(120 days)
The GONOSTAT® Gonococcal Detection Kit is indicated for the presumptive detection of Neisseria gonorrhoeae based on the detection of gonococcal DNA in female endocervical and male urethral specimens. Because of some cross-reactivity with DNA from N. meningitidis and some other members of the genus Neisseria, the test cannot be used with rectal or throat specimens.
The device is a modification of the predicate device which is also marketed by Sierra Diagnostics, Inc. The device labeling was changed to reflect the results of additional clinical studies that support claims for the use of the device in low prevalence female populations.
Acceptance Criteria and Study for Sierra Diagnostics, Inc. GONOSTAT® Gonococcal Detection Kit
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly state pre-defined acceptance criteria (e.g., "The device must achieve X% sensitivity"). However, the clinical study results are presented, and the FDA's clearance of the device implies that these results were deemed acceptable for the intended use and for demonstrating substantial equivalence to the predicate device. For the purpose of this analysis, the reported clinical study results for female endocervical specimens will be considered the target performance that was accepted by the FDA.
| Metric | Reported Device Performance (Female Endocervical Specimens) | Implied Acceptance Criteria (Based on FDA Clearance) |
|---|---|---|
| Sensitivity | 98.3% | 98.3% or higher (implicitly accepted by FDA) |
| Specificity | 99.3% | 99.3% or higher (implicitly accepted by FDA) |
| Predictive Value Positive | 94.4% | 94.4% or higher (implicitly accepted by FDA) |
| Predictive Value Negative | 99.8% | 99.8% or higher (implicitly accepted by FDA) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: N = 3318 (female endocervical specimens)
- Data Provenance:
- Country of Origin: Not explicitly stated in the provided text, but inferred to be within the United States given the FDA submission.
- Retrospective or Prospective: The study is described as an "additional clinical study" that was "performed using endocervical specimens at five study sites." This phrasing typically implies a prospective collection of new data for the purpose of the study.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided in the given text. The document refers to "clinical studies," but does not detail how the true positive or true negative cases were confirmed (i.e., the ground truth method and who established it).
4. Adjudication Method for the Test Set
This information is not provided in the given text.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size of Human Readers' Improvement with AI vs. Without AI Assistance
- MRMC Study: This device is a diagnostic kit for the detection of Neisseria gonorrhoeae DNA, not an AI-assisted diagnostic tool for image interpretation. Therefore, a Multi-Reader Multi-Case (MRMC) study involving human readers and AI assistance is not applicable and was not done.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Standalone Performance: Yes, the reported performance metrics (Sensitivity, Specificity, PPV, NPV) are for the GONOSTAT® Gonococcal Detection Kit operating as a standalone diagnostic assay. This kit directly detects gonococcal DNA; it is not an algorithm that requires human-in-the-loop interaction for interpretation, beyond standard laboratory procedures for running the test and reading the results. The "device performance" refers to the output of the kit itself.
7. The Type of Ground Truth Used
This information is not explicitly stated in the provided text. For a diagnostic test like this, the ground truth would typically be established by a reference method, which could include:
- Bacterial culture (gold standard for N. gonorrhoeae)
- Another validated molecular test
- Clinical diagnosis based on symptoms and other laboratory findings
However, the document does not specify which reference method was used to establish the true disease status of the 3318 specimens.
8. The Sample Size for the Training Set
This information is not applicable for this device submission as it is described. The GONOSTAT® Gonococcal Detection Kit is a DNA detection kit, not an AI/machine learning algorithm that requires a "training set" in the conventional sense of computational models. The "modification" mentioned refers to labeling changes based on additional clinical studies, not an update to a learned model.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable as there is no mention of a training set for an AI/machine learning model.
§ 866.3390
Neisseria spp. direct serological test reagents.(a)
Identification. Neisseria spp. direct serological test reagents are devices that consist of antigens and antisera used in serological tests to identifyNeisseria spp. from cultured isolates. Additionally, some of these reagents consist ofNeisseria spp. antisera conjugated with a fluorescent dye (immunofluorescent reagents) which may be used to detect the presence ofNeisseria spp. directly from clinical specimens. The identification aids in the diagnosis of disease caused by bacteria belonging to the genusNeisseria, such as epidemic cerebrospinal meningitis, meningococcal disease, and gonorrhea, and also provides epidemiological information on diseases caused by these microorganisms. The device does not include products for the detection of gonorrhea in humans by indirect methods, such as detection of antibodies or of oxidase produced by gonococcal organisms.(b)
Classification. Class II (performance standards).