(149 days)
The qke Steam SCBI 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 nominal 100,000 spores of Geobacillus stearothermophilus on a carier and enclosed in a protective plastic vial. The spores have a known resistance to certain steam sterilization cycles. The device can be used for gravity and pre-vacuum cycles according to the following conditions: 121 °C, 30 minutes / 132, 134 and 135°C, 3 minutes.
Subsequent growth or failure of the microorqanisms after an incubation time of 24 hours at 55-60 °C indicates the adequacy of sterilization.
The gke Steri-Record Steam Mini-Bio-Plus SCBI uses a plastic vial with a minimized internal volume containing a biological indicator spore disc and a glass ampoule with a growth medium and pH-indicator inside. The growth medium is optimized to support growth.
Here's a breakdown of the acceptance criteria and study information for the Gke Steri-Record Steam Mini-Bio-Plus Self-Contained Biological Indicator (SCBI) based on the provided text:
Gke Steri-Record Steam Mini-Bio-Plus SCBI Acceptance Criteria and Performance Study
The Gke Steri-Record Steam Mini-Bio-Plus SCBI is intended to monitor the adequacy of steam sterilization procedures. Its performance was evaluated against recognized standards for biological indicators.
1. Table of Acceptance Criteria and Reported Device Performance
| Test | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Total Viable Spore Count | ≥10^5^/unit per ISO 11138-3 | Passed |
| D value (at 121°C) | ≥1.5 min. at 121°C per ISO 11138-3 | Passed |
| z-value | ≥6°C per ISO 11138-3 | Passed |
| Survival time (at 121°C) | ≥4.5 min. per ISO 11138-3 | Passed |
| Kill time (at 121°C) | ≥13.5 min. per ISO 11138-3 | Passed |
| Carrier & Primary Packaging Evaluation | No inhibitory properties on the growth of gke Steam SCBI after exposure to steam sterilization processes (ISO 11138-1:2006, 5.2 and Annex B) | Passed |
| Holding Time Assessment | No negative impact on the growth of SCBIs after ≤ 72 h holding time. | Passed |
| Reduced Incubation Time Studies | 30 – 80% of BIs survived in all tested partial cycles. No further growth of BIs after 24 hours of incubation is observed. | Passed |
| Medium Suitability | USP medium suitability for Self-Contained Biological Indicators (SCBIs) | Passed |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the specific numerical sample sizes for each test in the "test set" (i.e., the BIs used for performance evaluation). However, it mentions that testing was performed “using multiple lots of gke Steri-Record Steam Mini-Bio-Plus self-contained biological indicators over the range of the shelf life.” This implies a statistically significant number of BIs were used to ensure representativeness.
Data Provenance: The studies were conducted by GKE-GMBH, a German company (Waldems, Germany), indicating the country of origin of the data. The studies are described as internal performance testing to support a 510(k) submission, making them prospective in nature for the purpose of demonstrating device performance against established standards.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This section is not applicable as the device is a biological indicator, and its performance is measured against objective, quantifiable parameters (spore count, D-value, z-value, survival/kill times, growth/no growth). The determination of "ground truth" (i.e., whether sterilization was successful or not) is based on the biological response of the indicator itself, not on human expert interpretation of images or other data that require subjective assessment. The "experts" in this context would be the microbiologists and engineers conducting the tests according to the specified standards (USP, ISO 11138).
4. Adjudication Method for the Test Set
Adjudication methods (like 2+1, 3+1) are typically used for subjective assessments where human interpretation can vary (e.g., medical image diagnosis). For this device, the outcomes of the tests (e.g., positive or negative growth, numerical values for D-value) are objective and determined by laboratory measurement and observation. Therefore, an adjudication method in the traditional sense is not applicable. The results are either within the acceptance criteria (Passed) or not.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is relevant for diagnostic devices that involve human interpretation of results, often comparing human performance with and without AI assistance. The Gke Steri-Record Steam Mini-Bio-Plus SCBI is a biological indicator that provides a direct biological response (growth or no growth) as an indication of sterilization effectiveness. It does not involve human readers interpreting complex data.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
The performance study results essentially demonstrate the standalone performance of the biological indicator itself. The device is designed to function and provide a clear, objective output (color change indicating growth or no growth) without human interpretation affecting the core measurement of sterilization efficacy. The tests (D-value, z-value, survival/kill windows, etc.) directly assess the indicator's intrinsic biological properties and response to sterilization conditions.
7. The Type of Ground Truth Used
The ground truth used for evaluating the Gke Steri-Record Steam Mini-Bio-Plus SCBI's performance can be categorized as a combination of:
- Biological/Microbiological Measurement: The core of the ground truth is the presence or absence of viable Geobacillus stearothermophilus spores and their defined resistance characteristics (D-value, z-value, survival/kill times) when subjected to known, controlled sterilization conditions.
- Reference Standards: The "ground truth" is defined by adherence to internationally recognized and FDA-accepted consensus standards such as USP Biological Indicator for Steam Sterilization, ANSI/AAMI/ISO 11138-1, and ISO 11138-3. These standards rigorously define how D-values, z-values, and survival/kill windows should be measured and what constitutes an effective biological indicator. The "truth" is established by these standardized methodologies.
8. The Sample Size for the Training Set
This concept is not applicable to the Gke Steri-Record Steam Mini-Bio-Plus SCBI. This is not an AI/ML device that requires a "training set" of data to learn patterns or make predictions. It is a biological device with inherent physical and biological properties. Its performance is demonstrated through empirical testing against established standards, not through "training" an algorithm.
9. How the Ground Truth for the Training Set Was Established
As noted above, a "training set" is not applicable. The device's performance is verified directly through laboratory testing against predefined, objective biological and physical parameters outlined in international standards for biological indicators.
§ 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).