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510(k) Data Aggregation
(166 days)
HemaPrompt Gastric is a guaiac-based in-vitro method for the qualitative detection of occult blood in gastric aspirate or vomitus by medical professionals only. A separate segment of pH paper is provided on the slide for estimation of pH of the gastric juice.
It is used for the early detection of occult blood in such conditions as gastric trauma, gastric or duodenal ulceration, gastric cancer, esophageal varices, situations of exogenous or endogenous gastritis, leukemia, and hereditary telangiectasia. These conditions may be encountered in the emergency room, recovery room or intensive care.
The HemaPrompt Gastric slide, used with a buffered developer and a buffered guaiac paper, is a guaiac based test for the detection of occult blood in gastric samples. The test is not affected by low pH, and is free from interferences by normal therapeutic concentrations of iron, ranitidine, and antacids. A separate area is provided to test for the pH of the specimen.
When a gastric specimen containing blood is applied to the HemaPrompt Gastric test paper, hemoglobin from the lysed blood cells in the sample comes in contact with the guaiac in the paper. The developer, a buffered solution of alcohol and hydrogen peroxide, which is applied with two drops to the guaiac on the slide, creates a peroxidase-like reaction in the presence of hemoglobin which in turn causes a blue coloration in the test paper. This test will turn blue in the presence of more than 100 mcg Hb/ ml gastric juice.
The HemaPrompt Gastric device detects occult blood in gastric samples. The provided information details several studies to assess its performance.
1. Acceptance Criteria and Reported Device Performance:
The document implies an acceptance criterion for sensitivity at 100 mcg Hb/ml gastric juice.
| Acceptance Criteria | Reported Device Performance | Study |
|---|---|---|
| Positive reaction at > 100 mcg Hb/ml gastric juice | 100% positive reaction at 200 mcg Hb/ml or greater | Patient Gastric Samples, Intubated Volunteer Samples, PBS Samples |
| Positive reaction at > 100 mcg Hb/ml gastric juice | 81.25% positive reaction at 100 mcg/ml (PBS samples) | PBS Samples |
| Not affected by low pH | Tested across pH 1.0 to 7.0 (via PBS samples) | PBS Samples |
| Not affected by normal therapeutic concentrations of iron, ranitidine, and antacids | Concentrations of ranitidine, ferrous sulfate, and an antacid (Mylanta) did not alter results | PBS Samples |
| Excellent reproducibility above 100 mcg/ml gastric juice | Excellent reproducibility demonstrated over a two-week period, with samples stored up to 10 days at 5% | Reproducibility study (not explicitly named or detailed) |
| Monitors react as expected | All monitors reacted in the expected manner (+ve turned blue and the "negative" monitor remained non-reactive) | Monitor reaction study (not explicitly named or detailed) |
2. Sample Sizes and Data Provenance:
- Test Set:
- Patient Gastric Samples: 12 samples (retrospective/clinical, origin not specified, but implies a clinical setting).
- Healthy Volunteer Gastric Samples: 8 samples obtained by intubation (prospective, volunteer, origin not specified).
- Synthetic Gastric Juice (PBS): Not explicitly stated how many distinct PBS samples were used, but they were subjected to titration for pH (1.0 to 7.0) and spiked with hemoglobin (50, 100, 200, 500 mcg/ml). This implies a controlled laboratory setting.
3. Number of Experts and Qualifications:
Not applicable. The assays are chemical reactions, and the results are read by observing a color change. The document does not mention any expert interpretation for establishing ground truth for the device's performance.
4. Adjudication Method:
Not applicable. The tests are based on chemical reactions resulting in a visual color change. There is no mention of human interpretation requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No. This is a qualitative chemical test, not an imaging or diagnostic algorithm requiring human interpretation and a multi-reader study.
6. Standalone Performance:
Yes, the studies described are standalone performance evaluations of the HemaPrompt Gastric device. The document explicitly describes the device's reaction to various hemoglobin concentrations and conditions.
7. Type of Ground Truth Used:
The ground truth for the test set was established by:
- Known Hemoglobin Concentrations: For the patient samples and healthy volunteer samples, known concentrations of hemoglobin were added to the samples. For the PBS samples, known concentrations of hemoglobin were titrated into the solutions. This represents a ground truth based on spiking with known analytes/concentrations.
- Clinical observation: The initial positive results in intubated volunteer samples (37.5% with no added blood) imply that some intrinsic bleeding occurred due to the intubation procedure itself, which would be considered a clinical ground truth for the presence of blood, though not quantified.
8. Sample Size for Training Set:
Not applicable. This device is a chemical test, not a machine learning algorithm that requires a training set.
9. How Ground Truth for Training Set Was Established:
Not applicable, as there is no training set for this type of device.
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(132 days)
HemaPrompt is a guaiac-based in-vitro slide method for the qualitative detection of occult blood in feces by lay persons.
It is a useful aid in the diagnosis or early detection of a number of gastrointestinal disorders, and is recommended for use in monitoring for recurrences of previously treated bowel conditions, and in screening for colorectal cancer or for other sources of gastro-intestinal bleeding.
For Over-The-Counter Use
HemaPrompt is presently approved and being used by health care professionals for the screening of stool for occult blood. It is a guaiac based system using a color change in the test slide to show the presence of a pathological amount of blood in the stool, which indicates the need for further investigation by medical personnel.
HemaPrompt for use at home is the same in configuration and chemical constitution as that currently used by professionals. HemaPrompt is much simpler and safer to use than similar home-use kits because the developing solution is individually contained in each slide thereby obviating the need to measure or handle a potentially hazardous solution. This design also obviates variations in user technique, and because of a "built - in" control monitor, proper function is obvious.
HemaPrompt Device Performance Study Summary
1. Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| User Interpretation Accuracy: No statistically significant variation in test interpretation between lay persons and healthcare professionals. | Observation: A study involving 250 lay persons and 50 nurses showed no statistically significant variation in their ability to perform the test and interpret results. |
| Understandability of Instructions: High understandability rate for critical safety instructions (e.g., "Should you see a physician if your test is positive?"). | Observation: A questionnaire given to 50 lay persons demonstrated a greater than 95% understandability rate for the most important question regarding physician consultation after a positive test. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size:
- Lay persons for interpretation study: 250 individuals
- Nurses for interpretation study: 50 individuals
- Lay persons for instruction understandability: 50 individuals
- Data Provenance: The document does not explicitly state the country of origin. However, given it's a 510(k) submission to the FDA, it can be inferred that the studies were conducted in the US. The studies appear to be prospective as participants were "asked... to perform the test and interpret the results" or given a questionnaire.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The study described focuses on user comprehension and interpretation of the device, rather than the device's diagnostic accuracy against a clinical ground truth. Therefore, the concept of "experts establishing ground truth" for the test results performed by the participants is not directly applicable in the conventional sense. The "ground truth" for the interpretation study was likely the manufacturer's intended correct interpretation of the HemaPrompt test (positive/negative), which the nurses were presumed to already understand.
- Experts for interpretation comparison: 50 nurses who routinely perform fecal occult blood tests in a hospital. Their qualifications are implied by their routine professional experience.
- Experts for instruction revision (implicitly): The "manufacturer" or "experts" involved in revising the instructions based on lay person feedback. No specific number or qualifications are provided.
4. Adjudication Method for the Test Set
The document does not describe an explicit adjudication method (like 2+1 or 3+1). For the interpretation study, the comparison was between the interpretations of lay persons and nurses. The "ground truth" for each specific test read by the participants would be the actual result shown on the HemaPrompt slide (positive/negative), which was then compared to their interpretation. It's not a consensus-based adjudication but rather a direct comparison of individual interpretations against a known expected outcome.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a MRMC comparative effectiveness study involving human readers with and without AI assistance was not mentioned. The device is a diagnostic test itself, not an AI-powered diagnostic aid for human readers.
6. Standalone Performance Study (Algorithm Only Without Human-in-the-loop Performance)
Yes, the HemaPrompt device itself has a standalone performance, albeit implicitly. The submission states that "HemaPrompt for use at home is the same in configuration and chemical constitution as that currently used by professionals." This implies that the chemical reaction and color change (the "algorithm" in this context) of the device functions independently, and its performance (false positive/negative rates) are "no different from the professionally used test." The study then focuses on the user's ability to operate and interpret this standalone device.
7. Type of Ground Truth Used
- For user interpretation accuracy: The ground truth for the study participants' interpretations would be the actual positive or negative result displayed by the HemaPrompt slide for the test specimens they were provided. This is an objective chemical reaction result.
- For the device's clinical efficacy (implied): The text mentions the clinical benefits of early detection and states there is a "recognized false positive and false negative rate which is no different from the professionally used test." This suggests that the ground truth for the device's diagnostic performance implicitly relies on established clinical outcomes and pathology. However, the study described in the 510(k) focuses on user performance, not direct diagnostic accuracy via pathology comparison.
8. Sample Size for the Training Set
The document does not describe a "training set" in the context of an algorithm or AI model. The studies described are for user performance and instruction comprehension.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no "training set" for an algorithm described in this submission. For the user studies, the "training" for the lay persons involved reading the provided instructions.
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(88 days)
HemaPrompt is a gualac-based in-vilro slide method for the qualitative detection of occult blood in feces and gastric aspirate or vomitus by medical professionals only.
For fecal testing, it is a useful ald In the diagnosis of a number of gastrointestinal disorders, and is recommended for use in 1) routine physical examinations 2) routine hospital testing 3) screening for colorectal cancer or gastro-Intestinal bleeding from any other source.
For the testing of gastric contents it is used for the early detection of occult blood in conditions such as gastric trauma, gastric or duodenal ulceration, gastric cancer, esophageal varices, situations of likely exogenous or endogenous gastrills, leukemia, and hereditary telangiectasia. These conditions may be encountered in the emergency room, recovery room or intensive care.
The HemaPrompt slide, used with a buffered developer, is a guaiac based test for the detection of occult blood in both gastric and fecal samples. The test is not affected by low pH. When used with gastric specimens, it is free from interferences by normal therapeutic concentrations of iron, ranitidine, cimetidine and antacids.
When a gastric or fecal specimen containing blood is applied to the HemaPrompt test paper, hemoglobin from the lysed blood cells in the sample comes in contact with the guaiac in the paper. The developer, a buffered solution of alcohol and hydrogen peroxide, is applied by pulling the tab on the slide and creates a guaiac / peroxidase-like reaction in the presence of hemoglobin which in turn causes a blue coloration in the test paper. This test will turn blue in the presence of more than 2 mg Hb/ G stool and more than 200 mcg Hb/ ml gastric juice
Here's a breakdown of the acceptance criteria and study information for HemaPrompt, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria (Detection Limit) | Reported Device Performance (Fecal) | Reported Device Performance (Gastric) |
|---|---|---|
| Fecal: > 2 mg Hb/G stool | Reliably and definitely reacted at >= 2 mg Hb/G of stool within 60 seconds. | N/A |
| Gastric: > 200 mcg Hb/ml gastric juice | N/A | Reliably and definitely reacted at >= 200 mcg Hb/ml gastric juice within 60 seconds (for concentrations of 200 mcg/ml and greater, 100% positive reactions were observed). |
| Fecal: False Positive Rate for controlled diet |
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