(79 days)
The ALIBI biological indicator is used to monitor the efficacy of ethylene oxide sterilization cycles.
ALIBI is a biological indicator that complies with the USP XXV:2002 monograph Biological Indicator for Ethylene Oxide Sterilization, Paper Carrier. The ALIBI biological indicator consists of a paper carrier inoculated with of Bacillus subtilis var. niger ATCC 9372 bacterial endospores, and a primary package made of glassine. After exposure to an ethylene oxide sterilization cycle, the biological indicator is incubated in soybean casein digest broth at 30-35°C for 7 days. Growth of biological indicator spores is evidenced by the presence of turbidity in the growth medium. If the sterilization cycle killed all of the biological indicator spores, the growth medium remains clear.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (from USP XXV:2002) | Reported Device Performance (ALIBI Biological Indicator) |
|---|---|
| Population values (number of spores) | "Remain within the acceptance criteria in USP XXV" (through real-time data up to 12 months) |
| Purity values | "Remain within the acceptance criteria in USP XXV" (through real-time data up to 12 months) |
| DEO-value (D-value for Ethylene Oxide) | "Remain within the acceptance criteria in USP XXV" (through real-time data up to 12 months) |
| Survival time | "Each lot is evaluated for... survival time." (No specific value given, but implied to be within criteria due to overall statement) |
| Kill time | "Each lot is evaluated for... kill time." (No specific value given, but implied to be within criteria due to overall statement) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: "Stability studies on three lots manufactured from three different spore crops are in progress." This implies a test set of three lots (each from a different spore crop).
- Data Provenance: The study is described as "Real time data through the 12 months test interval." This indicates the data is prospective and collected over time during the stability study. The country of origin is not explicitly stated, but the company (Arden Laboratories, Inc.) is based in Willernie, Minnesota, USA.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This information is not applicable as the device is a biological indicator for sterilization, not a medical imaging or diagnostic device requiring expert interpretation. The ground truth is objective (presence or absence of microbial growth).
4. Adjudication Method for the Test Set
This information is not applicable for the same reasons as above. The determination of growth or no growth is based on a clear, objective biological outcome (turbidity in the growth medium).
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. This type of study is typically performed for diagnostic or screening devices where human interpretation is involved. The ALIBI Biological Indicator is a device to monitor sterilization efficacy, not for human interpretation of medical cases.
6. If a Standalone Study (Algorithm Only Without Human-in-the-Loop Performance) Was Done
Yes, the evaluation of the ALIBI Biological Indicator is a standalone performance study. The device is used independently to indicate the efficacy of the sterilization cycle without direct human interpretation influencing the end result (turbidity development). The "algorithm" here is the biological process of spore inactivation and subsequent growth/no-growth, which is assessed objectively.
7. The Type of Ground Truth Used
The ground truth used is based on biological outcome:
- Presence of turbidity: Indicates survival of biological indicator spores (sterilization failure).
- Growth medium remains clear: Indicates all biological indicator spores were killed (successful sterilization).
This is an objective, empirical ground truth based on microbial viability.
8. The Sample Size for the Training Set
The document does not explicitly mention a separate "training set" in the context of machine learning or AI. This device is a biological indicator validated against established standards. The "training" in a biological sense would be the development and optimization of the spore crop and manufacturing process to consistently meet the USP XXV criteria, which are not detailed as a distinct 'training set' of data.
9. How the Ground Truth for the Training Set Was Established
Since a "training set" in the AI sense is not applicable, the establishment of ground truth for a training set is also not applicable. The underlying principles of what constitutes a "successful" or "failed" sterilization are predefined by the USP XXV monograph, which serves as the ultimate standard for the biological indicator's performance.
§ 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).