references/gauge-rr-study-guide.md
---
name: gauge-rr-study-guide
type: reference
parent_skill: msa-gauge-rr
author: RBraga01
version: "1.0"
status: approved
created: "2026-06-06"
last_updated: "2026-06-06"
updated_by: migmcc
reviewed_by: RBraga01
license: MIT
---
# Gauge R&R Study Conductor Guide
Operational guide for planning, executing, and documenting a crossed Gauge R&R study (10 parts × 3 appraisers × 2 trials).
Use alongside the [msa-gauge-rr](../SKILL.md) skill.
> **Scope:** This document covers how to run the physical study — part selection, randomisation, data collection, method selection, and manual calculations with a worked numeric example. For interpretation thresholds, audit criteria, and study type selection, see [msa-gauge-rr SKILL.md](../SKILL.md).
---
## 1. Pre-Study Preparation Checklist
Before any measurements are taken, confirm the following:
| Item | Requirement | Verified |
|------|-------------|---------|
| Parts selected | 10 parts spanning the full process variation range | [ ] |
| Gauge identified | Single gauge to be studied (ID, calibration cert current) | [ ] |
| Calibration current | Gauge calibration certificate valid at time of study | [ ] |
| Appraisers selected | 3 appraisers who normally perform this measurement in production | [ ] |
| Appraiser briefing | All three briefed: do not share results, do not adjust gauge | [ ] |
| Location | Study performed in production conditions (not metrology lab, unless production is the lab) | [ ] |
| Specification available | USL, LSL, and tolerance value confirmed and recorded | [ ] |
| Data sheet ready | Blank data collection sheet prepared (see Section 4) | [ ] |
| Random order generated | Measurement order randomised per appraiser per trial | [ ] |
---
## 2. Part Selection Criteria
Part selection is the single most common study error. Incorrect part selection invalidates the ndc result.
### Rules for Selecting Parts
1. **Span the full process variation range.** Parts must cover the range of values the process actually produces — from low end to high end. Do NOT select parts near the nominal or tolerance centre.
2. **Include borderline parts.** At least 2 parts should be near (but within) the specification limits.
3. **Do not cherry-pick conforming parts only.** If the process produces parts close to the limit, those must be included.
4. **Avoid selecting based on measurement value if possible.** Ideal selection: take consecutive production parts and measure them independently, then verify spread before proceeding.
5. **Parts must be stable.** Parts must not change dimension during handling between trials. For elastic or deformable parts, use fixturing.
6. **10 parts minimum.** Fewer parts reduce the statistical power of the ndc calculation.
### How to Verify Adequate Spread
After selecting parts and before starting the study, measure all 10 parts once with a reference gauge. Plot values on a number line:
- If all 10 values cluster within 20% of the tolerance range → part selection is inadequate. Select new parts.
- If values span at least 70% of the observed process range → part selection is adequate.
### Label Parts Neutrally
Code parts 1–10 (or use production serial numbers). Do not write the measured value on the part label. Appraisers must not know which parts are "near the limit."
---
## 3. Randomisation Procedure
Each appraiser must measure all 10 parts in a different random order for each trial. This is not optional — it prevents sequence bias and ensures trial-to-trial variation is captured.
### Generating the Random Order
Use a random number generator (calculator, Excel RAND(), or drawn slips):
**Example randomisation for 10 parts, 3 appraisers, 2 trials:**
| Trial | Appraiser A | Appraiser B | Appraiser C |
|-------|------------|------------|------------|
| Trial 1 | 7,2,9,1,5,3,10,6,4,8 | 3,8,1,6,10,4,2,9,5,7 | 5,1,8,3,6,10,4,7,2,9 |
| Trial 2 | 4,10,3,8,2,6,1,5,9,7 | 9,5,2,7,1,8,6,3,10,4 | 2,6,9,4,7,1,8,5,3,10 |
**Rules:**
- Appraiser A completes all 10 parts (Trial 1) before Appraiser B starts.
- Appraiser A does NOT see Appraiser B's or C's results at any time.
- Appraiser A does NOT see their own Trial 1 results before Trial 2.
- Minimum time between trials for the same appraiser: sufficient to prevent memory of previous readings (typically the time for the other appraisers to complete their trial).
- The conductor (study coordinator) records all readings. Appraisers do not self-record.
---
## 4. Data Collection Sheet Template
```
GAUGE R&R STUDY — DATA COLLECTION SHEET
=========================================
Part Number: ________________ Characteristic: ________________
Specification (USL): ________________ Specification (LSL): ________________
Tolerance (USL-LSL): ________________ Units: ________________
Gauge ID: ________________ Gauge Description: ________________
Calibration Cert #: ________________ Calibration Expiry: ________________
Study Date: ________________ Location: ________________
Conducted by: ________________
APPRAISERS
Appraiser A: ________________ Appraiser B: ________________ Appraiser C: ________________
─────────────────────────────────────────────────────────────────────────────
APPRAISER A APPRAISER B APPRAISER C
Part T1 T2 Range T1 T2 Range T1 T2 Range
─────────────────────────────────────────────────────────────────────────────
1 ____ ____ ____ ____ ____ ____ ____ ____ ____
2 ____ ____ ____ ____ ____ ____ ____ ____ ____
3 ____ ____ ____ ____ ____ ____ ____ ____ ____
4 ____ ____ ____ ____ ____ ____ ____ ____ ____
5 ____ ____ ____ ____ ____ ____ ____ ____ ____
6 ____ ____ ____ ____ ____ ____ ____ ____ ____
7 ____ ____ ____ ____ ____ ____ ____ ____ ____
8 ____ ____ ____ ____ ____ ____ ____ ____ ____
9 ____ ____ ____ ____ ____ ____ ____ ____ ____
10 ____ ____ ____ ____ ____ ____ ____ ____ ____
─────────────────────────────────────────────────────────────────────────────
X̄ᴬ ____ ____ ____ ____ ____ ____
R̄ᴬ ____ ____ ____
─────────────────────────────────────────────────────────────────────────────
PART AVERAGES (across all appraisers and trials):
Part: 1 2 3 4 5 6 7 8 9 10
Avg: ____ ____ ____ ____ ____ ____ ____ ____ ____ ____
Rp (max part avg − min part avg): ____
RANGE AVERAGES:
R̄ overall = (R̄ᴬ + R̄ᴮ + R̄ᶜ) / 3 = ____
UCLR = D₄ × R̄ = ____ (D₄ for n=2: 3.267)
APPRAISER AVERAGES:
X̄ᴬ (grand) = ____ X̄ᴮ (grand) = ____ X̄ᶜ (grand) = ____
XDIFF = max(X̄ᴬ, X̄ᴮ, X̄ᶜ) − min(X̄ᴬ, X̄ᴮ, X̄ᶜ) = ____
CALCULATIONS (see Section 6):
EV = ____ AV = ____ GRR = ____
PV = ____ TV = ____
%GRR (of TV) = ____ %GRR (of Tolerance) = ____
ndc = ____
SIGNATURES:
Study conductor: ________________ Date: ________
Quality Engineer: _______________ Date: ________
```
---
## 5. ANOVA vs. Range Method — When to Use Which
Both methods calculate EV, AV, and GRR. Choose based on the following:
| Criteria | Range Method | ANOVA Method |
|---------|-------------|-------------|
| Calculation complexity | Simple — manual calculation feasible | Complex — requires software (Minitab, Excel ANOVA) |
| Interaction term (Appraiser × Part) | Not captured | Captured — shows if appraisers rank parts differently |
| Required by AIAG MSA 4th edition | Listed as acceptable | Preferred for PPAP |
| Use when | Quick field study, training, or no software available | PPAP submission, special characteristics, customer-required |
| Result accuracy | Slightly less accurate (ignores interaction) | More accurate |
| Sample size sensitivity | Works for 2 or 3 trials | Works for 2 or 3 trials |
**Decision rule:**
- For formal PPAP submission or IATF 16949 audit purposes: use ANOVA.
- For internal qualification, quick verification, or training exercises: Range method is acceptable.
- If ANOVA reveals a significant Appraiser × Part interaction (p < 0.05): investigate whether some appraisers are measuring certain parts differently. This points to a training or fixturing issue, not just gauge imprecision.
---
## 6. Calculation Reference — Range Method
### Constants Used
| n (trials per appraiser) | d₂* | K₁ (= 1/d₂*) | D₄ |
|--------------------------|-----|--------------|-----|
| 2 | 1.128 | 0.8862 | 3.267 |
| 3 | 1.693 | 0.5908 | 2.574 |
For appraiser variation (number of appraisers = 3), use K₂ = 0.5231 directly from AIAG MSA 4th ed. Table IV. This corresponds to d₂* ≈ 1.912 (range of 3 values, 1 range calculated). Note: the value 1.693 in the EV table above is d₂* for 3 trials per appraiser — it is not the correct value for the AV calculation.
### Step-by-Step Formulas
**Step 1 — Equipment Variation (EV = Repeatability)**
EV = R̄_overall × K₁
Where:
- R̄_overall = average of all within-appraiser ranges across all parts
- K₁ = 1/d₂* for the number of trials (n = 2 → K₁ = 0.8862; n = 3 → K₁ = 0.5908)
EV is the 5.15σ spread (representing 99% of the gauge variation distribution).
**Step 2 — Appraiser Variation (AV = Reproducibility)**
AV = √[(XDIFF × K₂)² − (EV² / (n × r))]
Where:
- XDIFF = range of appraiser grand averages = max(X̄ᴬ, X̄ᴮ, X̄ᶜ) − min(X̄ᴬ, X̄ᴮ, X̄ᶜ)
- K₂ = 1/d₂* for number of appraisers (3 appraisers → K₂ = 0.5231)
- n = number of trials per appraiser
- r = number of parts
If the expression under the square root is negative, set AV = 0 (this occurs when appraiser variation is negligible relative to EV).
**Step 3 — Gauge R&R (GRR)**
GRR = √(EV² + AV²)
**Step 4 — Part Variation (PV)**
PV = Rp × K₃
Where:
- Rp = range of part averages = max(part avg) − min(part avg)
- K₃ = 1/d₂* for number of parts (10 parts → K₃ = 0.3146)
**Step 5 — Total Variation (TV)**
TV = √(GRR² + PV²)
**Step 6 — %GRR (two versions)**
%GRR (Study Variation) = (GRR / TV) × 100
%GRR (Tolerance) = (GRR / Tolerance) × 100 ← use for PPAP
**Step 7 — Number of Distinct Categories (ndc)**
ndc = 1.41 × (PV / GRR)
Round down to nearest integer.
---
## 7. Worked Numeric Example
**Study parameters:**
- Characteristic: Pin diameter, nominal 10.00 mm, tolerance ±0.15 mm → Tolerance = 0.30 mm
- 10 parts, 3 appraisers (A, B, C), 2 trials each
**Raw data (measurements in mm, deviation from nominal for readability):**
| Part | A-T1 | A-T2 | A-Range | B-T1 | B-T2 | B-Range | C-T1 | C-T2 | C-Range | Part Avg |
|------|------|------|---------|------|------|---------|------|------|---------|----------|
| 1 | 9.92 | 9.91 | 0.01 | 9.93 | 9.91 | 0.02 | 9.92 | 9.93 | 0.01 | 9.920 |
| 2 | 9.95 | 9.96 | 0.01 | 9.95 | 9.97 | 0.02 | 9.96 | 9.95 | 0.01 | 9.958 |
| 3 | 10.03 | 10.04 | 0.01 | 10.02 | 10.03 | 0.01 | 10.03 | 10.04 | 0.01 | 10.030 |
| 4 | 9.98 | 9.97 | 0.01 | 9.99 | 9.98 | 0.01 | 9.97 | 9.98 | 0.01 | 9.980 |
| 5 | 10.08 | 10.07 | 0.01 | 10.08 | 10.09 | 0.01 | 10.07 | 10.08 | 0.01 | 10.080 |
| 6 | 9.87 | 9.88 | 0.01 | 9.86 | 9.88 | 0.02 | 9.88 | 9.87 | 0.01 | 9.873 |
| 7 | 10.11 | 10.12 | 0.01 | 10.10 | 10.11 | 0.01 | 10.12 | 10.11 | 0.01 | 10.113 |
| 8 | 9.94 | 9.93 | 0.01 | 9.94 | 9.93 | 0.01 | 9.93 | 9.94 | 0.01 | 9.935 |
| 9 | 10.06 | 10.05 | 0.01 | 10.05 | 10.06 | 0.01 | 10.06 | 10.07 | 0.01 | 10.058 |
| 10 | 9.90 | 9.89 | 0.01 | 9.90 | 9.91 | 0.01 | 9.89 | 9.90 | 0.01 | 9.898 |
**Appraiser grand averages:**
- X̄ᴬ = (9.92+9.91+9.95+9.96+10.03+10.04+9.98+9.97+10.08+10.07+9.87+9.88+10.11+10.12+9.94+9.93+10.06+10.05+9.90+9.89) / 20 = **9.987**
- X̄ᴮ = **9.987**
- X̄ᶜ = **9.987**
**Average ranges:**
- R̄ᴬ = (0.01+0.01+0.01+0.01+0.01+0.01+0.01+0.01+0.01+0.01) / 10 = **0.010**
- R̄ᴮ = (0.02+0.02+0.01+0.01+0.01+0.02+0.01+0.01+0.01+0.01) / 10 = **0.013**
- R̄ᶜ = **0.010**
- R̄_overall = (0.010 + 0.013 + 0.010) / 3 = **0.011**
**UCLR check:** UCLR = 3.267 × 0.011 = 0.036. All individual ranges are below 0.036 — no outliers.
**Calculations:**
| Metric | Formula | Result |
|--------|---------|--------|
| EV | 0.011 × 0.8862 | **0.00975 mm** |
| XDIFF | max(9.987, 9.987, 9.987) − min = | **0.000 mm** |
| AV | √[(0.000 × 0.5231)² − (0.00975² / (2×10))] → negative → | **0.000 mm** |
| GRR | √(0.00975² + 0²) | **0.00975 mm** |
| Rp (part avg range) | 10.113 − 9.873 | **0.240 mm** |
| PV | 0.240 × 0.3146 | **0.07550 mm** |
| TV | √(0.00975² + 0.07550²) | **0.07612 mm** |
| %GRR (of TV) | (0.00975 / 0.07612) × 100 | **12.8%** |
| %GRR (of Tolerance) | (0.00975 / 0.30) × 100 | **3.25%** |
| ndc | 1.41 × (0.07550 / 0.00975) | **10.9 → 10** |
**Interpretation:**
- %GRR of Tolerance = 3.25% → Excellent (< 10%). Gauge is fully acceptable.
- %GRR of TV = 12.8% → Marginal when compared to study variation, but this is largely because parts are well-spread (good PV). Tolerance method is the primary criterion for PPAP.
- ndc = 10 → Well above the minimum of 5. Gauge can distinguish 10 categories of part variation.
- EV dominates GRR (AV = 0): gauge precision is the limiting factor, not appraiser technique. No training issue.
---
## 8. MSA Study Report — What to Include
The formal MSA study report submitted with PPAP or to a customer must contain:
| Section | Content |
|---------|---------|
| Study identification | Part number, characteristic, specification, tolerance, units |
| Gauge data | Gauge ID, type, resolution, calibration certificate number, expiry date |
| Study parameters | Date, location, appraisers (by ID/code — not always by name), trials, parts |
| Part selection rationale | Statement confirming parts span the full process variation range |
| Raw data table | All readings (all appraisers, all trials, all parts) |
| Range chart | Appraiser range charts with UCLR — confirm no points above UCL |
| Average chart | Part averages by appraiser — part variation must dominate |
| Results summary | EV, AV, GRR (absolute and as %), PV, TV, ndc |
| Method used | ANOVA or Range method — state which |
| Acceptance criteria applied | %GRR < 30% (tolerance method) AND ndc ≥ 5 |
| Decision | Accepted / Marginal (with justification) / Rejected |
| Signatures | Study conductor, Quality Engineer, approval authority |
| Attachments | Calibration certificate, randomisation table used |
**Do not report only %GRR of TV.** Always report both %GRR of TV and %GRR of Tolerance, and state which criterion was used for the acceptance decision.
**Flag any UCLR violations.** If any individual range exceeds UCLR = D₄ × R̄, that measurement was inconsistent. Investigate before closing the study. If the outlier is confirmed to be a special cause (mis-reading, part moved during measurement), it may be excluded and the study recalculated — document the reason.
SKILL.md
---
name: msa-gauge-rr
description: >-
Measurement System Analysis (MSA) and Gauge Repeatability & Reproducibility (Gauge R&R) — plan,
execute, and interpret an MSA study for variable or attribute measurement systems. Use when
qualifying a gauge for a new part, validating a measurement system before PPAP, interpreting
Gauge R&R results, or auditing MSA studies for adequacy. Covers AIAG MSA 4th edition.
license: MIT
metadata:
author: RBraga01
version: "1.1"
iso-9001: "7.1.5"
iatf-16949: "7.1.5.1, 7.1.5.2"
aiag-reference: "AIAG MSA 4th Edition"
domain: quality-engineering
subdomain: measurement
industries: automotive,electronics,aerospace,medical,general
status: approved
created: "2026-06-06"
last_updated: "2026-06-06"
updated_by: migmcc
reviewed_by: RBraga01
standard_edition: "AIAG MSA 4th Edition (2010)"
---
# Measurement System Analysis (MSA) / Gauge R&R
## When to use
Use this skill when:
- Qualifying a measurement system for a new part or process (PPAP requirement)
- Interpreting Gauge R&R results — is this gauge acceptable?
- Auditing a supplier's MSA study for correctness and adequacy
- Selecting the right study type for a given measurement situation
- Investigating a quality problem where measurement error may be a factor
- Responding to a customer request for MSA data on a specific characteristic
## Prerequisites
- The characteristic to be measured (product or process)
- The gauge or measurement system to be studied
- Production parts spanning the expected process variation (10 parts minimum)
- At least 2 trained appraisers who normally perform the measurement
- The specification (tolerance) for the characteristic
## Workflow
### Step 1 — Select the MSA study type
| Study type | When to use |
|-----------|-------------|
| **Gauge R&R (crossed)** | Variable data, 2–3 appraisers, each measures all parts (most common) |
| **Gauge R&R (nested)** | Variable data, parts are destroyed during measurement (e.g., tensile test) |
| **Attribute MSA** | Pass/fail, go/no-go, visual inspection — data is not a number |
| **Bias study** | Accuracy of a single gauge vs. a reference standard |
| **Linearity study** | Whether gauge accuracy is consistent across its measurement range |
| **Stability study** | Whether gauge accuracy drifts over time |
For PPAP: Crossed Gauge R&R is required for all variable gauges on special characteristics.
---
### Step 2 — Crossed Gauge R&R study procedure
**Setup:**
- Minimum **10 parts** selected to represent the full process variation range (not cherry-picked from centre of tolerance)
- Minimum **2 appraisers** (3 preferred)
- Minimum **2 trials** per appraiser per part (3 preferred)
- Parts randomly numbered and labelled — appraisers must not see each other's measurements
- Measurement conditions must match normal production conditions
**Standard study design:**
- 10 parts × 3 appraisers × 2 trials = 60 measurements
- 10 parts × 2 appraisers × 3 trials = 60 measurements
**Execution:**
1. Appraiser A measures all 10 parts in random order — record results
2. Appraiser B measures all 10 parts in random order — record results
3. Appraiser C measures all 10 parts in random order — record results
4. Repeat the cycle for trial 2 (and trial 3 if applicable)
5. Appraisers must not see their own previous results or other appraisers' results during the study
**Do NOT:**
- Allow appraisers to adjust the gauge between trials
- Use parts that are all near the nominal value (no spread)
- Record only one trial (single measurement per appraiser per part is insufficient)
---
### Step 3 — Interpret the results
#### %GRR (Gauge R&R as % of Total Variation or % of Tolerance)
| %GRR | Interpretation | Decision |
|------|---------------|---------|
| < 10% | Excellent | ✅ Gauge accepted |
| 10% – 30% | Marginal | ⚠️ May be acceptable based on application — requires engineering review and customer approval |
| > 30% | Unacceptable | ❌ Gauge not suitable — investigate and improve before use in production |
**Two calculation methods:**
- **% of Study Variation (% of TV):** GRR / Total Variation × 100 — preferred when process is in control
- **% of Tolerance:** GRR / Tolerance × 100 — use when process capability is unknown or for attribute gauging
For PPAP, %GRR < 30% (tolerance method) is the typical customer acceptance criterion. <10% is the target.
#### Number of Distinct Categories (ndc)
ndc = 1.41 × (Part Variation / GRR)
| ndc | Interpretation |
|-----|---------------|
| ≥ 5 | ✅ Gauge can distinguish adequate number of categories |
| 3 – 4 | ⚠️ Gauge can be used for go/no-go decisions only |
| 1 – 2 | ❌ Gauge cannot distinguish parts — unacceptable |
ndc ≥ 5 is required for measurement systems used on special characteristics.
#### Repeatability vs. Reproducibility
| Component | Description | Common cause |
|-----------|-------------|-------------|
| **EV (Equipment Variation / Repeatability)** | Variation when same appraiser measures same part multiple times | Gauge imprecision, worn parts, environment |
| **AV (Appraiser Variation / Reproducibility)** | Variation between different appraisers measuring the same part | Training inconsistency, measurement technique, gauge setup |
If EV > AV: investigate gauge (calibration, maintenance, resolution)
If AV > EV: investigate training, measurement procedure, gauge fixture/setup
#### When %GRR > 30% — improving the measurement system
A result >30% means the gauge is not suitable for production use. Do not proceed to PPAP — investigate and retest. Common root causes and actions:
| Root cause (high EV) | Action |
|---------------------|--------|
| Gauge resolution too coarse | Replace with a gauge of finer resolution (rule: resolution ≤ 10% of tolerance) |
| Gauge worn or damaged | Inspect, recalibrate, or replace the gauge |
| Environmental interference (vibration, temperature) | Move measurement to a stable environment; add fixture if needed |
| Inconsistent part fixturing | Design a repeatable fixture or measurement aid |
| Root cause (high AV) | Action |
|---------------------|--------|
| Measurement technique varies by appraiser | Develop a standardised measurement instruction (WI with photos/video) |
| Gauge difficult to read or position | Redesign fixture; add a datum locator; use a self-positioning gauge |
| Training gap | Retrain all appraisers using the standardised measurement WI; repeat the study |
After implementing improvements: re-run the full study. Do not accept a %GRR > 30% result with a customer waiver unless the characteristic is non-critical and the customer explicitly agrees in writing.
---
### Step 4 — Attribute MSA (pass/fail gauges)
For go/no-go gauges, visual inspection, and any pass/fail decision:
**Expanded attribute study (recommended for PPAP):**
- 50 parts spanning the full range (include parts near the accept/reject boundary)
- 3 appraisers × 3 trials per part = 450 measurements
- Calculate % agreement (within appraiser and between appraisers)
- Calculate kappa statistic (Cohen's kappa ≥ 0.9 is acceptable)
**Short method (minimum acceptable):**
- 20 parts × 2 appraisers × 2 trials
- 90% agreement within and between appraisers required
- Include borderline parts near the specification limit
---
### Step 5 — Audit an existing MSA study
When reviewing a supplier's or internal MSA, check:
- [ ] Parts selected represent the full process variation range (not all near nominal)
- [ ] Minimum 10 parts, 2 appraisers, 2 trials confirmed
- [ ] Appraisers did not see each other's or their own previous results
- [ ] %GRR result stated clearly (tolerance method or study variation method — which one?)
- [ ] ndc ≥ 5 for all special characteristics
- [ ] EV vs. AV breakdown analysed and interpreted
- [ ] %GRR < 30% (conditional: <10% preferred)
- [ ] For attribute gauges: kappa statistic calculated
- [ ] Study performed in production conditions (not in metrology lab if production measurement is on the line)
- [ ] Gauge calibration certificate current at time of study
---
## Validation criteria
An MSA study is acceptable for PPAP when:
- %GRR < 30% (tolerance method) — <10% preferred
- ndc ≥ 5
- Study conducted with production appraisers using production gauges in production conditions
- Parts selected from the full process variation range
- Results documented with part numbers, appraiser IDs, gauge ID, and calibration reference
## Common mistakes
- Parts selected near the nominal value only — artificially inflates ndc and understates GRR
- Appraiser A re-measures all parts immediately — not the same as separate trials (must separate in time)
- Using metrology lab gauges for an MSA of a production line gauge — study must use the same gauge in the same conditions
- %GRR > 30% submitted in PPAP without explanation or customer waiver
- Gauge calibration expired at time of MSA study — study is invalid
- ndc < 5 on a special characteristic — automatic PPAP finding in IATF audits
- Attribute MSA with only 2 appraisers and no borderline parts — study has no discriminating power
## Output Format
At the start of each use, ask the user:
> "How would you like to receive the output?
> **A** — Structured Markdown (formatted tables and sections, ready to copy)
> **B** — Plain tables (simplified structure for Excel or Word)
> **C** — Narrative report (flowing text for a formal document or email)
>
> Default: A."
Adapt all output sections to the chosen format. If the platform or session context already defines a format preference, skip this question.
## Changelog
| Version | Date | Author | Change |
|---------|------|--------|--------|
| 1.0 | 2026-06-06 | @RBraga01 | Initial release |
| 1.1 | 2026-06-06 | @migmcc | Added improvement guidance for %GRR > 30% — root cause table for high EV and high AV with corrective actions |