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The BD BACTEC™ Plus Anaerobic/F medium is used in a qualitative procedure for the anaerobic culture and recovery of microorganisms (bacteria) from blood. The principal use of this medium is with the BD BACTEC fluorescent series instruments.

The sample to be tested is inoculated into one or more vials which are inserted into the BD BACTEC fluorescent series instrument for incubation and periodic reading. Each vial contains a chemical sensor which can detect increases in CO2 produced by the growth of microorganisms. The sensor is monitored by the instrument every ten minutes for an increase in its fluorescence, which is proportional to the amount of CO2 present. A positive reading indicates the presumptive presence of viable microorganisms in the vial. Detection is limited to microorganisms that will grow in a particular type of medium.

The provided text describes a 510(k) premarket notification for a medical device called the "BD BACTEC Plus Anaerobic/F (plastic)" medium. This device is an anaerobic blood culture medium used with BD BACTEC fluorescent series instruments for the qualitative culture and recovery of microorganisms from blood. The 510(k) summary focuses on demonstrating substantial equivalence to a predicate device, the "BD BACTEC Plus Anaerobic/F" medium (glass bottle).

The acceptance criteria for this type of device are primarily tied to demonstrating equivalent performance to a legally marketed predicate device across several analytical performance metrics. The study described is a series of analytical studies comparing the new plastic bottle device to the predicate glass bottle device.

Here's a breakdown of the requested information based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for this 510(k) submission are not explicitly stated as numerical targets in a table format within the document. Instead, the studies aim to demonstrate "equivalent performance" or that differences are "minimal" or "detectable but favoring the new device" compared to the predicate. The performance is reported in terms of comparison to the predicate device.

2. Sample Size Used for the Test Set and Data Provenance

• Instrument Time to Detection: 442 paired sets.
• Percent Recovery: 528 paired sets evaluated, 442 paired sets positive in both devices.
• False Positive Rate: 240 paired sets (80 bottles from each of 3 lots).
• False Negative Rate: 146 paired sets evaluated. 30 sets where only predicate detected, 67 sets where only new device detected.
• Antimicrobial Neutralization Capability: 90 paired sets of medium.
• Reproducibility: Not explicitly stated as a separate sample size, but likely part of the studies above or a dedicated internal study.

Data Provenance: The document does not explicitly state the country of origin of the data or whether it was retrospective or prospective. Given it's a 510(k) submission for a diagnostic device, the studies are typically conducted internally by the manufacturer (Becton, Dickinson and Company, located in Sparks, MD, USA) and would be prospective analytical studies. The blood used in the False Positive Rate study is specified as "fresh human blood."

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

This type of device, a microbial growth monitor, relies on objective measurements (e.g., CO2 detection via fluorescence, terminal subculture results) rather than subjective expert interpretation of images or clinical findings. Therefore, the concept of "experts establishing ground truth" in the manner of radiologists reading images is not directly applicable.

• Ground Truth Establishment: The ground truth for positive/negative growth, or false positive/negative, is established by the instrument's detection algorithm, and in cases of non-detection, by terminal subculture (a microbiological laboratory procedure).

4. Adjudication Method for the Test Set

Adjudication methods like "2+1" or "3+1" are typically used when there is subjective human interpretation involved to resolve disagreements. As mentioned above, the ground truth for this device's performance is based on objective instrument readings and laboratory subculture results. Therefore, no human adjudication method is described or applicable.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs without AI Assistance

This is not an AI-based diagnostic imaging device. It is a microbial growth monitor. Therefore, an MRMC comparative effectiveness study involving human readers and AI assistance is not applicable and was not performed.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

The device itself is essentially "standalone" in its primary function as a microbial growth monitor. The BD BACTEC fluorescent series instruments perform the detection automatically based on their internal algorithms to monitor CO2 production. Human intervention would involve technicians loading samples, interpreting instrument flags, and performing confirmatory tests (like subcultures) for non-detecting or potentially false-negative bottles. The performance metrics reported (TTD, recovery, false positive/negative rates) directly reflect the algorithm's performance within the instrument system, without human "reading" of the sensor.

7. The Type of Ground Truth Used

The ground truth used primarily consists of:

• Instrument-detected positivity/negativity: Based on the BD BACTEC fluorescent series instrument's chemical sensor and detection algorithms for CO2 production.
• Terminal Subculture: For vials that did not detect positive by the instrument, a terminal subculture was performed to definitively determine if viable microorganisms were present (e.g., to confirm false negatives). This is a standard microbiological laboratory method.
• Controlled Inoculation: For studies like False Positive Rate and Antimicrobial Neutralization Capability, the ground truth is established by the known inoculation of organisms and/or antimicrobials.

8. The Sample Size for the Training Set

The document does not provide information on a "training set" in the context of machine learning or AI. This is a traditional medical device (a culture medium in a plastic bottle) with an associated instrument that uses a pre-defined algorithm for detection. The development of the medium and the instrument's algorithm would have involved internal validation and optimization, but the term "training set" doesn't apply in the typical AI/ML sense.

9. How the Ground Truth for the Training Set Was Established

As mentioned above, the concept of a "training set" for AI/ML does not apply directly to this device. The development and optimization of the BACTEC instrument's detection algorithm and the culture medium formulation would have been based on established microbiological principles, internal research and development studies, and performance data from prior versions of the device, rather than a distinct "training set" with ground truth established for supervised learning.

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