Process Decision Program Chart (PDPC)

Process Decision Program Chart (PDPC): A Comprehensive Guide for Six Sigma Black Belt Exam

Introduction to Process Decision Program Chart (PDPC)

The Process Decision Program Chart (PDPC) is a critical quality management tool used in the Define phase of Six Sigma projects. It is a systems engineering tool that helps project teams anticipate problems and develop countermeasures before implementation. PDPC is particularly valuable for complex processes where multiple decision points and potential failures exist.

Why PDPC is Important

Risk Management: PDPC enables teams to identify potential problems and failures before they occur, reducing costly rework and project delays.

Comprehensive Planning: By mapping out decision points and potential outcomes, teams can develop more robust implementation strategies.

Resource Optimization: Understanding potential issues allows teams to allocate resources more effectively for contingency planning.

Enhanced Communication: PDPC creates a visual representation that helps all stakeholders understand the process flow and associated risks.

Quality Improvement: By proactively addressing potential failures, organizations can significantly improve process quality and reliability.

What is a Process Decision Program Chart?

A PDPC is a tree-structured diagram that maps out what could go wrong in a process and provides countermeasures for potential failures. It is designed specifically for processes involving decisions, branches, and uncertainties.

The PDPC combines elements of:

• Decision Trees: Shows multiple possible outcomes at each decision point
• Failure Mode Analysis: Identifies potential problems and their consequences
• Contingency Planning: Develops preventive and corrective actions

Key Components of PDPC

1. Main Objective: The primary goal or outcome of the process, shown at the top or left of the diagram.

2. Decision Points: Points where the process branches into different paths based on yes/no decisions or multiple options.

3. Branch Lines: Lines connecting decision points to possible outcomes, typically labeled as yes/no or success/failure.

4. Potential Problems: Identified risks or failures that could occur at each stage, often marked with a ⚠ symbol or diamond shape.

5. Countermeasures: Preventive actions or contingency plans designed to avoid or minimize the impact of potential problems.

6. Outcomes: The final results or endpoints of each path through the process.

How PDPC Works: Step-by-Step Process

Step 1: Define the Main Objective
Clearly state what the process aims to achieve. This becomes the root of your PDPC tree. For example: Launch new product successfully or Complete project within budget and timeline.

Step 2: Identify Major Process Steps
Break down the main objective into major phases or stages. These become the primary branches of your tree.

Step 3: Map Decision Points
Identify where decisions need to be made in the process. Create branches for each possible decision outcome. Use rectangular boxes or diamonds to represent decision points.

Step 4: Identify Potential Problems
For each path or decision outcome, brainstorm what could go wrong. Consider technical failures, resource constraints, external factors, and human errors. Use team knowledge and historical data to make this comprehensive.

Step 5: Develop Countermeasures
For each identified problem, develop preventive actions (to prevent the problem) and contingency plans (to minimize impact if the problem occurs). Make these specific and actionable.

Step 6: Evaluate Feasibility
Assess whether each countermeasure is practical and cost-effective. Some countermeasures may need to be refined or replaced based on resource and time constraints.

Step 7: Review and Validate
Have team members and subject matter experts review the PDPC to ensure completeness and accuracy.

PDPC Structure and Symbols

Common Symbols Used:

• Rectangle: Process steps or outcomes
• Diamond: Decision points (yes/no branches)
• Oval or Circle: Terminal nodes or final outcomes
• ⚠ or X: Potential problems or risks
• →: Process flow or countermeasure connections
• Dotted Lines: Alternative or contingency paths

PDPC Example Scenario

Objective: Implement a new customer service system

Main Process Branches:

• System Development
• Employee Training
• System Testing
• Go-Live

Example Decision Point (System Testing):
Does system pass all functional tests?
→ Yes: Proceed to Go-Live
→ No: Identify problems and countermeasures

Potential Problem (if No): Performance degradation during peak hours

Countermeasure: Conduct load testing with 150% expected capacity; optimize database queries; implement caching mechanisms

Difference Between PDPC and Other Tools

PDPC vs. Failure Mode and Effects Analysis (FMEA):
PDPC is forward-looking and focuses on prevention through mapping decision paths. FMEA analyzes existing processes to identify failure modes and their impacts. PDPC is more suitable during planning stages, while FMEA is used for detailed process analysis.

PDPC vs. Fishbone Diagram:
PDPC maps the sequence of decisions and outcomes. Fishbone diagrams analyze root causes of problems. PDPC is sequential; Fishbone is categorical.

PDPC vs. Risk Assessment Matrix:
PDPC provides detailed countermeasures and contingency plans. Risk matrices prioritize risks based on probability and impact. PDPC is more tactical; Risk matrices are more strategic.

Advantages of Using PDPC

• Proactive Problem-Solving: Identifies issues before they occur
• Systematic Approach: Ensures all decision points and paths are considered
• Enhanced Planning: Forces teams to think through contingencies
• Improved Stakeholder Buy-In: Clear visualization of risks and mitigation strategies
• Better Decision-Making: Provides data-driven insights for process improvement
• Reduced Implementation Risks: Countermeasures are developed in advance

Limitations of PDPC

• Time-Intensive: Developing a comprehensive PDPC can be time-consuming
• Complexity: For highly complex processes, PDPCs can become unwieldy and difficult to manage
• Data Dependent: Quality depends on team expertise and historical data availability
• Static Document: May need updates as conditions change

When to Use PDPC

PDPC is most effective when:

• Implementing major process changes or new systems
• Launching new products or services
• Managing complex projects with multiple decision points
• Developing contingency plans for critical processes
• Resources are available for preventive action before implementation
• Team expertise is sufficient to identify potential problems

How to Answer PDPC Questions on Six Sigma Black Belt Exams

Question Type 1: Definition and Purpose Questions

Example: What is the primary purpose of a Process Decision Program Chart?

How to Answer:
Provide a clear definition: PDPC is a planning tool that maps the sequence of processes and identifies potential problems at each decision point, along with countermeasures to prevent or mitigate those problems. Emphasize that it is forward-looking and focuses on prevention during the planning stage.

Question Type 2: Application Scenario Questions

Example: You are implementing a new manufacturing process. At which point in your project would you use a PDPC?

How to Answer:
Answer: During the Define and Plan phases, before implementation begins. Explain that PDPC helps identify and develop countermeasures for potential failures before resources are committed to implementation. This allows for better planning and risk mitigation.

Question Type 3: Comparison Questions

Example: How does PDPC differ from FMEA?

How to Answer:
Highlight key differences: PDPC is a planning tool used before implementation and focuses on decision paths and countermeasures. FMEA is an analytical tool used to examine existing or planned processes and rates failures by severity, occurrence, and detectability. PDPC is more sequential; FMEA is more categorical.

Question Type 4: Diagram Interpretation Questions

Example: In the PDPC diagram provided, identify the decision point and describe the countermeasure for the most critical risk path.

How to Answer:
Look for diamond shapes (decision points) or labeled decision statements. Trace the path to identify potential problems (marked with ⚠ or in diamond shapes). Find the associated countermeasures. Describe them specifically and explain how they prevent or mitigate the risk.

Question Type 5: Process Improvement Questions

Example: Your team has identified three potential problems in a PDPC. How would you prioritize developing countermeasures for these problems?

How to Answer:
Address prioritization criteria: Prioritize based on probability of occurrence and severity of impact. Focus on problems that are more likely to occur and would have the most significant negative impact on the process. Also consider the cost and feasibility of implementing countermeasures.

Exam Tips: Answering Questions on Process Decision Program Chart (PDPC)

Tip 1: Understand the Core Purpose

Key Point: Remember that PDPC is about proactive problem-solving and contingency planning. It is used before implementation to prevent problems, not after they occur. This distinguishes it from reactive tools like incident management systems.

Application: When answering questions, always emphasize prevention and planning aspects. If asked about using PDPC, ensure your answer reflects its use in early project phases.

Tip 2: Remember the PDPC Structure

Key Point: PDPC has four main elements in sequence:

1. Main Objective: What you want to achieve
2. Decision Points: Where choices must be made
3. Potential Problems: What could go wrong at each branch
4. Countermeasures: How to prevent or mitigate problems

Application: When analyzing a PDPC or discussing its development, reference this structure. If a question asks about completeness, check that all four elements are present.

Tip 3: Distinguish PDPC from Similar Tools

Key Point: Have clear mental distinctions between PDPC, FMEA, and Fishbone diagrams:

• PDPC: Decision paths and countermeasures
• FMEA: Failure modes and their ratings (RPN)
• Fishbone: Root cause categories

Application: If a question presents a tool or scenario, quickly identify which tool is being described or which tool would be most appropriate. Comparison questions are common on exams.

Tip 4: Focus on Countermeasures

Key Point: The real value of PDPC lies in the quality of countermeasures developed. Countermeasures should be:

• Preventive: Stop the problem from occurring
• Specific: Address the identified problem directly
• Actionable: Can be implemented within resource constraints
• Measurable: Their effectiveness can be tracked

Application: When answering questions about countermeasures, explain not just what they are but why they effectively address the problem. Vague or generic countermeasures would be poor answers.

Tip 5: Recognize Correct vs. Incorrect Statements

Watch for these common incorrect statements:

• Incorrect: PDPC should be used after process failures occur to develop recovery plans. (This is reactive, not proactive)
• Incorrect: PDPC assigns numerical risk ratings like FMEA does. (PDPC is qualitative; FMEA uses RPN)
• Incorrect: PDPC is only used in manufacturing industries. (It applies to any complex process with decisions)
• Correct: PDPC is a prevention-focused planning tool used during process design and implementation planning.

Tip 6: Practice with Realistic Scenarios

Study Approach: Use practice questions that involve realistic business scenarios. Examples include:

• New software system implementation
• Product launch process
• Process improvement rollout
• Supply chain changes
• Organizational restructuring

Application: For each scenario, mentally walk through the PDPC process: What's the objective? What decisions must be made? What problems might arise? What countermeasures are needed? This mental exercise prepares you for exam questions.

Tip 7: Know When to Use PDPC vs. When Not To

Use PDPC when:

• Process has multiple decision points (not linear)
• Complex implementation with significant risks
• Time exists to develop comprehensive countermeasures
• Team expertise is available to identify problems

Do NOT use PDPC when:

• Process is simple and linear with few decisions
• Only quick risk assessment is needed (use Risk Matrix instead)
• Root cause analysis is needed (use Fishbone instead)
• Detailed failure analysis is needed (use FMEA instead)

Tip 8: Read Multiple-Choice Questions Carefully

Strategy: In multiple-choice questions about PDPC:

• Eliminate answers that describe other tools (FMEA, Fishbone, Risk Matrix)
• Eliminate answers emphasizing after-the-fact problem-solving or root cause analysis
• Choose answers emphasizing planning, decisions, and countermeasures
• Look for answers mentioning multiple paths or contingency plans

Tip 9: For Case Study or Essay Questions

Structure Your Answer as:

1. Introduction: Define PDPC and state when/why it's appropriate for this scenario
2. Objective: Clearly state the main objective relevant to the case
3. Key Decision Points: Identify 2-3 critical decision points in the process
4. Potential Problems: List problems that could occur at each decision point
5. Countermeasures: Provide specific, actionable countermeasures for each problem
6. Conclusion: Summarize how the PDPC supports successful implementation

Tip 10: Remember the Define Phase Context

Key Point: PDPC is one of the tools used in the Define Phase of DMAIC projects. Questions may ask about the purpose of PDPC in this phase or how it fits with other Define Phase tools.

Application: Remember that in Define phase, you are:

• Clarifying project scope and objectives
• Understanding the current process
• Identifying risks and planning mitigation
• Setting baselines for comparison

PDPC supports these activities by ensuring that implementation planning is thorough and risks are managed proactively.

Tip 11: Be Specific About Symbols and Notation

If a question shows a PDPC diagram:

• Identify decision points (usually diamond shapes or decision statements)
• Identify potential problems (usually marked with ⚠ or special notation)
• Identify countermeasures (preventive or contingency actions)
• Trace the process flow from main objective through branches

If asked to describe a PDPC: Mention specific symbols if relevant to the question, but focus on the meaning (what the symbols represent) rather than just the symbols themselves.

Tip 12: Practice Time Management

For PDPC questions on the exam:

• Definition questions: 30-45 seconds maximum (these are usually straightforward)
• Scenario/application questions: 1-2 minutes (requires thinking through the logic)
• Diagram interpretation: 1-2 minutes (trace paths and identify elements)
• Comparison questions: 1-1.5 minutes (recall differences between tools)

If you're stuck on a PDPC question, mark it and move on. Don't spend excessive time on it, as other questions may be more straightforward.

Summary: PDPC Quick Reference for Exam

What: A planning and decision-mapping tool that identifies potential problems and develops countermeasures before implementation

When: During Define and Plan phases of process improvement projects

Why: To proactively prevent or mitigate risks before they impact the process

How: Map main objective → identify decision points → identify potential problems → develop countermeasures

Key Elements: Objective, Decision Points, Potential Problems, Countermeasures

Key Benefit: Prevention-focused approach that improves implementation success

Common Pitfall: Confusing with FMEA (which is analytical) or using it for root cause analysis (use Fishbone instead)