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| [[File:Nuclear Forensics (02813659) (14418094348).jpg|right|300px]] | | <div class="nonumtoc">__TOC__</div> |
| '''Title''': ''What are the key elements of a LIMS for forensics and medical examiners?''
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| | | text = This is sublevel5 of my sandbox, where I play with features and test MediaWiki code. If you wish to leave a comment for me, please see [[User_talk:Shawndouglas|my discussion page]] instead.<p></p> |
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| '''Author for citation''': Shawn E. Douglas
| | ==Sandbox begins below== |
| | | {{raw:wikipedia::Detection limit}} |
| '''License for content''': [https://creativecommons.org/licenses/by-sa/4.0/ Creative Commons Attribution-ShareAlike 4.0 International]
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| '''Publication date''': June 2022
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| ===Summary===
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| A [[Forensic science|forensics and medical examiners lab]] may analyze anything from body fluids and bone fragments to metals and fire debris as part of their broad commitment to answering questions of interest to a legal system. These [[laboratory]]-based investigations see scientists collect, preserve, and analyze these types of [[Sample (material)|samples]] (i.e., evidence) using a variety of special laboratory equipment and techniques. Given their role in verifying the status of evidence, the forensics lab will also see its laboratorians take part in legal proceedings, requiring even more strict requirements for data and evidence management. This broad array of analytical techniques and set of legal implications means such labs turning to [[Informatics (academic field)|informatics]] solutions like the [[laboratory information management system]] (LIMS) will require their [[information management]] solutions to meet the specific needs of their lab.
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| This brief topical article will examine the typical forensics and medical examiners lab's [[workflow]] and suggest a base set of LIMS functionality (i.e., system requirements) that is critical to fulfilling the information management and workflow requirements of this lab type.
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| '''Note''': Any citation leading to a software vendor's site is not to be considered a recommendation for that vendor. The citation should however still stand as a representational example of what vendors are implementing in their systems.
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| ===Forensics laboratory workflow, workload, and information management===
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| The U.S. Department of Justice (DOJ) duly notes the practice of forensic science is multi-disciplinary, spanning from forensic chemistry, molecular biology, and toxicology to anthropology and entomology.<ref name=":0">{{Cite web |last=Office of Legal Policy |date=26 November 2021 |title=Forensic Science |url=https://www.justice.gov/olp/forensic-science |publisher=U.S. Department of Justice |accessdate=13 June 2022}}</ref> This suggests that depending on what a forensics lab or researcher is focusing their efforts on, workflows may differ, sometimes significantly. These workflows may be further complicated by activities outside the laboratory, including collecting evidence, giving testimony, providing forensic psychiatry services, or conducting forensic engineering investigations.<ref name=":0" /> This typically results in diverse types of information and data being collected both physically and digitally inside and outside the forensics lab, at all hours of the day. Additionally, the integrity of that information, data, and evidence is vital to establishing legal provenance and positively developing forensic intelligence.<ref>{{Cite journal |last=McCartney |first=Carole |date=2015-01-02 |title=Forensic data exchange: ensuring integrity |url=http://www.tandfonline.com/doi/abs/10.1080/00450618.2014.906654 |journal=Australian Journal of Forensic Sciences |language=en |volume=47 |issue=1 |pages=36–48 |doi=10.1080/00450618.2014.906654 |issn=0045-0618}}</ref> This is where a well-developed and -maintained LIMS comes into play.
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| The use of LIMS in crime labs has grown over time, with the DOJ's Bureau of Justice Statistics (BJS) reporting 75% of publicly funded crime labs using a LIMS in 2002 and 84% in 2009.<ref name="DuroseCensus12">{{cite web |url=https://bjs.ojp.gov/content/pub/pdf/cpffcl09.pdf |format=PDF |title=Census of Publicly Funded Forensic Crime Laboratories, 2009 |author=Durose, M.R.; Walsh, K.A.; Burch, A.M. |publisher=Bureau of Justice Statistics |date=August 2012 |accessdate=14 June 2022}}</ref> (A separate survey by Levy in 2011 found 82% of surveyed death investigation offices were using LIMS.<ref name="LevyImplem13">{{Cite journal |last=Levy |first=Bruce P. |date=2013-03 |title=Implementation and User Satisfaction With Forensic Laboratory Information Systems in Death Investigation Offices |url=https://journals.lww.com/00000433-201303000-00016 |journal=American Journal of Forensic Medicine & Pathology |language=en |volume=34 |issue=1 |pages=63–67 |doi=10.1097/PAF.0b013e31827ab5c6 |issn=0195-7910}}</ref>) BJS' 2014 report did not discuss this statistic<ref name="DuroseCensus16">{{cite web |url=https://bjs.ojp.gov/content/pub/pdf/pffclrs14.pdf |format=PDF |title=Publicly Funded Forensic Crime Laboratories: Resources and Services, 2014 |author=Durose, M.R.; Burch, A.M.; Walsh, K.A.; Tiry, E. |publisher=Bureau of Justice Statistics |date=November 2016 |accessdate=14 June 2022}}</ref>, but with the U.S. Drug Enforcement Administration's (DEA's) National Forensic Laboratory Information System (NFLIS) program reporting 88% of labs testing controlled and non-controlled substances secured by law enforcement operations using a LIMS<ref name="NFLISSurv19">{{cite web |url=https://www.nflis.deadiversion.usdoj.gov/DesktopModules/ReportDownloads/Reports/13121NFLISdrugSurveyRpt6Nov29.pdf |archiveurl=https://web.archive.org/web/20210318022453/https://www.nflis.deadiversion.usdoj.gov/DesktopModules/ReportDownloads/Reports/13121NFLISdrugSurveyRpt6Nov29.pdf |format=PDF |title=NFLIS-Drug 2019 Survey of Crime Laboratory Drug Chemistry Sections Report |author=National Forensic Laboratory Information System |publisher=U.S. Drug Enforcement Administration |date=October 2019 |archivedate=18 March 2021 |accessdate=14 June 2022}}</ref>, it appears LIMS adoption by forensics and medical examiners labs is continuing to increase. This is important because the processes within these labs match up well with what a LIMS has to offer, with a LIMS capable of enhancing caseload management, reporting, health data security, evidence control, and more.<ref name="LevyImplem13" /><ref name="NFLISSurv19" /><ref name="BollingerALand20">{{Cite web |author=Bollinger, K.; Salyards, J.; Satcher, R. et al. |title=A Landscape Study of Laboratory Information Management Systems (LIMS) for Forensic Crime Laboratories |url=https://forensiccoe.org/private/5ff49f614eb00 |format=PDF |publisher=Forensic Technology Center of Excellence, U.S. Department of Justice, Office of Justice Programs, National Institute of Justice, Office of Investigative and Forensic Sciences |date=August 2020 |accessdate=13 June 2022}}</ref><ref name="NIJReport19">{{Cite web |author=National Institute of Justice |title=Report to Congress: Needs Assessment of Forensic Laboratories and Medical Examiner/Coroner Offices |url=https://nij.ojp.gov/library/publications/report-congress-needs-assessment-forensic-laboratories-and-medical |publisher=U.S. Department of Justice, Office of Justice Programs, National Institute of Justice |date=December 2019 |accessdate=13 June 2022}}</ref>
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| It's clear that between any two forensics labs, workflows will likely differ, depending on what functions are performed. The 2014 BJS survey found that among publicly funded crime labs, an average of five different forensic functions were performed in or near the lab. The most common activities included identification of drugs and other controlled substances, analysis of biological specimens, analysis of fingerprints, analysis of firearms and toolmarks, and analysis of crime scenes and trace evidence.<ref name="DuroseCensus16" /> Some functions, such as toxicology analysis and forensic biology casework, also get outsourced to other labs, with 38% of publicly funded crime labs outsourcing at least one function in 2014.<ref name="DuroseCensus16" /> This outsourcing, which may occur as a result of increased forensic testing demand or lack of in-house resources inevitably puts the forensic workload on other labs that may not necessarily identify purely as forensics labs, muddying the waters further.
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| Additionally, the workflows of a single lab may change over time as new areas of forensic practice are added to the lab or medical examiners office, requiring additional specialized equipment and LIMS to better manage those new areas of practice.<ref name="NIJReport19" /> The NFLIS, for example, notes that controlled substance testing labs "are constantly dealing with the need to identify and test for new or emerging drugs," requiring reference spectra, standards, procedures validation, and staff who are familiar or can be trained on the new procedures.<ref name="NFLISSurv19" /> It may take time to integrate this sort of new testing into existing workflows; however, a well-maintained configurable LIMS can arguably speed that process along by housing the reference spectra, tracking the inventory of standards, managing the workflows, and documenting staff training on the procedures.
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| Finally, workflows and workload can get modified due to increasing demand for forensic laboratory services, creating backlogs.<ref name="DuroseCensus16" /><ref name="NFLISSurv19" /><ref name="NIJReport19" /> These backlogs may occur at no fault of the lab<ref name="DuroseCensus16" /><ref name="NIJReport19" /> and be in part due to loss of critical staff, an influx of emerging drugs, workload and responsibility increases, lack of funding, and evidence collected for testing that actually doesn't need to be tested.<ref name="NFLISSurv19" /><ref name="NIJReport19" /> Given the state of increasing workloads and backlogs, a LIMS is more important than ever to help improve efficiencies in the laboratory, monitor turnaround times, give insights into backlogs, and better track evidence that doesn't or no longer requires analyses. Of course, as a forensics and medical examiners lab grows and takes on more functions to better meet demand, a highly configurable LIMS also helps integrate those new, related workflows into the dynamics of the lab.
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| ===Base LIMS requirements===
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| Given the above, it's clear LIMS adoption and use must continue in crime labs. But a generic LIMS won't do; it's imperative the lab find a solution that meets all or most its workflow requirements. This more often than not requires a configurable solution that enables trained users to quickly make the changes they need, if those changes make sense within the overall data structure of the LIMS.<ref name="BollingerALand20" />
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| What follows is a list of system functionality important to most any forensics and medical examiner laboratory, with a majority of that functionality found in many vendor software solutions.<ref name="BollingerALand20" /><ref name="NIJReport19" /><ref>{{Cite web |title=Alcestis - Features |url=https://www.alcestis.org/features.htm |publisher=Michigan Public Health Institute |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Medical Examiner System |url=http://www.porterlee.com/mes.html |publisher=Porter Lee Corporation |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=CoronerME - Features |url=https://coronerme.com/features/ |publisher=CoronerME.com |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Next Generation Forensic Case Management |url=https://www.necsws.com/forensic-case-management/ |publisher=NEC Software Solutions UK Limited |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Forensic Filer Online |url=https://www.forensicfiler.com/forensic-filer-online.aspx |publisher=Summit IT Solutions |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Coroner Software Features |url=https://www.coronercasemanager.com/features/ |publisher=Ragefish |accessdate=13 June 2022}}</ref><ref>{{Cite web |date= |title=Forensic Advantage Systems |url=https://caliberpublicsafety.com/forensic-advantage/ |publisher=Harris Computer Systems |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Cohero - Powerful Features |url=https://cohero.com/features/ |publisher=Cohero |accessdate=13 June 2022}}</ref><ref>{{Cite web |title=LIMS-plus |url=https://justicetrax.com/products-and-services/lims-plus/ |publisher=JusticeTrax, Inc |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=QUINCYTECH |url=https://www.quincytech.com |publisher=Quincy Technology Solutions, Inc |accessdate=13 June 2022}}</ref><ref>{{Cite web |last=Douglas, S.E. |date=May 2022 |title=21. Forensic case and data management |work=LIMSpec 2022 R1 |url=https://www.limswiki.org/index.php?title=LII:LIMSpec/Specialty_Laboratory_Functions#21._Forensic_case_and_data_management |publisher=LIMSwiki.org |accessdate=13 June 2022}}</ref> In many cases, those solutions aren't necessarily LIMS but rather "case management systems," "medical examiner systems," "medical case management systems," or "coroner management systems." In the end, however, the features across this spectrum of solution types are relatively similar. In some cases, a LIMS will even incorporate the case management features of these specialty systems.
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| '''Test, sample and case management'''
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| *Sample, property and evidence log-in and management, with support for unique IDs
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| *Support for pre-logging of death and evidence data before physical materials arrive
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| *Body reception, location and disposition support
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| *Barcode and RFID support
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| *End-to-end sample, body, property and evidence tracking
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| *Custom and industry-specific test and method management, including for breath alcohol and sexual assault testing
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| *Test, instrument, subpoena and other event scheduling
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| *Test requesting
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| *Configurable screens and data fields
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| *Analytical tools, including data visualization, statistical analysis and data mining tools
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| *Data import and export
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| *Robust query tools
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| *Document and image management
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| *Workflow management
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| *Case management, including case assignment, reassignment and prioritization, with support for unique and third-party IDs:
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| **Story-related entry for cases
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| **Geolocation capture and support
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| **Mass casualty event support
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| **Cluster and crime scene mapping tools
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| **Mobile and offline data entry support for remote work
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| **Dashboard view of all pertinent information for a case, including criminal case status
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| **Dashboard or other view showing case and test assignment, status, and backlog
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| '''Quality, security and compliance'''
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| *Quality assurance / quality control mechanisms
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| *Standardized terminology via built-in dictionaries and medical classification codes like ICD
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| *National Association of Medical Examiners (NAME) and International Association of Coroners and Medical Examiners (IAC&ME) accreditation support
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| *Results review and approval
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| *User qualification, performance and training management
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| *Audit trails and chain of custody support
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| *Configurable and granular role-based security
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| *Configurable system access and use (log-in requirements, account usage rules, account locking, etc.)
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| *Electronic signature support
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| *Data encryption and secure communication protocols
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| *Archiving and retention of case and other data and information
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| *Configurable data backups
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| *Status updates and alerts
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| '''Operations management and reporting'''
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| *Customizable rich-text reporting, with multiple supported output formats
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| *Custom and industry-specific forms, including body release, autopsy authorization, media release, cremation authorization, subpoena, etc.
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| *Support for state-specific death certificates
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| *Industry-compliant labeling
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| *Email integration
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| *Instrument interfacing and data management
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| *Instrument calibration and maintenance tracking
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| *Inventory and reagent management
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| *Third-party software and database interfacing
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| *Integrated (or online) system help
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| *Hour, mileage, and expense tracking
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| *Turnaround time calculation
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| ===Specialty LIMS requirements===
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| As noted previously, the DOJ points out many disciplines that are used in and near the forensics laboratory.<ref name=":0" /> It is beyond the scope of this article to address the system functionality for every single discipline. However, an attempt has been made to cover the most important disciplines and sub-disciplines associated with forensics and medical examiners labs in regards to LIMS functionality.
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| ====Forensic pathology and histology====
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| The workflows of a forensic pathology and histology (or histopathology) lab tend to be marginally different from their purely clinical counterpart. However, there will be many similarities with clinical information solutions like a [[laboratory information system]] (LIS) designed to manage clinical pathology and histology workflows. That said, in addition to the base functionality above, a LIMS that addresses forensic pathology and histology will still need to address (or allow users to)<ref>{{Cite journal |last=Lau |first=Gilbert |last2=Lai |first2=Siang Hui |date=2008 |title=Forensic Histopathology |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7122801/ |journal=Forensic Pathology Reviews |volume=5 |pages=239–265 |doi=10.1007/978-1-59745-110-9_13 |pmc=7122801}}</ref><ref>{{Cite web |date=2022 |title=Healthcare - Anatomic Pathology |url=https://www.labware.com/industries/healthcare#anatomic |publisher=LabWare, Inc |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=Sunquest CoPathPlus |url=https://www.sunquestinfo.com/software-and-services/copathplus/ |publisher=CliniSys Group Limited |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2021 |title=NovoPath 360 |url=https://www.novopath.com/ |publisher=NovoPath, Inc |accessdate=13 June 2022}}</ref><ref>{{Cite web |date=2022 |title=TD HistoCyto |url=https://www.technidata-web.com/en-gb/solutions-services/solutions/histopathology |publisher=Technidata SAS |accessdate=13 June 2022}}</ref><ref name="PromadisForensic">{{cite web |url=http://www.promadis.com/go/our-products/forensic-science-lims |title=Forensic Science LIMS |publisher=Promadis Pty. Ltd |date=2022 |accessdate=14 June 2022}}</ref>:
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| *Configure the system using templates for histology and cytology case types
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| *Add, view and link pre-generated organ maps and other diagrams
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| *Add, view and link custom annotated pathology imaging
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| *Support blocks and slides, as well as whole organs, as specimens, with predefined descriptions
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| *Document grossing examinations
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| *Print slides and cassettes
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| *Provide case management, reporting and test requisition
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| *Provide specialty workflow for autopsy
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| *Provide stain panels and histology worksheets
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| *Support shared management of tissue samples among departments
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| *Support polymerase chain reaction (PCR) workflow and reporting
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| *Support pathology-specific reflex testing
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| *Create a preliminary findings report for the coroner
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| ====Forensic neuropathology====
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| Forensic neuropathology takes many of the aspects of forensic pathology and narrows them down to examinations of the brain and its corresponding structures in the medico-legal context. As such, a forensic LIMS will need to allow users to better perform and manage examinations of head injuries, spinal injuries, infections. and neurological conditions.<ref>{{Cite book |date=2021 |editor-last=Whitwell |editor-first=Helen L. |editor2-last=Milroy |editor2-first=Christopher |editor3-last=Du Plessis |editor3-first=Daniel |title=Forensic neuropathology |edition=Second edition |publisher=CRC Press |place=Boca Raton |isbn=978-1-4987-0616-2}}</ref><ref>{{Cite book |date=2007 |editor-last=Itabashi |editor-first=Hideo H. |title=Forensic neuropathology: a practical review of the fundamentals |url=https://www.worldcat.org/title/mediawiki/oclc/ocm84612004 |publisher=Elsevier/Academic Press |place=Amsterdam ; Boston |isbn=978-0-12-058527-4 |oclc=ocm84612004}}</ref><ref>{{Cite web |last=Schmidt Case, M.E. |date=18 October 2016 |title=Forensic Neuropathology |work=Medscape |url=https://emedicine.medscape.com/article/1680207-overview |publisher=WebMD, LLC |accessdate=14 June 2022}}</ref> This means, in addition to base LIMS and pathology LIMS functionality, forensic neuropathologists need a forensics LIMS that:
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| *Comes with pre-configured tests, templates, and case forms specific to neuropathology
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| *Fully supports imaging applications and management, typical to forensic neuropathology practice
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| *Fully supports a variety of standardized image formats with large file sizes
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| ====Forensic toxicology====
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| A 2017 report by NFLIS indicated that among medical examiner/coroner offices surveyed, 96% of them outsourced their toxicology work to an off-site or reference toxicology lab.<ref name="NFLISMedEx18">{{cite web |url=https://www.nflis.deadiversion.usdoj.gov/nflisdata/docs/NFLIS-MECSurveyReport.pdf |format=PDF |title=2017 Medical Examiner/Coroner Office Survey Report |author=National Forensic Laboratory Information System |publisher=U.S. Drug Enforcement Administration |date=August 2018 |accessdate=14 June 2022}}</ref> As such, the toxicology functionality of a forensics LIMS may be of more importance to forensic crime labs than medical examiners offices. That said, such a LIMS should assist the lab with a variety of toxicology, chemistry, and pharmacology test methods. In addition to the base features of a forensics LIMS, the forensic toxicology lab will ask their LIMS to<ref name="PromadisForensic" /><ref name="APEasyFeatures20">{{cite web |url=https://easytoxicology.com/features/ |archiveurl=https://web.archive.org/web/20201028074209/https://easytoxicology.com/features/ |title=Easytox: Features |publisher=AP Easy Software Solutions |date=2020 |archivedate=28 October 2020 |accessdate=14 June 2022}}</ref><ref name="DataUnlimitedLIMSSol20">{{cite web |url=http://www.duii.com/products/starfruit-toxicology/ |title=Starfruit Toxicology |publisher=Data Unlimited International, Inc |date=2017 |accessdate=14 June 2022}}</ref><ref name="LabLynxToxicology20">{{cite web |url=https://www.lablynx.com/industries/forensics/toxicology-lims/ |title=Toxicology LIMS |publisher=LabLynx, Inc |date=2022 |accessdate=14 June 2022}}</ref><ref name="DTPMOnlineData20">{{cite web |url=https://www.dtpm.com/online-data-management/ |title=Online Data Management |publisher=DTPM, Inc |date=2022 |accessdate=14 June 2022}}</ref><ref name="OrchardPain20">{{cite web |url=https://www.orchardsoft.com/solutions/pain-management-toxicology-labs/ |title=Pain Management & Toxicology Labs |publisher=Orchard Software Corporation |date=2022 |accessdate=14 June 2022}}</ref>:
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| *Support industry-specific drug, alcohol, chemical (e.g., ethylene glycol) and gas (e.g., carbon monoxide) testing
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| *Support customizable drug panels and tests
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| *Provide management for compounds and compound grouping
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| *Provide toxicology-specific reporting formats supporting best practices
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| *Support the management of drug court cases associated with testing
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| *Provide trend monitoring
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| ====Forensic DNA and molecular testing====
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| Like molecular and genetic diagnostics (i.e., its clinical counterpart), forensic molecular biology turns to a number of chemical, immunological, microscopic, and physical methods for extracting and interpreting DNA and other genetic materials. A wide array of methods encompass these activities, demanding a LIMS that is capable of managing the workflows and tools that assist the forensic molecular biologist. Along with the base LIMS functionality described prior, the forensic molecular biology lab will require its LIMS to<ref>{{Cite journal |last=Gunn |first=Peter |last2=Walsh |first2=Simon |last3=Roux |first3=Claude |date=2014-03-05 |title=The nucleic acid revolution continues – will forensic biology become forensic molecular biology? |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3942684/ |journal=Frontiers in Genetics |volume=5 |doi=10.3389/fgene.2014.00044 |issn=1664-8021 |pmc=3942684 |pmid=24634675}}</ref><ref name="SunquestMitogen20">{{cite web |url=https://www.sunquestinfo.com/software-and-services/lims/ |title=Sunquest Mitogen LIMS |publisher=Sunquest Information Systems, Inc |date=2022 |accessdate=14 June 2022}}</ref><ref name="XifinMolec20">{{cite web |url=https://www.xifin.com/industry-solutions/laboratory/molecular-diagnostics |title=Molecular Diagnostics |publisher=XIFIN, Inc |date=2021 |accessdate=14 June 2022}}</ref><ref name="PsycheNucleoLIS20">{{cite web |url=https://psychesystems.com/enterprise-laboratory-information-software/nucleolis-molecular-lab-testing-software/ |title=NucleoLIS - Flexible & Modern LIS |publisher=Psyche Systems |date=2022 |accessdate=14 June 2022}}</ref><ref name="MyersLab18">{{cite journal |title=Laboratory Information Systems and Instrument Software Lack Basic Functionality for Molecular Laboratories |journal=Journal of Molecular Diagnostics |author=Myers, C.; Swadley, M.; Carter, A.B. |volume=20 |issue=5 |pages=591–99 |year=2018 |doi=10.1016/j.jmoldx.2018.05.011}}</ref><ref name="NYCForensic">{{cite web |url=https://www1.nyc.gov/site/ocme/services/technical-manuals.page |title=Forensic Biology Manuals |publisher=NYC of Chief Medical Examiner, Department of Forensic Biology |date=2022 |accessdate=14 June 2022}}</ref><ref>{{Cite journal |last=Coble |first=Michael D. |last2=Bright |first2=Jo-Anne |date=2019-01 |title=Probabilistic genotyping software: An overview |url=https://linkinghub.elsevier.com/retrieve/pii/S1872497318305520 |journal=Forensic Science International: Genetics |language=en |volume=38 |pages=219–224 |doi=10.1016/j.fsigen.2018.11.009}}</ref>:
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| *Support common testing for molecular biology, including methods and protocols for serology, short tandem repeat (STR) analyses and mitochondrial DNA analyses
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| *Provide customized workflows for molecular and next-generation sequencing (NGS) testing, including FISH, PCR, gel electrophoresis, cytogenetics and more
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| *Manage sample collection kits
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| *Track sample and aliquot lineage for cell lines, tissues, slides, etc.
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| *Track nucleic acid quantity and quality of samples or specimens
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| *Connect with third-party analytical software systems, e.g., probabilistic genotyping software
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| *Provide cleanly formatted rich-text reports customized for molecular diagnostics
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| ====Forensic anthropology and entomology====
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| Given the specialized studies involved in these fields, any forensic LIMS will need to address the additional requirements they demand. In the case of forensic anthropology, in addition to base functionality, the LIMS needs to<ref name="UoNRenoForensicAnth">{{cite web |url=https://www.unr.edu/anthropology/research-and-facilities/forensic-anthropology-and-bioarchaeology-laboratory |title=Forensic Anthropology and Bioarchaeology Laboratory |publisher=University of Nevada, Reno |accessdate=14 June 2022}}</ref><ref name="NMNHWritten">{{cite web |url=https://naturalhistory.si.edu/education/teaching-resources/written-bone/forensic-anthropology |title=Written in Bone: Forensic Anthropology |author=National Museum of Natural History |publisher=Smithsonian |accessdate=14 June 2022}}</ref>:
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| *Support high-resolution radiographic imaging
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| *Support the workflows and methods of analyzing bones and other hard remains
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| For the forensic entomology LIMS, it should<ref>{{Cite journal |last=Ferro |first=Michael L. |last2=Summerlin |first2=Morgan |date=2019-07-08 |title=Developing a standardized list of entomological collection methods for use in databases |url=https://zookeys.pensoft.net/article/32347/ |journal=ZooKeys |volume=861 |pages=145–156 |doi=10.3897/zookeys.861.32347 |issn=1313-2970 |pmc=PMC6629709 |pmid=31333330}}</ref><ref>{{Cite journal |last=Stucky |first=Brian |last2=Balhoff |first2=James |last3=Barve |first3=Narayani |last4=Barve |first4=Vijay |last5=Brenskelle |first5=Laura |last6=Brush |first6=Matthew |last7=Dahlem |first7=Gregory |last8=Gilbert |first8=James |last9=Kawahara |first9=Akito |last10=Keller |first10=Oliver |last11=Lucky |first11=Andrea |date=2019-03-13 |title=Developing a vocabulary and ontology for modeling insect natural history data: example data, use cases, and competency questions |url=https://bdj.pensoft.net/article/33303/ |journal=Biodiversity Data Journal |volume=7 |pages=e33303 |doi=10.3897/BDJ.7.e33303 |issn=1314-2828 |pmc=PMC6426826 |pmid=30918448}}</ref><ref>{{Cite journal |last=Amendt |first=Jens |last2=Campobasso |first2=Carlo P. |last3=Gaudry |first3=Emmanuel |last4=Reiter |first4=Christian |last5=LeBlanc |first5=Hélène N. |last6=J. R. Hall |first6=Martin |date=2007-03 |title=Best practice in forensic entomology—standards and guidelines |url=http://www.eafe.org/Members_area_files/Best%20Practise.pdf |journal=International Journal of Legal Medicine |language=en |volume=121 |issue=2 |pages=90–104 |doi=10.1007/s00414-006-0086-x |issn=0937-9827}}</ref><ref>{{Cite journal |last=Matuszewski |first=Szymon |date=2021-04-01 |title=Post-Mortem Interval Estimation Based on Insect Evidence: Current Challenges |url=https://www.mdpi.com/2075-4450/12/4/314 |journal=Insects |language=en |volume=12 |issue=4 |pages=314 |doi=10.3390/insects12040314 |issn=2075-4450 |pmc=PMC8066566 |pmid=33915957}}</ref><ref>{{Cite journal |last=Lutz |first=Lena |last2=Verhoff |first2=Marcel A. |last3=Amendt |first3=Jens |date=2021-02-09 |title=To Be There or Not to Be There, That Is the Question—On the Problem of Delayed Sampling of Entomological Evidence |url=https://www.mdpi.com/2075-4450/12/2/148 |journal=Insects |language=en |volume=12 |issue=2 |pages=148 |doi=10.3390/insects12020148 |issn=2075-4450 |pmc=PMC7915408 |pmid=33572161}}</ref><ref>{{Cite journal |last=Hall |first=Martin J. R. |date=2021-02-17 |title=The Relationship between Research and Casework in Forensic Entomology |url=https://www.mdpi.com/2075-4450/12/2/174 |journal=Insects |language=en |volume=12 |issue=2 |pages=174 |doi=10.3390/insects12020174 |issn=2075-4450 |pmc=PMC7922124 |pmid=33671186}}</ref>
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| * Provide consistent terminology for insects and their capture methods
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| * Offer workflow support in-line with standardized forensic entomology methods
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| * Provide sample management and tracking functionality that reduces insect evidence collection errors and provides environmental monitoring of corpse temperatures
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| * Be able to differentiate between research activities and casework while still allowing for mining of both types of data and information
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| ==References==
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| {{Reflist|colwidth=30em}}
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| <!---Place all category tags here-->
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| [[Category:LIMS FAQ:Forensics]]
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| [[Category:LIMS FAQ:Guides, white papers, and other publications]]
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Template:Short description
"LOQ" redirects here. For the company listed as LOQ on the London Stock Exchange, see
Lo-Q. For the airport in Botswana with
IATA code LOQ, see
Lobatse Airport.
The limit of detection (LOD or LoD) is the lowest signal, or the lowest corresponding quantity to be determined (or extracted) from the signal, that can be observed with a sufficient degree of confidence or statistical significance. However, the exact threshold (level of decision) used to decide when a signal significantly emerges above the continuously fluctuating background noise remains arbitrary and is a matter of policy and often of debate among scientists, statisticians and regulators depending on the stakes in different fields.
Significance in analytical chemistry
In analytical chemistry, the detection limit, lower limit of detection, also termed LOD for limit of detection or analytical sensitivity (not to be confused with statistical sensitivity), is the lowest quantity of a substance that can be distinguished from the absence of that substance (a blank value) with a stated confidence level (generally 99%).[1][2][3] The detection limit is estimated from the mean of the blank, the standard deviation of the blank, the slope (analytical sensitivity) of the calibration plot and a defined confidence factor (e.g. 3.2 being the most accepted value for this arbitrary value).[4] Another consideration that affects the detection limit is the adequacy and the accuracy of the model used to predict concentration from the raw analytical signal.[5]
As a typical example, from a calibration plot following a linear equation taken here as the simplest possible model:
![{\displaystyle f(x)=ax+b}](https://en.wikipedia.org/api/rest_v1/media/math/render/svg/75c655df4be41082c4bba924beab2c1dc27d019c)
where,
corresponds to the signal measured (e.g. voltage, luminescence, energy, etc.), "Template:Mvar" the value in which the straight line cuts the ordinates axis, "Template:Mvar" the sensitivity of the system (i.e., the slope of the line, or the function relating the measured signal to the quantity to be determined) and "Template:Mvar" the value of the quantity (e.g. temperature, concentration, pH, etc.) to be determined from the signal
,[6] the LOD for "Template:Mvar" is calculated as the "Template:Mvar" value in which
equals to the average value of blanks "Template:Mvar" plus "Template:Mvar" times its standard deviation "Template:Mvar" (or, if zero, the standard deviation corresponding to the lowest value measured) where "Template:Mvar" is the chosen confidence value (e.g. for a confidence of 95% it can be considered Template:Mvar = 3.2, determined from the limit of blank).[4]
Thus, in this didactic example:
![{\displaystyle {\text{LOD for }}x={\frac {\left(f(x)-b\right)}{a}}={\frac {\left(y+3.2s-b\right)}{a}}}](https://en.wikipedia.org/api/rest_v1/media/math/render/svg/cefb2c50b28fcf177101091bd86aa50f3eac16c8)
There are a number of concepts derived from the detection limit that are commonly used. These include the instrument detection limit (IDL), the method detection limit (MDL), the practical quantitation limit (PQL), and the limit of quantitation (LOQ). Even when the same terminology is used, there can be differences in the LOD according to nuances of what definition is used and what type of noise contributes to the measurement and calibration.[7]
The figure below illustrates the relationship between the blank, the limit of detection (LOD), and the limit of quantitation (LOQ) by showing the probability density function for normally distributed measurements at the blank, at the LOD defined as 3 × standard deviation of the blank, and at the LOQ defined as 10 × standard deviation of the blank. (The identical spread along Abscissa of these two functions is problematic.) For a signal at the LOD, the alpha error (probability of false positive) is small (1%). However, the beta error (probability of a false negative) is 50% for a sample that has a concentration at the LOD (red line). This means a sample could contain an impurity at the LOD, but there is a 50% chance that a measurement would give a result less than the LOD. At the LOQ (blue line), there is minimal chance of a false negative.
Template:Wide image
Instrument detection limit
Most analytical instruments produce a signal even when a blank (matrix without analyte) is analyzed. This signal is referred to as the noise level. The instrument detection limit (IDL) is the analyte concentration that is required to produce a signal greater than three times the standard deviation of the noise level. This may be practically measured by analyzing 8 or more standards at the estimated IDL then calculating the standard deviation from the measured concentrations of those standards.
The detection limit (according to IUPAC) is the smallest concentration, or the smallest absolute amount, of analyte that has a signal statistically significantly larger than the signal arising from the repeated measurements of a reagent blank.
Mathematically, the analyte's signal at the detection limit (
) is given by:
![{\displaystyle S_{dl}=S_{reag}+3\ \sigma _{reag}}](https://en.wikipedia.org/api/rest_v1/media/math/render/svg/3f9018305372aed953566b73c0012e6de76b3084)
where,
is the mean value of the signal for a reagent blank measured multiple times, and
is the known standard deviation for the reagent blank's signal.
Other approaches for defining the detection limit have also been developed. In atomic absorption spectrometry usually the detection limit is determined for a certain element by analyzing a diluted solution of this element and recording the corresponding absorbance at a given wavelength. The measurement is repeated 10 times. The 3σ of the recorded absorbance signal can be considered as the detection limit for the specific element under the experimental conditions: selected wavelength, type of flame or graphite oven, chemical matrix, presence of interfering substances, instrument... .
Method detection limit
Often there is more to the analytical method than just performing a reaction or submitting the analyte to direct analysis. Many analytical methods developed in the laboratory, especially these involving the use of a delicate scientific instrument, require a sample preparation, or a pretreatment of the samples prior to being analysed. For example, it might be necessary to heat a sample that is to be analyzed for a particular metal with the addition of acid first (digestion process). The sample may also be diluted or concentrated prior to analysis by means of a given instrument. Additional steps in an analysis method add additional opportunities for errors. Since detection limits are defined in terms of errors, this will naturally increase the measured detection limit. This "global" detection limit (including all the steps of the analysis method) is called the method detection limit (MDL). The practical way for determining the MDL is to analyze seven samples of concentration near the expected limit of detection. The standard deviation is then determined. The one-sided Student's t-distribution is determined and multiplied versus the determined standard deviation. For seven samples (with six degrees of freedom) the t value for a 99% confidence level is 3.14. Rather than performing the complete analysis of seven identical samples, if the Instrument Detection Limit is known, the MDL may be estimated by multiplying the Instrument Detection Limit, or Lower Level of Detection, by the dilution prior to analyzing the sample solution with the instrument. This estimation, however, ignores any uncertainty that arises from performing the sample preparation and will therefore probably underestimate the true MDL.
Limit of each model
The issue of limit of detection, or limit of quantification, is encountered in all scientific disciplines. This explains the variety of definitions and the diversity of juridiction specific solutions developed to address preferences. In the simplest cases as in nuclear and chemical measurements, definitions and approaches have probably received the clearer and the simplest solutions. In biochemical tests and in biological experiments depending on many more intricate factors, the situation involving false positive and false negative responses is more delicate to handle. In many other disciplines such as geochemistry, seismology, astronomy, dendrochronology, climatology, life sciences in general, and in many other fields impossible to enumerate extensively, the problem is wider and deals with signal extraction out of a background of noise. It involves complex statistical analysis procedures and therefore it also depends on the models used,[5] the hypotheses and the simplifications or approximations to be made to handle and manage uncertainties. When the data resolution is poor and different signals overlap, different deconvolution procedures are applied to extract parameters. The use of different phenomenological, mathematical and statistical models may also complicate the exact mathematical definition of limit of detection and how it is calculated. This explains why it is not easy to come to a general consensus, if any, about the precise mathematical definition of the expression of limit of detection. However, one thing is clear: it always requires a sufficient number of data (or accumulated data) and a rigorous statistical analysis to render better signification statistically.
Limit of quantification
The limit of quantification (LoQ, or LOQ) is the lowest value of a signal (or concentration, activity, response...) that can be quantified with acceptable precision and accuracy.
The LoQ is the limit at which the difference between two distinct signals / values can be discerned with a reasonable certainty, i.e., when the signal is statistically different from the background. The LoQ may be drastically different between laboratories, so another detection limit is commonly used that is referred to as the Practical Quantification Limit (PQL).
See also
References
Further reading
- "Limits for qualitative detection and quantitative determination. Application to radiochemistry". Analytical Chemistry 40 (3): 586–593. 1968. doi:10.1021/ac60259a007. ISSN 0003-2700.
External links
Template:BranchesofChemistry
Template:Authority control