(210 days)
The FemExam® TestCard™ contains two qualitative, colorimetric tests for use in the characterization of a vaginal fluid sample: (1) a pH test that differentiates vaginal fluid pH less than pH 4.7 from vaginal fluid pH equal to or greater than pH 4.7; and (2) a test that detects alkali volatilizable amines in vaginal fluid.
The FemExam® TestCard™ contains two qualitative, colorimetric tests: a pH test and an amine test. The pH test uses nitrazine yellow to produce a visual color change within two minutes of specimen application, indicating pH less than or greater than 4.7. It includes a positive procedural control and a negative background control. The amine test uses bromocresol green (BCG) and sodium aluminate to produce a visual color change within two minutes of specimen application, indicating the presence of alkali volatilizable amines. It also includes a positive procedural control and a negative background control.
The provided text describes the FemExam® TestCard™, a device with two qualitative, colorimetric tests for vaginal fluid: a pH test and an amine test. The information needed for a comprehensive study description, such as specific acceptance criteria and detailed performance data, sample sizes, and ground truth establishment for training, is not fully available in the provided text. However, based on the given information, here's an attempt to structure the answer:
Device: FemExam® TestCard™ pH and Amine Tests
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state numerical acceptance criteria (e.g., minimum sensitivity, specificity, or agreement percentages). However, it reports statistically significant overall agreement for both tests.
| Acceptance Criteria (Implicit) | Reported Device Performance (pH Test) | Reported Device Performance (Amine Test) |
|---|---|---|
| Demonstrate "statistically significant overall agreement" with a reference method. | Statistically significant overall agreement with ColorpHast® pH test strip. | Statistically significant overall agreement with the whiff test. |
| Positive Agreement (Accuracy) | Calculated | Calculated |
| Negative Agreement (Accuracy) | Calculated | Calculated |
| Overall Agreement (Accuracy) | Calculated | Calculated |
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: Not specified. The document only mentions "a statistically designed clinical study."
- Data Provenance: Not specified (e.g., country of origin, retrospective or prospective). It is a clinical study, suggesting prospective data collection, but this is not explicitly stated.
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)
- pH Test Ground Truth: The ground truth was established by comparing to a "commercial pH test strip (ColorpHast® pH test strip) routinely used in clinical studies to estimate vaginal fluid pH." No experts are explicitly mentioned for this ground truth.
- Amine Test Ground Truth: The ground truth was established by comparing to "the whiff test, an accepted clinical standard for ascertaining volatile vaginal fluid amines." While the whiff test is a clinical standard, the number and qualifications of individuals performing and interpreting the whiff test (who would effectively be establishing ground truth) are not provided.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not specified. The document does not describe any adjudication process for the results of either the FemExam® TestCard™ or the reference methods.
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
This is not applicable to the FemExam® TestCard™. This device is a diagnostic test kit, not an AI assistance tool for human readers. It provides direct qualitative results.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, this was a standalone performance study. The FemExam® TestCard™ itself generates qualitative colorimetric results (blue plus/minus signs against specific backgrounds) that are interpreted directly. There doesn't appear to be a human-in-the-loop interpretation that significantly alters the test's outcome; rather, the test provides a direct result.
7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)
- pH Test: A commercial pH test strip (ColorpHast® pH test strip), which serves as a widely accepted clinical reference method for pH estimation.
- Amine Test: The whiff test, which is an "accepted clinical standard for ascertaining volatile vaginal fluid amines."
8. The sample size for the training set
Not applicable. The FemExam® TestCard™ is a chemical assay kit, not a machine learning model. Therefore, there is no "training set" in the context of AI/ML.
9. How the ground truth for the training set was established
Not applicable, as there is no training set for this type of device.
§ 862.1550 Urinary pH (nonquantitative) test system.
(a)
Identification. A urinary pH (nonquantitative) test system is a device intended to estimate the pH of urine. Estimations of pH are used to evaluate the acidity or alkalinity of urine as it relates to numerous renal and metabolic disorders and in the monitoring of patients with certain diets.(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 § 862.9.