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The Sofia RSV FIA employs immunofluorescence for detection of respiratory syncytial virus (RSV) nucleoprotein antigen in nasopharyngeal swab and nasopharyngeal aspirate/wash specimens taken directly from symptomatic patients. This qualitative test is intended for use as an aid in the rapid diagnosis of acute RSV infections in pediatric patients less than 19 years of age. Negative results do not preclude RSV infection and should not be used as the sole basis for treatment or for other management decisions. A negative result is presumptive, and it is recommended these results be confirmed by virus culture or an FDA-cleared RSV molecular assay.

The Sofia RSV FIA test employs immunofluorescence technology that is used with the Sofia Analyzer for the rapid detection of RSV antigens. The Sofia RSV FIA test involves the disruption of RSV viral antigens. The patient specimen is placed in the Reagent Tube, during which time the virus particles in the specimen are disrupted, exposing internal viral nucleoproteins. 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 RSV viral antigens are 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.

The provided text describes the 510(k) summary for the Sofia® RSV FIA device, but it does not contain the specific acceptance criteria or the detailed results of the multi-center field clinical study that would allow for a complete table of acceptance criteria and reported device performance. The summary mentions that "Sensitivity and specificity were calculated" but does not provide the actual values or the criteria they were measured against.

Therefore, I cannot fulfill Request 1 directly from the provided text. I will answer the other requests based on the available information.

Here's a breakdown of the information that can be extracted and a note on what is missing:

1. A table of acceptance criteria and the reported device performance

MISSING: The document states that "Sensitivity and specificity were calculated" in the multi-center field clinical study, but it does not report the actual sensitivity and specificity values, nor does it specify any pre-defined acceptance criteria that these values were compared against. Without these numbers, a table cannot be created.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

• Sample Size for Test Set: Not explicitly stated in terms of a specific number of patients or specimens for the multi-center field clinical study. It only mentions that "nasopharyngeal swab and nasopharyngeal aspirate/wash specimens, both fresh and after storage in transport media" were used.
• Data Provenance:
  • Country of Origin: Not specified.
  • Retrospective or Prospective: The study is described as a "multi-center field clinical study," which generally implies a prospective collection of data in a real-world clinical setting.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

MISSING: The document does not specify the number of experts used or their qualifications for establishing the ground truth for the clinical study.

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

MISSING: The document does not describe any adjudication method used for the test set.

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

NOT APPLICABLE/NOT PERFORMED: The Sofia RSV FIA is an instrumented immunofluorescence assay, not an AI-based diagnostic image analysis device or a system requiring human interpretation with or without AI assistance in the way an MRMC study would typically evaluate. The Sofia Analyzer processes results using "method-specific algorithms" and displays "Positive, Negative, or Invalid" results. The study described focuses on the device's analytical and clinical performance against a predicate device, not on human reader performance.

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

YES (Implicitly): The device functions as a standalone diagnostic. The Sofia Analyzer "scans the test strip and measures the fluorescent signal by processing the results using method-specific algorithms" to display "Positive, Negative, or Invalid" results. This is an algorithmic determination without direct human interpretation of the underlying signal, fitting the definition of standalone performance. The clinical study evaluated the performance of this system (device + analyzer algorithm) against a reference standard.

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

The intended use statement specifies that "Negative results do not preclude RSV infection and should not be used as the sole basis for treatment or for other management decisions. A negative result is presumptive, and it is recommended these results be confirmed by virus culture or an FDA-cleared RSV molecular assay."

Based on this, it is highly probable that the ground truth for the clinical study was established by either virus culture or an FDA-cleared RSV molecular assay as a reference method. The document implicitly supports this by recommending these methods for confirmation of negative results.

8. The sample size for the training set

NOT APPLICABLE/NOT PROVIDED: The document does not mention a "training set" in the context of machine learning. The device is an immunofluorescence assay with an analyzer that processes results using "method-specific algorithms." These algorithms are likely pre-programmed and validated, rather than being "trained" on a large dataset in the sense of deep learning models. The studies described are for analytical validation and clinical performance evaluation.

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

NOT APPLICABLE/NOT PROVIDED: As no "training set" for a machine learning algorithm is discussed, this information is not applicable.

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