SEKK SUMMARY STATISTICS EQA round: DIF2/21 - Peripheral Blood Morphology Evaluation Deadline (EQA round closed): 28.05.2021 Key: ELG ... expert laboratories group > ... possible result (found by ELG, but consensus not reached) AV, >>> ... assigned value type CVE (consensus of ELG) RAR ... range of acceptable results RoM ... robust average of all results Sample A Sample B AV RAR RoM AV RAR RoM

WBC - differential count Blasts 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Promyelocytes 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Neutrophil myelocytes 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Neutrophil metamyelocytes 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Neutrophil bars 0,0010,000 - 0,018 0,003 0,0020,000 - 0,018 0,004 Segmented neutrophil granulocytes 0,5550,483 - 0,625 0,579 0,5750,503 - 0,644 0,584 Eosinophils - immature forms 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Eosinophil segmented granulocytes 0,0690,039 - 0,115 0,060 0,0160,003 - 0,043 0,018 Basophilic granulocytes 0,0110,001 - 0,036 0,011 0,0070,000 - 0,028 0,007 Monocytes 0,0660,035 - 0,109 0,067 0,0640,035 - 0,109 0,059 Lymphocytes 0,2980,237 - 0,369 0,278 0,3310,265 - 0,400 0,326 Plasma cells 0 0,000 - 0,018 0,000 0 0,000 - 0,018 0,000 Erythroblasts (number) 0 0,000 - 2,000 0,000 0 0,000 - 3,000 0,002 Sample A Sample B WBC - morphology 23 No changes 15 % >>> 89 No changes 59 % 4 Hypergranulation/ 2,6 % 2 Hypergranulation/toxic granulation 1,3 % 10 Agranulation 6,6 % 2 Agranulation 1,3 % > 78 Hypersegmented granulocytes 52 % 3 Hypersegmented granulocytes 2,0 % 6 Atypical/reactive/pathological monocytes/promono. 4,0 % 1 Hyposegmentation / asegmentation / pelgeroid 0,7 % 9 Denuded nuclei/cells, nuclear shadows / smudge cells 6,0 % 1 Döhle bodies 0,7 % >>> 58 Vacuolisation 38 % 6 Denuded nuclei/cells, nuclear shadows / smudge cells 4,0 % 1 LGL/big lymphocytes 0,7 % 7 Vacuolisation 4,6 % 45 Lymphocytes - reactive forms 30 % 20 LGL/big lymphocytes 13 % 10 Lymphocytes - atypical forms (except "hairy") 6,6 % > 40 Lymphocytes - reactive forms 26 % 1 Lymphocytes - atypical forms (except "hairy") 0,7 % WBC - relative changes of count > 46 Normal count 30 % >>> 140 Normal count 93 % 1 Neutrophilia 0,7 % 4 Basophilia 2,6 % 2 Lymphocytopenia 1,3 % 7 Left shift 4,6 % > 96 Eosinophilia 64 % > 36 Basophilia 24 % 6 Left shift 4,0 % RBC - morphology >>> 102 No changes 68 % >>> 138 91 % 43 Normocytosis 28 % >>> 143 95 % 3 2,0 % 44 29 % 7 Anisocytosis 4,6 % >>> 140 Eliptocytes, ovalocytes 93 % 3 Poikilocytosis 2,0 % 12 Spherocytes 7,9 % 12 Eliptocytes, ovalocytes 7,9 % 18 Stomatocytes 12 % 4 Spherocytes 2,6 % 1 Drepanocytes 0,7 % 13 Stomatocytes 8,6 % >>> 103 Dacryocytes 68 % 4 Dacryocytes 2,6 % 5 3,3 % 1 Acanthocytes 0,7 % 13 8,6 % 7 Echinocytes 4,6 % >>> 136 Target cells 90 % 3 Target cells 2,0 % > 34 (and other fragmentocytes) 23 % 1 Schistocytes (and other fragmentocytes) 0,7 % >>> 84 Polychromasia 56 % 5 Polychromasia 3,3 % >>> 136 Hypochromia 90 % 1 Hypochromia 0,7 % >>> 142 94 %

Printed 02.06.2021, summary evaluation of the results should be found at http://www.sekk.cz Page: 1 SEKK DIF2/21 - Peripheral Blood Morphology Evaluation Sample A Sample B RBC - morphology 3 Basophilic stippling 2,0 % 7 Howell-Jolly bodies 4,6 % 2 Howell-Jolly bodies 1,3 % 1 Cabot rings 0,7 % 1 formation 0,7 % 14 Rouleaux formation 9,3 % 1 0,7 % 2 Pappenheimer bodies 1,3 % Platelets - morphology 10 No changes 6,6 % > 76 No changes 50 % >>> 140 Large platelets 93 % > 71 Large platelets 47 % 13 Small platelets 8,6 % 4 Small platelets 2,6 % 3 Platelet aggregates 2,0 % 11 Platelets hypogranulation 7,3 % > 34 Platelets hypogranulation 23 % 1 Megakaryocytic nucleus fragments 0,7 % 3 Megakaryocytic nucleus fragments 2,0 % Clinical recommendation - smear >>> 128 Blood smear is pathological 85 % >>> 133 Blood smear is pathological 88 % 23 Blood smear within physiological limits or with reactive changes 15 % 18 Blood smear within physiological limits or with reactive changes12 % Clinical recommendation - examination >>> 137 An examination by the specialist/haematologist is recommended 91 % >>> 139 An examination by the specialist/haematologist is recommended 92 % 14 An examination by the specialist/haematologist is not necessary 9,3 % 11 An examination by the specialist/haematologist is not necessary 7,3 % Diagnosis - anaemia 1 Microcytosis 0,7 % 10 Exact determination impossible 6,6 % 1 Hypochromia 0,7 % 1 Normocytosis 0,7 % 1 Thalassemia and other congenital anaemias 0,7 % >>> 104 Microcytosis 69 % 57 Hypochromia 38 % 1 Haemolytic 0,7 % >>> 52 Thalassemia and other congenital anaemias 34 % Diagnosis - myelodysplastic syndrome 1 Myelodysplastic syndrome 0,7 % Diagnosis - chronic myeloproliferative disease > 44 Exact determination impossible 29 % 1 Polycythemia vera 0,7 % > 45 Polycythemia vera 30 % 45 Essential thrombocythemia 30 % Diagnosis - platelets disorders 42 Thrombocytosis 28 % 1 Thrombocytosis 0,7 % 4 Other findings 2,6 % Diagnosis - other 1 Viral infection incl. inf. mononucleosis 0,7 % 1 Viral infection incl. inf. mononucleosis 0,7 % 1 Parasitic infection 0,7 % 1 Allergy 0,7 % 4 Other reactive changes 2,6 % 6 Allergy 4,0 % 2 Other disease 1,3 % Smear quality 148 Acceptable 98 % 147 Acceptable 97 % 3 Not acceptable (give a reason) 2,0 % 4 Not acceptable (give a reason) 2,6 % Staining 131 Acceptable 87 % 129 Acceptable 85 % 18 Not acceptable (give a reason) 12 % 20 Not acceptable (give a reason) 13 % Evaluation of the results - scoring system DIF2/21 Sample A Sample B Maximal achievable score: 69 Maximal achievable score: 111 Successful participants (success 60 % and more): 144 (it is 95 %) Successful participants (success 60 % and more): 148 (it is 98 %) Minimal success in this round: 42,0 % Minimal success in this round: 52,3 % Maximal success in this round: 100,0 % Maximal success in this round: 100,0 % Number of participants: 151 in both samples: 143 (it is 95 %) Number of the participants that succeeded: in one sample: 6 (it is 4 %) in no sample: 2 (it is 1 %)

Printed 02.06.2021, summary evaluation of the results should be found at http://www.sekk.cz Page: 2