The Trak® Male Fertility Testing System is intended for semi-quantitative assessment of sperm concentration at 15 million sperm per milliliter (M/mL) or below, between 15 and 55 M/mL, and above 55 M/mL. It also provides a qualitative assessment of semen volume.

Sperm concentration and semen volume are only two factors that could impact a man's fertility status and time to pregnancy. For complete assessment of male reproductive health, the user should consult a physician. For in vitro, over the counter home use.

Device Description

The revised Trak® Male Fertility Testing System (Trak) includes a small instrument (the Engine), disposable units in which liquefied semen sample is introduced and the result is interpreted (the Props), and consumables, including Volume Cups and sample droppers.

The Volume Cups are used collect, liquefy, and assess the volume of the semen sample. Markings on the Volume Cup allow the interpretation of volume at/below or above the 1.5 mL threshold. The Trak Engine and Props allow for the semi-quantitative assessments of total sperm concentration: below 15 million/mL, between 15 and 55 million/mL, and above 55 million/mL.

Trak uses the principle of density gradient separation to isolate sperm cells from human semen to provide an estimation of sperm concentration. The Trak Engine spins a test Prop to compact sperm cells within an introduced semen sample into a visible column (or "pellet"). The Prop gives a defined shape to the column, the height of which corresponds to the concentration of sperm cells in the sample. Since semen may also contain cell debris, immature sperm cells, and other contaminant particulates that could contribute to the apparent size of a pellet, it is necessary to filter out the contaminants. Trak achieves this filtering by removing contaminants from view based on density across a predefined liquid density medium.

During operation, approximately 0.17 mL of semen is metered by centrifugal action from the sample inlet into the metering chamber of the Prop. During rotation, the semen floats on "top" of the pre-loaded density medium. Sperm cells pass through the medium due to their high density while contaminants remain floating on the medium. When the spin sequence is complete, the sperm cells form a visible column that is displayed to the user for interpretation. Contaminants that are less dense than the liquid density medium are suspended "above" the medium, substantially separated from the sperm cells and are generally too diffuse to visualize.

AI/ML Overview

This document describes the Trak® Male Fertility Testing System and the studies conducted to establish its performance, particularly focusing on the volume measurement component.

1. Table of Acceptance Criteria and Reported Device Performance

Performance Metric	Acceptance Criteria (Lower Bound of 95% CI)	Reported Device Performance (Lay Subject Interpretation) - Stage 1	Reported Device Performance (Lay Subject Interpretation) - Stage 2
Semen Volume Assessment
Sensitivity	> 80%	97.0% (91.6 – 99.0%)	95.2% (86.9-98.4%)
Specificity	> 80%	95.4% (90.4 – 97.9%)	96.9% (89.3-99.1%)
Overall Percent Agreement (Accuracy)	N/A (implied by sensitivity/specificity)	96.1% (92.8 - 97.9%)	N/A
Sperm Concentration Category (Volume Cup Equivalence)
Correct Categorization Rate	≥ 90%	100% (for both 10 M/mL and 20 M/mL samples)	N/A

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

Semen Volume Assessment (Stage 1 Study: Interpretation of Photographs):
- Sample Size: 232 semen sample photographs.
- Data Provenance: Retrospective (photographs of samples with pre-established reference volumes). The country of origin is not explicitly stated.
Semen Volume Assessment (Stage 2 Study: Interpretation of Simulated Sample in the Volume Cup):
- Sample Size: 127 artificial semen samples (Cups filled with 1 mL, 1.2 mL, or 2 mL).
- Data Provenance: Prospective (simulated samples prepared for the study). The country of origin is not explicitly stated.
Precision of Volume Cup: 75 total replicates for each of 5 artificial semen samples (3 lots, 3 operators, 5 days, 5 replicates each).
Functional Equivalence (Semen Liquefaction): 20 semen sample aliquots from three semen samples.
Functional Equivalence (Trak Sperm Concentration Category Result Equivalence Study): 2 semen pools (10 M/mL and 20 M/mL), tested in 20 replicates for each cup type.
Functional Equivalence (Semen Homogenization Study): Two semen samples formulated to two sperm concentrations differing by more than 50%. 20 aliquots taken from the top and bottom of each cup for each pool.

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

Semen Volume Assessment (Stage 1 & 2): The ground truth was established by a "reference method" (calibrated scale for volume measurement). No specific number or qualifications of human experts for ground truth establishment are provided for these studies. For Stage 1, "trained technicians" also interpreted the photographs, effectively serving as an expert comparison to the lay subjects. Their qualifications are not explicitly detailed beyond being "trained."
Sperm Concentration Category Result Equivalence Study: The ground truth for sperm concentration was established using Computer Assisted Semen Analysis (CASA). The qualifications of CASA operators or the number of such experts are not specified.

4. Adjudication Method for the Test Set

The document primarily describes studies comparing device performance (Lay Subject or Trained Technician interpretation) against a "reference method" (calibrated scale for volume, CASA for concentration). This implies an objective ground truth, rather than an adjudication process between human readers.
For the "Trained Technician vs Lay Subject" comparison in Stage 1, there's a direct comparison, but not an adjudication to establish a single truth; rather, it assesses agreement between these groups.

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

No MRMC comparative effectiveness study involving AI assistance for human readers is described. This device is an over-the-counter home-use system designed for direct user interpretation, not an AI-assisted diagnostic tool for expert human readers.

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

The Trak® Male Fertility Testing System is a device with a visual readout interpreted by the user (human-in-the-loop). There is no description of a standalone algorithm performance without human interpretation. The "Engine" spins the sample, and the "Prop" creates a visible column, but the user "interprets" the column height for concentration and fluid height for volume.

7. The Type of Ground Truth Used

Semen Volume Assessment: The ground truth was established by a "calibrated scale" for direct volume measurement. This is an objective measurement.
Sperm Concentration Category Result Equivalence Study: The ground truth was established using Computer Assisted Semen Analysis (CASA). This is an objective, automated method.
Functional Equivalence Studies (Liquefaction, Homogenization): Ground truth was established by quantitative volume measurements and sperm concentration assessments (presumably by CASA or similar lab methods).

8. The Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of an algorithm or AI. The studies described are validation studies for the device's performance when used by humans. The device itself (Trak Engine and Props) is pre-calibrated and designed, so there isn't a traditional "training set" as understood in machine learning. However, the development and internal testing of the device would have involved samples, but these are not articulated as a distinct "training set" in this context.

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

Since a formal "training set" for an algorithm is not described, the method for establishing its ground truth is not applicable in this document. The ground truth for the validation studies, as detailed in point 7, was established by objective reference methods like calibrated scales and CASA.

Summary

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Image /page/0/Picture/0 description: The image contains the logos of the Department of Health & Human Services and the Food and Drug Administration (FDA). The Department of Health & Human Services logo is on the left, and the FDA logo is on the right. The FDA logo is a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue.

November 17, 2017

Sandstone Diagnostics, Inc. Ulrich Schaff Chief Technology Officer 6111 Southfront Road, Suite J Livermore, California 94551

Re: K172514

Trade/Device Name: Trak Plus Male Fertility Testing System Regulation Number: 21 CFR 864.5220 Regulation Name: Automated differential cell counter Regulatory Class: Class II Product Code: POV Dated: August 18, 2017 Received: August 21, 2017

Dear Ulrich Schaff:

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. 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 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR

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Part 820); 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 http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). 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 (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Leonthena R. Carrington -S

Lea Carrington Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K172514

Device Name Trak® Male Fertility Testing System

Indications for Use (Describe)

Type of Use (Select one or both, as applicable)
-------------------------------------------------

Prescription Use (Part 21 CFR 801 Subpart D)

|X | Over-The-Counter Use (21 CFR 801 Subpart C)

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510(k) SUMMARY

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92. The assigned 510(k) number is K172514.

807.92 (a)(1): Name:	Sandstone Diagnostics, Inc.
Address:	6111 Southfront Road, Suite JLivermore, CA 94551
Phone:	925-315-7246
FAX:	925-215-2269
Contact:	Ulrich Schaff, PhD

807.92 (a)(2): Device name- trade name and common name, and classification

Trade name: Trak® Male Fertility Testing System

Common Name: Semen Analysis Test

Classification: 21 CFR § 864.5220

807.92 (a)(3): Identification of the legally marketed predicate devices

Trak® Male Fertility Testing System, Sandstone Diagnostics, Inc., Livermore, CA, K153683

807.92 (a)(4): Device Description

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807.92 (a)(5): Intended Use

Comparison	Subject DeviceTrak® Male Fertility TestingSystem(revised)	Predicate DeviceTrak® Male Fertility TestingSystem(K153683)
Intended Use	The Trak® Male Fertility TestingSystem is intended for semi-quantitative assessment of spermconcentration at 15 million sperm permilliliter (M/mL) or below, between 15and 55 M/mL, and above 55 M/mL. Italso provides a qualitative assessmentof semen volume.Sperm concentration and semen volumeare only two factors that could impact aman's fertility status and time topregnancy. For complete assessment ofmale reproductive health, the usershould consult a physician. For in vitro,over the counter home use.	The Trak® Male Fertility TestingSystem is intended for semi-quantitative assessment of spermconcentration at 15 million sperm permilliliter (M/mL) or below, between15 and 55 M/mL, and above 55M/mL.Sperm concentration is only one factorthat could impact a man's fertility statusand time to pregnancy. For completeassessment of male reproductive health,the user should consult a physician. Forin vitro, over the counter home use.
Class	Class II	Same
Regulation Number	21 CFR 864.5220	Same
Product Code	POV	Same
Branch	Hematology (81)	Same

807.92 (a)(6): Technological Similarities and Differences to the Predicate

The following chart describes similarities and differences between the revised Trak system and

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Comparison	Subject DeviceTrak® Male Fertility TestingSystem(revised)	Predicate DeviceTrak® Male Fertility TestingSystem(K153683)
Class	Class II	Same
Test Type	Semi-Quantitative and Qualitative	Semi-Quantitative
Test Locale	Home use	Same
Sample Type	Human semen	Same
Test Reporting	Visual readout of cell column height andVisual readout of fluid height	Visual readout of cell column height
Test Principle	Centrifuged packed cell volume andgraduated chamber fluid volume	Centrifuged packed cell volume
Concentration PrimaryCut-off	15 M/mL (lower reference limit, WHOsemen analysis guidelines 5th edition,2010)	Same
ConcentrationSecondary Cut-off	55 M/mL (indication of reduced time topregnancy based on Slama et al 2002study)	Same
Volume Cut-off	1.5 mL (lower reference limit, WHOsemen analysis guidelines 5th edition,2010)	None
Test Control Method	External Quality Control test solution	Same

807.92 (b)(1): Brief Description of Nonclinical Data

Precision of Volume Cup

The objective of this study was to assess the precision of the Volume Cup. Three lots of Volume Cups were qualitatively evaluated by three operators over five days on 5 artificial semen samples with different volumes and were compared with the reference volume. Each combination of day and operator/lot were tested in 5 replicates to obtain 75 total replicates per semen volume.

Summary results

The following includes grand averages for each condition, sum for each category and percent correct calls with respect to the reference method.

ID #	ReferenceVolume (mL)	# Results ≤ 1.5mL	# Results > 1.5mL	% Correct	Quant Volume resultgrand average ± SD (mL)
1	1.2 mL	75	0	100	1.32 ± 0.12
2	1.3 mL	74	1	98.7	1.43 ± 0.09
3	1.5 mL	17	58	n/a*	1.61 ± 0.10
4	1.7 mL	1	74	98.7	1.86 ± 0.16
5	1.8 mL	0	75	100	1.93 ± 0.10

no performance goal at the threshold; data tabulated for information, only

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ID#	N	Mean	Residual		Between Day		BetweenOperator‡		Operator*Day†		Total SDand %CV
			SD	CV	SD	CV	SD	CV	SD	CV	SD	CV
1	75	1.32	0.08	6.1%	0.07	5.0%	0	0.0%	0.06	4.8%	0.12	9.2%
2	75	1.43	0.06	4.0%	0.02	1.6%	0.02	1.3%	0.07	4.7%	0.09	6.5%
3	75	1.61	0.09	5.5%	0.00	0.0%	0.00	0.0%	0.05	2.8%	0.10	6.2%
4	75	1.86	0.09	5.0%	0.03	1.4%	0.00	0.3%	0.00	0.0%	0.10	5.2%
5	75	1.93	0.10	5.1%	0.02	1.2%	0.01	0.6%	0.00	0.0%	0.10	5.3%

The following includes SD (mL) and %CV between Day, between Operator/Lot, and total for each concentration.

#Operator factor is convolved with Lot: each operator used a unique lot.

*This is an interaction effect, it was found to be significant for some volumes tested.

The Volume Cup meets expected concordance for precision within operators/lots, days, and runs.

Functional Equivalence to Previous Cup

A series of studies were performed to prove that the Volume Cup functions equivalently to the previous Collection Cup in (1) promoting semen liquefaction, (2) semen homogenization; and (3) generating the equivalent Trak sperm concentration result.

Semen Liquefaction

The objective of this study was to determine the effectiveness of new Volume Cup in promoting semen liquefaction. A total of 20 semen sample aliquots from three semen samples were tested for liquefaction by measuring the volume of semen dispensed by the transfer devices included with the Trak System (250 µL exact volume pipettes) after incubation according to directions.

Summary results

A total of three semen samples were used in this study, with no more than 10 repeat measurements from a single sample. All samples were confirmed as liquefied and non-viscous at 30 minutes. The total average for these volume measures was 253.05 µL, with a 95% CI of 249.60 - 256.00 µL, meeting the acceptance criteria.

The data supports that the Volume Cups are effective at promoting semen liquefaction.

Trak Sperm Concentration Category Result Equivalence Study

The objective of this study was to determine whether samples incubated in the new Volume Cup give equivalent Trak category results to samples incubated in the previous Collection Cup. Two sperm concentrations in the vicinity of the WHO threshold cutoff (15 M/mL) were tested in 20 replicates for each cup type on Trak Props, and results were categorized as ≤ 15 M/mL (Low), 15 - 55 M/mL (Moderate), and > 55 M/mL (Optimal).

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Summary results

The following includes summary of results in this study. All conditions were categorized correctly with respect to the reference method at least 90% of the time. Both semen pools were first formulated as a single pool, then divided evenly over the two cup types, and then CASA confirmed for both cups types just before Trak assay initiation.

Nominal Pool Condition	Measured CASA results				AverageConcentrationof sample	TrakResults ≤15 M/mL	TrakResults 15– 55M/mL
10 M/mL, control	10.2	11.0	11.9	12.3	11.4	20	0
10 M/mL, volume cup	10.8	11.4	11.4	13.0	11.7	20	0
20 M/mL, control	21.0	17.9	21.8	21.9	20.7	0	20
20 M/mL, volume cup	20.0	19.1	19.5	20.2	19.7	0	20

Trak results for both the new Volume Cup and the previous Collection cup were correctly categorized with respect to the reference method 100% of the time, exceeding the study acceptance criteria.

Semen Homogenization study

The objective of this study was to determine whether sperm concentration is evenly distributed within the new Volume Cup vs the previous Collection Cup when agitated. Semen samples were formulated to two sperm concentrations differing by more than 50%. Twenty (20) aliquots were taken from the top and bottom of each cup for each pool, and its sperm concentration was accessed.

The two cups performed equivalently.

Summary results

The following includes average results by unique condition, cup type, and grand mean for pools. Sample deviations (SD) are also shown.

Pool ID	Cup Type	Location	n	Mean ± SD(M/mL)	Cup typeMean ± SD(M/mL)	GrandMean ± SD(M/mL)
A	Collection Cup(Previous)	Top	20	17.1 ± 0.7	17.1 ± 0.7	17.3 ± 0.8
		Bottom	20	17.2 ± 0.7
	Volume Cup(New)	Top	19	17.5 ± 0.7	17.5 ± 0.8
		Bottom	20	17.5 ± 0.9
B	Collection Cup(Previous)	Top	20	36.4 ± 2.2	35.3 ± 2.5	36.1 ± 2.5
		Bottom	20	34.3 ± 2.5
	Volume Cup(New)	Top	20	36.7 ± 2.6	36.9 ± 2.2
		Bottom	20	37.1 ± 1.8

807.92 (b)(2): Brief Description of Clinical Data

Two studies were performed to assess Lay Subject validation for the 1.5 mL reference marking on the new Volume Cup. Users were asked to determine semen volume with respect to 1.5 mL reference mark, where a volume less than 1.5 mL is considered a positive result for hypospermia.

Stage 1 Study: Interpretation of Photographs

The objective of the study was to demonstrate the accuracy of the new Volume Cup as interpreted by the intended users. A total of 232 semen sample photographs were interpreted as ≤ 1.5 mL or

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1.5 mL by Lay Subjects as well as trained technicians (blinded to the result), and were confirmed with the result obtained by the reference method.

The descriptive demographic statistics for the Lay Subjects (n = 52) were as follows. Subjects were 28.0 years on average (range 18.0 - 68.0), with a high prevalence of male gender (57.7%). Caucasians (44.2%) with some college education (40.4%). We also performed lay user interpretation questionnaire, and a majority (90.4%) of Lay Subjects gave answers indicating an understanding of the instructions according to the intended interpretation.

Summary results Primary Analysis - Sensitivity and specificity for Lay Subject interpretation

The following includes 2 x 2 contingency table, with study results, for performance estimates of Lay Subjects versus reference method.

Image /page/8/Figure/4 description: This image shows a 2x2 table that compares the lay subject result to a reference result. The table shows the number of results for each category. 98 results were less than or equal to 1.5 mL for both the lay subject and reference results. 125 results were greater than 1.5 mL for both the lay subject and reference results.

Reference result, n = 232

The following includes performance parameters for Lay Subject interpretation versus reference method.

Sensitivity, %(95% CI)	Specificity, %(95% CI)
97.0%(91.6 – 99.0%)	95.4 %(90.4 – 97.9%)

Additionally, the overall percent agreement (OPA or "accuracy") was found to be 96.1% (92.8 -97.9%). For the analysis set, 9 (3.9%) of interpreted results were discordant versus the reference method, with 6 (2.6%) indicating false positive results and 3 (1.3%) indicating false negative results. Of the Lay Subject vs. reference discrepant results, 9 (100%) were within 0.5 mL of the 1.5 mL threshold with reference results, often reading above 1.5 mL.

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Trained Technician volume results versus reference results

The following includes 2 x 2 contingency table, with study results, for performance estimates of Trained Technicians versus reference method.

Image /page/9/Figure/2 description: This image shows a 2x2 confusion matrix comparing technician results to reference results for a sample size of 232. The matrix compares results for values less than or equal to 1.5 mL and greater than 1.5 mL. The top left cell shows 100, the top right cell shows 4, the bottom left cell shows 4, and the bottom right cell shows 124.

The following includes performance parameters for Trained Technician interpretation versus reference method

Sensitivity, %	Specificity, %
(95% CI)	(95% CI)
96.2%	96.9%
(90.5 - 98.5%)	(92.2-98.8%)

Additionally, the OPA was found to be 96.6% (93.3 - 98.2%). For the analysis set, 8 (3.4%) of interpreted results were discordant versus the reference method, with 4 (1.3%) indicating false negatives and 4 (1.3%) indicating false positive results. Of the Technician vs. reference discrepant results, 8 (100%) were within 0.5 mL of the 1.5 mL threshold.

Trained Technician results versus Lay Subject results

The following includes trained Technician vs Lay Subject interpretation contingency table.

		≤ 1.5 mL	> 1.5 mL
Lay Subject result	≤1.5 mL	100	1
	>1.5 mL	4	127

Trained Technician result, n = 232

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The following includes descriptive statistics showing positive percent agreement (PPA), negative percent agreement (NPA) and overall agreement between Lay and Technician interpretation.

OPA, %(95% CI)	PPA, %(95% CI)	NPA, %(95% CI)
97.8%(95.1 – 99.1%)	96.2%(90.5 – 98.5%)	99.2%(95.7 – 99.9%)

Trained technician tended to agree with the Lay Subject more than 95% of the time, with the lower bound of all comparison statistics above 90%. In this analysis set, Technician and Lay Subject disagreed on 5 (2.2%) of the samples.

Stage 2 Study: Interpretation of Simulated Sample in the Volume Cup

The objective of the second study was to assess interpretation and ease of use of the physical Volume Cup filled with known volumes of artificial semen as interpreted by the intended users.

A total of 127 semen sample photographs were interpreted as ≤ 1.5 mL, > 1.5 mL, or Invalid by 32 Lav Subjects. Each Lay Subject interpreted 4 Cups filled with 1 mL, 1.2 mL, or 2 mL of artificial semen in random order.

The descriptive demographic statistics for the Lay Subjects (n = 32) were as follows. Subjects were 35.1 years on average (range 25- 59), with a high prevalence of Caucasians (53.1%) with post-graduate education (53.1%).

Summary results Primary Analysis – Sensitivity and specificity for Lay Subject interpretation

The following includes 2 x 2 contingency table for performance estimates versus reference method with Stage 2 results.

Image /page/10/Figure/9 description: This image shows a 2x2 confusion matrix comparing the results of a reference test and a lay subject test. The reference test has 127 samples. The matrix shows that when the reference result is less than or equal to 1.5 mL, the lay subject result is less than or equal to 1.5 mL 60 times, and greater than 1.5 mL 3 times. When the reference result is greater than 1.5 mL, the lay subject result is less than or equal to 1.5 mL 2 times, and greater than 1.5 mL 62 times.

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The following includes performance parameters for Lay Subject interpretation versus reference method.

Sensitivity, %(95% CI)	Specificity, %(95% CI)
95.2%(86.9-98.4%)	96.9%(89.3-99.1%)

These results suggest that in the hands of Lay Subjects, the Volume Cup with appropriate instructions provides adequate resolution of semen volume in the vicinity of the WHO threshold for hypospermia.

Lay Subject Questionnaire results

Lav Subjects, after completing a volume cup reader study, also completed a Tester Questionnaire with 11 multiple choice questions. Five of the questions were designed to capture the subject's perceptions of ease of use of the Trak device, and the remaining six questions were to gauge interpretation and understandability of the instructions. While slightly more than a quarter of the respondents assigned "somewhat difficult" or "difficult" to the task of finding the liquid level, more than 95% of the responses for interpreting cups were assigned correctly with respect to the reference method. Additionally, a majority (90.6%) of testers gave answers indicating an understanding of the instructions according to the intended interpretation.

CONCLUSIONS

Sandstone Diagnostics. Inc. has performed two cross-sectional studies of a suitable sample sizes to investigate and determine the substantial equivalence of their device to a recognized reference method of semen volume measurement via a calibrated scale. The results of the prospectively stated primary analyses indicate the lower bound of the 95% confidence interval for sensitivity and specificity meeting the pre-specified acceptance criteria. Specifically, Stage 1 resulted in an observed sensitivity of 97.0% (95% CI: 91.6 - 99.0%) and specificity of 95.4% (95% CI: 90.4 -97.9%) with the lower bound of the 95% confidence intervals meeting the acceptance criteria of > 80% for both sensitivity and specificity. An overall percent agreement ("accuracy") between Lay Subject and Reference method was found to be 96.1% (92.8 - 97.9%). Stage 2 resulted in an observed sensitivity of 95.2% (95% CI: 86.9-98.4%) and specificity of 96.9% (95% CI: 89.3-99.1%), also meeting acceptance criteria. These outcomes provide evidence supporting the accuracy of the Trak volume test when used by lay testers representing the population of intended use.

Further, Trak volume results generated by subjects generally agreed with results from the same specimens tested by trained users, indicating the quality of the instructions for use. Subjects from the Stage 2 study presented with filled cups generally felt the volume cup would be easy to use in terms of procedure and interpretation of results with regard to the clinical threshold of 1.5 mL. In summary, the study demonstrated substantial equivalence of the Trak volume test in comparison to the reference method in the hands of the intended use population.

807.92 (b)(3): Brief Description of Clinical Data

The conclusions drawn from the analytical and clinical data demonstrate that the device is safe and effective for its intended use.

Regulation Number and Section

§ 864.5220 Automated differential cell counter.

(a)
Identification. An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.(b)
Classification. Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”