Prior Auth Integration Lab

Interview prep

Talking Points

Concise ways to connect existing API/FHIR integration experience to HL7 v2, X12 278, prior authorization workflows, and customer-facing debugging.

I can translate business workflows into resource/API contracts, auth requirements, request/response examples, and test cases.
FHIR experience gives me a strong mental model for normalized healthcare data even when the source format is HL7 v2 or EDI.
I am comfortable debugging REST calls, auth failures, file-transfer issues, and payload-level data-quality problems.

HL7 v2 and X12 look unfamiliar at first, but they are structured payloads with delimiters, segments, fields/elements, identifiers, and implementation-specific rules.
My approach is to identify the envelope/control metadata, locate the patient/provider/payer/request sections, then map them to an internal model.
Companion guides and implementation guides are the source of truth for required loops, qualifiers, code sets, and edge cases.

I preserve the raw payload, parsed tree, normalized output, validation errors, warnings, and correlation IDs so teams can reproduce issues.
I separate parser failures from business-validation failures and routing/configuration failures.
I write small negative fixtures for missing identifiers, invalid dates, payer mismatches, unsupported codes, and duplicate submissions.

I ask about source system ownership, transport, authentication, message version, required fields, volume, SLAs, retries, monitoring, and support contacts.
I request representative happy-path and error-path payloads early, then turn them into mapping docs and test cases.
I confirm who owns clinical, operational, and payer-specific mapping decisions before implementation starts.

I document source field, target field, transformation, validation rule, default behavior, and example values for every important mapping.
I call out conditional logic, payer-specific overrides, identifier precedence, timezone/date handling, and code-system assumptions.
I use customer-readable error messages for operational teams and technical logs for engineering escalation.

I would describe 278R as both a request and response workflow: submit service-review data, capture payer status/authorization identifiers, and reconcile that result back to the source workflow.
For 275 attachments, I would focus on correlation IDs, control numbers, document metadata, encryption, acknowledgement handling, and payer-specific attachment rules.
I would avoid guessing loop requirements and instead validate 2000E, 2010EA, 2010EB, service type codes, and response segments against the implementation and companion guides.

For VPN and mTLS setup, I gather IPs, ports, DNS, certificate chains, cipher expectations, renewal owners, and test windows before implementation starts.
I troubleshoot connectivity in layers: DNS, route, firewall, VPN tunnel, TCP reachability, TLS handshake, authentication, then application payload.
I keep PHI out of packet captures and logs unless security policy explicitly permits a controlled diagnostic capture.

I turn implementation examples into Postman/Newman smoke tests and negative fixtures for schema, auth, timeout, duplicate, and payer-routing failures.
I use SQL audit patterns such as CTEs and window functions to find duplicate transactions, missing required fields, and source-vs-target mismatches.
I define alert thresholds for volume drops, payer timeouts, validation spikes, SFTP acknowledgement latency, and certificate expiration.

I start with the implementation guide concepts, then compare payer companion-guide deviations loop by loop and qualifier by qualifier.
I build a traceability matrix from guide requirements to parser/validator tests and sample payloads.
I would pair with an EDI expert or payer implementation contact for ambiguous loops instead of guessing in production.