(88 days)
The AMPLICOR CT/NG test for Chlamydia trachomatis is a qualitative in vitro test for the detection of C. trachomatis DNA in urine from symptomatic or asymptomatic males, in endocervical swab specimens from symptomatic or asymptomatic females, and in urethral swab specimens from symptomatic males as evidence infection with C. trachomatis. C. trachomatis DNA is detected by Polymerase Chain Reaction (PCR) amplification of target DNA and by hybridization capture of amplified target using the AMPLICOR analyzer.
Roche Scripts for AMPLICOR CT/NG Test: The Roche Scripts for AMPLICOR CT/NG Test are intended to provide software scripts to direct the automated Tecan Genesis RSP 150 Workstation to process swab samples or control material for analysis using either of the following 510(k)-cleared assay test systems:
- AMPLICOR® CT/NG test for Chlamydia trachomatis
- AMPLICOR® CT/NG test for Neisseria gonorrhoeae
Sample and control preparation can either be accomplished manually or automated using the optional Roche Scripts for AMPLICOR CT/NG Test accessory to direct the Tecan Genesis RSP 150 workstation. Urine specimens are not indicated for use with the automated sample preparation option.
The AMPLICOR CT/NG test for Chlamydia trachomatis is a qualitative in vitro test for the detection of C. trachomatis DNA in urine from symptomatic or asymptomatic males, in endocervical swab specimens from symptomatic or asymptomatic females, and in urethral swab specimens from symptomatic males as evidence infection with C. trachomatis. C. trachomatis DNA is detected by Polymerase Chain Reaction (PCR) amplification of target DNA and by hybridization capture of amplified target using the AMPLICOR analyzer. The Roche Scripts for AMPLICOR CT/NG Test accessory consists of a compact disc (CDs) containing scripts to direct the automated Tecan Genesis RSP 150 workstation to process swab samples or control material for analysis.
This document focuses on the AMPLICOR CT/NG test for Chlamydia trachomatis with optional Roche Scripts for AMPLICOR CT/NG Test Accessory. The primary purpose of the Roche Scripts accessory is to automate the specimen preparation procedure for the existing AMPLICOR CT/NG test. The study therefore aims to demonstrate that the automated preparation method yields equivalent performance to the manual preparation method for the detection of C. trachomatis.
Here's the breakdown of the acceptance criteria and study details based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly list "acceptance criteria" in a quantitative format with specific thresholds to be met. Instead, it states that the performance characteristics were "evaluated" and "results were equivalent to those obtained with manual specimen preparation." The table below summarizes the listed performance characteristics from the "Comparison - similarities" section, indicating that these were similar or equivalent to the predicate device, which used manual preparation. For the "Current Device (automated preparation)" column, the provided values are the reported performance characteristics where they differ or are newly reported for the automated process.
| Feature | Acceptance Criteria (Implied: Equivalent to Manual Preparation) | Reported Device Performance (Automated Preparation) |
|---|---|---|
| Analytical Sensitivity | 1 IFU/test (manual) | 20 IFU/mL for CTM with swab specimen |
| Precision | 100% correct results (manual) | 99.6% correct results for panels of CTM specimens |
| Clinical Performance | Sensitivity vs. culture: 94.1% (females), 92.9% (males) (manual) | 98.5% concordance with manual method |
| Specificity vs. culture: 98.4% (females), 94.7% (males) (manual) | (Not explicitly stated; implied to be covered by concordance) | |
| Analytical Specificity | Negative results from a range of organisms (manual) | Same (implied) |
Note: The phrase "Results were equivalent to those obtained with manual specimen preparation" in the "Performance Evaluation" section suggests the overarching acceptance criterion was non-inferiority or equivalence to the established manual method.
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample size used for the clinical evaluation test set where the automated preparation method was compared to the manual method. It only states "A clinical evaluation was performed".
Data Provenance: The document does not specify the country of origin. It is a premarket notification to the FDA, suggesting the studies were conducted to support US regulatory approval. The studies are retrospective, comparing the automated preparation method with the established manual preparation method.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
This information is not provided in the document. For diagnostic tests like this, the 'ground truth' for clinical samples would typically be established by culture or a combination of clinical diagnosis and other accepted laboratory methods, not usually by a panel of experts reviewing images or results. The analytical studies would have ground truth established by known concentrations of organisms.
4. Adjudication Method for the Test Set
The document does not explicitly describe an "adjudication method" in the context of expert review. Clinical performance is assessed against a comparator (manual method and potentially culture), not through adjudicated expert consensus on each case.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. This type of study is typically for image-based diagnostic aids where human readers interpret results. The AMPLICOR CT/NG test is an in vitro diagnostic test that provides a qualitative (positive/negative) result; therefore, an MRMC study is not applicable. The comparison here is between two sample preparation methods for the same assay.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
This device is an in vitro diagnostic test for detecting DNA. The "Roche Scripts accessory" automates a part of the sample preparation process for an existing, already cleared assay. Therefore, the "algorithm" (scripts) performs an automated laboratory task, not an independent diagnostic interpretation that would involve a "human-in-the-loop" once the assay is run. The overall test is an "algorithm only" in the sense that the assay itself generates a direct result. The study effectively evaluated the standalone performance of the automated sample preparation system in generating results that are equivalent to manual preparation.
7. The Type of Ground Truth Used
For the analytical studies (analytical sensitivity, specificity, precision), the ground truth is established by known concentrations or presence/absence of C. trachomatis (or other organisms for specificity) in laboratory-prepared samples.
For the clinical evaluation, the ground truth for C. trachomatis infection status in patient samples is likely based on:
- Comparison to the manual preparation method of the AMPLICOR CT/NG test itself (labeled as "98.5% concordance with manual method"). This serves as a reference for equivalence, assuming the manual method's clinical performance is validated.
- The predicate device's clinical performance also references "Sensitivity vs. culture" and "Specificity vs. culture". This indicates that bacterial culture was a key ground truth method for validating the diagnostic accuracy of the PCR test itself.
8. The Sample Size for the Training Set
The document does not specify a separate "training set" or its sample size. This is a premarket submission for an in vitro diagnostic (IVD) device, where the focus is on validation and verification of analytical and clinical performance through predefined studies, not typically on machine learning model training. The "Roche Scripts" are software for automation, not an AI/ML diagnostic algorithm that would require a distinct training phase.
9. How the Ground Truth for the Training Set Was Established
As there is no distinct "training set" in the context of an AI/ML model for this IVD device (the scripts automate a lab process), the concept of ground truth for a training set does not directly apply here. The existing knowledge and performance characteristics of the manual AMPLICOR CT/NG test would have informed the development and optimization of the automated scripts to ensure equivalent performance.
§ 866.3120 Chlamydia serological reagents.
(a)
Identification. Chlamydia serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to chlamydia in serum. Additionally, some of these reagents consist of chlamydia antisera conjugated with a fluorescent dye used to identify chlamydia directly from clinical specimens or cultured isolates derived from clinical specimens. The identification aids in the diagnosis of disease caused by bacteria belonging to the genusChlamydia and provides epidemiological information on these diseases. Chlamydia are the causative agents of psittacosis (a form of pneumonia), lymphogranuloma venereum (a venereal disease), and trachoma (a chronic disease of the eye and eyelid).(b)
Classification. Class I (general controls).