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The Instant-view-plus™ Immunochemical Fecal Occult Blood Test is a qualitative immunoassay for detection of Fecal Occult Blood. It is intended for professional and over the counter use.

This device is a Driven Flow™ chromatographic immunoassay consisting of a test strip housed in a plastic cassette.

Here's a breakdown of the acceptance criteria and study information for the Instant-view-plus™ Immunochemical Fecal Occult Blood Test, based on the provided text:

Acceptance Criteria and Reported Device Performance

The acceptance criteria are implied by the performance demonstrated in the various studies, particularly the precision/reproducibility and method comparison studies. The goal is to show substantial equivalence to predicate devices, meaning the device performs as well as or better than already approved devices.

The tables below compile the key performance metrics provided:

• Positive Percent Agreement: 100% (492/492) (99.3%, 100%)
• Negative Percent Agreement: 99% (404/408) (97.5%, 99.7%) |
  | | | Reproducibility (Lot Variability):
• Lot 1: Pos. 100%, Neg. 98.6%
• Lot 2: Pos. 100%, Neg. 97%
• Lot 3: Pos. 100%, Neg. 96.4% |
  | | | Reproducibility (Day Variability):
• Day 1: Pos. 100%, Neg. 95.1%
• Day 2: Pos. 100%, Neg. 89%
• Day 3: Pos. 100%, Neg. 98.6%
• Day 4: Pos. 100%, Neg. 95.4%
• Day 5: Pos. 100%, Neg. 96.8% |
  | | | Reproducibility (Site Variability):
• Site 1: Pos. 100%, Neg. 97.1%
• Site 2: Pos. 100%, Neg. 97.4%
• Site 3: Pos. 100%, Neg. 96.7% |
  | Assay Cut-off | Clearly defined sensitivity/specificity around cut-off | 50 ng/ml (human hemoglobin in fecal sample mixed with detection buffer).
  At 50 ng/ml: Positive % = 55%, Negative % = 45%
  At 60 ng/ml: Positive % = 100%, Negative % = 0% |
  | Method Comparison (vs. Predicate) | Acceptable Overall, Positive, and Negative Percent Agreement | Combined Sites:
• Overall Percent Agreement: 97.7% (95.2%, 99.1%)
• Positive Percent Agreement: 96.0% (90.2%, 98.9%)
• Negative Percent Agreement: 98.5% (95.6%, 99.7%) |
  | Prozone Effect | No significant prozone effect | No prozone effect observed up to 500,000 ng/mL |
  | Analytical Specificity (Hb variants) | Equivalent recognition of Hb variants | Equivalently recognizes HbA, HbS, and HbC |
  | Cross-Reactivity (Animal Hb) | No significant cross-reactivity | No significant cross-reactivity with tested animal hemoglobins (beef, chicken, fish, horse, goat, rabbit, pig, horseradish peroxidase, sheep) |
  | Interfering Substances (Vegetables) | No significant interference | No significant interference from tested vegetable extracts (broccoli, cantaloupe, cauliflower, parsnip, red radish, turnip) |
  | Interfering Supplements (Iron, Ascorbate) | No significant interference | No significant interference from iron and sodium L-ascorbate |
  | Interference from Toilet Water | No significant interference | No significant interference from samples collected in toilet water |
  | Stability (Accelerated/Real Time) | Defined shelf-life | stable for 24 months at 8-23°C |

Study Details:

2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)

• Precision/Reproducibility (Repeatability): 6 concentrations (0, 25, 50, 55, 500 ng/ml). 50 replicates per concentration (total of 300 tests per lot). Data provenance is in-house by trained laboratory professionals. This implies retrospective testing of prepared samples.
• Precision/Reproducibility (Reproducibility): 9 concentrations (0, 25, 50, 60, 60 [repeated], 500 ng/ml). 14 replicates for each sample and concentration level. Performed across three intended use sites over a minimum of 5 days. This suggests a prospective data collection design using controlled, spiked samples.
• Prozone Effect Study: 7 concentrations (1,000 to 500,000 ng/ml). 20 aliquots of each concentration. Data provenance is in-house. This is retrospective testing of prepared samples.
• Assay Cut-off Study: 7 concentrations (0, 25, 48, 50, 60, 72, 500 ng/ml). 20 aliquots of each concentration. Data provenance is in-house. This is retrospective testing of prepared samples.
• Method Comparison with Predicate Device: 299 patient samples. Performed at three POC testing sites. Data provenance is not explicitly stated beyond "patient samples" and "POC testing sites," but it implies real-world clinical samples, likely prospective or retrospective from those sites.
• Consumer Study: Concentrations were 0, 25, 50, 60, and 500 ng/ml. "Number of Samples" is consistently "20" (represented as "રત" in the table, clearly a transcription error for 20). Data provenance is in-house using spiked samples. This is retrospective testing of prepared samples.

No specific country of origin for the data is mentioned, but the manufacturer is based in Poway, California, USA, making it highly probable the studies were conducted domestically.

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)

• For the precision/reproducibility, prozone, assay cut-off, analytical specificity, cross-reactivity, and interference studies, the ground truth was established by preparing fecal samples spiked with known concentrations of human hemoglobin or other controlled substances. Therefore, no human experts were needed to establish the ground truth; it was experimentally determined.
• For the method comparison study, the "predicate test Instant-view™ Fecal Occult Blood Rapid Test" results served as the reference standard (comparative ground truth). The predicate device itself would have undergone its own validation based on established ground truth (e.g., clinical diagnosis or pathology). For this specific study, the experts are the operators at the three POC testing sites, but their qualifications are not specified beyond "two operators at each site."
• For the consumer study, similarly, no human experts established a true "ground truth." The comparison was between the new device and the predicate device on spiked samples.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set

• No explicit adjudication method (like 2+1, 3+1 consensus) is described in the provided text for any of the studies involving human interpretation.
• For studies involving spiked samples, the "truth" is the known concentration of hemoglobin or other substances, eliminating the need for adjudication.
• For the method comparison study, the readings of the Instant-view-plus™ were compared directly to the results of the predicate device, not against an expert-adjudicated ground truth.

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 involving AI assistance is mentioned. This device is a rapid immunochemical assay, not an AI-powered diagnostic imaging tool. Human interpretation is involved in reading the lines on the cassette.
• A "method comparison with predicate device" study was performed, which compared the new device's readings to those of a predicate device. This is a comparison between devices, not between human readers with and without AI assistance.
• A "consumer study" was performed, which likely involved lay users or professional users following instructions, but it was to assess the device's performance, not the improvement of human readers with AI.

6. If a standalone (i.e., algorithm only without human-in-the-loop-performance) was done

• This device is a standalone test kit that provides a visual readout (presence/absence of lines). Its performance is the algorithm's performance, as the "algorithm" is the biochemical reaction and visual indication. There isn't a separate "human-in-the-loop" vs. "standalone algorithm" distinction in the context of this immunochemical test. The studies evaluate the device's performance directly.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

• For the precision/reproducibility, prozone, assay cut-off, analytical specificity, cross-reactivity, interfering substances, and stability studies: The ground truth was experimentally determined by preparing Hb-free fecal samples spiked with known, precise concentrations of human hemoglobin, hemoglobin variants, animal hemoglobins, vegetable extracts, or other interfering substances.
• For the method comparison study: The ground truth was the result from the predicate device (Instant-view™ Fecal Occult Blood Rapid Test).
• For the consumer study: The ground truth was again the known concentration of hemoglobin in the spiked samples, used to compare the new device to the predicate.

8. The sample size for the training set

• The provided text describes studies for validation and verification of the device's performance, not the training of an algorithm. Therefore, there is no specific training set identified in the context of machine learning. The "training" for this type of device would involve development and optimization of the immunoassay components, likely using iterative testing, but this is not a formally reported "training set" in the sense of AI.

9. How the ground truth for the training set was established

• As there's no identified "training set" for an algorithm in the provided text, this question is not applicable. The device's "ground truth" during its development would have been established through controlled laboratory experiments, optimizing reagent formulations and design to achieve desired sensitivity and specificity.

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