Design After Action: A Key Diagnostic Process for Project Improvement

PMBOK v8 Definition

The Diagnostic process is a component of after-action reviews, which are structured reviews conducted to analyze what happened, why it happened, and how it can be done better. According to PMBOK v8, after-action reviews include a diagnostic process that examines project performance to identify root causes of successes and failures, enabling teams to capture lessons learned and improve future project outcomes.

Why It Matters for the Exam

The Diagnostic process within after-action reviews appears frequently on the PMI exam in questions about lessons learned, continuous improvement, and project closure activities. It is tested in situational questions where the project manager needs to analyze performance data, identify root causes, and implement corrective actions. Understanding this concept helps you distinguish between simple data collection and meaningful analysis that drives project improvement.

Key Points to Remember (for the exam)

• Core Purpose: The diagnostic process identifies why performance deviations occurred, not just what happened
• Timing: After-action reviews with diagnostic processes occur at project phase ends and project closure
• Root Cause Focus: The diagnostic process uses root cause analysis to determine underlying factors behind project outcomes
• Input Sources: Project documents, performance data, and stakeholder feedback are analyzed during the diagnostic process
• Output Value: Diagnostic findings feed into lessons learned documentation and organizational process assets
• Key Distinction: Diagnostic process is analytical (finding causes), not just descriptive (stating facts)
• Common Confusion: The diagnostic process is often confused with simple data collection—diagnosis requires interpretation and analysis

Typical PMI Exam Example

A project completed under budget but behind schedule. During the after-action review, the project team analyzes schedule data and identifies that three critical path tasks were delayed due to resource unavailability. The team uses the diagnostic process to determine that the root cause was inadequate resource planning during the Develop Schedule process. This diagnosis leads to updated resource estimation procedures for future projects.

PMI Exam Traps

• Trap: Thinking the diagnostic process is the same as an audit

• Reality: Audits verify compliance; the diagnostic process analyzes causes of performance

• Trap: Confusing the diagnostic process with the entire after-action review

• Reality: The diagnostic process is one component of after-action reviews, not the entire review

• Trap: Believing diagnosis only happens at project closure

• Reality: Diagnostic processes occur throughout the project lifecycle during phase-end reviews

• Trap: Assuming diagnosis focuses only on problems

• Reality: The diagnostic process examines both successes and failures to identify what worked well

Important PMI Connections

Quick Review Questions

1. What is the primary purpose of the diagnostic process in after-action reviews?

2. During which project phases should the diagnostic process be conducted?

3. What is the key difference between the diagnostic process and simple performance data collection?

4. How do diagnostic findings contribute to organizational process assets?

5. A project team identifies that a task was delayed. What additional step must the diagnostic process perform?

PMBOK v8 Reference

Section 145 – Diagnostic process, in after-action reviews