Reference

Health-tech engineering glossary

Plain-language definitions of the standards, laws, and architecture patterns behind Indian digital health and multi-tenant platforms — written from production deployment experience, not documentation alone.

Summary

ABDM is India's national digital health network built on ABHA identifiers, HIP/HIU data exchange, and consent artifacts; records move as FHIR R4 JSON bundles. FEFO plus double-entry ledgers keep biological medicine stock accurate; Row-Level Security isolates SaaS tenants in one database; and the DPDP Act 2023 makes platforms data fiduciaries who must reconcile erasure with medical retention.

ABDM (Ayushman Bharat Digital Mission)#

India's national digital health network, stewarded by the National Health Authority. It connects hospitals, labs, and apps through a central gateway for identity (ABHA), consent, and metadata routing — while clinical records travel point-to-point between providers, never through the centre.

ABDM Milestones (M1, M2, M3)#

The three ABDM integration stages: M1 — ABHA number creation and verification; M2 — linking care contexts (visits, prescriptions, reports) to a patient's ABHA address; M3 — consent-driven health data exchange between HIP and HIU using FHIR R4 bundles and ECDH encryption.

Related: M1/M2/M3 walkthrough

ABHA (Ayushman Bharat Health Account)#

A 14-digit health identifier with an address like user@abdm, created via Aadhaar or mobile OTP. ABHA links a patient's health records across providers; it stores consent and linking metadata, not the records themselves.

HIP and HIU#

HIP (Health Information Provider) is any system that holds and shares patient clinical data — a hospital EMR or lab system. HIU (Health Information User) is any authorized system that requests that data with patient consent, such as a teleconsultation app or specialist portal.

FHIR R4 (Fast Healthcare Interoperability Resources, Release 4)#

The HL7 standard for exchanging health data as structured JSON resources (Patient, Composition, DiagnosticReport). Under ABDM, records must be packaged as FHIR R4 document bundles following the NDHM implementation profiles published by NRCeS.

Care Context#

A linkable unit of healthcare — one visit, prescription, diagnostic report, or discharge summary. Linking a care context to a patient's ABHA address is what makes that record discoverable through consent-driven ABDM data requests.

FEFO (First-Expired, First-Out)#

An inventory allocation policy for perishable goods: always dispense the batch expiring soonest first. For blood-factor concentrates and vaccines, FEFO enforced by database row locks (SELECT ... FOR UPDATE SKIP LOCKED) prevents both expired waste and emergency stock-outs.

Cold Chain#

The temperature-controlled supply chain required for biological medicines such as clotting factors and vaccines. In software terms: continuous temperature telemetry, batch-level expiry tracking, and alerts before excursions or expiry, not after.

Row-Level Security (RLS)#

A PostgreSQL feature that filters rows per database session using a policy (e.g. tenant_id must match the session's tenant). Shared-schema multi-tenant SaaS uses RLS to isolate customers' data in one table set — one migration, normal connection pooling, per-row isolation.

Related: schemas vs RLS decision guide

Schema-per-Tenant#

A multi-tenancy model giving each customer its own PostgreSQL schema. Strong physical isolation and easy per-tenant restores, but hundreds of schemas make every migration, connection pool, and backup exponentially harder — best suited to fewer than ~100 high-compliance tenants.

DPDP Act 2023 (Digital Personal Data Protection Act)#

India's data-protection law. For health platforms the operative tension is the patient's Right to Erasure versus statutory medical record retention — resolved architecturally by scrubbing identifiers while retaining anonymized clinical fact, with consent state machines and immutable audit logs.

Data Fiduciary#

Under the DPDP Act, the entity that determines how personal data is processed and is accountable for it. Health platforms are data fiduciaries for patient data, which drives obligations: purpose limitation, consent management, security safeguards, and breach reporting.

Double-Entry Inventory Ledger#

Applying financial accounting to physical stock: every movement is a balanced debit/credit journal entry (e.g. Dispensed −1 from Ward A, +1 to Patient X). On-hand quantity is always a derived SUM, so stock can never silently drift — phantom stock becomes mathematically impossible.

Offline-Tolerant Software#

Architecture where the local device (SQLite/IndexedDB) is the primary write path and the server is a sync target: clinical actions commit locally in milliseconds and replicate asynchronously, with domain-specific conflict resolution — so hospital counters keep working through network and power failures.