Affirm One-Step home pregnancy test is a rapid one-step visual test for the qualitative detection of human chorionic gonadotropin in human urine to aid in the diagnosis of pregnancy. This test is intended for over-the-counter home use.

Device Description

Affirm detects the presence of hCG in urine by using a combination of polyclonal and monoclonal antibodies on the reagent pad and the test strip. The assay begins functioning with the addition of urine onto the absorbent wick. Through capillary action the urine is pulled along the membrane to the reagent pad where the hCG reacts with the conjugate. Positive results are determined by one color line in the test window and one color line in the control window. The absence of hCG produces only one color line in the control window.

AI/ML Overview

Here's an analysis of the provided text regarding the Affirm One-Step home pregnancy test, structured according to your request:

In this case, the acceptance criteria are largely implied rather than explicitly stated with numerical targets for specificity, sensitivity, and accuracy. The study aims to demonstrate that the device performs comparably to a predicate device and effectively detects hCG at a specified concentration.

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria Category	Implied Acceptance Criteria (from text)	Reported Device Performance
Specificity (Cross-reactivity)	No cross-reactivity with LH, FSH, and TSH at specified concentrations.	"Affirm did not cross-react with these substances [LH, FSH, TSH] at these levels [300mIU/ml LH, and 1000mIU/ml FSH and TSH]." (Only showed positive when 25mIU/ml hCG was also present).
Sensitivity (Analytical)	Detect hCG at a clinically relevant concentration (e.g., 25mIU/ml) within the specified timeframe.	"The 20 samples tested at the 25mlU/ml concentration all generated a positive reading well within the 20 minutes, therefore our claim is a 25mlU/ml sensitivity with the Affirm One-Step home pregnancy test. Even though the test is sensitive enough to read concentrations lower than 25mIU/ml this does not occur regularly for us to claim a lower sensitivity for the test." (Also noted: 5/20 samples positive at 10mIU/ml after 15 mins).
Accuracy (Analytical)	Consistent and correct detection of hCG at varying concentrations.	At 25, 50, and 100 mIU/ml hCG, all 20 samples tested positive (100% accuracy at these concentrations). At 0 mIU/ml hCG, all 20 samples tested negative (100% accuracy). At 10 mIU/ml hCG, 5 out of 20 samples tested positive (25% accuracy for positive-detection at this concentration).
Interfering Substances	No interference from common substances at specified concentrations.	"NONE" reported for Acetaminophen (20 mg/dI), Acetylsalicylic Acid (20 mg/dI), Ascorbic Acid (20 mg/dI), Atropine (20 mg/dI), Caffeine (20 mg/dI), Gentisic Acid (20 mg/dI), Glucose (2 mg/dI), Hemoglobin (200 mg/dI) in both hCG negative and 25 mIU/ml hCG spiked samples.
Predicate Device Correlation	High concordance with a legally marketed predicate device (SAS™ Pregnancy Strip).	"Both the Affirm One-Step home pregnancy test and the SAS™ Pregnancy Strip identified 54 true positives and 46 true negatives generating a 100% sensitivity for the Affirm One-Step home pregnancy test." (Implies 100% agreement on true positives and true negatives, and thus 100% specificity for the "true negatives" as well, though not explicitly stated as such).

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

Specificity Test: The sample size is not explicitly stated as unique samples for LH, FSH, and TSH, but 25 mIU/ml hCG was tested simultaneously. It implies that at least one sample for each substance was tested.
Sensitivity and Accuracy (Analytical): 20 negative urine samples were used, which were then "spiked with hCG at varying levels." This means 20 samples were tested at each concentration level: 10mIU/ml, 25mIU/ml, 50mIU/ml, 100mIU/ml, and 0mIU/ml.
Interfering Substances: For each of the 8 interfering substances, samples were tested both with and without 25 mIU/ml hCG. The specific number of samples for each substance is not given, but it implies at least one sample for each condition.
Predicate Device Result Correlation: 100 specimens.
Data Provenance:
- Analytical studies (Specificity, Sensitivity, Accuracy, Interfering Substances): The text does not explicitly state the country of origin but references "spiked" samples, indicating these were laboratory-controlled rather than collected from patients directly.
- Predicate Device Result Correlation:
  - Country of Origin: Not explicitly stated, but "clinics around town" and "Planned Parenthood in either Southeast Portland or Beaverton" (Oregon, USA) suggest the data is from the United States.
  - Retrospective or Prospective: Prospective. The women were "solicited by a flyer" and asked to participate.

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

Analytical Studies (Specificity, Sensitivity, Accuracy, Interfering Substances): For spiked samples (known concentrations of hCG, LH, FSH, TSH, and interfering substances), the "ground truth" is established by the laboratory's precise control over the spiked concentrations. No human experts are typically used to establish ground truth in this context; it's based on biochemical assays and measurements.
Predicate Device Result Correlation: The ground truth for the 100 specimens (54 true positives and 46 true negatives) is implied to be established by the predicate device itself (SAS™ Pregnancy Strip), which is used as the reference test. No explicit number of experts or their qualifications are mentioned for establishing the "true positive" or "true negative" status of these clinical samples beyond the performance of the predicate device.

4. Adjudication Method for the Test Set

None explicitly stated. For the analytical studies, the results are directly read from the device and compared to the known spiked concentrations. For the predicate device correlation, it's a direct comparison of the Affirm device's result to the SAS™ Pregnancy Strip's result for each specimen. There's no mention of multiple readers or an adjudication process for discrepancies.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No. This type of study (MRMC) is not mentioned or described. The study focuses on the device's standalone performance and its comparison to a predicate device, not on how human readers' performance improves with or without AI assistance. This device is a home-use, over-the-counter diagnostic test, not a system designed to assist healthcare professionals in interpretations.

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

Yes. The entire performance evaluation for the Affirm One-Step home pregnancy test is a standalone assessment. It's a consumer-use device where the user reads the visual result directly from the test strip without any "human-in-the-loop" decision support from an algorithm. The reported performance characteristics (specificity, sensitivity, accuracy, interference, and correlation study) all reflect the device's inherent capability to detect hCG.

7. The Type of Ground Truth Used

Analytical Studies (Specificity, Sensitivity, Accuracy, Interfering Substances): Laboratory-controlled spiked concentrations of hCG and other substances. This represents a highly controlled, synthetic form of ground truth.
Predicate Device Result Correlation: The results from the SAS™ Pregnancy Strip were used as the reference standard (ground truth) for the 100 clinical specimens.

8. The Sample Size for the Training Set

This information is not provided in the summary. Pregnancy tests like this are typically developed through biochemical and immunoassay research and optimization, rather than machine learning models that require labeled training sets in the computational sense. The "training" would involve optimizing antibody concentrations, membrane types, and reaction conditions.

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

This information is not provided as there isn't a conventional "training set" in the machine learning sense for this type of device. The development process would have involved establishing optimal performance characteristics through experimental design, using known concentrations of analytes (hCG, interfering substances) in the laboratory. The ground truth for this optimization would be based on the accurate measurement of these analytes in controlled laboratory settings.

Summary

{0}------------------------------------------------

510(k) Summary

K962888

Athena Medical Corporation 10180 SW Nimbus Ave. Suite J-5 Portland, OR 97223

SEP 23 1996

Krista Lopardo Phone: 503/968-8800 ext. 19 Fax: 503/639-3674

Proprietary Name: Affirm One-Step home pregnancy test

Classification Name: Human chorionic gonadtropin test systems

OneStep Be Sure® Plus Midstream Pregnancy Home Test

SASTM Pregnancy Strip

July 19, 1996

Submitted by:

Contact:

Product Name:

Intended Use:

Description of Device:

Predicate device for substantial equivalence comparison:

Predicate device used as reference test for clinical data:

Date Prepared:

{1}------------------------------------------------

Performance characteristics:

Specificity:

Affirm One-Step home pregnancy test was evaluated for specificity against LH, FSH and TSH. At concentrations of 300mIUml LH, and 1000mIU/ml FSH and TSH. Affirm did not cross-react with these substances at these levels. Only when Affirm was compared to these three substances and a 25mlU/ml concentration of hCG simultaneously did the tests respond and show a positive reading for the presence of hCG.

Sensitivity and Accuracy:

The sensitivity and accuracy of the Affirm One-Step home pregnancy test was determined using 20 negative urine samples spiked with hCG at varying levels. The following results are described in the table on the following page.

ConcentrationSpiked at:	Results: Positive	Results: Negative
10mIU/ml	5	15
25mIU/ml	20	0
50mIU/ml	20	0
100mIU/ml	20	0
0mIU/ml	0	20

Sensitivity of Affirm One-Step home pregnancy test

Out of the 20 samples that were tested at the 10mIUml concentration, 5 of them did generate a positive reading after about 15 minutes from the point of saturation. The 20 samples tested at the 25mlU/ml concentration all generated a positive reading well within the 20 minutes, therefore our claim is a 25mlUml sensitivity with the Affirm One-Step home pregnancy test. Even though the test is sensitive enough to read concentrations lower than 25mIU/ml this does not occur regularly for us to claim a lower sensitivity for the test.

{2}------------------------------------------------

Interfering Substances:

The following potentially interfering substances were added to hCG negative and 25 mIU/ml hCG spiked urine samples. Interfering test samples were compared directly to the control result. The following results are described in the table:

Substance:	Concentration:	Interference:
Acetaminophen	20 mg/dI	NONE
Acetylsalicylic Acid	20 mg/dI	NONE
Ascorbic Acid	20 mg/dI	NONE
Atropine	20 mg/dI	NONE
Caffeine	20 mg/dI	NONE
Gentisic Acid	20 mg/dI	NONE
Glucose	2 mg/dI	NONE
Hemoglobin	200 mg/dI	NONE

Interference of the Affirm One-Step home pregnancy test

Predicate Device Result Correlation:

One hundred specimens were evaluated by the urine stream method and the dip method. The women participating in the study were solicited by a flyer appearing in clinics around town. and asked to participate at one of the following locations: Athena Medical Corporation, Planned Parenthood in either Southeast Portland or Beaverton. Women who participated in the urine stream method answered a questionnaire about the product. Both the Affirm One-Step home pregnancy test and the SAS™ Pregnancy Strip identified 54 true positives and 46 true negatives generating a 100% sensitivity for the Affirm One-Step home pregnancy test.

{3}------------------------------------------------

Substantial Equivalence:

Comparison Product:	Be Sure® Plus
Manufactured by:	Syntron Bioresearch Inc.
	Carlsbad, CA 92008

Similarities to Be Sure® Plus:

Items to be compared	Affirm One-Step homepregnancy test	Be Sure® Plus
· Detection method:	hCG in urine specimens reactswith the colored-conjugate on thepad producing a solid color (red)line in the test region. Mouseconjugate binds to goat anti-mouse antibody in the controlregion on the strip.	hCG in urine specimens reactswith the colored-conjugate on thepad producing a solid color (red)line in the test region. Mouseconjugate binds to goat anti-mouse antibody in the controlregion on the strip.
· Usage:	Anytime of the day.	Anytime of the day.
· Pregnancy determination:	As early as the first day of awomen's missed period.	As early as the first day of awomen's missed period.
· Antibodies:	Polyclonal goat anti-alphaantibody hCG is on the test strip,monoclonal anti-beta antibodyhCG is on the conjugate pad, andpolyclonal goat anti-mouseantibody is on the control line.	Polyclonal goat anti-alphaantibody hCG is on the test strip,monoclonal anti-beta antibodyhCG is on the conjugate pad, andpolyclonal goat anti-mouseantibody is on the control line.
· Results:	Positive = color line in testwindow and control window.Negative = color line in controlwindow only.	Positive = color line in testwindow and control window.Negative = color line in controlwindow only.
· Format:	Lateral Flow assay	Lateral Flow assay
· Sensitivity:	Detects level of hCG as low as25mIU/ml.	Detects level of hCG as low as25mIU/ml.
· Device design:	Slender, pen-like shape,removable cap, absorbent tippartially enclosed, two windowresult view.	Slender, pen-like shape,removable cap, absorbent tippartially enclosed, two windowresult view.
· Visual detection:	A solid color line appears incontrol and test window in thepresence of hCG.A solid color line appears in thecontrol window only in theabsence of hCG.	A solid color line appears incontrol and test window in thepresence of hCG.A solid color line appears in thecontrol window only in theabsence of hCG.
Items to be compared	Affirm One-Step homepregnancy test	Be Sure® Plus
• Device engineering:	Both the result windows and the"tear drops" exposing theabsorbent wick appear on thesame side of the device. Areacovering wick is smallerproducing a smaller cap. Resultwindow includes a moistureresistant clear barrier.	Both the result windows and the2 square windows exposing theabsorbent wick are on oppositesides of the device. Area coveringthe absorbent wick is largerproducing a larger cap.
• Developing time:	Less than 4 minutes for theresults to appear.	Less than 5 minutes for theresults to appear.
• Absorbent wick:	Partially enclosed except for 2"tear drops" carved out of theplastic housing.	Partially enclosed except for 2squares cut out of the plastichousing.
• Results windows:	Covered by a clear plastic shieldwhich acts as splash guard toprotect the results.	Fully exposed result windowwith no plastic covering.
• Test window/Control window:	Test window shape is: "+".control window shape is: "o".	Test window is a rectangle whilethe control window is a square.
• Color of holder:	Ivory	Blue/White

{4}------------------------------------------------

Differences between Affirm and Be Sure® Plus:

The differences between the Affirm One-Step home pregnancy test and Be Sure® Plus are insignificant and do not effect the safety and effectiveness of the device in any significant way.

Regulation Number and Section

§ 862.1155 Human chorionic gonadotropin (HCG) test system.

(a)
Human chorionic gonadotropin (HCG) test system intended for the early detection of pregnancy —(1)Identification. A human chorionic gonadotropin (HCG) test system is a device intended for the early detection of pregnancy is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class II.(b)
Human chorionic gonadotropin (HCG) test system intended for any uses other than early detection of pregnancy —(1)Identification. A human chorionic goadotropin (HCG) test system is a device intended for any uses other than early detection of pregnancy (such as an aid in the diagnosis, prognosis, and management of treatment of persons with certain tumors or carcinomas) is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class III.(3)
Date PMA or notice of completion of a PDP is required. As of the enactment date of the amendments, May 28, 1976, an approval under section 515 of the act is required before the device described in paragraph (b)(1) may be commercially distributed. See § 862.3.