Multi-Diagnosis & CPT Code Selection for Insurance Billing
My Role
End-to-end UX design
Workflow modeling
Competitive & standards research
Iterative prototyping
Billing team collaboration and validation
DESCRIPTION
During a patient visit, when insurance is selected as the payment method, medical practices are required to submit claims with accurate diagnoses and corresponding CPT codes. Many treatments address multiple diagnoses and require multiple CPT codes, often with different units and modifiers.
The existing payment flow did not support this real-world complexity, creating billing errors, rework, and claim rejections.
PROBLEM
The current system assumed a one-to-one relationship between:
Diagnosis → CPT code
Real-World Example
If a provider treats 15 moles, billing requires:
17000 → first lesion
17003 → lesions 2–14 (with units)
17004 → 15+ lesions
Each CPT may require:
Different modifiers
Specific units
Association to one or more diagnoses
The system simply couldn’t handle this logic without error.
Key Limitations
Only one diagnosis could be selected per visit
Each diagnosis could support only one CPT
CPTs could not be mapped across multiple diagnoses
Complex treatments required manual workarounds outside the system
GOAL
Support multiple diagnoses per visit
Allow multiple CPTs per diagnosis
Preserve billing accuracy and compliance (CMS-1500)
Reduce cognitive load for front-office and billing staff
Align UI with real-world medical billing workflows
RESEARCH
To ground the design in medical and billing standards, I focused on:
1. Standards Review
Studied how diagnoses and CPTs are entered in the CMS-1500 claim form
Mapped relationships between diagnoses, CPTs, modifiers, and units
2. Competitive & Comparative Analysis
Reviewed workflows from several medical billing and EHR systems
Analyzed how other platforms handle:
Multi-diagnosis treatments
CPT grouping
Diagnosis-to-code mapping
3. Internal Stakeholder Interviews
Partnered with internal billing specialists
Validated edge cases, common errors, and mental models
Identified where current workflows caused confusion or rework
SOLUTION
Redesigned Payment & Billing Flow
I redesigned the existing payment screen to better reflect real-world medical practice while keeping the interface intuitive and efficient.
Option A
Option C
Option B
KEY DESIGN DECISIONS
1. Diagnosis Pre-Selection
Users can select all applicable diagnoses upfront for a treatment
Diagnoses persist across CPT selection
2. Flexible CPT Assignment
Users can add multiple CPT codes
Each CPT allows:
Diagnosis association via dropdown (pre-populated)
Modifiers
Units
3. Clear Hierarchy & Mapping
Visual structure makes it clear:
Which CPTs belong to which diagnoses
How units and modifiers apply
Reduces errors without adding complexity
4. Iterative Validation
Explored multiple design patterns for:
CPT grouping
Diagnosis assignment
Error prevention
FINAL DESIGN
OUTCOME
Enabled accurate billing for multi-diagnosis treatments
Reduced manual workarounds and billing errors
Improved claim readiness and confidence for staff
Aligned system behavior with CMS standards and real clinical workflows