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The Cepheid Xpert® CT/NG Control Panel is intended for use as an external assayed positive and negative quality control to monitor the performance of in vitro laboratory nucleic acid testing procedures for the qualitative detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) performed with the Cepheid Xpert® CT/NG assay on the GeneXpert® Instrument System. The controls consist of cultured and inactivated Chlamydia trachomatis and Neisseria gonorrhoeae as the positive control and human cells as the negative control.

The Cepheid Xpert® CT/NG Control Panel is not intended to replace manufacturer controls provided with the device.

The Cepheid Xpert® CT/NG Control Panel is used to monitor the extraction, amplification and detection of the Cepheid Xpert® CT/NG Assay. The Cepheid Xpert® CT/NG Control Panel contains authentic pathogens inactivated by radiological or temperature treatments. Each Cepheid Xpert® CT/NG Control Panel consists of 6 individually packaged positive control swabs and 6 individually wrapped negative control swabs. Each positive control swab contains Chlamydia trachomatis and Neisseria gonorrhoeae as well as preservatives and stabilizers. Each negative control swab contains human cells as well as preservatives and stabilizers. Each swab is individually wrapped with a desiccant in a heat-sealed foil pouch.

The provided text describes the acceptance criteria and performance data for the Cepheid Xpert® CT/NG Control Panel, which is an assayed quality control material for clinical microbiology assays. This is a diagnostic device, not an AI/ML-based device, so many of the requested criteria related to AI/ML studies (such as MRMC studies, training set details, or ground truth establishment by experts for imaging) are not applicable.

Here's an analysis based on the provided document:

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

The acceptance criteria for this device appear to be 100% agreement with expected results for both positive and negative controls. The reported device performance met these criteria.

• C. trachomatis: 92/92 (100%)
• N. gonorrhoeae (NG2): 92/92 (100%)
• N. gonorrhoeae (NG4): 92/92 (100%)
• SPC: 92/92 (100%) |
  | Negative Controls: 100% agreement with expected negative results for all analytes (SAC, SPC) | 100% agreement for all analytes:
• SAC: 97/97 (100%)
• SPC: 97/97 (100%) |
  | Consistency in Ct values across sites and operators (implied by %CV data) | Mean Ct and %CV values were reported across sites, demonstrating consistency. (e.g., Overall Mean Ct for C. trachomatis 31.8 (3.8)). |

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

• Test Set Sample Size:
  • Positive Controls: 92 replicates were tested across three sites. (31 from Site 1, 31 from Site 2, 30 from Site 3, with some additional runs for re-tests).
  • Negative Controls: 97 replicates were tested across three sites. (33 from Site 1, 34 from Site 2, 30 from Site 3, with some additional runs for re-tests).
• Data Provenance: The data was generated prospectively through a multi-site evaluation. The document does not specify the country of origin of the testing sites, but given it's an FDA submission, it's highly likely to be within the US or under US regulatory guidelines.

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

This is an in vitro diagnostic (IVD) device, specifically a quality control. The "ground truth" is inherent to the control material itself (i.e., the positive control contains the target microbes at a known concentration, and the negative control does not).

Therefore:

• Number of experts: Not applicable in the context of human interpretation for ground truth. The "ground truth" is established by the known composition of the control material (inactivated pathogens for positive, human cells only for negative).
• Qualifications of experts: Not applicable.

4. Adjudication method for the test set

Not applicable for an IVD quality control device. The results are quantitative (Ct values) and qualitative (positive/negative detection) based on the instrument's algorithm, not human interpretation requiring adjudication. Any "ERROR" or "INVALID" results were retested according to the Instructions for Use, which is a standard procedure for IVD testing.

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. This is an IVD quality control device, not an AI/ML imaging or diagnostic aid for human readers.

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

This device evaluates the performance of the Cepheid Xpert® CT/NG assay and GeneXpert® Instrument System, which is an automated system. The performance data presented demonstrates the "standalone" or "algorithm only" performance of the control panel interacting with the assay/instrument system as intended, without human interpretation as a variable.

7. The type of ground truth used

The ground truth is based on the known composition of the control materials:

• Positive control: Contains cultured and inactivated Chlamydia trachomatis and Neisseria gonorrhoeae.
• Negative control: Contains human cells.

The "expected results" (positive or negative) are determined by these known compositions.

8. The sample size for the training set

Not applicable. This is a manufactured control material, not an AI/ML algorithm that requires a training set. Its development involves formulation and manufacturing processes, followed by validation and verification studies (which are described as the "performance data").

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

Not applicable, as there is no "training set" in the AI/ML sense for this type of device. The "ground truth" for the control material itself is established during its design and manufacturing by precisely controlling its components.

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