Synthetic data only. Never enter patient information; nothing is sent or stored. For clinicians. Not FDA cleared.For licensed clinicians. Educational demonstration on synthetic data. Never enter real patient identifiers or protected health information: everything runs in your browser and nothing is sent or stored. Clinical decision support only; not FDA cleared; physician review is required.
CPE-011 · version 1.0.0
Anemia Classification Pattern Engine: morphology, marrow response and the pattern behind the anemia
WHO thresholds, MCV, reticulocyte production index, and etiologic patterns that fire or stay quiet. No scores, no ranking by probability.
Anemia is a finding with a short list of first questions: how severe, what size are the cells, and is the marrow responding. The Anemia Classification Pattern Engine answers them with WHO thresholds, MCV and the reticulocyte production index, then shows which etiologic patterns fire with the values entered.
It started as a prototype that ranked nine hypotheses with a weighted confidence score. Here each pattern either fires or does not, with the values that fired it, and the iron, B12/folate, kidney and thyroid patterns hand off to their own engines. Urgent situations such as severe anemia, an abrupt fall, thrombotic microangiopathy, overt bleeding and blasts come first.
Playground
Load a synthetic case or type your own values. The result recomputes as you type, and every rule links to its page.
Morphology
● Microcytic
MCV <80 fL
○ Normocytic
MCV 80–100 fL
○ Macrocytic
MCV >100 fL
Marrow response (reticulocyte production index)
● Inadequate · RPI <2
Hypoproliferative: deficiency, inflammation, kidney, marrow
○ Appropriate · RPI ≥2
Blood loss, hemolysis or recovery
CBC and reticulocytes
- <7
- 7–8
- 8–11
- 11–13
- ≥13
Patient
Iron, vitamins and inflammation
Hemolysis, kidney and thyroid
250 U/L is assumed when empty.
Blood film and other context
What it does
- Classifies presence and severity against WHO thresholds, including the pregnancy threshold.
- Classifies morphology by MCV, and calculates the Mentzer index, corrected reticulocyte count and reticulocyte production index.
- Fires deterministic patterns: iron deficiency, inflammation, thalassemia trait, megaloblastic, hemolysis, blood loss, anemia of CKD, cytopenias, and non-vitamin causes of macrocytosis.
- Flags mixed anemia when a high RDW sits on a normal MCV.
- Escalates severe anemia, a fall of 2 g/dL or more, schistocytes with thrombocytopenia, overt bleeding and blasts.
What it never does
- Rank causes by a confidence score or probability.
- Recommend transfusion or any treatment.
- Name a bone-marrow diagnosis.
- Treat a lab trend as a diagnosis.
Safety gates
These gates run before the pattern is shown, and urgent findings are displayed first.
- Hemoglobin below 7 g/dL, or below 8 with chest pain, dyspnea at rest or syncope, raises an urgent alert.
- A fall of 3 g/dL or more raises an urgent alert; 2 g/dL raises a priority review.
- Schistocytes with platelets below 100 raise a thrombotic-microangiopathy alert; blasts or WBC above 30 raise a leukemia alert.
- Pancytopenia or anemia with platelets below 50 raises a priority hematology review.
Inputs
- Hemoglobin, hematocrit, MCV, RDW, RBC count, reticulocytes, WBC, platelets
- Ferritin, transferrin saturation, CRP, B12, folate, MMA
- LDH, haptoglobin, bilirubin, direct antiglobulin test, blood film findings
- eGFR, TSH
- Bleeding, symptoms, liver and alcohol context, prior hemoglobin
Scope
In scope
- Adults aged 18 and over
Routed out
- Patients under 18
The full rule catalog
21 active rules and 1 sandbox or context entries. Each has its own page with conditions, outputs and evidence. 22 of 22 active rules are exercised by at least one synthetic case.
Scope and validity
Classification
Etiologic patterns
AN-10
Iron-deficiency pattern
AN-11
Anemia of inflammation pattern
AN-12
Thalassemia-trait pattern
AN-13
Megaloblastic pattern
AN-14
Hemolysis pattern
AN-15
Blood-loss pattern
AN-16
Anemia-of-CKD pattern
AN-17
Cytopenias: marrow involvement possible
AN-18
Macrocytosis from non-vitamin causes
AN-19
Hypothyroid contribution
Safety
Missing data
Calculations
Synthetic cases
Every case is synthetic. Open one to see the inputs, the full result and the rule trace; then change the values.
ANEM-FX-01
Microcytic anemia with low ferritin
A 36-year-old, Hb 9.9, MCV 72, ferritin 6, TSAT 7%.
ANEM-FX-02
Microcytic anemia, normal iron indices and a low Mentzer index
MCV 62, RBC 5.7.
ANEM-FX-03
Macrocytic anemia with low B12 and hypersegmented neutrophils
MCV 112.
ANEM-FX-04
Hemolysis: reticulocytes 12%, LDH 640, haptoglobin 5
Spherocytes and a positive DAT.
ANEM-FX-05
Anemia in CKD
eGFR 28, normocytic, low reticulocytes, iron replete.
ANEM-FX-06
Anemia of inflammation
CRP 30, ferritin 340, TSAT 12%.
ANEM-FX-07
Pancytopenia
Hb 8.5, WBC 2.4, platelets 62.
ANEM-FX-08
Schistocytes with platelets 40
A thrombotic microangiopathy pattern.
ANEM-FX-09
Hemoglobin 6.4 g/dL
Severe anemia.
ANEM-FX-10
Hemoglobin fell from 13.2 to 9.8
A fall of 3.4 g/dL.
ANEM-FX-11
Fall of 2.3 g/dL
Priority, not urgent.
ANEM-FX-12
Melena and Hb 8.9
Overt gastrointestinal bleeding.
ANEM-FX-13
Blasts on the film
WBC 41.
ANEM-FX-14
High RDW with a normal MCV
Two processes possible.
ANEM-FX-15
Macrocytosis with alcohol use disorder
No vitamin deficiency on the labs.
ANEM-FX-16
Normocytic anemia and a raised TSH
TSH 11.
ANEM-FX-17
No anemia
Hemoglobin 14.1.
ANEM-FX-18
Anemia in pregnancy at 10.6 g/dL
The pregnancy threshold is 11.
ANEM-FX-19
A 15-year-old is outside the adult pathway
Pediatric patient.
ANEM-FX-20
Anemia without any studies
Only a hemoglobin and MCV.
ANEM-FX-21
Microcytic anemia and a low reticulocyte index with a missing ferritin
First-line studies incomplete.
ANEM-FX-22
Blood loss with a reticulocyte response
Retic 5% and a source.
ANEM-FX-23
Severe anemia with dyspnea
Hb 7.6 with symptoms.
ANEM-FX-24
Hemolysis markers without a reticulocyte response
A DAT-positive case.
Evidence
Guidelines and references the rules cite. Each rule page lists the ones that support it.
EV-WHO-HB-2011World Health Organization. Haemoglobin concentrations for the diagnosis of anaemia and assessment of severity. Geneva: WHO; 2011.
Supports: Anemia thresholds and severity grades
EV-TEFFERI-2003Tefferi A. Anemia in adults: a contemporary approach to diagnosis. Mayo Clin Proc. 2003;78(10):1274-1280.
Supports: Classification by MCV and reticulocyte response; first-line studies
EV-CAMASCHELLA-2015Camaschella C. Iron-deficiency anemia. N Engl J Med. 2015;372(19):1832-1843.
Supports: Iron deficiency and anemia of inflammation
EV-MENTZER-1973Mentzer WC Jr. Differentiation of iron deficiency from thalassaemia trait. Lancet. 1973;1(7808):882.
Supports: Mentzer index below 13 favors thalassemia trait
EV-DEVALIA-2014Devalia V, Hamilton MS, Molloy AM; British Committee for Standards in Haematology. Guidelines for the diagnosis and treatment of cobalamin and folate disorders. Br J Haematol. 2014;166(4):496-513.
Supports: Megaloblastic anemia and its evaluation
EV-JAGER-2020Jäger U, Barcellini W, Broome CM, et al. Diagnosis and treatment of autoimmune hemolytic anemia in adults: Recommendations from the First International Consensus Meeting. Blood Rev. 2020;41:100648.
Supports: Hemolysis markers and direct antiglobulin testing
EV-KDIGO-ANEMIA-2012KDIGO Anemia Work Group. KDIGO Clinical Practice Guideline for Anemia in Chronic Kidney Disease. Kidney Int Suppl. 2012;2(4):279-335.
Supports: Evaluation of anemia in CKD
EV-ISTH-TTP-2020Zheng XL, Vesely SK, Cataland SR, et al. ISTH guidelines for the diagnosis of thrombotic thrombocytopenic purpura. J Thromb Haemost. 2020;18(10):2486-2495.
Supports: Schistocytes with thrombocytopenia: urgent evaluation including ADAMTS13
EV-AGA-2020Ko CW, Siddique SM, Patel A, et al. AGA Clinical Practice Guidelines on the Gastrointestinal Evaluation of Iron Deficiency Anemia. Gastroenterology. 2020;159(3):1085-1094.
Supports: Gastrointestinal evaluation of iron-deficiency anemia
Frequently asked questions
How does it classify anemia?
By WHO hemoglobin thresholds (13.0 g/dL for men, 12.0 for non-pregnant women, 11.0 in pregnancy), with severity mild, moderate (below 11) or severe (below 8), and by MCV: microcytic below 80 fL, normocytic 80 to 100, macrocytic above 100.
What is the reticulocyte production index?
The corrected reticulocyte count (reticulocyte % × hematocrit ÷ 45) divided by a maturation factor that depends on the hematocrit. An index of 2 or more means the marrow is responding appropriately, which points to blood loss or hemolysis; below 2 is a hypoproliferative anemia.
Does it still use a confidence score?
No. The prototype this engine came from ranked hypotheses with a weighted score. That has been replaced: each pattern fires or does not, and shows the values that fired it. Several patterns can fire together.
How does it relate to the iron, B12 and kidney engines?
When its iron-deficiency, megaloblastic or CKD pattern fires, the engine points to the dedicated engine, which applies the full rules for that condition, including the gastrointestinal-evaluation and folic-acid-before-B12 safety rules.
What counts as urgent?
Hemoglobin below 7, or below 8 with cardiopulmonary symptoms; a fall of 3 g/dL; overt gastrointestinal bleeding; schistocytes with thrombocytopenia; and blasts or marked leukocytosis. In each case the engine says the routine outpatient pathway is not appropriate and leaves the decision to the physician.
Specification status: Executable specification v1.0.0, ported by Biod from the CBC_ANEMIA_001 prototype and rewritten as deterministic rules. Reviewed by Dr. Vinicius Amaral, D.O. Not for clinical production use.
Clinical review: Dr. Vinicius Amaral, D.O., Medical reviewer, 2026-10-03.
Keep going
CPE-004
Iron Deficiency Pattern Engine
Iron status from ferritin and transferrin saturation, read correctly when inflammation, heart failure or kidney disease changes the rules.
CPE-009
Vitamin B12 and Folate Pattern Engine
Serum B12, MMA and homocysteine read together, folic acid never ahead of B12, and neurologic involvement kept in front.
CPE-003
Chronic Kidney Disease Pattern Engine
No CKD label from a single result. Safety gates run first, then chronicity, then CGA.
Game
Pattern challenge
Guess what the engine will report.
Try Biod in your practice
The Clinical Intelligence Layer — transforming fragmented clinical information into structured intelligence for clinician review and action.