The SensiTox C. difficile Toxin Test is an immunofluorescence assay intended for the qualitative detection of Clostridioides difficile toxins A and/or B in human stool specimens. The test is intended as an aid in the diagnosis of C. difficile infection (CDI) in patients exhibiting symptoms of CDI. Negative results do not preclude toxigenic C. difficile infection. The SensiTox C. difficile Toxin Test should not be used as the sole basis for treatment or other management decisions. The test can only be used with the MultiPath platform.

Device Description

The SensiTox C. difficile Toxin Test detects toxins A and B in stool samples using an immunofluorescence assay and the proprietary MultiPath detection technology. The assay is performed on the proprietary MultiPath Analyzer. A stool sample is added to Stool Specimen Diluent, processed through a spin column, and the filtrate is added to the SensiTox C. difficile Cartridge. The Cartridge is loaded onto the MultiPath Analyzer for processing. The Analyzer reads barcodes, heats the cartridge, splits the sample into aliquots, mixes with antibody conjugated fluorescent and magnetic particles, and incubates. Magnetic particles and tethered fluorescent particles are drawn to the bottom imaging surface by magnets and imaged and quantified using non-magnified digital imaging. Results are interpreted by the MultiPath applications software.

AI/ML Overview

Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided text:

Device: SensiTox C. difficile Toxin Test

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implied by the performance metrics reported, as these are the benchmarks the device aims to meet.

Performance Metric	Acceptance Criteria (Implied)	Reported Device Performance
Limit of Detection (LoD)	Detection rate ≥95% at specified concentrations for Toxins A and B	Toxin A LoD: 3.5 ng/mLToxin B LoD: 50 ng/mL
Reproducibility (Overall)	High reproducibility (implied by 99.2% accuracy reported)	99.2% (373 correct results out of 376 total samples)
Reproducibility (Negative Samples)	High accuracy for negative samples	98.9% (89/90 correct)
Reproducibility (Low Positive Samples)	High accuracy for low positive samples	98.9% (89/90 correct)
Reproducibility (Moderate Positive Samples)	High accuracy for moderate positive samples	98.9% (89/90 correct)
Reproducibility (High Positive Samples)	High accuracy for high positive samples	100% (100/100 correct)
Analytical Reactivity (Inclusivity)	Ability to detect multiple ribotypes of toxins A and B	All 6 tested toxin A ribotypes detectedAll 8 tested toxin B ribotypes detected
Analytical Specificity	No cross-reactivity with common organisms; no negative interference from common organisms on toxin detection	None of 31 tested organisms cross-reacted.None of 31 tested organisms interfered with toxin A/B detection (except Vancomycin at 50 mg/mL).
Interfering Substances	No negative impact on performance from specified substances at tested concentrations	None of 13 tested substances negatively impact performance at specified concentrations (except Vancomycin at 50 mg/mL).
Clinical Sensitivity	High sensitivity (benchmark not explicitly stated, but 90.6% is achieved)	90.6% [95% CI: 83.1% - 95.0%]
Clinical Specificity	High specificity (benchmark not explicitly stated, but 95.7% is achieved)	95.7% [95% CI: 94.2% - 96.8%]
Positive Predictive Value (PPV)	(Benchmark not explicitly stated)	68.0% [95% CI: 59.5% - 75.4%]
Negative Predictive Value (NPV)	(Benchmark not explicitly stated)	99.0% [95% CI: 98.1% - 99.5%]

2. Sample Size Used for the Test Set and Data Provenance

Clinical Study Test Set Sample Size: 1046 human stool specimens.
Data Provenance: Prospective clinical study performed at three geographically diverse sites in the US. The samples were "left over de-identified, unpreserved, stool specimens from patients suspected of having C. difficile infection." This indicates a prospective collection for the purpose of the study, though using "left over" specimens.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This information is not provided in the document. The ground truth for the clinical study was established by the Cellular Cytotoxicity Neutralization Assay (CCNA), which is a laboratory method, not human expert interpretation.

4. Adjudication Method for the Test Set

This information is not applicable as the ground truth was established by a laboratory assay (CCNA), not by human adjudication of clinical images or interpretations.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs Without AI Assistance

This information is not applicable. The SensiTox C. difficile Toxin Test is an in vitro diagnostic device that directly detects toxins in stool samples using an immunofluorescence assay run on an automated analyzer. It is not an AI-assisted imaging device or a tool that directly assists human readers/interpreters in a diagnostic workflow where their performance would be measured with and without AI.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, the performance data presented is for the device operating in a standalone capacity (algorithm only). The MultiPath Analyzer interprets the results using its applications software, reporting "toxin detected" or "toxin not detected" automatically. There is no human interpretative step described for the SensiTox C. difficile Toxin Test's output.

7. The Type of Ground Truth Used

Bench Studies (LoD, Reproducibility, Analytical Reactivity, Analytical Specificity, Interfering Substances): The ground truth was established using known spiked samples (purified toxins, cultured organisms, interfering substances) in negative pooled stool.
Clinical Performance Evaluation: The ground truth was established by the Cellular Cytotoxicity Neutralization Assay (CCNA). CCNA is a traditional laboratory method for detecting C. difficile toxins and is considered a gold standard for toxin activity.

8. The Sample Size for the Training Set

This information is not provided in the document. The document describes a "test set" for clinical performance evaluation but does not specify a separate "training set" with its sample size for the development of the device's analytical interpretation software. Given this is an in vitro diagnostic device, the "training" would likely involve optimizing the assay chemistry and the MultiPath Analyzer's ability to detect the fluorescent signals, rather than a machine learning model trained on a large dataset of patient samples.

9. How the Ground Truth for the Training Set Was Established

Since the document does not mention a distinct "training set" in the context of machine learning, the establishment of ground truth for any internal development or optimization of the device would implicitly involve the same methods used for the bench studies: controlled experiments with known concentrations of purified toxins and known negative samples, and potentially comparisons to established laboratory methods like CCNA during early development. The document focuses on the validation studies, not necessarily the development phase details.

Summary

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July 8, 2021

First Light Diagnostics, Inc. % Fran White President, Regulatory Affairs MDC Associates, LLC 180 Cabot Street Beverly, Massachusetts 01915

Re: K193490

Trade/Device Name: SensiTox C. difficile Toxin Test Regulation Number: 21 CFR 866.2660 Regulation Name: Microorganism Differentiation And Identification Device Regulatory Class: Class I Product Code: LLH Dated: December 16, 2019 Received: December 17, 2019

Dear Fran White:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part

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801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4. Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Ribhi Shawar, Ph.D. (ABMM) Chief. General Bacteriology and Antimicrobial Susceptibility Branch Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K193490

Device Name SensiTox C. difficile Toxin Test

Indications for Use (Describe)

Type of Use (Select one or both, as applicable)
Prescription Use (Part 21 CFR 801 Subpart D)	Over-The-Counter Use (21 CFR 801 Subpart C)

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2.0 510(k) SUMMARY

Date of Summary:	June 30, 2021
Product Name:	SensiTox™ C. difficile Toxin Test
Sponsor:	First Light Diagnostics2 Omni WayChelmsford, MA 01824
Correspondent:	MDC Associates, Inc.Fran White, President Regulatory Affairs180 Cabot StreetBeverly, MA 01915Phone: (978) 927 3808Fax: (866) 540 3448Email: regulatory@mdcassoc.com
Common Name:	Microorganism differentiation and identification device
Regulation Number:	866.2660
Classification:	LLH, Class I

Substantial Equivalency

Description	First Light DiagnosticsSubject DeviceSensiTox C. difficile Toxin Test	Meridian Bioscience, Inc.Predicate DeviceK041003ImmunoCard® Toxins A & B
Regulation	866.2660	Same
Product Code	LLH	Same
Device Class	Class I	Same
Panel	83 Microbiology	Same
Intended Use	The SensiTox C. difficile Toxin Test is animmunofluorescence assay intended for thequalitative detection of Clostridioides difficiletoxins A and/or B in human stool specimens.The test is intended as an aid in the diagnosisof C. difficile infection (CDI) in patientsexhibiting symptoms of CDI. Negative resultsdo not preclude toxigenic C. difficile infection.The SensiTox C. difficile Toxin Test should notbe used as the sole basis for treatment orother management decisions. The test canonly be used with the MultiPath platform.	ImmunoCard® Toxins A & B is a rapid, qualitative,horizontal-flow enzyme immunoassay (EIA) fordetecting Clostridium difficile toxins A and B inhuman stool. This assay is used as an aid in thediagnosis of C. difficile-associated disease.

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Description	First Light DiagnosticsSubject DeviceSensiTox C. difficile Toxin Test	Meridian Bioscience, Inc.Predicate DeviceK041003ImmunoCard® Toxins A & B
Similarities
Sample Type	Human Stool	Same
Analyte	Toxin A and B	Same
Prescription Required?	Prescription use only	Same
Setting	Clinical laboratory	Same
Differences
Technology	Immunofluorescent assay	Enzyme immunoassay
Antibodies	Detection & Capture: Mouse monoclonalanti-toxin A and B	Goat polyclonal anti-toxin B
Test format	Fluidic cartridge with direct digital imaging	Lateral flow with visual interpretation

Intended Use

Limitations

For prescription use only. Please refer to the SensiTox C. difficile Toxin Test labeling for a more complete list of warnings, precautions, and contraindications.

Methodology

A stool sample, collected in a dry, clean, and leakproof collection media, is used for the test. The stool sample is added to Stool Specimen Diluent containing Protessed manually through a spin column to remove particulates. The stool filtrate is added to the SensiTox C. difficile Cartridge, a single use consumable that contains all the reagents required to run a single test. The Cartridge is loaded onto the MultiPath Analyzer for processing through the steps of the assay.

Once loaded onto the Analyzer, the barcodes on the Cartridge that identify the test type and associated test specific information (manufacturer installed barcode) and sample (laboratory affixed barcode) are read. The cartridge is moved to the fluidics station where it is first heated to 35°C. The sample is then split into 6 equal aliquots in 6 distribution wells within the cartridge, 3 wells specific to toxin B. The sample aliquots flow from the distribution wells to the reagent wells containing target specific antibody conjugated fluorescent and magnetic particles in the form of lyophilized beads. Upon contact with the sample, the lyophilized beads rehydrate and the reaction mixtures flow into the imaging wells, the bottoms of which are coated with a dye cushion reagent. Upon contact with the reagents, the dyecushion dissolves forming a dense opaque aqueous layer that separates the sample and reagents from the bottom optical

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surface of the Imaging Well. In the upper assay layer, the toxins, if present, bind to the magnetic and fluorescent particles tethering them together. The cartridge is incubated for 28 minutes to allow the reaction to take place and then is moved to the magnetics station. At the magnetics station, the imaging well is placed over permanent magnets that draw the magnetic particles and any fluorescent particles that are tethered to them via the target molecules through the dyecushion layer, depositing them on the bottom imaging surface. The captured fluorescent particles are imaged and quantified using non-magnified digitalimaging.

The Analyzer can be run in batch mode or by random access. Up to 20 cartridges can be loaded onto the Analyzer in parallel. The first result is reported in approximately 35 minutes of loading the Analyzer with subsequent results being reported in 2.5 minute increments. The results are interpreted using the MultiPath applications software as valid or invalid, and if valid, the results are reported as toxin detected if either toxin A or B or both toxins are present or toxin not detected if neither toxin is present. Results are displayed on the instrument touch screen and can be printed.

Performance Data: Bench Studies

l. Limit of Detection (LoD)
The limit of detection (LoD) for C. difficile toxins A and B was determined by spiking negative pooled stool with commercially available purified toxins A and B. For each toxin, the LoD is defined as the lowest concentration of target that can be detected at a rate of ≥95%. The LoD was established by testing 5 dilutions of toxins A and B with 3 lots of reagents and 20 replicates per lot for a total of 60 replicates per concentration. The data from the 3 lots were combined to determine the positive hit rate. The LoD established for toxin A is 3.5 ng/mL and for toxin B is 50 ng/mL.
II. Reproducibility
The reproducibility of the SensiTox C. difficile Toxin Test was evaluated at 3 sites over the course of 5 days by 2 operators each day. Randomized and blinded samples comprised of Stool Specimen Diluent spiked with varying concentrations of both toxins A and B – low positive (1-2x LoD), moderate positive (2-4x LoD), high positive (5-8x LoD), and negative (unspiked) were prepared and provided to each participating site. Each operator mixed the designated sample with pooled stool prescreened and known to be negative for toxins A and B and processed the sample using the C. difficile test procedure. A total of 376 samples comprised of 95 negative samples and 281 positive samples was run with an overall reproducibility of 99.2% (Table 2.1). As shown in Table 2.2, the negative sample generated one false positive result and the low and moderate positive samples each generated one false negative result.

Site	Total Samples Run	# Correct Results	# Miscalls	# Invalids	% Accuracy	% Invalid

Site 1	123	123	0	3	100%	2.4%
Site 2	128	127	1	8	99.2%	6.3%
Site 3	125	123	2	5	98.4%	4.0%
Total	376	373	3	16	99.2%	4.3%

Table 2.1 Summary of reproducibility study data

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SampleDescription	Site 1		Site 2		Site 3		Total
	#	%	#	%	#	%	#	%
Negative	30/30	100%	30/30	100%	29/30	96.7%	89/90	98.9%
Low	30/30	100%	29/30	96.7%	30/30	100%	89/90	98.9%
Moderate	30/30	100%	30/30	100%	29/30	96.7%	89/90	98.9%
High	30/30	100%	30/30	100%	30/30	100%	100/100	100%

Table 2.2 Reproducibility data by sample type

III. Analytical Reactivity (Inclusivity)

Analytical reactivity testing was conducted to ensure that the SensiTox C. difficile Toxin Test can detect multiple ribotypes of toxins A and B. Pooled stool samples that were prescreened and confirmed to be negative for toxins A and B were spiked with purified toxin from clinically important ribotypes and tested in the SensiTox C. difficile Toxin Test. Six ribotypes of toxin A were tested at 15 ng/mL and 8 ribotypes of toxin B were tested at 300 pg/mL. Positive controls comprised of toxins A and B purified from the wildtype strain 087 also were tested. The results, summarized in Table 2.3, demonstrate that all toxin A and B ribotypes tested in the SensiTox C. difficile Toxin Test.

ToxinTarget	Ribotype	Toxin A	Toxin B
A	001	Detected	Not Detected
A	002	Detected	Not Detected
A	014	Detected	Not Detected
A	027	Detected	Not Detected
A	078	Detected	Not Detected
A	106	Detected	Not Detected
A	087 (control)	Detected	Not Detected
B	001	Not Detected	Detected
B	001	Not Detected	Detected
B	014	Not Detected	Detected
B	017	Not Detected	Detected
B	027	Not Detected	Detected
B	036	Not Detected	Detected
B	078	Not Detected	Detected
B	106	Not Detected	Detected
B	087 (control)	Not Detected	Detected

Table 2.3 Analytical reactivity of the SensiTox C. difficile Toxin Test

Analytical Specificity IV.

The analytical specificity of the SensiTox C. difficile Toxin Test was evaluated by testing cultured organisms (bacteria, yeast, viruses) in negative pooled stool or contrived stool containing 15 ng/mL of toxin A and 300 pg/mL of toxin B. Bacteria and yeast were tested at a concentration of 1x10 CFU/mL and each virus was tested at a concentration of 1x10 PFU/mL unless otherwise indicated in Table 2.4. All organisms were tested in triplicate in each study.

None of the organisms cross-react when tested in the SensiTox C. difficile Toxin Test. None of the organisms tested in the presence of contrived pooled stool negatively interfere with the detection of toxins A or B.

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Species	ConcentrationTested	Species	ConcentrationTested
Adenovirus	1x105 PFU/mL	Enterovirus	1x105 PFU/mL
Aeromonas hydrophila	1x106 CFU/mL	Escherichia coli	1x106 CFU/mL
Bacillus cereus	1x106 CFU/mL	Escherichia coli sero:0157	1x106 CFU/mL
Bacillus subtilis	1x106 CFU/mL	Escherichia coli type 026:H4	1x106 CFU/mL
Bacteroides fragilis	1x106 CFU/mL	Helicobacter pylori	1x106 CFU/mL
Campylobacter jejuni	1x106 CFU/mL	Klebsiella oxytoca	1x106 CFU/mL
Campylobacter coli	1x106 CFU/mL	Norovirus	7x104 PFU/mL
Candida albicans	1x106 CFU/mL	Peptostreptococcusanaerobius	1x106 CFU/mL
Clostridium difficile (non-toxigenic)	1x106 CFU/mL	Proteus vulgaris	1x106 CFU/mL
Clostridium haemolyticum	1x106 CFU/mL	Pseudomonas aeruginosa	1x106 CFU/mL
Clostridium novyi	1x106 CFU/mL	Rotavirus	1x105 PFU/mL
Clostridium perfringens	1x106 CFU/mL	Salmonella enterica(typhimurium)	1x106 CFU/mL
Clostridium septicum	1x106 CFU/mL	Serratia liquefaciens	1x106 CFU/mL
Clostridium sordellii	1x106 CFU/mL	Shigella dysenteriae	1x106 CFU/mL
Clostridium sporogenes	1x106 CFU/mL	Shigella flexneri	1x106 CFU/mL
Coxsackie-virus	1x105 PFU/mL	Shigella sonnei	1x106 CFU/mL
Cytomegalovirus	1x105 PFU/mL	Staphylococcus aureus	1x106 CFU/mL
Echovirus	4x104 PFU/mL	Staphylococcus epidermidis	1x106 CFU/mL
Enterobacter aerogenes	1x106 CFU/mL	Vibrio cholera	1x106 CFU/mL
Enterobacter cloacae	1x106 CFU/mL	Vibrio parahaemolyticus	1x106 CFU/mL
Enterococcus faecalis	1x106 CFU/mL

Table 2.4 Organisms tested for analytical specificity

4 The potential for purified Clostridium sordellii toxin to cross-react was not evaluated. It is unknown if C. sordellii toxin concentration in the 106 CFU/mL preparation that was tested falls below the limit of detection for the SensiTox C. difficile Toxin Test.

V. Interfering Substances

Negative pooled stool and contrived pooled stool containing 15 ng/mL of toxin A and 300 pg/mL of toxin B were spiked with potential interferents that can be found in stool. The interferents and the concentrations tested are listed in Table 2.5. None of the potential interferents negatively impact the performance of the SensiTox C. difficile Toxin Test, with the exception of Vancomycin. Vancomycin is not inhibitory at 40 mg/mL but was found to negatively impact the detection of toxins A and B at 50 mg/mL.

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Potential Interfering Substance	Highest Concentration Tested and Shownto Not Interfere
Nystatin	500 U/mL (5% w/v)
Barium Sulphate	50 mg/mL(5% w/v)
Hydrocortisone	0.5 mg/mL (5% w/v)
Phenylephrine (Preparation H)	0.1 mg/mL (5% w/v)
Calcium Carbonate (Tums)	10.4 mg/mL (5% w/v)
Aluminum Hydroxide / Magnesium Hydroxide (Sunmark antacid)	1 mg/mL (5% v/v)
Loperamide Hydrochloride (Imodium)	3.3 µg/mL (5% v/v)
Bismuth Subsalicylate (Pepto Bismol)	0.2 mg/mL (5% v/v)
Sennosides (Senokot)	0.6 mg/mL (5% w/v)
Metronidazole in DMSO	50 mg/mL (5% w/v)
Vancomycin	40 mg/mL (4% w/v)
Mucin	50 mg/mL (5% w/v)
DMSO	10% v/v
Whole Blood	40% v/v

Table 2.5 Interferents and concentrations shown to not interfere with test

Clinical Performance Evaluation

The performance of the SensiTox C. difficile Toxin Test was evaluated in a prospective clinical study performed at three geographically diverse sites in the US using left over de-identified, unpreserved, stool specimens from patients suspected of having C. difficile infection. The performance of the test was evaluated in comparison to the cellular cytotoxicity neutralization assay (CCNA).

The overall clinical performance of the SensiTox C. difficile Toxin Test is summarized in Table 2.6 with the data broken down by clinical study site in Table 2.7. The sensitivity of the SensiTox C. difficile Toxin Test is 90.6% and the specificity is 95.7%.

		Cellular Cytotoxicity Neutralization Assay (CCNA)
		Positive	Negative	Total
MultiPath C.difficile Assay	Positive	87	41	128
	Negative	9	909	918
	Total	96	950	1046
Sensitivity [95% CI]		90.6% [83.1% - 95.0%]
Specificity [95% CI]		95.7% [94.2% - 96.8%]
Positive Predictive Value [95% CI]		68.0% [59.5% - 75.4%]
Negative Predictive Value [95% CI]		99.0% [98.1% - 99.5%]

Table 2.6 Summary of clinical performance of SensiTox C. difficile Toxin Test

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SITE	Samples (%)	CCNA Positive (%)	Percent(95% Score Confidence Interval)
			Sensitivity	Specificity
Site 1	343 (32.8%)	28 (8.2%)	89.3% [72.8% - 96.3%]	95.2% [92.3% - 97.1%]
Site 2	449 (42.9%)	42 (9.4%)	85.7% [72.2% - 93.3%]	96.1% [93.7% - 97.6%]
Site 3	254 (24.3%)	26 (10.2%)	100% [87.1% - 100%]	95.6% [92.1% - 97.6%]
Total	1046	96 (9.2%)

Table 2.7 Summary of clinical performance by participating clinical study site

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Regulation Number and Section

§ 866.2660 Microorganism differentiation and identification device.

(a)
Identification. A microorganism differentiation and identification device is a device intended for medical purposes that consists of one or more components, such as differential culture media, biochemical reagents, and paper discs or paper strips impregnated with test reagents, that are usually contained in individual compartments and used to differentiate and identify selected microorganisms. The device aids in the diagnosis of disease.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.