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The Strep A Rapid Test Strip (Throat Swab) is a rapid chromatographic immunoassy for the qualitative detection of Streptococcus pyogenes (Group A B-hemolytic Streptococcus, Strep A) antigen from throat swab specimens of symptomatic patients to aid in the diagnosis of Group A Streptococcus bacterial infection.

All negative test results should be confirmed by bacterial culture because negative results do not prection with Group A Streptococcus and should not be used as the sole basis for treatment.

Healgen Strep A Rapid Test Strip (Throat Swab) is a qualitative, lateral flow immunoassay for the detection of Strep A antigen directly from a throat swab sample.

In this test, antibody specific to Strep A carbohydrate antigen is coated on the test line region of the test. During testing, the extracted throat swab specimen reacts with an antibody to Strep A that is coated onto particles. The mixture migrates up the membrane to react with the antibody to Strep A on the membrane and generate a color line in the test line region. The presence of this color line in the test line region indicates a positive result, while its absence indicates a negative result. To serve as a procedural control, a colored line will always appear in the control line region, indicating that proper volume of specimen has been added and membrane wicking has occurred.

Here's a breakdown of the acceptance criteria and study details for the Healgen Strep A Rapid Test Strip (Throat Swab):

1. Table of Acceptance Criteria and Reported Device Performance

• True negative sample: 0% (0/180)
• Moderate positive sample (1.8x10^4 CFU/mL): 100% (180/180)
• LoD sample (7.2x10^3 CFU/mL): 95.6% (172/180)
• Low negative sample (3.6x10^3 CFU/mL): 44.4% (80/180)
  (Concluded: No significant differences between users, sites, lots, and days; results are reproducible with good precision.) |
  | Limit of Detection (LoD) | The LoD should be clearly established for both clinical matrix and saline solution. | LoD in clinical matrix: 7.2x10^3 CFU/mL (equivalent to 360 bacteria on the swab) based on 95.2% detection (20/21) at 7.2x10^4 CFU/mL.
  LoD in saline solution: 7.2x10^3 CFU/mL (equivalent to 360 bacteria on the swab) based on 95.2% detection (20/21) at 7.2x10^3 CFU/mL. |
  | Interference | No false positive or false negative results with common interfering substances (blood, mucus, saliva, medications). | No false positive or false negative results observed with various interfering substances (blood, mucin, OTC mouthwashes, lozenges, throat sprays, cough syrups, active ingredients such as acetaminophen, ibuprofen, etc.) at tested concentrations (e.g., 20% vol/vol for liquids, 5mg/mL for solids). |
  | Analytical Specificity | No cross-reactivity with other common respiratory tract organisms (bacteria and viruses). | No cross-reactivity found for a comprehensive list of organisms (e.g., Arcanobacterium haemolyticum, Bordetella pertussis, Candida albicans, Enterococcus faecalis, Escherichia coli, various Streptococcus species, Adenovirus, Cytomegalovirus, HSV, etc.) at tested concentrations. |
  | Clinical Performance | | |
  | Clinical Sensitivity | Performance comparable to the legally marketed predicate device (Predicate: 95% CI (88-98%)). | Overall Clinical Sensitivity: 97.1% (200/206) with 95% CI (93.7-98.8%)
• Age 0-5: 97.4% (74/76)
• Age 5-21: 96.7% (119/123)
• Age 21+: 100% (7/7)
  (No statistical differences between age groups.) |
  | Clinical Specificity | Performance comparable to the legally marketed predicate device (Predicate: 98% CI (96-99%)). | Overall Clinical Specificity: 99.4% (161/162) with 95% CI (96.2-100.0%)
• Age 0-5: 98.1% (52/53)
• Age 5-21: 100% (88/88)
• Age 21+: 100% (21/21)
  (No statistical differences between age groups.) |
  | Consistency | Performance across different age groups should be consistent. | No statistical differences in performance between age groups. |

2. Sample size used for the test set and the data provenance

• Test Set Sample Size:
  • Clinical Study: 368 subjects (206 culture-positive, 162 culture-negative).
  • Analytical Precision: 180 determinations per sample type (60 determinations per site across 3 sites).
  • Analytical LoD: 21 results per dilution (7 operators x 3 lots).
  • Analytical Interference: Multiple tests across 3 lots for each interfering substance, for both positive and negative specimens.
  • Analytical Specificity (Cross-reactivity): Multiple tests across 3 lots for each organism by 3 professional users.
• Data Provenance:
  • The document does not explicitly state the country of origin for the clinical data.
  • The clinical study appears to be prospective/concurrent as it describes testing "subjects...exhibiting symptoms of pharyngitis by both the Healgen Strep A Rapid Test Strip (Throat Swab) and the culture studies." This implies collection of samples and testing using both methods at the time of study.
  • The analytical studies (precision, LoD, interference, specificity) were laboratory-based, performed internally or by designated personnel.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

• Clinical Study Ground Truth: The ground truth for the clinical study was established by bacterial culture. The document implies that the culture results were considered the reference standard. It does not explicitly state the number of experts or their qualifications involved in performing or interpreting these cultures. However, bacterial culture is a standard clinical laboratory method typically performed by trained medical technologists or microbiologists.
• Analytical Studies:
  • Precision/Reproducibility: 6 professional operators (2 at each of 3 sites) participated. Their specific qualifications are not detailed beyond "professional operators."
  • LoD: 7 operators performed the testing. Their specific qualifications are not detailed beyond "operators."
  • Interference: 3 laboratory assistants with relevant experience performed the test.
  • Analytical Specificity: 3 professional users performed the test.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set

• The document does not describe an adjudication method (like 2+1 or 3+1) for establishing the ground truth in the clinical study. The reference standard (bacterial culture) appears to have been used directly.

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 Multi-Reader Multi-Case (MRMC) comparative effectiveness study was done in the context of AI assistance. This device is a manual rapid diagnostic test strip, not an AI-assisted diagnostic tool. Therefore, the concept of human readers improving with AI assistance is not applicable here. The "operators" or "users" in the analytical studies are performing the manual test according to instructions.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

• This question is not applicable as the device is a manual rapid test strip, not an algorithm or AI-driven system. It does not operate without human interaction.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

• The ground truth for the clinical study was bacterial culture, which is considered the gold standard for diagnosing Group A Streptococcus bacterial infection.
• For the analytical studies (LoD, interference, specificity), the ground truth was based on known concentrations of target analytes (S. pyogenes) or known presence/absence of interfering/cross-reacting organisms.

8. The sample size for the training set

• The document does not mention a training set in the context of machine learning or AI. This is a traditional rapid diagnostic test, not a learning algorithm. The "training" of the device refers to its manufacturing and validation process, not data-driven machine learning.

9. How the ground truth for the training set was established

• This question is not applicable as there is no mention or indication of a "training set" for an AI or machine learning model in this submission.

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The Sofia Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by either bacterial culture or an FDA-cleared molecular assay because negative results do not prection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

The Sofia Strep A+ FIA may be used with Sofia or Sofia 2.

The Sofia Strep A+ FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's Swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Test Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia or Sofia 2. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia or Sofia 2.

Depending upon the user's choice, the Test Cassette is either placed inside of Sofia or Sofia 2 for automatically timed development (WALK AWAY Mode) or placed on the counter or bench top for a manually timed development and then placed into Sofia 2 to be scanned (READ NOW Mode).

Sofia or Sofia 2 will scan the test strip and measure the fluorescent signal by processing the results using method-specific algorithms. Test results will be displayed (Positive, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected.

Sofia 2 is a microprocessor-controlled device about the size of a desk top telephone and weighs less than 3 pounds. Sofia 2 uses a fluorescent tag that is illuminated by an Ultraviolet (UV) light source to generate specific results.

The Sofiea Strep A+ FIA is a device intended to detect Group A Streptococcal antigens from throat swabs of patients with signs and symptoms of pharyngitis. All negative test results must be confirmed by either bacterial culture or an FDA-cleared molecular assay.

As this is a 510(k) submission, the device does not have explicit acceptance criteria mentioned, but rather demonstrates substantial equivalence to a predicate device. The performance data section of the document describes several studies undertaken to document the performance characteristics of the Sofia 2 and the Sofia Strep A+ assay, as well as to compare performance between Sofia and Sofia 2.

Here's the information about the studies presented:

1. Table of Acceptance Criteria and Reported Device Performance:

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

The document does not explicitly state the sample sizes used for each test set in these studies, nor does it specify the country of origin of the data or whether the studies were retrospective or prospective. It refers to "a panel of clinical samples" for the Method Comparison study and "a panel of test samples" for the Reproducibility study.

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

This information is not provided in the document. The nature of the device (antigen detection) likely implies a microbiological gold standard (e.g., bacterial culture), rather than expert consensus on interpretation.

4. Adjudication Method for the Test Set:

This information is not provided in the document.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

A MRMC comparative effectiveness study involving human readers and AI assistance is not mentioned. The studies focus on the performance of the device itself and its equivalence to a predicate device.

6. Standalone Performance Study:

Yes, standalone performance studies were done. All the studies listed in the "Performance Data" section (LoD, Precision, Assay development time, Method Comparison, Reproducibility) assess the performance of the Sofia Strep A+ FIA on Sofia 2 (and its comparison to Sofia) as a standalone algorithm/device without explicit human-in-the-loop performance measurement.

7. Type of Ground Truth Used:

The document mentions that negative test results "should be confirmed by either bacterial culture or an FDA-cleared molecular assay." This implies that bacterial culture or an FDA-cleared molecular assay would serve as the ground truth for determining the presence or absence of Group A Streptococcal infection in the clinical sample studies.

8. Sample Size for the Training Set:

The document does not provide information about a specific training set or its sample size. This is common for this type of in vitro diagnostic device, where performance is evaluated against known concentrations or clinical samples with confirmed status, rather than training a machine learning model in the conventional sense.

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

As there is no mention of a traditional training set for a machine learning model, the method for establishing ground truth for a training set is not applicable or described in this document. The "ground truth" for the performance evaluation studies would be established using validated methods like bacterial culture or FDA-cleared molecular assays, as mentioned in the indications for use.

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The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen. The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia. Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode). Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.

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

Device: Sofia® Strep A+ FIA

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" numerically for sensitivity and specificity. However, based on the performance study results, the implied acceptance criteria would be the statistically significant ranges demonstrated by the device.

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

• Sample Size for Clinical Performance Study: 851 patients.
• Data Provenance: Retrospective, collected during 2014 from 7 distinct CLIA-waived sites in various geographical regions within the United States.

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

The document does not explicitly state the number of experts or their qualifications for interpreting the ground truth (bacterial culture and PCR). However, it mentions:

• "A central Reference Laboratory" conducted the bacterial culture and PCR. This implies qualified laboratory personnel.

4. Adjudication Method for the Test Set

The primary comparison was against standard bacterial culture. For discordant results between the Sofia Strep A+ FIA and culture, an "FDA-cleared molecular device" (RT-PCR assay) was used for resolution.

• Method: Initial comparison of Sofia Strep A+ FIA to bacterial culture.
• Discordant Resolution: For specimens where Sofia Strep A+ FIA and culture disagreed, an FDA-cleared molecular device (PCR) was used to resolve the discrepancy. This is a 2-step adjudication approach (initial culture, then PCR for discrepancies).

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with and without AI assistance was not done. This study is for a diagnostic device (FIA) that measures antigens, not an AI-powered image analysis system that would assist human readers in interpretation.

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

Yes, the clinical performance study directly evaluated the "rapid FIA test result" from the Sofia Strep A+ FIA against the ground truth. The device itself (Sofia Strep A+ FIA with the Sofia analyzer) provides the result (Positive, Negative, or Invalid) and automatically interprets the immunofluorescent signal using method-specific algorithms, thus representing a standalone performance evaluation.

7. The Type of Ground Truth Used

The ground truth for the clinical performance study consisted of:

• Bacterial Culture: Throat swabs were streaked on a sheep blood agar plate (SBA) and cultured for up to 48 hours.
• Molecular (PCR): An FDA-cleared Group A Streptococcus RT-PCR assay was used to resolve discordant results between the device and primary culture. This is a combination of culture and a highly sensitive molecular method.

8. The Sample Size for the Training Set

The document does not specify a separate "training set" sample size. This type of device (immunofluorescence assay) doesn't typically undergo a machine learning training phase in the same way an AI-powered diagnostic algorithm would. The development of its "method-specific algorithms" would be based on analytical studies (LoD, cross-reactivity, precision) to define positive/negative thresholds rather than a distinct training dataset of patient samples.

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

As noted above, a traditional "training set" with ground truth in the context of machine learning is not applicable here. The "method-specific algorithms" in the Sofia analyzer would have been developed and validated based on extensive analytical studies to establish appropriate thresholds for signal detection and interpretation. These analytical studies involved:

• Serial dilutions of known concentrations of Streptococcus pyogenes strains (for LoD).
• Testing against known non-Group A Streptococcus organisms and various viruses at specific concentrations (for analytical specificity/cross-reactivity).
• Testing with potential interfering substances at defined concentrations.

These analytical studies establish the performance characteristics that dictate how the device's inherent algorithms classify a result, rather than a separate "training set" of patient data.

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The Wondfo Strep A Rapid Test is a chromatographic immunoassay for the qualitative detection of Strep A antigen from throat swab specimens from symptomatic patients to aid in the diagnosis of Group A Streptococcal Infection. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use, only.

For in vitro diagnostic use For prescription Use only

Wondfo One Step Strep A Swab Test is a qualitative, lateral flow immunoassay for the detection of Strep A carbohydrate antigen directly from a throat swab sample. To perform the test. Reagent 1 (R 1) is added to the extraction tube which is coated with a mixture of conjugate antibodies and a lytic enzyme extraction reagent.

The lytic enzyme is mixed with colloidal gold conjugated to rabbit anti-Strep A and a second colloidal gold control conjugate antibody. The reagents are dried onto the bottom of an extraction tube forming a red spot. The extraction/conjugate pellet is re-suspended with RI and the throat swab is added to the extraction tube. The Strep A antigen is extracted from the sample and the swab is removed. The test strip is immediately placed in the extracted sample.

If Group A Streptococcus is present in the sample, it will react with the anti-Strep A antibody conjugated to the gold particle. The complex will then be bound by the anti-Strep A capture antibody and a visible red test line will appear, indicating a positive result. To serve as an onboard procedural control, the blue line observed at the control site prior to running the assay will turn red, indicating that the test has been performed properly. If Strep A antigen is not present, or present at very low levels, only a red control line will appear. If the red control line does not appear, or remains blue, the test result is invalid.

Acceptance Criteria and Study for Wondfo One Step Strep A Swab Test

This document outlines the acceptance criteria and the performance study for the Wondfo One Step Strep A Swab Test, a chromatographic immunoassay for the qualitative detection of Strep A antigen.

1. Table of Acceptance Criteria and Reported Device Performance

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

• Test Set (Clinical Study): A total of 349 throat swabs were collected.
  • 101 culture-positive specimens.
  • 248 culture-negative specimens.
• Data Provenance: The document does not explicitly state the country of origin. The study appears to be prospective, as samples were "collected from patients exhibiting symptoms of pharyngitis" and then tested by both culture and the Wondfo device.

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

• The ground truth for the clinical study was established by bacterial culture on sheep blood agar plates. It is a laboratory-based method of detecting bacterial presence, not based on expert interpretation of images or observations.
• Therefore, the concept of "number of experts" and "qualifications of those experts" in the traditional sense of medical image interpretation (e.g., radiologists) is not applicable here. The culture results are considered the objective ground truth.

4. Adjudication Method for the Test Set

• The ground truth was established by bacterial culture. This is an objective laboratory method, and thus, an adjudication method for reconciling differing results between experts is not applicable. The culture result is a definitive positive or negative.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, a MRMC comparative effectiveness study was not explicitly done. This study assesses the performance of a diagnostic device (rapid test) against a gold standard (bacterial culture), not how human readers improve with or without AI assistance.
• The document does not mention any AI component or human-in-the-loop assistance in the context of improving human reader performance.

6. Standalone Performance Study

• Yes, a standalone study was done. The entire clinical performance section (Section 10.3) details the performance of the Wondfo One Step Strep A Swab Test as an algorithm/device only, without human-in-the-loop performance being a variable. The rapid test results were directly compared to the bacterial culture results.

7. Type of Ground Truth Used

• The primary ground truth used for the clinical study was bacterial culture.
• For the analytical performance studies (precision, cut-off, interference, specificity), the ground truth was established using known concentrations of inactivated Streptococcus pyogenes or other specified organisms/substances.

8. Sample Size for the Training Set

• The document does not provide information on a specific training set or its sample size. This is a rapid diagnostic test, not a machine learning algorithm that typically requires a distinct training phase. All listed performance characteristics studies (analytical and clinical) appear to be validation or test sets for the finished device.

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

• As a training set is not explicitly mentioned for a machine learning model, the method for establishing its ground truth is not applicable in this context. The established ground truth for the analytical and clinical studies were bacterial culture and known concentrations of organisms/substances.

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The Sofia Strep A FIA employs immunofluorescence technology to detect Group A Streptococcal antigens from throat swabs of symptomatic patients. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.

The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia Analyzer to detect Group A Streptococcal antigens. The Sofia Strep A FIA is a lateral-flow immunoassay that uses polyclonal antibodies that are specific for Group A Streptococcal antigens. Throat swab specimens are used for this test. The patient specimen is placed in the Reagent Tube, during which time the bacteria in the specimen are disrupted, exposing Group A Streptococcal antigens. After disruption, the specimen is dispensed into the cassette sample well. From the sample well, the specimen migrates through a test strip containing various unique chemical environments. If the Group A Streptococcal antigen is present, they will be trapped in a specific location. Note: Depending upon the user's choice, the cassette is either placed inside of the Sofia Analyzer for automatically timed development (Walk Away Mode) or placed on the counter or bench top for a manually timed development and then placed into the Sofia Analyzer to be scanned (Read Now Mode). The Sofia Analyzer will scan the test strip and measure the fluorescent signal by processing the results using method specific algorithms. The Sofia Analyzer will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected.

Here's an analysis of the provided text regarding the acceptance criteria and study for the Sofia® Strep A FIA and Sofia Analyzer:

Note: The provided text lacks the explicit "acceptance criteria" and the full "study that proves the device meets the acceptance criteria" in terms of specific performance targets (e.g., sensitivity, specificity thresholds). It outlines the studies performed and then states a conclusion of "substantial equivalence" based on these studies. Therefore, the table below will present the reported device performance, and the "acceptance criteria" part will reflect an inferred benchmark based on the predicate device and the general aim of demonstrating substantial equivalence.

Acceptance Criteria and Device Performance Study for Sofia® Strep A FIA and Sofia Analyzer

1. Table of Acceptance Criteria and Reported Device Performance

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

• Sample Size for Test Set: The document mentions "A multi-center field clinical study" and "throat swab specimens" for sensitivity and specificity calculations. However, the exact number of specimens or sample size used for the clinical test set is not specified in this summary.
• Data Provenance: The document states "A multi-center field clinical study." The country of origin is not explicitly stated, but being a 510(k) submission to the FDA, it is highly probable that at least a significant portion, if not all, of the clinical data was collected in the United States. The study was prospective, as it was a "field clinical study" to document performance.

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

• The document does not explicitly state the number of experts used to establish the ground truth or their specific qualifications (e.g., "radiologist with 10 years of experience").
• However, for Strep A immunological tests, the ground truth is typically established by bacterial culture, which is considered the gold standard for diagnosis. Therefore, experts involved would likely be clinical microbiologists or laboratory personnel experienced in bacterial culture techniques and interpretation.

4. Adjudication Method for the Test Set

• The document does not specify an adjudication method (e.g., 2+1, 3+1, none) for the test set. Given that the ground truth for Strep A is generally established by bacterial culture, a consensus among human readers for image interpretation (as implied by adjudication in radiology studies) is not typically applicable in this context. The culture result itself serves as the definitive reference.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and the effect size of how much human readers improve with AI vs without AI assistance

• No, an MRMC comparative effectiveness study was not done as described for AI assistance in image interpretation. This device is an in vitro diagnostic (IVD) test that automates the reading of a lateral-flow immunoassay. It does not involve human readers interpreting images with or without AI assistance in the traditional sense of an MRMC study. The Sofia Analyzer is the "AI" or automated reader, replacing manual visual interpretation.

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

• Yes, a standalone study was done. The Sofia Strep A FIA, when used with the Sofia Analyzer, is designed for automated analysis. The "Read Results" feature states "Read results on instrument screen or print with optional printer" and "Automated Analysis: Yes." The analytical and clinical studies were performed to demonstrate the performance of this automated system directly, without a human-in-the-loop for result interpretation, beyond simply reading the result the analyzer provides.

7. The Type of Ground Truth Used

• The ground truth used for establishing clinical performance (sensitivity and specificity) was bacterial culture. The intended use statement explicitly directs: "All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment." This indicates that bacterial culture is the definitive reference method.

8. The Sample Size for the Training Set

• The document does not provide information on the sample size for a training set. For IVD devices like this, the "algorithm" is embedded in the Sofia Analyzer. While the algorithms would have been developed and refined using internal data, this summary focuses on the validation of the final device within clinical and analytical studies, not the development phase.

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

• As with the training set sample size, the document does not provide details on how the ground truth for any potential training set was established. Assuming there was an internal development phase, the ground truth for training data would likely also have been established using bacterial culture as the gold standard, similar to the method for the clinical validation studies.

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The BD Veritor" System for Rapid Detection of Group A Strep test is a rapid chromatographic immunoassay for the direct and qualitative detection of Group A Streptococcus antigen from throat swabs of symptomatic patients. It is intended to be used in conjunction with the BD Veritor™ System Reader as an aid in the diagnosis of Group A Strep. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment.

The BD Veritor System for rapid detection of Group A Strep test is intended for use in point-of-care or laboratory settings.

The BD Veritor™ System for rapid detection of Group A Strep is a qualitative, lateral flow immunoassay for the detection of Strep A carbohydrate antigen in a throat swab. In this test, antibody specific to Strep A carbohydrate antigen is coated on the test line region of the Assay device. During testing, the processed throat swab specimen reacts with an antibody to Strep A that is conjugated onto detector particles. The mixture migrates up the membrane to react with the antibody to Strep A on the membrane and is captured by the line of antibody on the membrane. A positive result for Strep A is determined by the BD Veritor ™ System Reader when antigen-conjugate is deposited at the Test "T" position and the Control "C" position on the BD Veritor™ System Strep A assay device.

Here's an analysis of the acceptance criteria and study detailed in the provided document for the BD Veritor™ System for Rapid Detection of Group A Strep:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria values for sensitivity and specificity. However, based on the Intended Use statement and the comparison to an existing predicate device, we can infer that the device aims for performance comparable to or better than current rapid chromatographic immunoassays for Group A Strep. Given the nature of a 510(k) submission, the "acceptance criteria" here are implicitly met by demonstrating substantial equivalence to the predicate and by achieving clinically acceptable performance metrics.

For the purpose of this response, I will list the observed performance metrics from the clinical study as the "reported device performance." If explicit acceptance criteria were given, they would typically be pre-specified thresholds (e.g., "Sensitivity > 85%", "Specificity > 95%").

Additional Performance Data (Analytical & Reproducibility):

• Strain 19615: 5 x 10^4 CFU/mL (96.7% positivity)
• Strain 25663: 2 x 10^5 CFU/mL (95.0% positivity) |
  | Analytical Specificity | - Lancefield Groups A, B, C, D, F, G (at 1x10^9 CFU/mL): Negative results (no cross-reactivity with other Streptococcus groups).
• Various bacteria and yeasts (e.g., Arcanobacterium haemolyticum, Candida albicans, E. coli, S. aureus) and viruses (e.g., Adenovirus, Cytomegalovirus, HSV, Influenza): No cross-reactivity observed. |
  | Interfering Substances | 40+ common substances found in respiratory samples (e.g., 4-Acetamidophenol, Acetylsalicylic acid, Albuterol, various blood types, nasal sprays, throat lozenges) tested at specified concentrations: None exhibited interference with Group A positive or Group A negative samples. |
  | Media Compatibility | Four transport media (Modified Amies, Modified Stuart's, Normal Saline, Phosphate Buffered Saline) and two agar types (Tryptic Soy Agar with 5% Sheep Blood, Selective Strep Agar) were compatible. Expected results were obtained, and acceptance criteria were met for room temperature and overnight frozen storage conditions. |
  | Reproducibility | - High negative sample: 1.1% false positive rate (1/90 samples across 3 sites).
• Low positive sample: 91.1% positivity (82/90 samples across 3 sites).
• Moderate positive sample: 98.9% positivity (89/90 samples across 3 sites).
• Negative sample: 0% false positive rate (0/90 samples across 3 sites). |

2. Sample Size and Data Provenance (Clinical Study)

• Sample Size for Test Set: 796 prospectively collected specimens.
• Data Provenance: The study was a multi-center clinical trial conducted at one clinical laboratory site and four Point-of-Care (POC) sites. The country of origin is not explicitly stated but is implicitly the USA, given the FDA 510(k) submission. The data was prospective.
• Patient Demographics:
  • Gender: 51.8% female, 48.2% male.
  • Age: 39.1% = 22 years old.

3. Number of Experts and Qualifications for Ground Truth (Clinical Study)

The document states that the performance was determined by comparison to bacterial culture. This implies that clinical laboratory professionals (e.g., microbiologists, medical technologists) conducted and interpreted the bacterial cultures, which served as the gold standard. The specific number of experts or their years of experience are not explicitly mentioned.

4. Adjudication Method for the Test Set (Clinical Study)

The document does not describe an explicit adjudication method (e.g., "2+1" or "3+1") for discrepancies between the device result and the bacterial culture. The bacterial culture itself is treated as the reference standard. Discrepancies would simply be counted as false positives or false negatives for the device.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, an MRMC comparative effectiveness study was not explicitly described in terms of human readers using the device with and without AI assistance.
• The study compares the device's performance (interpreted by the BD Veritor™ System Reader) against bacterial culture, which is a standalone assessment of the device's accuracy. The "Detection Format" section mentions an "opto-electronic reader determines the line intensity... interprets the results using the scoring algorithm, and reports a positive, negative, or invalid result," which indicates an automated interpretation, not a human reader decision with or without AI.
• Therefore, an effect size of how much human readers improve with AI vs. without AI assistance is not applicable/provided in this document.

6. Standalone Performance Study (Algorithm Only)

Yes, a standalone study was done. The entire clinical performance section evaluates the BD Veritor™ System (which includes the device and the associated reader/algorithm for interpretation) as a standalone diagnostic tool. The "opto-electronic reader" described in the device comparison section directly indicates algorithmic interpretation without human intervention for the final positive/negative result.

7. Type of Ground Truth Used (Clinical Study)

The type of ground truth used for the clinical study was bacterial culture (often referred to as the "gold standard" for Group A Strep diagnosis).

8. Sample Size for the Training Set

The document does not specify a separate training set or its sample size for the device's algorithm. It primarily details the clinical validation study (test set). For an IVD device like this, the "training" might involve internal development and optimization using characterized samples, but a dedicated clinical training set of patient samples is not typically reported in the same way as for AI/ML regulatory submissions.

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

As no specific training set of patient samples is detailed, the method for establishing its ground truth is not provided. If such a set were used during device development, its ground truth would likely also be established through bacterial culture or other highly reliable laboratory methods, similar to the clinical test set.

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The Clearview Advanced™ Strep A test is a rapid chromatographic immunoassay for the qualitative detection of Strep A antigen from throat swab specimens as an aid in the diagnosis of Group A Streptococcal infection.

The Clearview Advanced™ Strep A test is a qualitative, lateral flow immunoassay for the detection of Strep A carbohydrate antigen directly from a throat swab sample. To perform the test, Reagent 1 (R1) is added to the extraction tube which is coated with a mixture of conjugate antibodies and a lytic enzyme extraction reagent. The lytic enzyme is mixed with colloidal gold conjugated to rabbit anti-Strep A and a second colloidal gold control coniugate antibody. The reagents are dried onto the bottom of an extraction tube forming a red spot. The extraction/conjugate pellet is resuspended with R1 and the throat swab is added to the extraction tube. The Strep A antigen is extracted from the sample and the swab is removed. The test strip is immediately placed in the extracted sample. If Group A Streptococcus is present in the sample, it will react with the anti-Strep A antibody conjugated to the gold particle. The complex will then be bound by the anti-Strep A capture antibody and a visible red test line will appear, indicating a positive result. To serve as an onboard procedural control, the blue line observed at the control site prior to running the assay will turn red, indicating that the test has been performed properly. If Strep A antigen is not present, or present at very low levels, only a red control line will appear. If the red control line does not appear, or remains blue, the test result is invalid.

Here's a breakdown of the acceptance criteria and study details for the Clearview Advanced™ Strep A Test, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

• Diluent (True Negative): 0% (0/179)
• 1x10^5 (Moderate Positive): 99% (179/180)
• 1x10^4 (LOD/C95 Concentration): 94% (170/180)
• 3.2x10^3 (Near the cut-off/C50 Concentration): 49% (88/179) |

Note on Acceptance Criteria: The document does not explicitly state numerical acceptance criteria for sensitivity and specificity. However, regulatory bodies implicitly expect high performance from diagnostic tests for infectious diseases. The provided confidence intervals indicate a robust performance profile. For analytical sensitivity and specificity, the acceptance criteria are described directly in the text (e.g., "produces positive... approximately 95% of the time" for LOD, and "all... were negative" for cross-reactivity).

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

• Sample Size (Clinical Performance Test Set): A total of 297 throat swab specimens.
• Data Provenance:
  • Country of Origin: United States.
  • Retrospective or Prospective: Prospective clinical study.
  • Study Design: Multi-center study conducted in 2008-2009 at five geographically diverse physician offices, clinics, and emergency departments.

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

• The document does not specify the number of experts used to establish the ground truth or their qualifications. The ground truth ("bacterial culture") is an objective laboratory method rather than an expert interpretation in this context.

4. Adjudication Method for the Test Set

• The document does not describe an adjudication method. The comparison is directly between the Clearview Advanced Strep A test results and the bacterial culture results.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, an MRMC comparative effectiveness study was not done. This study assesses the performance of a device (immunoassay) against a gold standard (bacterial culture), not how human readers improve with or without AI assistance.

6. Standalone Performance Study

• Yes, a standalone performance study was done. The entire clinical performance section describes the algorithm's (device's) performance without human intervention in interpreting the test result. The test is a qualitative, lateral flow immunoassay where the visual appearance of a line directly indicates a positive or negative result, and its accuracy is compared to the bacterial culture.

7. Type of Ground Truth Used

• Bacterial Culture. The clinical performance of the Clearview Advanced Strep A test was established by comparing its results to bacterial culture, which is considered the gold standard for diagnosing Group A Streptococcal infection.

8. Sample Size for the Training Set

• The document does not specify a separate training set or its sample size. The description of the clinical study refers to the "test set" or "evaluation set" for performance metrics. For traditional immunoassay devices like this, there isn't typically a distinct "training set" in the machine learning sense. The device's design and parameters are developed through analytical studies (e.g., LOD, cross-reactivity) rather than through training on a large dataset of patient samples.

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

• Since there's no explicitly defined "training set" in the context of machine learning for this device, a ground truth establishment method for it is not applicable/not described. The robust design of the immunoassay, informed by analytical studies, serves as its "training" or development process.

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The StatusFirst™ Strep A is intended for use as an in vitro diagnostic product for the qualitative detection of group A streptococcal antigen directly from throat swab specimens. The test is intended for use in the physician's offices, hospitals, and clinical laboratories as an aid in the clinical diagnosis of group A streptococcal infection.

Not Found

This document is a 510(k) clearance letter for three different Strep A rapid diagnostic tests: StatusFirst™ Strep A, BioStrep® A, and BioSign® Strep A / Status AccuStrepA™. However, it does not contain the detailed study information regarding acceptance criteria and performance data. The letter only states that the devices are substantially equivalent to legally marketed predicate devices.

Therefore, I cannot provide the requested information from this document. The document primarily focuses on the regulatory clearance for the device, not the technical performance study details.

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The Inverness Medical TestPack + Plus Strep A with OBC Test is intended for the qualitative detection of Group A Streptococcal (Group A Strep) antigen in throat swab specimens from patients with suspected Group A Strep associated pharyngitis and for confirmation of presumptive Group A Strep colonies isolated on culture plates. The test is intended for Professional and Laboratory Use only.

Inverness Medical TestPack + Plus Strep A with OBC Strep A is an immunoassay employing sheep and rabbit polyclonal antibodies and gold colloid particles. The test device uses lateral flow technology; following antigen extraction, the test time is approximately 5 minutes. The Streptococcal Group A specific antigen is extracted from the throat swab using Reagent 1 (2.0 M Sodium Nitrite (& Xylenol Orange) and Reagent 2 (1.0 M Acetic Acid). Following this, Reagent 3 (1.0 M Tris Buffer) is added to neutralise the acid formed by Reagents 1 and 2. The mixture is then dropped into the sample well of the reaction disc from which it migrates through the membrane until it reaches the End of Assay (EOA) Window. As the specimen extract migrates through the membrane, it mobilises the antibody-coated colloid (colloid coated with Rabbit Anti-Strep A antibody). If Group A Streptococcal antigen is present in the specimen it will form a complex with the antibody-colloid. The antibody colloid complex migrates through the membrane and is then captured by the Group A Strep antibody (Sheep polyclonal antibody) in the result window, providing a visual indication of the presence of antigen. The test can be read when the 'End of Assay' (EOA) window has turned pink / red. A pink / red Plus Sign (+) appearing in the result window indicates the presence of the Group A Strep antigen. A Minus Sign (-) indicates no antigen was detected. The device also includes integral Control features.

Acceptance Criteria and Study Details for Inverness Medical TestPack + Plus Strep A with OBC

1. Table of Acceptance Criteria and Reported Device Performance

The provided document does not explicitly state pre-defined acceptance criteria with specific numerical thresholds for sensitivity and specificity. Instead, the study aimed to demonstrate "substantial equivalence" to established culture techniques and other commercially available products. The clinical performance data is presented below, representing the "reported device performance."

2. Sample Size and Data Provenance

The study was a "multi-centre study" conducted to evaluate clinical performance.

• Sample Size for Test Set: 1048 throat swab specimens.
• Data Provenance: The document does not explicitly state the country of origin. Given the submitter is from the United Kingdom, it's possible the study involved centers in the UK, but this is not confirmed. The study was "multi-centre," suggesting data from multiple locations.
• Retrospective or Prospective: Not explicitly stated, but the nature of a clinical performance study evaluating a diagnostic device typically implies prospective data collection from patients with suspected Group A Strep pharyngitis.

3. Number of Experts and their Qualifications for Ground Truth

• The ground truth was established by "established culture techniques." While it's implied that laboratory personnel with appropriate qualifications performed the culture methods and interpretations, the document does not specify the "number of experts" involved in establishing this ground truth, nor their specific "qualifications" beyond operating these established techniques.

4. Adjudication Method

Not applicable. The ground truth was based on culture results, which are objective laboratory findings, not subjective interpretations requiring adjudication.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, an MRMC comparative effectiveness study was not explicitly done to assess how much human readers improve with AI vs. without AI assistance.
• The document implies a physicians' office study was conducted to show that physician office personnel could correctly perform and interpret the results of the device (not an AI assistant). This is a study of user performance with the device, not an MRMC study comparing AI-assisted vs. unassisted human readings.

6. Standalone Performance Study

• Yes, a standalone study was done. The reported performance metrics (sensitivity, specificity, overall agreement) are for the device (algorithm only, in this context, the immunoassay device's output) without human interpretation added into the performance calculation, beyond reading the clear positive or negative result on the device.

7. Type of Ground Truth Used

• The primary ground truth used for the clinical performance evaluation was "established culture techniques" for Group A Strep.

8. Sample Size for the Training Set

• The document does not mention a training set or any details about it. This device is a lateral flow immunoassay that relies on chemical reactions and visual indicators, not a machine learning or AI algorithm that typically requires a large training dataset.

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

• Not applicable, as no training set for a machine learning model is mentioned or implied.

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Status First™ Strep A is an immunoassay for the qualitative detection of Group A Streptococcal antigen directly from throat swab specimens to aid in the early diagnosis of Group A Streptococcal infection.

Status First"" Strep A is an in vitro, simple, one step immunochromatographic diagnostic test for the rapid, qualitative detection of Group A Streptococcal antigen

1. Acceptance Criteria and Reported Device Performance:

The provided 510(k) summary does not explicitly state numerical acceptance criteria for the Status First™ Strep A device. Instead, the device's performance is established through substantial equivalence to a legally marketed predicate device, BioSign StrepA (K971349).

2. Sample Size for Test Set and Data Provenance:

   • Test Set Sample Size: Not specified. The document focuses on substantial equivalence based on product identity and manufacturing processes, rather than a new clinical performance study with a distinct test set.
   • Data Provenance: Not applicable for a new clinical performance study. The data provenance would be linked to the predicate device's original studies, which are not detailed here. The 510(k) refers to the predicate device BioSign StrepA, K971349.

3. Number of Experts and Qualifications:

   • Not applicable. The submission focuses on substantial equivalence, not a new clinical study requiring expert ground truth establishment for a test set.

4. Adjudication Method:

   • Not applicable. No new clinical performance study is described with a need for adjudication.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

   • No MRMC comparative effectiveness study was done or reported in this 510(k) summary. The submission is for an in-vitro diagnostic device, which typically involves analytical performance studies and comparison to a predicate, not human reader performance studies.

6. Standalone Performance:

   • Yes, in a way. The Status First™ Strep A is a standalone in-vitro diagnostic device. Its performance is implicitly the standalone performance as compared to the predicate device. However, a separate, new standalone performance study (i.e., with new data demonstrating accuracy, sensitivity, and specificity) is not detailed as part of this 510(k) submission. Its standalone performance is considered equivalent to the predicate.

7. Type of Ground Truth Used:

   • Not explicitly stated for Status First™ Strep A in this document, as a new performance study wasn't described. For the predicate device, BioSign StrepA, it would typically involve culture methods as the "gold standard" for diagnosing Group A Streptococcal infection to establish true positive/negative results.

8. Sample Size for Training Set:

   • Not applicable. This 510(k) does not describe an AI/machine learning device with a training set. It's an immunoassay.

9. How Ground Truth for Training Set Was Established:

   • Not applicable, as there is no training set for this type of immunoassay device.

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