(133 days)
EGENS Pregnancy Test Midstream I is intended for the qualitative detection of human chorionic gonadotropin (hCG) in urine, as an aid in early detection of pregnancy, in some cases as early as five (5) days before the expected period, i.e., as early as six (6) days before the day of the missed period.
EGENS Pregnancy Test Midstream II is intended for the qualitative detection of human chorionic gonadotropin (hCG) in urine, as an aid in early detection of pregnancy, in some cases as early as five (5) days before the expected period, i.e., as early as six (6) days before the day of the missed period.
EGENS Pregnancy Test Midstream I and EGENS Pregnancy Test Midstream II are used for in vitro qualitative detection of Human Chorionic Gonadotropin (HCG) in human urine, and are designed to be tested in dip or midstream mode. The test device consists of a single test strip assembled in a plastic housing, with an absorbent tip. The only difference between EGENS Pregnancy Test Midstream I and EGENS Pregnancy Test Midstream II is the plastic casing. The device is in a ready-to-use format.
Here's an analysis of the acceptance criteria and study details for the EGENS Pregnancy Test Midstream I and II, based on the provided text:
EGENS Pregnancy Test Midstream I and II: Acceptance Criteria and Supporting Study
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state formal "acceptance criteria" with numerical thresholds for performance metrics. Instead, it demonstrates the device's analytical and clinical performance through various studies. The key performance characteristics are compared against the predicate device and established expectations for pregnancy tests.
| Performance Characteristic | Acceptance Criteria (Implied/Expected) | Reported Device Performance (EGENS Pregnancy Test Midstream I & II) |
|---|---|---|
| Analytical Sensitivity | 10 mIU/mL (matches predicate) | Both devices demonstrated a sensitivity of 10 mIU/mL (100% positive detection at 10 mIU/mL, with decreasing positive rates at lower concentrations). |
| Hook Effect | No hook effect up to high hCG concentrations. | No hook effect observed at hCG concentrations up to 500,000 mIU/mL. |
| Specificity (Non-pregnant females) | No false positive results. | No false positive results were observed in 300 urine samples from healthy, non-pregnant females across pre-menopausal, peri-menopausal, and post-menopausal groups. |
| Cross-Reactivity | No cross-reactivity with hLH, hFSH, hTSH. | No cross-reactivity observed with 500 mIU/mL hLH, 1000 mIU/mL hFSH, and 1000 µIU/mL hTSH at tested concentrations. Performance not affected by hCG ß-core fragment up to 500,000 pmol/L. |
| Interfering Substances | No interference from common substances and physiological variations (pH, density). | No interference observed from a wide range of common substances (Acetaminophen, Aspirin, Ascorbic acid, Caffeine, Hemoglobin, etc.) at specified concentrations. Performance not affected by urine pH between 4 and 9 or urine density between 1.000 and 1.035. |
| Method Comparison (Conformity with Predicate) | High conformity (e.g., 100% agreement) with the predicate device. | 100% conformity between the candidate device and the predicate device in a study of 206 "real" urine samples and an additional 100 urine samples tested by both devices. |
| Lay Person Study Agreement with Professional Results | High agreement with professional results. | 100% positive and 100% negative conformity with professional results from 206 individual pregnancy tests. High percent agreement (98-100%) was also shown for spiked urine samples (5mIU/ml, 6.5mIU/ml, 8.0mIU/ml, 10mIU/ml hCG) when tested by lay users. |
| Early Pregnancy Detection | Early detection of pregnancy, e.g., five days before expected period, consistently. | Detected 68% positive hCG five days before the Expected Menstrual Period (EMP) (69% in the summary table), and 100% positive hCG on the day of EMP. This generally aligns with "some cases as early as five (5) days before the expected period". |
| Ease of Use (Lay Person) | Consumers find the test easy to use and understand labeling. | Questionnaire results reflected that consumers found the test easy to use and did not have trouble understanding the labeling and interpreting the results. |
| Reproducibility | Consistent results across lots and operators. | Both devices exhibited reproducible results across three device lots and three different operators for analytical sensitivity testing. |
2. Sample Size Used for the Test Set and Data Provenance
- Analytical Performance (Precision/Sensitivity):
- Sample Size: For each hCG concentration (0, 2.5, 5, 6.5, 8, 9, 10, 15, 25, 50 mIU/mL), 5 replicates were tested per day for 5 days for each of 3 device lots. This totals 5 (replicates) * 5 (days) * 3 (lots) = 75 tests per hCG concentration. With 10 concentrations, this is 750 tests per device type (Midstream I or II). The combined data for both dip and midstream methods suggests 150 total results per concentration from the 3 lots (50 per lot).
- Data Provenance: Negative female urine spiked with WHO-traceable hCG standard. This is laboratory-controlled, prospective data. The country of origin of the urine samples is not explicitly stated but presumably from the manufacturer's location or a related lab.
- Hook Effect Test:
- Sample Size: Not explicitly stated, but negative urine samples were spiked with 7 varying hCG concentrations. "All tested concentrations gave a positive result." This implies each concentration was tested at least once, and likely in replicates to confirm.
- Data Provenance: Laboratory-controlled, prospective data using spiked negative urine samples.
- Specificity and Cross-Reactivity:
- Specificity (Non-pregnant females): 300 urine samples.
- Cross-Reactivity (hLH, hFSH, hTSH, hCG ß-core fragment): 30 replicates per test (negative and positive urine samples spiked with cross-reactants) using three device lots. This means 30 * 3 = 90 tests per cross-reactant condition.
- Data Provenance: Prospective collection of urine samples and laboratory-controlled spiking for cross-reactivity. The "300 urine samples" for specificity were "collected from healthy, nonpregnant female in pre-menopausal (ages 18
40 years old), peri-menopausal (4155 years old) and post-menopausal (>55 years old) groups. 100 people for each age group."
- Interfering Substance Study:
- Sample Size: Urine samples containing 0, 5, and 10 mIU/mL hCG were spiked with "the interfering substance to obtain the certain desired test concentration." The number of replicates is not specified for each substance, but implies testing was sufficient to determine no effect.
- Data Provenance: Laboratory-controlled, prospective data using spiked urine samples.
- Method Comparison Study (with Predicate Device):
- Sample Size:
- 206 urine samples initially: 100 for Midstream I, 106 for Midstream II.
- Additional 100 urine samples tested by both Midstream I and Midstream II, and both in-stream and dip methods, yielding 200 results for each device.
- Total urine samples used for method comparison involving "real" samples: 206 + 100 = 306 unique samples.
- Data Provenance: Prospective collection of urine samples from women presenting to test for pregnancy. This represents clinical, prospective data.
- Sample Size:
- Lay Person Study:
- Sample Size (Clinical Samples): 306 women's individual urine samples. 200 for Midstream I, 106 for Midstream II.
- Sample Size (Spiked Samples): 400 spiked urine samples (100 samples each for 5, 6.5, 8, 10 mIU/mL hCG) were tested by 200 lay persons.
- Data Provenance: Prospective collection of urine samples and clinical prospective testing by lay users, with concurrent professional testing as ground truth. (Spiked samples were laboratory-controlled, prospective).
- Early Pregnancy Test Study:
- Sample Size: 585 urine samples collected from 65 pregnant women (65 characterized cycle segments of conceptive cycles).
- Data Provenance: Prospective collection of samples from pregnant women. This is clinical, prospective data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- General Ground Truth for Clinical Samples: For the "professional testing" mentioned in the Lay Person Study and the "Method Comparison Study," the ground truth was presumably established by a laboratory assay (e.g., quantitative hCG measurement) or by the predicate device's results. The document refers to "professional results" and "predicate device" as the comparators.
- Qualifications of Experts: The document does not specify the number or qualifications of "experts" (e.g., laboratory technicians, clinical professionals) who interpreted the ground truth results for clinical studies. For the "professional testing" in the lay person study, it's implied clinical laboratory personnel.
4. Adjudication Method for the Test Set
The document does not explicitly describe an adjudication method like 2+1 or 3+1. For quantitative results (like hCG levels used for spiking or professional ground truth), there wouldn't typically be adjudication in the same way as for human interpretation of images. For the method comparison and lay person studies, the "professional result" or "predicate device" served as the established outcome against which the new device was compared. Discrepancies, if any, would likely be analyzed, but a formal adjudication process (i.e., multiple readers resolving disagreements) is not mentioned.
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
- No MRMC Comparative Effectiveness Study: This is not an AI-assisted device, but rather a lateral flow immunoassay (pregnancy test). Therefore, an MRMC comparative effectiveness study involving human readers improving with AI assistance is not applicable to this device. The "readers" are the lay users or professionals interpreting the test result line.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Algorithm Only Not Applicable: This is a diagnostic test where the user interprets a visual result (line appearing). There is no "algorithm" in the sense of a software-based diagnostic tool that operates without human intervention. The device's performance is inherently "standalone" in that it provides a result without additional computational input, but it still requires human visual interpretation.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
- Analytical Studies (Sensitivity, Hook Effect, Cross-Reactivity, Interfering Substances): Ground truth was established by spiking known concentrations of hCG or interfering substances into negative urine samples, traceable to WHO International Standard.
- Specificity Study (Non-pregnant females): Ground truth was established by clinical assessment (healthy, non-pregnant status of donors) and presumably confirmation of negative hCG status by a laboratory method.
- Method Comparison Study: Ground truth was the result of the legally marketed predicate device (Wondfo One Step HCG Urine Pregnancy Test Strip, Cassette, Midstream).
- Lay Person Study: Ground truth was professional testing results (presumably a laboratory hCG assay or the predicate device).
- Early Pregnancy Test Study: Ground truth was based on characterized cycle segments of conceptive cycles from pregnant women, meaning the women were confirmed pregnant and samples were collected relative to their Expected Menstrual Period (EMP). This is a form of clinical outcomes data coupled with the expected physiological presence of hCG.
8. The Sample Size for the Training Set
- No Explicit Training Set: Lateral flow immunoassays like this device typically do not have a "training set" in the machine learning sense. The device's performance is based on its chemical and biological components (antibodies, membrane, etc.) which are developed and optimized through R&D. The studies described are for validation and characterization of the finished device's performance, not "training."
9. How the Ground Truth for the Training Set was Established
- As there is no explicit "training set" in the context of machine learning for this device, this question is not applicable. The device's operational characteristics (e.g., antibody binding, flow dynamics) are established through a traditional scientific and engineering development process, not a data-driven training regimen.
§ 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.