Dig in
Vignettes
Worked progressions, and how to read them through the three layers
Each vignette is one path a user can rebuild in the Explore tab. The logic is always the same. The classifiers (RF and GNN) decide whether a transition is real signal and trim co-occurrence noise. The temporal correlation ρ then measures how tight the ordering is. The genetic correlation rg tests whether biology independently agrees, which separates inherited cascades from acquired, exposure-driven ones. A step with no rg is not weak; for infection and exposure trajectories, silence on genetics is the expected and informative result.
1. Cerebrovascular injury to epilepsy
A cardioembolic source seeds a stroke, and the stroke opens a late path to epilepsy.
How the layers read
The classifiers keep every step, and confidence climbs as the chain becomes more specific, reaching RF 1.00 and GNN 1.00 at the stroke-to-neurology transitions. The temporal correlation is modest early and strengthens into the neurological tail. Genetics corroborate exactly where it matters: the stroke-to-nervous-system step carries rg+0.19 and the nervous-system-to-epilepsy step rg+0.71, so the late, clinically important link is the one biology supports most.
Explore it yourself
Seed on Cerebral infarction in the Nervous system group, set direction to from, and double-click it to build forward. Switch direction to to in order to trace the cardioembolic precedents. Keep the time filter at 90+ days, where this cascade lives.
How to read it
This is the directed-bridge pattern: a transition that is weak as raw co-occurrence but survives because the models and the genetics agree. Read it as a hypothesis that post-stroke epilepsy risk concentrates months out, not as a claim that every stroke leads there.
2. The cardiometabolic cascade
Obesity opens a metabolic sequence that ends at the coronary event, and the genetics tighten at every step.
How the layers read
Each step clears the gate at RF and GNN near 1.00. The temporal correlation is strong through the middle of the chain. The genetic correlations escalate as the chain advances, rg+0.73 from hypertension to lipid disorder, rg+0.77 into coronary disease, and rg+0.98 from coronary disease to the infarction. Type 2 diabetes feeds the same coronary node directly at rg+0.43.
Explore it yourself
Seed on Essential hypertension or Diabetes mellitus, Type 2 in the Circulatory or Endocrine group. Set the genetic layer to genetically supported to keep only the corroborated steps, then build forward.
How to read it
The near-unity genetic correlation between coronary disease and infarction means those two behave as one biological object recorded as a fast 15 to 30 day transition. Read the chain as a window on intervention timing, since the modifiable steps sit early, before the coronary node.
3. Fragility fracture and the musculoskeletal pain module
A fracture acts as a sentinel, and the pain phenotypes form a tight, genetically shared loop.
How the layers read
The classifiers trim hard around osteoarthritis, dropping more than half of its temporally significant transitions as age-confounded noise. What survives is tight, with the strongest steps reaching ρ+0.50. Genetics light up the pain loop, rg+0.61 from low back to general musculoskeletal pain and rg+0.80 from there to osteoarthritis, while the fracture-to-osteoporosis sentinel step is strong on timing but not genetically marked.
Explore it yourself
Seed on Osteoarthritis in the Musculoskeletal group and build forward to see the pain module. Switch direction to to and seed on Osteoporosis to see the fragility-fracture precedent.
How to read it
The high genetic correlations and the near-loop between osteoarthritis and musculoskeletal pain say this is a shared-biology module, not a one-way cascade. The fracture step is the actionable signal, since a fragility fracture may flag both bone and downstream pain trajectories.
4. Ascending infection, sepsis, and chronic heart failure
A bacterial source escalates to sepsis, and sepsis leaves a chronic cardiovascular mark.
How the layers read
Every step clears the gate at RF and GNN at or near 1.00, so the models read this as clean signal rather than incidental co-coding. The temporal correlations are steady across the infectious and the post-sepsis steps. No step carries a genetic correlation, which is expected, because this is an acquired cascade and the classifiers and timing carry the weight while genetics stay silent.
Explore it yourself
Seed on Septicemia in the Infectious group. Build forward to the post-sepsis cardiovascular tail, then switch direction to to in order to recover the infectious origin.
How to read it
The absence of genetic support is the point. A real, model-confident, well-ordered cascade with no genetic correlation is the signature of an exposure-driven trajectory, which is what post-sepsis cardiovascular morbidity should look like.
5. Urinary infection, glomerular injury, and chronic kidney disease
Recurrent infection and proteinuria precede glomerular injury, which settles into chronic kidney disease.
How the layers read
The classifiers keep all steps, with confidence rising into the chronic phase. The temporal correlation strengthens as the kidney injury consolidates, from ρ+0.14 early to ρ+0.60 at the endpoint. The early inflammatory steps are not genetically marked, consistent with acquired injury, while the chronic endpoint reflects shared metabolic-renal biology.
Explore it yourself
Seed on Nephritis; nephrosis; renal sclerosis in the Genitourinary group and build forward to chronic kidney disease. Switch to to in order to surface the proteinuria and infection precedents.
How to read it
The rising correlation tracks a real clinical consolidation, with acute and inflammatory renal signals giving way to a stable chronic state. The endpoint hypothesis is that diabetic kidney disease and other chronic kidney disease share a final common path worth modeling jointly.
6. Inhaled environmental lung injury to cor pulmonale
Lung injury from an external agent drives obstruction, failure, and finally right-heart disease.
How the layers read
The first step is the only soft one, RF 0.81, because external-agent lung disease is heterogeneous, and the gate still keeps it. From obstruction onward the models sit at RF and GNN near 1.00. The temporal correlation peaks at the obstruction-to-failure step. No step carries genetic support, the expected signature of an exposure cascade rather than an inherited one.
Explore it yourself
Seed on Chronic obstructive pulmonary disease and bronchiectasis in the Respiratory group and build forward to pulmonary heart disease. Set the genetic layer to all progressions, since this trajectory is environmental and will not appear under the genetic filter.
How to read it
This is the cleanest environmental example in the set, a directed, model-confident, genetics-silent path from an inhaled exposure to right-heart failure. It is a natural target for linking an external exposure series to a downstream cardiopulmonary endpoint.
7. Nephrotoxic exposure, acute injury, and chronic kidney disease
A drug or toxic exposure precipitates acute kidney injury that hardens into chronic disease.
How the layers read
All steps clear the gate at RF and GNN near 1.00. The temporal correlation jumps at the acute-to-chronic transition to ρ+0.62, the strongest single link in the exposure set, marking where reversible injury becomes permanent. The exposure steps carry no genetic correlation, as expected, while the chronic-renal endpoint reflects shared renal-metabolic biology.
Explore it yourself
Seed on Acute and unspecified renal failure in the Genitourinary group. Build forward to the chronic endpoint, then switch to to in order to recover the toxic exposure trigger.
How to read it
The acute-to-chronic step is the hypothesis: the window where a nephrotoxic exposure stops being recoverable. It is the kind of timing claim the map is built to generate and an exposure study could test.
Generated from the ClaiD corpus (New England, US). Hypothesis-generating associations with timing, not causal claims. Gate: adjusted p ≤ 0.05, RF ≥ 0.70, GNN ≥ 0.70.
ClaiD
Mapping the Phylophenome of Human Disease · pronounced “Clade”
The Vision
Historically, medical research has treated human disease as a series of isolated clinical snapshots. This static approach fails to capture the dynamic, evolving reality of patient health. To truly understand, predict, and alter the course of illness, we must move beyond static phenotypes and map the continuous progression of disease over time. ClaiD, pronounced as Clade, is the foundational architecture built to achieve this. It is a computable, directed temporal knowledge base designed to track, model, and predict the complete evolutionary pathways of human health.
Defining the Phylophenome
ClaiD introduces a new scientific paradigm: the Phylophenome. Just as the genome maps human DNA and the proteome maps proteins, the Phylophenome is the definitive, comprehensive map of all temporal clinical phenotypes. It captures how specific health states interact, mutate, and branch out over a patient's lifespan, transforming complex, longitudinal health records into a structured, computable universe of disease progression.
The Architecture
The Concept of the Clade
The engine’s name, ClaiD, is rooted in both its origin — the Clinical Augmented Intelligence (CLAI) group — and its core structural philosophy derived from phylogenetics.
In evolutionary biology, a clade is a complete branch on the tree of life, containing a single ancestor and all of its descendants. ClaiD applies this exact mathematical and biological structure to clinical informatics:
- The Ancestor: a patient's baseline clinical state or genetic foundation.
- The Descendants: the cascading, branching sequence of subsequent diagnoses, complications, and temporal phenotypes that emerge from that baseline.
Within this framework, a clinical “clade” is a specific, highly detailed temporal trajectory of disease. By mapping these clades, ClaiD enables researchers and autonomous AI systems to trace the exact lineage of a complication back to its root, or look forward to predict the cascading effects of a single medical event.
The Impact
ClaiD is not just a repository; it is a navigational engine. By providing a structured, directed map of human disease trajectories, it creates the essential infrastructure required for the next generation of medical AI. It empowers clinical researchers to identify critical temporal bottlenecks, optimize intervention timing, and fundamentally reshape how we predict the future of a patient's health.
The Corpus
The current ClaiD corpus was derived from the longitudinal electronic health records of about 300,000 patients in the Mass General Brigham system in New England, United States. This is a first instantiation of the phylophenome, and it will expand as further populations and data sources are added.
Documentation
How to read and use the ClaiD explorer
What the map shows
Every dot is a downstream condition reached from the disease you pick. Its horizontal position is the time between the two conditions, binned as 0 to 14, 15 to 30, 30 to 90, and 90 plus days. Its vertical position is model confidence that the progression is real signal rather than administrative co-occurrence. A direction control reads what follows a condition (from), what precedes it (to), or both.
The controls
1 · Pick the disease
Choose a body system, then the condition to observe, and a direction. Progressions fan out across the time axis.
2 · Model confidence
Raise the random forest and graph network thresholds, and choose whether an edge must satisfy both models or either one. Low-confidence noise falls away first.
3 · Temporal correlation
Raise the minimum on the magnitude of the tSPM correlation, and lower the maximum adjusted p. The filter uses the size of |ρ|, while the signed value stays visible on the map. The adjusted p starts at 0.05, so the default view is already restricted to multiple-testing-significant associations.
4 · Time and 5 · Genetics
Restrict to the lag windows you care about, and switch the genetic layer to all progressions, those with a measured genetic correlation, only the genetically supported, or only the measured-null. Amber means shared genetics, blue means inverse, gray means measured near zero.
The calibration trace
The trace on the right asks whether higher model confidence tracks higher genetic support. Across the corpus it rises monotonically, so the model recovers biology it was never shown. The faint line is the full-corpus reference; the bright line is your current view, with a guard when too few genetic anchors are present to calibrate.
Building a progression
Double-click any node on the map, or use Open progression network in the dig-in panel, and the builder expands full-screen. The disease you start from anchors a bold path that flows left to right. Its likely next conditions radiate off it as green branches, each labeled with the condition name and a small tag giving the time gap and the temporal correlation ρ. Click a branch to take that step; it joins the bold path and the next branches grow from there. Build A → B → C → D → E. The paler branches are the routes you did not take.
Each step can be taken at its own time bucket: the same next condition can appear as more than one branch when it is reachable at several time gaps, so A → B at one gap does not force B → C onto the same gap. A condition never appears twice in one chain, and a condition never progresses to itself. Click any committed step to back up, and export the chain as CSV.
Co-occurrence versus progression
The shortest bin, 0 to 14 days, is treated as co-occurrence rather than progression: two conditions recorded within two weeks are usually presenting together, not one leading to the other. Those links are labeled as co-occurrence and drawn dashed. Links at 15 days and beyond are progressions.
Built by the CLAI Group (Clinical Augmented Intelligence), Massachusetts General Hospital and Mass General Brigham. Code © 2026 CLAI Group.