The Six Sigma Green Belt certification (ASQ CSSGB or IASSC ICGB) requires mastery of statistical tools, DMAIC methodology, and quality management concepts — across a 170-question exam that spans 4.5 hours.
The fastest candidates don't re-read textbooks in the final weeks. They review visual reference sheets — one per tool, one per phase, one per concept — until pattern recognition is automatic.
DMAIC Framework: The Core Structure
Every CSSGB exam question maps to one of five DMAIC phases. A strong cheat sheet organizes all tools by phase:
Define
Project Charter (problem statement, goal statement, scope, team) SIPOC diagram (Suppliers → Inputs → Process → Outputs → Customers) Voice of Customer (VOC) → CTQ translation Affinity diagrams, stakeholder analysis Measure
Process mapping (swimlane, VSM) Data collection plan (continuous vs. discrete, operational definitions) Measurement System Analysis (MSA/Gage R&R) Basic statistics: mean, median, mode, range, standard deviation Process capability: Cp, Cpk, Pp, Ppk, sigma level, DPMO Analyze
Root cause analysis: fishbone (Ishikawa), 5 Whys, fault tree Hypothesis testing: t-test, ANOVA, chi-square, F-test Correlation and regression (r², p-value interpretation) Pareto analysis (80/20 rule) Improve
DOE (Design of Experiments): full factorial, fractional factorial Lean tools: 5S, kaizen, waste elimination (8 wastes of lean) Solution selection matrix, pilot planning Control
Control charts: X̄-R, X̄-s, Individuals (IMR), p, np, c, u Control plan, reaction plan Statistical Process Control (SPC) interpretation rules Mistake proofing (poka-yoke) Statistical Tools: Where Most Candidates Fail
The CSSGB exam is notably heavy on statistics. Key areas:
Hypothesis Testing Selection:
Comparing 2 means → 2-sample t-test Comparing 3+ means → One-way ANOVA Comparing proportions → Chi-square or 2-proportion z-test Comparing variances → F-test (Levene's) Process Capability:
Cp = (USL - LSL) / (6σ) — measures spread Cpk = min[(USL - X̄), (X̄ - LSL)] / (3σ) — measures centering Cpk < 1.0 = incapable process Cpk > 1.33 = capable (common industrial threshold) 6 Sigma = 3.4 DPMO = Cpk ≈ 2.0 Control Chart Selection:
Continuous data, subgroups → X̄-R or X̄-s Continuous data, individuals → IMR (I-MR) Attribute (defectives), variable n → p chart Attribute (defectives), constant n → np chart Attribute (defects per unit) → u chart Attribute (defects), constant n → c chart Free Six Sigma Green Belt Study Map Sample
We've built 20 visual Six Sigma Green Belt study maps covering every DMAIC phase:
DMAIC overview (complete phase map) Control charts selection guide Hypothesis testing decision tree Process capability (Cp, Cpk, Pp, Ppk) Measurement System Analysis (Gage R&R) Statistical tools reference Lean tools and 8 wastes Root cause analysis methods Quality tools (Pareto, fishbone, scatter) Voice of Customer (VOC) to CTQ → Get your free Six Sigma Green Belt study map
StudyMaps creates visual study maps for professional certifications. CSSGB, NCLEX-RN, CCNA 200-301, FE Civil. View Six Sigma maps →
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