X100/X100HT with Full Field Peripheral Blood Smear (PBS) Application

{0} FDA U.S. FOOD & DRUG ADMINISTRATION # 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY INSTRUMENT ONLY ## I Background Information: A 510(k) Number K243144 B Applicant Scopio Labs Ltd. C Proprietary and Established Names X100 with Full Field Peripheral Blood Smear (PBS) Application X100HT with Full Field Peripheral Blood Smear (PBS) Application D Regulatory Information | Product Code(s) | Classification | Regulation Section | Panel | | --- | --- | --- | --- | | JOY | Class II | 21 CFR 864.5260 - Automated Cell-Locating Device | HE - Hematology | ## II Submission/Device Overview: A Purpose for Submission: This submission is for the addition of a Decision Support System (DSS) to support the user's review of red blood cell (RBC) morphology and platelet clumps. B Type of Test: White blood cell (WBC) differential, red blood cell (RBC) morphology evaluation and platelet estimation ## III Intended Use/Indications for Use: A Intended Use(s): See Indications for Use below. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993-0002 www.fda.gov {1} B Indication(s) for Use: The X100/X100HT with Full 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. C Special Conditions for Use Statement(s): Rx - For Prescription Use Only IV Device/System Characteristics: A Device Description: The X100/X100HT with Full Field Peripheral Blood Smear (PBS) Application (“Full Field PBS”) automatically locates and presents images of blood cells on peripheral blood smears. The user browses through the imaged smear to gain a high-level general impression. The user reviews the suggested classification of each white cell according to type and may manually change the suggested classification of any cell. The user reviews and may manually change the suggested platelet estimation as well. In this modified version, a decision support system (DSS) has been added to support the user’s review of red blood cell (RBC) morphology and platelet clumps. The DSS’s recommendations are presented to the user by means of a dotted line around the grade or parameter suggested by the DSS. The user is instructed to review the DSS’s suggestions and must actively mark the appropriate selection. The device consists of two main hardware components: the digital scanner (X100/X100HT) and the processing unit. The RBC analysis starts from the center of the monolayer, detecting non-overlapping RBCs at a single region at a time, moving outward in a spiral to analyze additional regions. The analysis process includes two steps – the first step keeps analyzing regions until 10,000 non-overlapping RBCs are detected. These cells are then assigned morphological labels. The final grading is set by converting the morphology percentages of the analyzed cells into grades using the default thresholds recommended by the International Council for Standardization in Hematology (ICSH), that can be modified by the lab director. The platelet clumps detection analyzes the entire monolayer and feathered edge regions of the scan to identify platelet clumps. B Instrument Description Information: 1. Instrument Name(s): X100 with Full Field Peripheral Blood Smear (PBS) Application X100HT with Full Field Peripheral Blood Smear (PBS) Application 2. Specimen Identification: K243144 - Page 2 of 16 {2} The slide's barcode is captured automatically and assigned to each case. The device also supports typing the barcode manually. 3. Specimen Sampling and Handling: A peripheral blood sample collected in K₂EDTA or K₃EDTA tubes is mixed manually or automatically. A thin blood film is wedged on a clean dry glass slide (a blood smear) and stained with Romanowsky stain. After the staining process is completed, the slide is covered using any standard cover slipping method. 4. Calibration: The Full Field PBS system requires initial calibration for its mechanical and optical performances. An initial calibration process is performed on a standard blood smear slide as part of the manufacturing process of the device. The calibration is verified after installation by a technician or a qualified operator. Calibration can also be performed if a problem arises in the daily QC testing. 5. Quality Control: The daily QC involves testing a standard blood smear slide to verify image quality. During the daily QC the user reviews the images received from the Full Field PBS and verifies that at least 95% of the WBCs in the scanned image were identified and located correctly by the system. V Substantial Equivalence Information: A Predicate Device Name(s): X100 with Full Field Peripheral Blood Smear (PBS) Application, X100HT with Slide Loader with Full Field Peripheral Blood Smear (PBS) Application B Predicate 510(k) Number(s): K201301, K220013 C Comparison with Predicate(s): | Device & Predicate Device(s): | K243144 | K201301 | K220013 | | --- | --- | --- | --- | | Device Trade Name | X100/X100HT with Full Field Peripheral Blood Smear Application | X100 with Full Field Peripheral Blood Smear (PBS) Application | X100HT with Full Field Peripheral Blood Smear (PBS) Application | | General Device Characteristic Similarities | | | | | Intended Use/Indications For Use | The X100/X100HT with Full Field Peripheral Blood Smear Application is intended | Same | Same | K243144 - Page 3 of 16 {3} | | 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. | | | | --- | --- | --- | --- | | Intended User | Skilled users, trained in the use of the device and in the identification of blood cells. | Same | Same | | Sample Type | Stained blood film glass slides of peripheral whole blood | Same | Same | | Sample Preparation | Romanowsky stain | Same | Same | | Analysis Technique: White Blood Cells | WBCs are located/counted by moving according to the battlement pattern (ensuring that each cell is counted only once). Cell images are analyzed using standard mathematical methods, including deterministic artificial neural networks (ANN's) trained to distinguish between classes of white blood cells. The cell images are pre-classified, and the user reviews the suggested classification, and accepts or reclassifies the images. | Same | Same | | Analysis Technique: Platelets estimation | Platelets are located/counted by moving according to the | Same | Same | K243144 - Page 4 of 16 {4} | | battlement pattern (ensuring that each cell is counted only once). Cell images are analyzed using standard mathematical methods, including deterministic artificial neural networks (ANN's) trained to detect platelets. The user reviews the suggested estimate of the platelet concentration and accepts or modifies the result. | | | | --- | --- | --- | --- | | Quality Control | The daily QC involves testing a standard blood smear slide. During the daily QC the user reviews the images received from the Full Field PBS and verifies that at least 95% of the WBCs in the scanned image were identified and located correctly by the system. | Same | Same | | High-Resolution Image Acquisition | Fully automated scan and image acquisition. Captures multiple images under plurality of illumination conditions and reconstructs a 100X magnification image of the viewed area, without the need for immersion oil. | Same | Same | | General Device Characteristic Differences | | | | | Analysis Technique: Red Blood Cells | The device presents an overview image to be reviewed by the user. The system presents to the user a dotted line around RBC | The device presents an overview image to be reviewed by the user. The examiner manually grades RBC morphology from the | The device presents an overview image to be reviewed by the user. The examiner manually grades RBC morphology from the | K243144 - Page 5 of 16 {5} K243144 - Page 6 of 16 | | morphology grading suggestions. The examiner manually grades RBC morphology from the image. | image. | image. | | --- | --- | --- | --- | | Analysis Technique: Platelets Clump presence | The device presents an overview image to be reviewed by the user. The system presents to the user a dotted line around a suggestion whether platelet clump was detected. The examiner manually marks if platelet clumps are present in the smear. | The device presents an overview image to be reviewed by the user. The examiner manually marks if platelet clumps are present in the smear. | The device presents an overview image to be reviewed by the user. The examiner manually marks if platelet clumps are present in the smear. | VI Standards/Guidance Documents Referenced: - CLSI EP05-A3: Evaluation of Precision of Quantitative Measurement Procedures; Approved Guideline - Third Edition - CLSI EP12-A2: User Protocol for Evaluation of Qualitative Test Performance; Approved Guideline - Second Edition - CLSI EP17-A2: Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures; Approved Guideline - Second Edition - IEC 62471 First edition 2006-07 Photobiological safety of lamps and lamp systems - ANSI AAMI ISO 14971:2019 Medical Devices – Applications of risk management to medical devices - ANSI UL 61010-1 3rd Ed 2012-05-12 Standard for Safety for Electrical Equipment for Measurement Control and Laboratory Use - ANSI AAMI IEC 62304:2006/A1:2016 Medical device software – Software life cycle processes - ANSI AAMI IEC 62366-1:2015+AMDI:2020 Medical devices Part 1: Application of usability engineering to medical devices VII Performance Characteristics (if/when applicable): A Analytical Performance: 1. Precision/Reproducibility: **Repeatability** {6} Repeatability was conducted at three (3) clinical sites – two (2) US sites and one (1) OUS site, using 27 test samples representing different RBC morphological features as well as platelet clumping. Over the course of 20 testing days, two (2) daily runs were performed using two (2) replicates. The selected samples represented 23 morphological features in different grading levels. In total, 2160 scans were performed. The DSS suggestions from the scans were compared to the assigned reference grades as performed by laboratory professionals. The rate of agreement was calculated for each sample and each morphological feature separately, and each of the rate of agreement results was compared separately to a predefined acceptance criterion of 80%. All results met the pre-defined acceptance criteria. | Morphological Feature | Mean Agreement | | --- | --- | | Acanthocytes | 99% | | Anisocytosis | 99% | | Basophilic stippling | 98% | | Bite cells | 98% | | Blister cells | 98% | | Echinocytes | 98% | | Elliptocytes | 100% | | Helmet cells | 99% | | Howell-Jolly bodies | 98% | | Hypochromia | 96% | | Macrocytes | 100% | | Micro-organisms | 100% | | Microcytes | 100% | | Ovalocytes | 99% | | Pappenheimer bodies | 98% | | Poikilocytosis | 97% | | Polychromasia | 97% | | Schistocytes | 99% | | Sickle cells | 100% | | Spherocytes | 98% | | Stomatocytes | 100% | | Target cells | 99% | | Teardrop cells | 99% | | Platelet clumps | 95% | ## Reproducibility Reproducibility was performed using 16 test samples across three (3) clinical sites, two (2) US sites and one (1) OUS site, with the test samples representing different RBC morphological features as well as platelet clumping. The study was conducted over five (5) testing days with five (5) replicates per day on three (3) devices. All results met the predefined acceptance criteria of 80%. | Morphological Feature | Mean Agreement | | --- | --- | | Acanthocytes | 99% | | Anisocytosis | 99% | K243144 - Page 7 of 16 {7} | Morphological Feature | Mean Agreement | | --- | --- | | Basophilic stippling | 97% | | Bite cells | 97% | | Blister cells | 100% | | Echinocytes | 97% | | Elliptocytes | 99% | | Helmet cells | 99% | | Howell-Jolly bodies | 97% | | Hypochromia | 95% | | Macrocytes | 99% | | Micro-organisms | 99% | | Microcytes | 100% | | Ovalocytes | 98% | | Pappenheimer bodies | 97% | | Poikilocytosis | 97% | | Polychromasia | 96% | | Schistocytes | 99% | | Sickle cells | 99% | | Spherocytes | 99% | | Stomatocytes | 100% | | Target cells | 99% | | Teardrop cells | 99% | | Platelet clumps | 96% | 2. Linearity: Not applicable. 3. Analytical Specificity/Interference: Not applicable. 4. Accuracy (Instrument): ## Method Comparison A method comparison study was conducted to compare the results achieved by trained examiners using the X100 with Full Field Peripheral Blood Smear (PBS) Application with the RBC and Platelet Clump Decision Support System (DSS) and without the RBC and Platelet Clump Decision Support System (DSS). A total of 1200 PBS slides were prepared, each from a different blood sample, from three (3) clinical sites – two (2) US sites and one (1) OUS site, representing RBC morphological features in different grading levels as well as platelet clumping. These samples were collected during routine laboratory workflow of the three sites, represented the range of clinical conditions expected in the target population, and were randomly assigned to the investigators at each site. The samples were split between six (6) investigators (200 samples per investigator) and analyzed in two (2) methods (reference K243144 - Page 8 of 16 {8} and test arms). First, in the reference arm, the samples were assessed using the previously cleared version of the application without DSS assistance. After a three-week washout period, sample anonymization and randomization, the investigators analyzed the same samples in the test arm, using the modified version of the Full Field PBS Application, with DSS suggestions presented to investigators for RBC morphology and platelet clumping. In both arms of the study, the qualified users were provided with a full field scan of their assigned samples, graded the same 23 RBC morphological features according to a predefined 4-graded scale, and evaluated the presence of platelet clumps in each sample. The same images were reviewed with and without the newly introduced DSS for RBC morphological features and indications concerning platelet clump presence. A washout period of three (3) weeks took place between finishing one study arm and starting the second. The results were evaluated according to the categories of morphological features (RBC color, RBC inclusions, RBC shape, RBC size, PLT Clumping) with acceptance criteria applied for each category and each predictive value separately, including 95% confidence intervals measured using 1000 bootstrap iterations. All RBC categories and platelet clumping met the pre-defined acceptance criteria of 80% for overall agreement, PPA and NPA. ## Multi-Center Performance by Morphological Features – All Sites Combined: | Category | PPA (95% CI) | NPA (95% CI) | Overall Agreement (95% CI) | | --- | --- | --- | --- | | RBC Color | 98.33% (97.48%, 99.10%) | 97.61% (96.81%, 98.33%) | 97.88% (97.29%, 98.42%) | | RBC Inclusions | 86.73% (81.66%, 91.23%) | 98.41% (98.06%, 98.78%) | 97.90% (97.50%, 98.27%) | | RBC Shape | 95.35% (94.50%, 96.12%) | 96.40% (96.06%, 96.71%) | 96.22% (95.92%, 96.50%) | | RBC Size | 99.42% (99.03%, 99.75%) | 92.72% (91.82%, 93.70%) | 95.58% (95.06%, 96.13%) | | PLT Clumping | 86.11% (82.13%, 89.91%) | 87.39% (85.39%, 89.3) | 87.08% (85.25%, 88.92%) | ## Results evaluated for each morphological feature separately: K243144 - Page 9 of 16 {9} K243144 - Page 10 of 16 | Morphological Feature | PPA (95% CI) | NPA (95% CI) | Overall Agreement (95% CI) | | --- | --- | --- | --- | | Hypochromia | 99.31% (98.43%, 100.00%) | 96.86% (95.58%, 97.99%) | 97.75% (96.92%, 98.50%) | | Polychromasia | 97.40% (95.92%, 98.72%) | 98.38% (97.48%, 99.20%) | 98.00% (97.17%, 98.75%) | | Basophilic stippling | 96.55% (88.89%, 100.00%) | 99.91% (99.74%, 100.00%) | 99.83% (99.58%, 100.00%) | | Howell-Jolly bodies | 81.56% (74.82%, 87.82%) | 93.96% (92.51%, 95.45%) | 92.50% (91.00%, 93.96%) | | Micro-organisms | 85.71% (50.00%, 100.00%) | 99.92% (99.75%, 100.00%) | 99.83% (99.58%, 100.00%) | | Pappenheimer bodies | 100.00% (100.00%, 100.00%) | 99.40% (98.89%, 99.83%) | 99.42% (98.92%, 99.83%) | | Platelet clumps | 86.11% (82.13%, 89.91%) | 87.39% (85.39%, 89.39%) | 87.08% (85.25%, 88.92%) | | Acanthocytes | 100.00% (100.00%, 100.00%) | 98.82% (98.10%, 99.37%) | 98.91% (98.25%, 99.42%) | | Bite cells | 100.00% (100.00%, 100.00%) | 99.91% (99.74%, 100.00%) | 99.92% (99.75%, 100.00%) | | Blister cells | 88.89% (63.64%, 100.00%) | 99.83% (99.58%, 100.00%) | 99.75% (99.42%, 100.00%) | | Echinocytes | 99.48% (98.70%, 100.00%) | 99.13% (98.37%, 99.64%) | 99.24% (98.65%, 99.66%) | | Elliptocytes | 97.80% (94.19%, 100.00%) | 99.64% (99.27%, 99.91%) | 99.50% (99.08%, 99.83%) | | Helmet cells | 82.46% (72.22%, 92.23%) | 94.23% (93.12%, 95.33%) | 93.67% (92.50%, 94.75%) | | Ovalocytes | 100.00% (100.00%, 100.00%) | 98.52% (97.47%, 99.35%) | 99.24% (98.74%, 99.66%) | | Poikilocytosis | 98.61% (97.39%, 99.55%) | 96.27% (94.99%, 97.46%) | 97.13% (96.19%, 98.05%) | | Schistocytes | 77.17% (71.63%, 82.27%) | 74.51% (71.44%, 77.40%) | 75.17% (72.59%, 77.63%) | | Sickle cells | 98.00% (93.10%, 100.00%) | 99.47% (99.03%, 99.83%) | 99.41% (98.95%, 99.83%) | | Spherocytes | 97.59% (93.72%, 100.00%) | 99.55% (99.11%, 99.91%) | 99.42% (98.92%, 99.83%) | | Stomatocytes | 100.00% (100.00%, 100.00%) | 99.30% (98.77%, 99.74%) | 99.33% (98.83%, 99.75%) | | Target cells | 99.07% (97.84%, 100.00%) | 99.17% (98.48%, 99.71%) | 99.15% (98.55%, 99.57%) | {10} | Morphological Feature | PPA (95% CI) | NPA (95% CI) | Overall Agreement (95% CI) | | --- | --- | --- | --- | | Teardrop cells | 84.78% (80.00%, 88.89%) | 82.24% (79.68%, 84.85%) | 82.89% (80.57%, 85.11%) | | Anisocytosis | 99.34% (98.66%, 100.00%) | 97.98% (96.81%, 99.00%) | 98.67% (98.00%, 99.33%) | | Macrocytes | 99.36% (98.59%, 100.00%) | 88.49% (86.58%, 90.50%) | 92.75% (91.58%, 94.00%) | | Microcytes | 99.57% (98.91%, 100.00%) | 92.66% (90.82%, 94.43%) | 95.33% (94.17%, 96.42%) | RBC Color | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 881 | 36 | 917 | | Test Method Negative | 15 | 1468 | 1483 | | Total | 896 | 1504 | 2400 | RBC Inclusions | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 183 | 73 | 256 | | Test Method Negative | 28 | 4516 | 4544 | | Total | 211 | 4589 | 4800 | RBC Shape | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 2606 | 493 | 3099 | | Test Method Negative | 127 | 13184 | 13311 | | Total | 2733 | 13677 | 16410 | RBC Size | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 1531 | 150 | 1681 | | Test Method Negative | 9 | 1910 | 1919 | | Total | 1540 | 2060 | 3600 | K243144 - Page 11 of 16 {11} Hypochromia | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 432 | 24 | 456 | | Test Method Negative | 3 | 741 | 744 | | Total | 435 | 765 | 1200 | Polychromasia | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 449 | 12 | 461 | | Test Method Negative | 12 | 727 | 739 | | Total | 461 | 739 | 1200 | Basophilic Stippling | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 28 | 1 | 29 | | Test Method Negative | 1 | 1170 | 1171 | | Total | 29 | 1171 | 1200 | Howell-Jolly Bodies | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 115 | 64 | 179 | | Test Method Negative | 26 | 995 | 1021 | | Total | 141 | 1059 | 1200 | Micro-organisms | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 6 | 1 | 7 | | Test Method Negative | 1 | 1192 | 1193 | | Total | 7 | 1193 | 1200 | Pappenheimer Bodies | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 34 | 7 | 41 | | Test Method Negative | 0 | 1159 | 1159 | | Total | 34 | 1166 | 1200 | Acanthocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 97 | 13 | 110 | | Test Method Negative | 0 | 1086 | 1086 | | Total | 97 | 1099 | 1196 | K243144 - Page 12 of 16 {12} Bite cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 41 | 1 | 42 | | Test Method Negative | 0 | 1158 | 1158 | | Total | 41 | 1159 | 1200 | Blister cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 8 | 2 | 10 | | Test Method Negative | 1 | 1189 | 1190 | | Total | 9 | 1191 | 1200 | Echinocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 380 | 7 | 387 | | Test Method Negative | 2 | 800 | 802 | | Total | 382 | 807 | 1189 | Elliptocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 89 | 4 | 93 | | Test Method Negative | 2 | 1105 | 1107 | | Total | 91 | 1109 | 1200 | Helmet Cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 47 | 66 | 113 | | Test Method Negative | 10 | 1077 | 1087 | | Total | 57 | 1143 | 1200 | Ovalocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 583 | 9 | 592 | | Test Method Negative | 0 | 598 | 598 | | Total | 583 | 607 | 1190 | K243144 - Page 13 of 16 {13} K243144 - Page 14 of 16 Poikilocytosis | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 426 | 28 | 454 | | Test Method Negative | 6 | 723 | 729 | | Total | 432 | 751 | 1183 | Schistocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 196 | 194 | 390 | | Test Method Negative | 58 | 567 | 625 | | Total | 254 | 761 | 1015 | Sickle cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 49 | 6 | 55 | | Test Method Negative | 1 | 1136 | 1137 | | Total | 50 | 1142 | 1192 | Spherocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 81 | 5 | 86 | | Test Method Negative | 2 | 1112 | 1114 | | Total | 83 | 1117 | 1200 | Stomatocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 56 | 8 | 64 | | Test Method Negative | 0 | 1130 | 1130 | | Total | 56 | 1138 | 1194 | Target cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 319 | 7 | 326 | | Test Method Negative | 3 | 841 | 844 | | Total | 322 | 848 | 1170 | Teardrop cells | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 234 | 143 | 377 | | Test Method Negative | 42 | 662 | 704 | | Total | 276 | 805 | 1081 | {14} K243144 - Page 15 of 16 Anisocytosis | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 602 | 12 | 614 | | Test Method Negative | 4 | 582 | 586 | | Total | 606 | 594 | 1200 | Macrocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 467 | 84 | 551 | | Test Method Negative | 3 | 646 | 649 | | Total | 470 | 730 | 1200 | Microcytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 462 | 54 | 516 | | Test Method Negative | 2 | 682 | 684 | | Total | 464 | 736 | 1200 | Platelet clumps | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 248 | 115 | 363 | | Test Method Negative | 40 | 797 | 837 | | Total | 288 | 912 | 1200 | Schistocyte Supplemental Study: RBC-DSS vs. manual light microscope To supplement the results for schistocytes, the sponsor conducted a study in which the results for schistocytes using the DSS were compared to the results from manual light microscope. Two experienced operators analyzed 75 slides with a mixture of normal PBS samples without schistocytes and slides containing schistocytes in different grade levels. The slides were reviewed on both the DSS and the manual light microscope with a wash-out period between the two devices. The results are summarized below. Schistocytes | | Reference Method Positive | Reference Method Negative | Total | | --- | --- | --- | --- | | Test Method Positive | 29 | 7 | 36 | | Test Method Negative | 6 | 33 | 39 | | Total | 35 | 40 | 75 | {15} | Morphological Feature | PPA (95% CI) | NPA (95% CI) | Overall Agreement (95% CI) | | --- | --- | --- | --- | | Schistocytes | 82.86% (73.33%, 90.67%) | 82.50% (69.57%, 94.44%) | 82.67% (70.00%, 93.75%) | 5. Carry-Over: Not applicable. B Other Supportive Instrument Performance Characteristics Data: Not applicable. VIII Proposed Labeling: The labeling supports the finding of substantial equivalence for this device. IX Conclusion: The submitted information in this premarket notification is complete and supports a substantial equivalence decision. K243144 - Page 16 of 16