test, the purchaser agrees to abide by any stated restrictions/requirements. If the purchaser is unable to comply, CTS will cancel the order for the test.
The prices listed beside each test are in U.S. dollars. The price charged is determined by the address to which CTS ships the test samples.
Enrollment Deadlines
Enrollment deadlines are strictly adhered to. Please pay special attention to the deadlines indicated for each test and contact CTS if you have questions.

Order Process
Participation is on a prepaid subscription basis. Subscriptions do not commence until funds are received and processed by CTS.

The order process starts with an order placed on a CTS website or a quote from CTS. A purchase order or payment must accompany the order or accepted quote. CTS will not continue the subscription order process without a payment or a purchase order.

Purchase Orders
CTS acknowledges that many organizations use purchase orders to obtain goods and services. If you choose to send a purchase order, please note that purchase orders are billed upon receipt; payment terms are Net Due. Test samples will not be shipped until invoices are paid in full. Customers receive a shipment hold notification via email if CTS has not received payment for test samples.

Payment Types Accepted
CTS accepts checks and all major credit cards. Checks must be in U.S. dollars drawn on a U.S. bank, made out to Collaborative Testing Services, Inc. Companies that prefer to send payments via ACH should submit ACH authorization forms to CTS' accounting department.

We also accept electronic funds transfers from our international customers. International organizations that wish to send electronic funds transfers should contact CTS for bank information. To ensure the payment is received in its entirety, it is the responsibility of the customer to pay any bank or wire fees.

If CTS receives a payment for an order and the payment is less than the total amount billed due to wire fees, tax withholding, or for any other reason, please note that the order will not be considered complete and samples will not ship on their predetermined schedule until CTS receives the full payment amount due.

Sample Replacement Policy
Requests for replacement of missing or damaged samples must be received no later than two weeks before the data due date. This is the minimum time frame in which we can guarantee you will receive the samples and still be able to complete the test by the deadline.

We suggest all package content be checked immediately upon receipt. All test samples are packaged independently of the outer wrapping. Therefore, opening the outer package to determine that all the contents are present and in good shape will not compromise the integrity of the test.
Data Submission Policy
CTS requires that results be returned by the date indicated on a data submission form. Late data will not be included for analysis. 

Cancellation Policy
This cancellation policy applies only to CTS Forensics tests (excluding Crime Scene Processing, see below).

Please review all test descriptions carefully. We encourage you to contact CTS with any questions before you place an order to ensure that your laboratory subscribes to the tests that best fit your requirements.

Our cancellation policy is as follows:

  1. All cancellation requests must be submitted in writing. A cancellation request is made when a customer no longer wishes to receive test samples or reports.
  2. Full credit will be issued only if a test is canceled before the published initial enrollment deadline (e.g., November 1, March 15, or June 15) that pertains to the test. Credit may only be applied to future CTS tests.
  3. No credit will be issued if a Late Order Purchase (LOP) test is canceled.
  4. No refunds of prepaid test fees will be issued for tests canceled by a subscriber.
  5. Accidental duplicate orders submitted by a subscriber are eligible for a full credit that may be applied to future CTS tests or a refund less the transaction fees incurred by CTS. To receive a credit or partial refund, the request must be received prior to the earliest applicable enrollment deadline associated with the order. Requests submitted after the earliest enrollment deadline are not eligible for a credit or partial refund.
  6. Samples are never re-used by CTS and therefore are not returnable. If a customer returns a sample package to our office, CTS will not provide a refund or credit of any portion of the subscription fee.
  7. Failure to remit a test fee, applicable shipping charges, or any required documents in a timely manner is considered by CTS to be a cancellation request.
  8. A test may be withdrawn if there are not enough subscribers to ensure the validity of the results. Test fees for withdrawn tests are refunded in full by CTS.
Crime Scene Processing Cancellation Policy 
As this testing is priced by the day, no refunds will be issued if a cancellation is required for individual scene(s).  If a cancellation of the full event is required, CTS will refund fees less the costs accrued.

International Orders
While all samples are labeled No Commercial Value some countries may assess duties or taxes or both. Customs, brokerage, and import fees are not included in the shipping charges or test fees. It is the responsibility of the recipient to pay those charges. Similarly, the recipient is responsible for providing any additional import documents that may be required by customs agencies.

CTS will make every effort to ensure proper delivery of your samples. All samples are sent via selected couriers to assure traceability; we automatically use a tracking service to locate lost shipments. If necessary, the decision to send replacement samples or issue a credit will be made on a case-by-case basis; however, CTS will not issue credits for samples that are delayed or refused entry into your country or are unclaimed by the recipient.

Due to the automated nature of CTS sample packaging and shipping process, international customers may not specify a courier or delivery method. Customers must accept the courier selected by CTS. With each sample package, CTS will include a standard commercial invoice (and an import or export permit if required for Drug Analysis samples). CTS cannot honor requests for custom, individual or additional shipping documents.

Feedback, Complaints and Appeals
All feedback, complaints and appeals shall be submitted in writing through one of the methods provided in the Contact Us page. CTS will acknowledge all submissions.

Participation in an interlaboratory testing program compares a laboratory's ability to conduct a particular test against other participating laboratories. The consensus results, however, are not a guarantee of performance.

CTS does not in any way grade the forensic test results. Whenever a laboratory chooses to submit its test results for accreditation, the laboratory's accrediting body solely determines whether or not that laboratory has met its proficiency testing requirement.

Collusion and falsification of results are prohibited. If collusion or falsification of results is identified, CTS may exclude participant results and will notify the participant(s) of CTS' decision.

If a sample distributed by CTS for use in a test should prove to be defective, CTS liability is limited to replacements of the samples, if time and supplies permit, or a refund of the test fee if the sample cannot be replaced.

Updated: 7 March 2024

Collaborative Testing Services' Confidentiality Policy

CTS is strongly committed to protecting the anonymity of participants in our interlaboratory testing programs and ensuring the confidentiality of both results and identifying information. The intent of this Confidentiality Policy is to describe our policies and practices regarding the disclosure of any and all information that may be used to identify participants and participant results. This policy includes, but is not limited to, this Web site.

Participating organizations designate a Laboratory Contact who is recognized by CTS as the sole person authorized to receive confidential information about that organizations participation, such as identifying information and performance results. Communication between CTS and participating organization is routinely routed through the Lab Contact. It is incumbent on the participating organization to designate a new Lab Contact if the existing contact is no longer authorized to act as the participants agent.

CTS assigns Lab Codes and/or Participant Codes to maintain the anonymity of participating organizations. These unique codes are used in combination with policies and procedures outlined below to communicate with a third-party while maintaining the anonymity of participants.

CTS randomly generates temporary WebCodes to protect the confidentiality of results. Webcodes also are used in combination with policies and procedures to ensure the confidentiality of interlaboratory results. WebCodes are assigned to participants and are used to identify results in Web-based summary reports. The Webcode is unique to each test and, therefore, is not permanently associated with a participant.

CTS will not confirm the participation of any individual or organization in our programs to a third-party without prior authorization of the participant. This authorization may be written authorization given directly to CTS by the participant for the release of information to a specific party. The authorization may also be given to the third party by the participant. This indirect, third-party authorization must include identifying information given to the third-party such as a Lab Code or Participant Code and identifying information that provides sufficient validation that the third party has been authorized by the participant.

CTS will not release, transmit, comment or discuss in any manner the results of a participant with a third-party without prior authorization of the participant. This authorization may be written authorization given directly to CTS by the participant for the release of information to a specific party. The authorization may also be given to the third party by the participant. This indirect, third-party authorization must include identifying information such as a Lab Code or Participant Code, the specific results to be released and identifying information that provides sufficient validation that the third party has been authorized by the participant.

CTS may share anonymous test results or aggregated test information and reserves the right to use any or all data in articles or other literature so long as there is no identifying information disclosed.

Confidentiality and Transmissions over the Internet
The transmission of data or information (including communications by e-mail) over the Internet or other publicly accessible networks is not secure, and is subject to possible loss, interception or alteration while in transit. Accordingly, we do not assume any liability for any damage you may experience or costs you may incur as a result of any transmissions over the Internet or other publicly accessible networks, such as the submission of any of your information to us (including your personal information). While we shall take commercially reasonable efforts to safeguard the privacy of any personal information you provide us and treat such information in accordance with this Confidentiality Policy, in no event will the information you provide to us result in any liability to you on our part in the event that such information is inadvertently released by us or accessed by third parties without our consent. Notwithstanding the foregoing, to the extent that you are able to access the information of third parties through our Web site, we do not grant you any right or license whatsoever to use such information.

Moreover, in order to limit unauthorized access, we observe strict security measures when it comes to archiving and divulging any information provided by our customers. Because of that, we may ask you to confirm your identity once again before submitting personal information.

Report Usage Policy

For all Reports: CTS strictly adheres to confidentiality policies regarding release of participant data, and published data is intended for internal use by participants. Further guidance for additional usage of reports is dictated by the relevant report type and their intended use, listed below.

Manipulation or misrepresentation of any CTS report is strictly prohibited.

Summary Reports: Summary Reports are a compilation of all results submitted by participants. Results in this report are presented as reported by the participants. The compiled results are not intended to be an overview of the quality of work performed in the profession and cannot be interpreted as such. Summary Comments are included for the benefit of the participants, and are not intended to reflect the general state of the art within the profession.  Summary Reports are made available to the general public on CTS' commercial web site.

Individual Reports: Individual Reports are results, analyses and additional information that provide a full assessment of the laboratory's measurement performance. The contents of these reports are primarily intended for internal use by the participants for quality assurance, technical competency, accreditation and recognition activities. CTS does not expressly prohibit participant release of Individual Report information to third parties.

Accrediting Body Reports: Accrediting Body Reports are results, analyses and additional information to permit Accreditation Bodies (ABs) to employ the testing to support accreditation programs. These reports are for the sole use by ABs and are submitted directly to the relevant AB. Inclusion of participant data in these reports shall be expressly granted to the Accrediting Body by the participant. Accrediting Bodies are not authorized to share or publish this data.


August 11 - August 17, 2024
Annual IAI International Forensic Educational Conference
Join us for the Annual IAI International Forensic Educational Conference in Reno, NV!


Facial Identification Proficiency Testing Now Available!
CTS is excited to announce a joint project with I³ for the creation and administration of Facial Identification Proficiency Testing! Enrollment in the test is open until 15 June 2024.

Don't see the test you desire?
Make a PT suggestion by emailing!

On-Demand Tests Available!
With unique sample sets for each test ordered, our on-demand forensic proficiency testing options for latent print, DNA, and drug disciplines (US customers only) allow your organization to complete testing on a flexible schedule. Individual Reports for these tests are available immediately following data submission.

Crime Scene Processing PT
Looking for a test that covers multiple Crime Scene skill sets? Enroll in our only monitored PT, where we come to you!

Get more information by e-mailing

Interested in becoming a Predistribution Test lab?
Click on the following link to learn more about CTS' predistribution testing and how you can participate and earn free tests.

Contact Us

Send inquiries / feedback / discussions regarding results to one of the following:
Mailing Address: 
Collaborative Testing Services, Inc.
P.O. Box 650820
Sterling, VA 20165-0820

Street Address for shipments & courier deliveries: 
21331 Gentry Drive
Sterling, VA 20166 

Tel 1-571-434-1925
Fax 1-571-434-1937 

Please send e-mail inquiries to the appropriate address: