(458 days)
ProSpore2 is a biological sterilization process indicator for EtO (Ethylene Oxide) sterilization. This device is intended for use by a health care provider to accompany products being sterilized through an EtO sterilization procedure and to monitor the adequacy of sterilization. The testing and validations referred to in this document were done using a 10/90 Ethylene Oxide mixture at 600 mg/L, 54°C, and with a relative humidity between 30% and 80%.
ProSpore2 is a self-contained biological indicator used for determining the efficacy of an Ethylene Oxide sterilization cycle. ProSpore2 is comprised of a plastic tube housing with a plastic cap. Inside of the tube is a 1.2 - 1.5 ml glass ampoule of growth media consisting of Tryptic Soy Broth (soybean casein digest) and a pH indicator - bromothymol blue. Also inside of the tube housing is a paper spore disc impregnated with a population of 106 Bacillus subtilis spores (ATCC #9372).
The provided document describes the "PROSPORE 2ª SELF CONTAINED BIOLOGICAL VII. INDICATOR" for Ethylene Oxide sterilization. It details the device, its operational principles, and a summary of testing conducted to demonstrate its substantial equivalence to a legally marketed predicate device.
Here's the breakdown of the acceptance criteria and study information, addressing your points:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state pre-defined acceptance criteria in a quantitative manner as one might find in a clinical study. Instead, it focuses on demonstrating "stability" and "effectiveness" in comparison to a predicate device. The performance is summarized as meeting these qualitative criteria.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Shelf life stability (18 months) | Demonstrated D-value stability and Population stability with three separate lots. |
| Recovery media efficacy | Demonstrated consistent recovery of "low numbers" of "injured spores." |
| Incubation period | Achieved recovery and color change within a 48-hour incubation period. |
| Stability of color change | Color change (green to yellow) was stable and effectively indicated growth. |
| Overall effectiveness in monitoring EtO cycles | Demonstrated effectiveness in routine Ethylene Oxide sterilization cycles. |
| Substantial equivalence to predicate device (Attest™) | ProSpore2® is "substantially equivalent in composition and function" based on the testing results. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The document states that "three separate lots of finished product ProSpore2 vials" were used for shelf-life stability testing. It doesn't specify the exact number of units per lot or the total number of units tested across various experiments (e.g., recovery media efficacy, 48-hr incubation).
- Data Provenance: The data appears to be prospective as it involves the testing of the newly developed ProSpore2® device by the manufacturer (Raven Biological Laboratories, Inc.) for the purpose of regulatory submission. The country of origin for the data is implied to be the United States, where the manufacturer is located and where the FDA regulatory process took place.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This type of information is not detailed in the provided summary. Biological indicator testing typically relies on standardized laboratory procedures and measurements (e.g., spore enumeration, D-value calculation, growth observation) rather than expert consensus on subjective interpretations. Therefore, the "ground truth" is established by the inherent biological response and observable color change, not by expert interpretation.
4. Adjudication Method for the Test Set
This information is not detailed in the provided summary. Given the nature of biological indicator testing, adjudication by multiple human experts is typically not a primary method for determining the success or failure of the indicator itself. The outcome (color change or no color change) is a direct, objective result of spore viability.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is more common for imaging diagnostics or other AI-assisted diagnostic tools where human readers interpret complex data with and without AI assistance. The ProSpore2® is a self-contained biological indicator, and its performance is assessed directly through its biological response and observable color change, not through human interpretation that would be improved by AI.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
This concept is not applicable to the ProSpore2® device. The device itself is the "standalone" indicator. There is no AI algorithm being used, nor is there a human-in-the-loop interacting with an algorithm. The performance of the device is assessed by observers noting the color change (or lack thereof) after incubation.
7. Type of Ground Truth Used
The ground truth used is primarily biological response and physical observation. For spore viability, this involves:
- Biological viability: The ability of Bacillus subtilis spores to germinate and grow when not sufficiently sterilized, leading to metabolic activity.
- pH change: The metabolic activity of viable spores produces acidic byproducts, causing a quantifiable pH drop in the growth media.
- Colorimetric change: The pH indicator (bromothymol blue) visibly changes color from green to yellow in response to the pH drop, indicating viable spore growth.
This is a direct, objective measurement of the indicator's function.
8. Sample Size for the Training Set
This information is not applicable/not provided. The ProSpore2® is a physical biological indicator, not an AI model or algorithm that requires a "training set" in the computational sense. The device's design and formulation were developed through traditional biological and chemical engineering, not machine learning.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable/not provided for the same reasons as point 8. The "ground truth" for developing such a device would involve extensive laboratory research, microbiology, and chemical principles to ensure the correct spore type, population, growth media, and indicator system are effectively integrated. This is a scientific and engineering development process, not the establishment of ground truth for a machine learning training set.
§ 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).