(16 days)
AimStep™ Combo Pregnancy is intended for the rapid qualitative identification of hCG (human Chorionic Gonadotropin) in serum or urine to aid in the early determination of pregnancy. This test is for professional use.
The test utilizes a combination of monoclonal and polyclonal antibodies to selectively detect elevated levels of hCG. The assay is conducted by adding specimen to the test device and observing for the formation of colored lines. The specimen migrates via capillary action along the membrane to react with the colored coningate. Positive specimens react with the specific antibody-hCG-colored conjugate and form a colored line in the Specimen Area of the membrane. Absence of this colored line suggests a negative result. To serve as a procedural control, a colored line in the Control Area will always appear regardless of the presence or absence of hCG.
Here's an analysis of the provided text regarding the AimStep™ Combo Pregnancy device's acceptance criteria and studies:
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly defined by the device demonstrating "100% concordance" with a "commercially available serum/urine membrane test." The performance is reported as follows:
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| 100% concordance with a commercially available test for urine specimens | Urine Specimens: |
- AimStep™ Combo: 71 Positive, 88 Negative
- Commercially Available Test: 71 Positive, 88 Negative
- Concordance: 100% |
| 100% concordance with a commercially available test for serum specimens | Serum Specimens: - AimStep™ Combo: 21 Positive, 51 Negative, 1 Inconclusive
- Commercially Available Test: 21 Positive, 51 Negative, 1 Inconclusive
- Concordance: 100% |
| Detection of hCG concentrations of 20 mIU/ml and greater, standardized to the World Health Organization Third International Standard | The test "detects hCG concentrations of 20 mIU/ml and greater." "The test has been standardized to the World Health Organization Third International Standard." |
| No cross-reactivity with hLH, hFSH, and hTSH | "The addition of hLH (500 mIUml), hFSH (1000 mIU/ml), and hTSH (1000 ulU/ml) to negative and positive serum and urine specimens showed no cross-reactivity." |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size:
- Urine specimens: 159
- Serum specimens: 73
- Total specimens: 232
- Data Provenance: The study was a "multi-center clinical evaluation." The country of origin is not explicitly stated, but the submission is to the US FDA, implying at least some relevance to the US. The study is retrospective, as it compared results obtained using the AimStep™ Combo Pregnancy and another commercially available test, suggesting these specimens were likely previously collected and tested, or tested concurrently as part of a comparative evaluation rather than a de novo prospective collection for the AimStep device alone.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not explicitly state the number of experts or their qualifications. The ground truth for the comparison was established by the "results obtained using another commercially available serum/urine membrane test." This implies that the 'ground truth' was essentially the result from the predicate device, not necessarily an independent expert panel review of clinical outcomes or pathology.
4. Adjudication Method for the Test Set
The document does not describe an adjudication method for disagreements. Since the study reported "100% concordance," it's possible there were no disagreements, or any disagreements were resolved in an unstated manner, or specimens leading to disagreement were simply excluded.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, an MRMC comparative effectiveness study was not done. This was a comparison between two devices, not between human readers with and without AI assistance. The AimStep™ Combo Pregnancy is a qualitative rapid diagnostic test, not an AI-based diagnostic tool that assists human readers.
6. Standalone (Algorithm Only) Performance Study
- Yes, a standalone performance study was done. The device itself, which functions as a qualitative rapid diagnostic test (an "algorithm" in a very broad sense, as it interprets color changes), was evaluated independently of human interpretation influence beyond reading the result. Its performance was measured by its ability to correctly identify hCG and its concordance with a predicate device.
7. Type of Ground Truth Used
The primary ground truth used for the comparative clinical evaluation was the results obtained from a "commercially available serum/urine membrane test." Additionally, the device's analytical performance (detection limit and cross-reactivity) was evaluated against established standards (WHO Third International Standard) and specific known concentrations of related hormones.
8. Sample Size for the Training Set
The document does not mention a training set or any training process for the AimStep™ Combo Pregnancy device. This type of diagnostic device, based on immunoassay, is typically developed through analytical chemistry and immunoassay design, rather than machine learning requiring a "training set" of data.
9. How the Ground Truth for the Training Set Was Established
As no training set is mentioned, this question is not applicable to the provided information.
§ 862.1155 Human chorionic gonadotropin (HCG) test system.
(a)
Human chorionic gonadotropin (HCG) test system intended for the early detection of pregnancy —(1)Identification. A human chorionic gonadotropin (HCG) test system is a device intended for the early detection of pregnancy is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class II.(b)
Human chorionic gonadotropin (HCG) test system intended for any uses other than early detection of pregnancy —(1)Identification. A human chorionic goadotropin (HCG) test system is a device intended for any uses other than early detection of pregnancy (such as an aid in the diagnosis, prognosis, and management of treatment of persons with certain tumors or carcinomas) is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class III.(3)
Date PMA or notice of completion of a PDP is required. As of the enactment date of the amendments, May 28, 1976, an approval under section 515 of the act is required before the device described in paragraph (b)(1) may be commercially distributed. See § 862.3.