(116 days)
The Binax NOW Streptococcus pneumoniae Test is an in vitro rapid immunochromatographic assay for the detection of Streptococcus pneumoniae (S. pneumoniae) antigen in the urine of patients with pneumonia and in the cerebral spinal fluid (CSF) of patients with meningitis. It is intended, in conjunction with culture and other methods, to aid in the presumptive diagnosis of both pneumococcal pneumonia and pneumococcal meningitis.
The Binax NOW Streptococcus pneumoniae Test is an immunochromatographic membrane assay used to detect pneumococcal soluble antigen in human urine and CSF. Rabbit anti-S. pneumoniae antibody, the Sample Line, is adsorbed onto nitrocellulose membrane. Control antibody is adsorbed onto the same membrane as a second stripe. Both rabbit anti-S. pneumoniae and anti-species antibodies are conjugated to visualizing particles that are dried onto an inert fibrous support. The resulting conjugate pad and striped membrane are combined to construct the test strip. This test strip and a well to hold the swab specimen are mounted on opposite sides of a hinged, book-shaped test device (U.S. patent No. 2 U.S. 91/214051). To perform the test (2 U.S. patents pending), a swab is dipped into the specimen, removed, and then inserted into the test device. Reagent A, a buffer solution, is added from a dropper bottle. The device is then closed, bringing the sample into contact with the test strip. Pneumococcal antigen present in the sample reacts to bind anti-S. pneumoniae conjugate antibody. The resulting antigen-conjugate complexes are captured by immobilized anti-S. pneumoniae antibody, forming the Sample Line. Immobilized control antibody captures anti-species conjugate, forming the Control Line. There are no transferring steps, the sample is contained, and results are available within 15 minutes.
Here's an analysis of the provided text regarding the Binax NOW Streptococcus pneumoniae Test, focusing on the acceptance criteria and the study details:
Acceptance Criteria and Study Details for Binax NOW Streptococcus pneumoniae Test
1. Table of Acceptance Criteria and Reported Device Performance
The provided text focuses on the performance of the device in comparison to a predicate device, rather than explicit numerical acceptance criteria for sensitivity, specificity, or predictive values. The primary acceptance criterion implied is "substantial equivalence" to the predicate device, the Wellcogen Bacterial Antigen Kit (K854852).
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Substantial Equivalence to Predicate Device (Wellcogen Bacterial Antigen Kit) for detection of S. pneumoniae antigen in CSF of patients with meningitis. | The Binax NOW Streptococcus pneumoniae Test is stated to be "substantially equivalent to the predicate device, the Wellcogen Bacterial Antigen Test (K854852), for the detection of S. pneumoniae antigen in urine and CSF." |
Regarding CSF, the application "focusses on performance of the Binax Now Streptococcus pneumoniae Test in diagnosis of meningitis." The performance study was done using freshly-collected CSF specimens. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample size used for the test set related to the CSF meningitis application. It only mentions that the study used "freshly-collected CSF specimens."
The document does not specify the country of origin. The study appears to be prospective given the mention of "freshly-collected CSF specimens."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not provide information on the number of experts used or their qualifications for establishing the ground truth of the test set.
4. Adjudication Method for the Test Set
The document does not specify any adjudication method used for the test set.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
The document does not mention an MRMC comparative effectiveness study involving human readers. The comparison is between two in-vitro diagnostic devices (Binax NOW and the Wellcogen predicate device).
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
Yes, the study described is a standalone performance study of the Binax NOW Streptococcus pneumoniae Test. This is an in vitro diagnostic assay that provides a visual result, which is then interpreted by a human, but the performance evaluation is of the test's ability to detect the antigen itself.
7. The Type of Ground Truth Used
The ground truth used for the study is culture and other methods. The intended use states that the test acts "in conjunction with culture and other methods, to aid in the presumptive diagnosis of both pneumococcal pneumonia and pneumococcal meningitis." This implies that bacterial culture results from CSF samples would be the primary ground truth, supplemented by other clinical and laboratory findings.
8. The Sample Size for the Training Set
The document does not provide any information regarding a training set or its sample size. This type of in vitro diagnostic device, especially at this stage of development (immunochromatographic assay), typically does not involve machine learning models with distinct "training sets" in the modern sense. The development and optimization of such assays rely on biochemical and immunological principles, followed by performance validation against clinical samples.
9. How the Ground Truth for the Training Set Was Established
As no training set is described in the context of machine learning, this question is not applicable based on the provided document. The ground truth for the performance evaluation (test set) is established through "culture and other methods."
§ 866.3740
Streptococcus spp. serological reagents.(a)
Identification. Streptococcus spp. serological reagents are devices that consist of antigens and antisera (excluding streptococcal exoenzyme reagents made from enzymes secreted by streptococci) used in serological tests to identifyStreptococcus spp. from cultured isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by bacteria belonging to the genusStreptococcus and provides epidemiological information on these diseases. Pathogenic streptococci are associated with infections, such as sore throat, impetigo (an infection characterized by small pustules on the skin), urinary tract infections, rheumatic fever, and kidney disease.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.