Analyzed the reliability of depression screening and follow-up processes in a primary care setting, focusing on structural workflow failure points rather than clinical outcomes alone.

Context

CMS quality measures require routine depression screening (PHQ-2 followed by PHQ-9 when indicated) and documented follow-up plans. In practice, completion rates and follow-up adherence vary due to workflow complexity rather than clinical disagreement.

The objective of this project was to analyze the screening process as a system and identify where reliability degrades.

System Mapping

The full workflow was decomposed from patient intake through:

  • Intake documentation
  • PHQ-2 administration
  • PHQ-9 escalation logic
  • Provider review
  • Follow-up documentation
  • Referral and care coordination

Each transition point was analyzed for task ownership, dependency, and failure sensitivity.

Hierarchical Task Analysis (HTA)

A formal HTA was constructed to:

  • Identify nested task dependencies
  • Clarify conditional branching (e.g., PHQ-2 positive → PHQ-9 required)
  • Surface hidden coordination steps
  • Reveal where omission errors were most likely

The HTA made explicit where screening success depends on cross-role coordination rather than a single actor.

Reliability Risks Identified

Structural risks included:

  • Task ambiguity between intake staff and providers
  • Conditional escalation steps dependent on manual interpretation
  • EHR interface friction
  • Documentation lag affecting quality reporting

The key insight was that screening compliance is less a knowledge problem and more a process integrity problem.

Design Implications

Improving outcomes would likely require:

  • Standardized task sequencing
  • Clear ownership assignment
  • Interface simplification
  • Reduced reliance on memory-dependent transitions

The analysis reframed depression screening as a workflow reliability issue rather than a purely clinical adherence issue.