(64 days)
The ImmunoDip™ Urinary Albumin Screen tests for the presence of elevated levels of albumin in urine. Elevated urinary albumin is also known as microalbuminuria. Elevated albumin is an early sign of possible kidney damage. Detection of elevated urinary albumin can aid in the early detection and monitoring of the course of incipient nephropathy in diabetics and hypertensive patients. For IN VITRO diagnostic use.
ImmunoDip™ Urinary Albumin Screen is an immunochromatographic test strip which is encased in a plastic housing. The ImmunoDip™ Urinary Albumin Screen is placed into a urine sample for at least three minutes and is then removed and read. Results are determined by visually comparing the relative color intensity of two blue bands to obtain a semi-quantitative result of Negative (18 mg/L).
ImmunoDip™ Urinary Albumin Screen is an immunochromatographic test strip containing monoclonal mouse antibodies against human serum albumin bound to colored latex beads. Human albumin is fixed in a band at the bottom half of the testing region. Goat anti-mouse antibodies are fixed in a band at the top half of the testing region. The dipstick is encased in an open-ended plastic housing.
When the dipstick is placed into a urine sample cup, the urine sample migrates up the test strip. Albumin present in the urine binds with blue colored latex beads present in the strip. Both beads and albumin are carried up the device by capillary action. At low levels of albumin, the great majority of blue beads are bound at the lower band containing human albumin. At higher levels of albumin, many of the beads pass through the lower band and are bound at the upper band. Levels of albumin above the decision level value of 18 mg/L will produce color on the upper band which is darker than the lower band. By observing the appearance of the two lines, the user can semi-quantitatively determine the urine microalbumin concentration as either Negative (18 mg/L).
The ImmunoDip™ Urinary Albumin Screen is an immunochromatographic test strip intended to detect elevated levels of albumin in urine (microalbuminuria), which can indicate early kidney damage in high-risk patients.
Here's a breakdown of the acceptance criteria and study information provided:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Precision: 100% agreement between operators and observers | 100% agreement obtained between two operators and two additional observers across within-day, between-day, within-run, and between-run testing (internal 20-day study with two albumin levels). |
| Accuracy (POL Users): High overall agreement with expected results over a clinically relevant range of concentrations. | 91% overall agreement with expected results (range 89%-94%) for POL users across 6 proficiency samples (4.5 mg/L, 9.0 mg/L, 15 mg/L, 22 mg/L, 36 mg/L, 72 mg/L). Exceeded 98% accuracy when 15 mg/L and 22 mg/L samples were excluded. |
| Accuracy (Trained Lab Personnel): High overall agreement with expected results. | 95% overall agreement (range 93%) for trained laboratory personnel across 6 proficiency samples. |
| Equivalence to Predicate Methods: Comparable specificity, sensitivity, and efficiency to existing urinary albumin assay methods. | Specificity: 95-97% |
| Sensitivity: 95% (against both Beckman Array and Kamiya assays) | |
| Efficiency: 95-97% |
2. Sample Size Used for the Test Set and Data Provenance
- Precision Study: The sample size for the "test set" in the precision study is not explicitly stated in terms of number of urine samples. It refers to "two levels of albumin in urine" and "all instances of within-day, between-day, within-run and between-run testing" with 100% agreement.
- POL Studies: "Six proficiency samples over a clinically relevant range of concentrations (4.5 mg/L, 9.0 mg/L, 15 mg/L, 22 mg/L, 36 mg/L and 72 mg/L)." The number of users (professional and POL users) and the number of replicates (15 replicates within-run, 5 different days between-runs, 3 POL sites between sites) contribute to the overall sample size but the exact number of unique "test set" samples is not provided.
- Clinical Studies: For comparison against predicate methods, "clinical urine samples" were used, but the specific number of these samples is not mentioned.
- Data Provenance: The document does not explicitly state the country of origin for the data. The submitter is based in Canada. The POL studies involved "Physician Office Laboratory (POL) studies" and "3 POL sites," implying real-world settings, but whether these were prospective or retrospective is not specified for all studies. The precision study was an "internal 20 day precision study."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
- Precision Study: "two operators and two additional observers" were involved in determining agreement. Their qualifications are not specified beyond "operators" and "observers."
- POL Studies: "expected results" were used as the ground truth for the 6 proficiency samples. The method or expertise used to establish these "expected results" is not detailed.
- Clinical Studies: The "ground truth" was established by two predicate quantitative methods: the Beckman Array (K922273) and the Kamiya (Crestat) Microalbumin Assay (K934146), and one semi-quantitative method, the DCLare™ ImmunoDip™ Stick for Microalbuminuria (K972337).
4. Adjudication Method for the Test Set
- The document does not describe an explicit adjudication method (e.g., 2+1, 3+1).
- In the precision study, 100% agreement was obtained between "two operators and two additional observers," implying direct consensus or agreement without needing a tie-breaker.
- For the POL and clinical studies, the results were compared against an "expected result" or predicate device results, not against a human adjudicated consensus derived from multiple readers of the ImmunoDip device itself.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- A formal MRMC comparative effectiveness study, as typically understood in the context of comparing human readers with and without AI assistance, was not conducted.
- The studies involved comparing the ImmunoDip device's performance by "POL users" versus "trained laboratory personnel" and against established "predicate methods." There is no mention of an "AI assistance" component or an effect size for human readers improving with AI.
6. Standalone (Algorithm Only) Performance
- The ImmunoDip™ Urinary Albumin Screen is a visual immunochromatographic test strip read by a human. Therefore, a standalone "algorithm only" performance study in the sense of a fully automated AI system without human interaction was not conducted, as the device itself is not a software algorithm. Its performance is the "standalone" performance based on visual interpretation.
7. Type of Ground Truth Used
- Precision Study: The ground truth was based on the consensus ("100% agreement") among two operators and two observers for known albumin levels (two levels specified).
- POL Studies: The ground truth for the proficiency samples was "expected results," which implies they were pre-determined values for the proficiency samples. The method of determination for these "expected results" is not specified but would typically come from a reference method or certified values.
- Clinical Studies: The ground truth was established by two full quantitative predicate methods (Beckman Array, Kamiya Microalbumin Assay) and one semi-quantitative predicate method (DCLare™ ImmunoDip™ Stick for Microalbuminuria).
8. Sample Size for the Training Set
- The document implies that the device is a test strip read visually by a human, not a machine learning or AI algorithm that requires a "training set" in the typical sense. Therefore, the concept of a "training set" as it relates to AI development is not applicable here. The studies described are for validation of the chemical-biological test strip and human interpretation.
9. How the Ground Truth for the Training Set Was Established
- As the device is not an AI algorithm requiring a training set, this question is not applicable.
§ 862.1645 Urinary protein or albumin (nonquantitative) test system.
(a)
Identification. A urinary protein or albumin (nonquantitative) test system is a device intended to identify proteins or albumin in urine. Identification of urinary protein or albumin (nonquantitative) is used in the diagnosis and treatment of disease conditions such as renal or heart diseases or thyroid disorders, which are characterized by proteinuria or albuminuria.(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.