(140 days)
The X100 with Field Peripheral Blood Smear Application is intended to locate and display images of white cells, red cells, and platelets acquired from fixed and stained peripheral blood smears and assists a qualified technologist in conducting a WBC differential, RBC morphology evaluation, and platelet estimate using those images. For in vitro diagnostic use only. For professional use only.
X100 with Full Field Peripheral Blood Smear Application (Scopio's Full Field PBS) automatically locates and presents high resolution digital images from fixed and stained peripheral blood smears. The user browses through the imaged smear to gain high-level general impressions of the sample. In conducting white blood cells (WBC) differential, the user reviews the suggested classification of each automatically detected WBC, and may manually change the suggested classification of any cell. In conducting red blood cells (RBC) morphology evaluation, the user can characterize RBC morphology on observed images. In conducting platelets estimation, the user reviews each automatically detected platelet and the suggested platelet estimation, and may manually change the detections or the estimation. The X100 with Full Field Peripheral Blood Smear Application is intended to be used by skilled users, trained in the use of the device and in the identification of blood cells.
The provided text describes the performance data for the X100 with Full Field Peripheral Blood Smear Application, comparing its results to those achieved by using a manual light microscope, which serves as the reference method.
Here's a breakdown of the requested information:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state pre-defined acceptance criteria for the percentage values (e.g., correlation coefficient, efficiency, sensitivity, specificity). However, it consistently states that "All method comparison testing met acceptance criteria." This implies that the achieved performance met internal or regulatory thresholds. Based on the provided performance data, here's a table:
| Test/Measurement | Acceptance Criteria (Implicitly Met) | Reported Device Performance |
|---|---|---|
| WBC Correlation (Deming Regression r) | Met Acceptance | |
| Neutrophil (%) | Not explicitly stated | 98% |
| Lymphocyte (%) | Not explicitly stated | 96% |
| Monocyte (%) | Not explicitly stated | 95% |
| Eosinophil (%) | Not explicitly stated | 98% |
| WBC Differential (Efficiency) | Met Acceptance | |
| Morphological Abnormality | Not explicitly stated | 96.82% (96.12% to 97.43% CI) |
| Distributional Abnormality | Not explicitly stated | 95.75% (94.95% to 96.46% CI) |
| Overall WBC | Not explicitly stated | 96.29% (95.77% to 96.76% CI) |
| WBC Differential (Sensitivity) | Met Acceptance | |
| Morphological Abnormality | Not explicitly stated | 85.46% (80.19% to 89.78% CI) |
| Distributional Abnormality | Not explicitly stated | 88.83% (85.94% to 91.31% CI) |
| Overall WBC | Not explicitly stated | 87.86% (85.38% to 90.06% CI) |
| WBC Differential (Specificity) | Met Acceptance | |
| Morphological Abnormality | Not explicitly stated | 97.79% (97.16% to 98.31% CI) |
| Distributional Abnormality | Not explicitly stated | 97.43% (96.70% to 98.03% CI) |
| Overall WBC | Not explicitly stated | 97.62% (97.16% to 98.02% CI) |
| RBC Morphology (Overall Agreement) | Met Acceptance | |
| Overall | Not explicitly stated | 99.77% (99.71% to 99.83% CI) |
| Color Group | Not explicitly stated | 99.49% (99.14% to 99.73% CI) |
| Shape Group | Not explicitly stated | 99.77% (99.68% to 99.84% CI) |
| Size Group | Not explicitly stated | 99.61% (99.36% to 99.78% CI) |
| Inclusions Group | Not explicitly stated | 100.00% (99.93% to 100.00% CI) |
| Arrangement Group | Not explicitly stated | 96.65% (95.52% to 97.57% CI) |
| Platelet Estimation (Deming Regression r) | Met Acceptance | |
| Platelets Estimation (10^3/μL) | Not explicitly stated | 94% |
| Platelet Estimation (Efficiency) | Met Acceptance | |
| Overall | Not explicitly stated | 94.89% (92.78% to 96.53% CI) |
| Platelet Estimation (Sensitivity) | Met Acceptance | |
| Overall | Not explicitly stated | 90.00% (83.51% to 94.57% CI) |
| Platelet Estimation (Specificity) | Met Acceptance | |
| Overall | Not explicitly stated | 96.28% (94.11% to 97.82% CI) |
2. Sample size used for the test set and the data provenance
- Sample Size for Test Set: A total of 645 specimens.
- 335 specimens were from normal (healthy) subjects.
- 310 specimens were from subjects with specific disease conditions.
- Data Provenance:
- Country of Origin: Not explicitly stated. The study was conducted at "three sites" but their geographical location is not specified.
- Retrospective or Prospective: Not explicitly stated, but the description "specimens were collected and analyzed at three sites" with slides being "randomly selected, blinded and read" suggests a prospective or at least prospectively designed evaluation of collected samples.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of Experts: "two examiners at each site." Since there were three sites, a total of 6 examiners were involved in establishing the ground truth.
- Qualifications of Experts: The document states that the ground truth was established by "trained examiners" using a "manual light microscope." It also mentions elsewhere that the device is intended for "skilled users, trained in the use of the device and in the identification of blood cells." While specific certifications or years of experience are not detailed, the implication is that these examiners are qualified clinical laboratory professionals adept at manual blood smear analysis.
4. Adjudication method for the test set
- The text states, "The slides were randomly selected, blinded and read by two examiners at each site." It does not explicitly mention a formal adjudication method (e.g., 2+1, 3+1 consensus). It simply states that results were compared between the "Test Method" (X100) and the "Reference Method" (manual light microscope). It is implied that the manual readings by the two examiners constituted the reference. There is no information provided about how discrepancies between the two examiners' manual readings (if any) were resolved or if their results were averaged.
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
- No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with AI assistance vs. without AI assistance was not the primary focus described.
- The study primarily functions as a method comparison study, comparing the device's performance (which assists human readers) directly against the manual light microscope method (the established reference/ground truth).
- The device "assists a qualified technologist" by locating and displaying images and suggesting classifications. The study evaluates the device-assisted technologist's performance against the manual technologist's performance.
- Therefore, an "effect size of how much human readers improve with AI vs without AI assistance" is not reported in the context of a dedicated MRMC study.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- No, a standalone (algorithm-only) performance was not described or evaluated.
- The device's intended use and the study design clearly state that it "assists a qualified technologist." The performance data reflects the combined system of the device and the human user, where the user reviews and can modify the device's suggestions (e.g., "may manually change the suggested classification of any cell," "may manually change the detections or the estimation"). It is a human-in-the-loop system.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- The ground truth was established by expert readings using a manual light microscope. This is effectively expert consensus if the two examiners at each site agreed, or if their readings were somehow combined to form the reference. The manual light microscope process itself is described as the "Reference Method."
8. The sample size for the training set
- The document does not specify the sample size for the training set. The performance data provided is solely for the "Method Comparison" study, which used the 645 specimens as the test set.
9. How the ground truth for the training set was established
- The document does not provide details on how the ground truth for the training set was established. Since the training set size is not mentioned, neither is the method for its ground truth. However, given that the device's "Analysis Technique" for WBCs uses "deterministic artificial neural networks (ANN's) trained to distinguish between classes of white blood cells," it is highly probable that the training ground truth was also established by expert classification of blood cells.
§ 864.5260 Automated cell-locating device.
(a)
Identification. An automated cell-locating device is a device used to locate blood cells on a peripheral blood smear, allowing the operator to identify and classify each cell according to type. (Peripheral blood is blood circulating in one of the body's extremities, such as the arm.)(b)
Classification. Class II (performance standards).