(88 days)
SPOROX® Test Strips provide a rapid, convenient, semi-quantitative means of indicating whether effective concentrations of hydrogen peroxide are present in SPOROX™ Sterilizing and Disinfecting Solution. The SPOROX® Test Strips indicate concentrations of hydrogen peroxide but do not confirm disinfection or sterilization.
The SPOROX™ Test Strips consist of a 0.2 x 0.2 inch reagentcontaining pad attached to one end of a 0.2 x 3.25 inch polystyrene handle. The reagent pad is immersed in the sample. The strip is rotated to a vertical position for five seconds with the pad up to allow excess sample to drain by gravity and then is covered with a chamber to prevent sample evaporation. The reagent pad is observed 15 minutes after immersion. If the pad is completely brown/black, the SPOROX™ Sterilizing and Disinfecting Solution contains hydrogen peroxide at concentrations greater than 6.0% (the minimum effective concentration or MEC). If the SPOROX® Sterilizing and Disinfecting Solution contains hydrogen peroxide at concentrations of 6.0% or less, a distinct white area forms in the center of the pad. The reagent pad contains iodide and starch plus a reducing compound that prevents visible reaction when the hydrogen peroxide concentration is at or below the MEC. When the peroxide level is in sufficient excess of the MEC, the surplus oxidizes the iodide to iodine which in turn forms a dark-colored complex with the starch.
Here's an analysis of the provided text regarding the SPOROX® Test Strips, focusing on the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Stated or Implied) | Reported Device Performance |
|---|---|
| Specificity: No false PASS results at hydrogen peroxide concentrations at or below the Minimum Effective Concentration (MEC) of 6.0%. (Implied: 100% specificity at 6.05% H2O2 as a critical threshold implying below 6.0% should also be 100% specific) | At 6.05% hydrogen peroxide, 0 out of 168 results were PASS, giving a test specificity (lack of false PASS results) of 1.00 (100%). This confirms that at concentrations just above the MEC threshold, the device correctly indicates a failure to pass (i.e. not effective concentration), which fulfills the requirement of not giving false PASS results when the concentration is at or below 6.0%. |
| Sensitivity/Accuracy for Effective Concentrations: Ability to indicate "PASS" when hydrogen peroxide concentration is effectively above the MEC (e.g., 6.58% and 7.00%). | At 6.58% hydrogen peroxide, 41 out of 84 results were PASS (48.8%). |
| At 7.00% hydrogen peroxide, 165 out of 168 results were PASS (98.2%). | |
| Mechanism of Indication: Distinct white area forms in the center of the pad when hydrogen peroxide concentration is 6.0% or less. | "If the SPOROX® Sterilizing and Disinfecting Solution contains hydrogen peroxide at concentrations of 6.0% or less, a distinct white area forms in the center of the pad." The study implicitly validates this by demonstrating 0 PASS results at 6.05%, suggesting correct visual indication of "FAIL" (white area). |
| Mechanism of Indication: Pad is completely brown/black when hydrogen peroxide concentration is greater than 6.0%. | "If the pad is completely brown/black, the SPOROX™ Sterilizing and Disinfecting Solution contains hydrogen peroxide at concentrations greater than 6.0%." The study implicitly validates this by the high rate of "PASS" (brown/black) results at 7.00%. |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size:
- For 6.05% hydrogen peroxide: 168 results
- For 6.58% hydrogen peroxide: 84 results
- For 7.00% hydrogen peroxide: 168 results
- Total individual tests/readings: 168 + 84 + 168 = 420 results.
- The study used SPOROX™ Test Strips from three trial production lots.
- Data Provenance: The document does not explicitly state the country of origin. It describes a "blind study" involving "seven participants" testing "SPOROX™ standards assayed by a titrimetric procedure." This suggests a controlled laboratory setting, likely in the US where Serim Research Corporation is based. The study is prospective in the sense that the experiment was designed and executed to test the performance of the strips under controlled conditions.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Ground Truth Establishment: The ground truth was established by "SPOROX™ standards assayed by a titrimetric procedure." This is an objective chemical assay/measurement.
- Number of Experts: Zero experts were used to establish the ground truth for the test set, as it was based on a direct chemical measurement (titrimetric procedure) rather than expert opinion.
- Qualifications of Experts: Not applicable, as expert consensus was not the ground truth method.
4. Adjudication Method for the Test Set
- Adjudication Method: The document does not describe an adjudication method for the test set in the traditional sense of resolving discrepancies between multiple human readers. Instead, the study involved "seven participants in blind studies" using the test strips and reporting their results against the known concentrations (ground truth) established by the titrimetric procedure. It implies individual participants' readings were compared directly to the titrimetric ground truth. There is no mention of a process to adjudicate disagreements among the seven participants if they read the same strip differently (though this is less likely for a clear pass/fail strip).
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
- MRMC Study: No, a formal MRMC comparative effectiveness study as typically understood in medical imaging (comparing AI-assisted human readers to non-AI-assisted human readers) was not performed.
- Effect Size: Not applicable, as no MRMC study was conducted. The study evaluated the performance of the device itself, not the impact of AI assistance on human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Standalone Performance: Yes, in a way. The device (SPOROX® Test Strip) is the "algorithm" in this context. Its "performance" is its ability to chemically react and display a visual result (brown/black or white spot) based on the hydrogen peroxide concentration. The "seven participants" are effectively the "readers" of this visual output. The study measures the accuracy of this device's visual output against a known chemical standard. While humans interpret the final visual output, the core performance being evaluated is the chemical reaction and visual change of the strip itself, independent of complex human interpretation or AI.
7. The Type of Ground Truth Used
- Type of Ground Truth: The ground truth used was "SPOROX™ standards assayed by a titrimetric procedure." This represents an objective chemical measurement or reference standard.
8. The Sample Size for the Training Set
- Training Set Sample Size: The document does not explicitly mention a separate "training set" or a sample size for one. The study described appears to be a verification/validation study used to demonstrate the device's performance, not a study involving iterative training of an algorithm.
9. How the Ground Truth for the Training Set Was Established
- Ground Truth for Training Set: Not applicable, as no separate training set or associated ground truth establishment process is described. The device operates based on a fundamental chemical reaction, not a machine learning algorithm requiring a separate training phase with labeled data in the context of this submission.
§ 880.2800 Sterilization process indicator.
(a)
Biological sterilization process indicator —(1)Identification. A biological sterilization process indicator is a device intended for use by a health care provider to accompany products being sterilized through a sterilization procedure and to monitor adequacy of sterilization. The device consists of a known number of microorganisms, of known resistance to the mode of sterilization, in or on a carrier and enclosed in a protective package. Subsequent growth or failure of the microorganisms to grow under suitable conditions indicates the adequacy of sterilization.(2)
Classification. Class II (performance standards).(b)
Physical/chemical sterilization process indicator —(1)Identification. A physical/chemical sterilization process indicator is a device intended for use by a health care provider to accompany products being sterilized through a sterilization procedure and to monitor one or more parameters of the sterilization process. The adequacy of the sterilization conditions as measured by these parameters is indicated by a visible change in the device.(2)
Classification. Class II (performance standards).