Overview
Laboratories can use different workflows to process sexual assault kit (SAK) evidence, and the workflow is often selected based on available resources. In an era of constrained local and state budgets, this cost-benefit analysis (CBA) tool provides a critical resource that practitioners and decision-makers can use to consider investing resources toward implementing a Direct-to-DNA SAK processing approach in lieu of serology screening.
With funding from the National Institute of Justice (NIJ) under the Forensic Technology Center of Excellence (FTCOE), RTI International developed this free to use SAK processing workflow CBA tool to help laboratory personnel and decision-makers understand the cost drivers of four SAK processing workflows, impacts on laboratory resources, and the potential benefits to overall public safety. This tool facilitates decision-making based on individual laboratory needs, functions, and resource availability. Additionally, this tool helps users better understand financial returns for implementing SAK workflows using a Direct-to-DNA or continuous sampling approach. Further, state and local policymakers can gain insights into the possible societal benefits from using a Direct-to-DNA SAK processing approach, which could lead to obtaining increased Combined DNA Index System (CODIS)-eligible profiles and resolving cases.
The aim of this tool is to assist laboratories in evaluating the impact of modified SAK processing workflows, including a Direct-to-DNA approach and continuous sampling strategy to obtain a CODIS-eligible profile, on overall labor related-costs and CODIS results.
Users are encouraged to report their findings, experiences, and insights using this prototype tool at ForensicCOE@rti.org. This feedback will be used for future enhancements to this tool to improve its benefit to the forensic science and criminal justice communities.
SAK Processing Workflows
The four SAK processing workflows examined within this CBA tool are as follows:
Serology Screening
- Serology is the first screening step.
- DNA quantitation is used to inform DNA amplification or used as a second screening step.
This workflow emphasizes working with “optimal” samples and does not include a procedure to exhaust all efforts (i.e., additional samples within a SAK request) to obtain a CODIS-eligible profile.
Serology Screening with Continuous Sampling*
- Serology is the first screening step.
- DNA quantitation is used to inform DNA amplification or used as a second screening step.
This workflow includes a procedure to continue testing samples within a SAK request to obtain a CODIS-eligible profile.
Direct-to-DNA
- No serology is used.
- DNA quantitation is used to inform DNA amplification and used as a screening step.
- Optimal samples are identified based on DNA ratio, and only optimal samples move forward to DNA amplification.
This workflow does not include a procedure to exhaust all efforts (i.e., additional samples within a SAK request) to obtain a CODIS-eligible profile.
Direct-to-DNA with Continuous Sampling*
- No serology is used.
- DNA quantitation is used to inform DNA amplification and used as a screening step.
- Optimal samples are identified based on DNA ratio, and only optimal samples move forward to DNA amplification.
This workflow includes a procedure to continue testing samples within a SAK request to obtain a CODIS-eligible profile.
*Continuous Sampling - A DNA testing procedure in which sample testing continues sequentially until a CODIS-eligible profile is obtained or until all SAK samples within a request are tested
User Guide
The FTCOE has developed a user guide for this CBA tool. It presents additional background information, the definitions used, the data needed in preparation for using the tool, how to properly interpret the outputs, and possible future directions. Users are encouraged to download and read through this user guide before opening the tool to ensure they have prepared all data for input. Additionally, the FTCOE encourages laboratories to refer to this user guide while inputting data or interpreting output results for additional guidance, as needed.
CBA Tool
This Excel-based CBA tool was designed to calculate the expected labor-related costs and CODIS outcomes for each of the four defined SAK processing workflow options. Pre-filled values in the User Input worksheet within this tool were developed using data provided from eight publicly funded U.S. crime laboratories. Users are encouraged to modify these default values, when applicable, to achieve results more representative of the workflow characteristics and costs of their laboratory. In the Results worksheet of this tool, users will find a detailed set of costs and CODIS outcomes by workflow. The Results worksheet also provides information on the expected incremental costs per 100 SAKs and per additional CODIS upload associated with changing SAK processing workflows. For example, adding continuous sampling will increase workflow costs but can also result in a slight increase of CODIS uploads. In these cases, this tool calculates the cost per additional CODIS upload to help laboratory personnel and decision-makers view the costs and benefits of adopting a new SAK processing workflow. For instance, laboratories may save money when switching to Direct-to-DNA by reducing labor hours in the workflow while increasing CODIS uploads. The magnitude of results will depend on the unique characteristics of each laboratory entered in the User Input worksheet.
Limitations and Considerations
- At this time, the CBA tool outputs are strictly related to labor expenditure associated with SAK processing workflow costs while the benefits are limited to the number of CODIS uploads and resulting CODIS hits. In the future, this tool could be expanded to include additional costs and benefits. For example, costs associated with a reduction in crime can be quantified in terms of economic and quality-of-life impacts for community members.
- Users should review all inputs before toggling to the Results worksheet to ensure they did not overlook any default value that may be updated to the current workflow data of their laboratory.
- This tool is not optimized for mobile devices. Some functions may not work or may appear truncated, and the level of data entry required may be too burdensome to input on a mobile device. A laptop or desktop computer is recommended when using this tool.
Funding for this project was provided by the Forensic Technology Center of Excellence and the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice.
The opinions, findings, and conclusions or recommendations expressed in this report are those of the author(s) and do not necessarily reflect those of the U.S. Department of Justice.
Contact us at ForensicCOE@rti.org with any questions and subscribe to our newsletter for notifications.
