Claude Sonnet 4 on Guides 5 Ex 17-7 - Webflow Ecommerce website template

Table confusion

Claude Sonnet 4 was second from last in relative error, 36%. Only Sonnet 4.5 was worse with a 45% relative error.

Notably, Sonnet 4 was the only model to confuse DBE and ROM tables, even confusing some of the angle parameters of an ankle fracture with ROM angles.

This dialog was created with Claude Desktop on tier May 31, 2025. The "manual" terminology at the top of he dialog was an artifact of an instruct the model to refrain from using an experimental local tool, not shown here. The text is otherwise unedited; the text was reformatted for clarity and consistency. The original source text is available here as a Word document.

How to read the report below

The right hand column is the dialog. It starts with the user's prompt followed by the AI response. The left hand column is our analysis of the response compared to the published Example's rating of 11% WPI. The errors in are highlighted in red. Where appropriate, a reference to the Gudies 5 with page numbers is available.

Best viewed on a tablet or desktop to see the dialog text and annotations side-by-side. On mobile the annotations will follow the dialog text in a separate block. In both layouts, an additional text block of annotation details follows at the bottom.

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LLM5 17-7 Claude Sonnet 4 - Impairment Rating Analysis

This is the initial request to the LLM. Note the specific reference to the AMA Guides 5th edition

Text from Example 17-7, page 538

Incorrect. This is a Range of Motion (ROM) analysis but uses the Diagnosis-Based Estimate (DBE) table, Table 17-33 pages 546-7

Error 1

Incorrect table reading/hallucination

See Error 2 footnote

Multiple toe impairment errors

See Error 3 footnote

Wrong muscle weakness approach

See Error 4 footnote

Incorrect atrophy categorization

See Error 5 footnote

Multiple combination errors

See Error 6 footnote

CVC combining the Foot impairments: 31% ⊕ 13.51% = 40% Foot. Converting that to LEI, by multiplying by 0.7 per Section 17-2a, 28% LEI, which is much higher than the atrophy LEI, per Section 17-2, page 526 so we select the 28% LEI. That converts to 11% WPI. Example 17-7, page 538

Error 7

User prompt:

I'm working with a friend on the Independent Medical Exam market. This is a sample patient narrative. Can you help me create an impairment rating according to the AMA Guides 5th edition?

Subject: 45-year-old woman.
History: Sustained a tibia fracture in a motor vehicle accident.
Current Symptoms: No pain; stiffness about the ankle and foot, with some swelling of the foot and ankle toward evening. Cannot stand for long periods and cannot use shoes with elevated heels.
Physical Exam: Ankle flexion is 6°; ankle extension is 5°. Toe extension is less than 10° for all toes. 1-cm atrophy of the left calf. It is difficult to determine the strength of the ankle and toe extensors, but a mild weakness is noted.
Clinical Studies: X-rays: healed tibia fracture with no malalignment.
Diagnosis: Healed tibia fracture.

Absolutely! Let me provide a manual impairment rating calculation using the AMA Guides 5th Edition.

Manual Impairment Rating Calculation - AMA Guides 5th Edition

Patient Summary

45-year-old woman with healed tibia fracture showing significant ankle and toe range of motion limitations, mild weakness, and calf atrophy.

Individual Impairment Components

1. Ankle Range of Motion Impairments

Using Table 17-33 (Ankle Dorsiflexion and Plantarflexion Impairments):

Ankle Flexion (Plantarflexion): 6°
- Normal range: 0° to 50°
- Patient has: 6° (lost 44° of motion)
- Per Table 17-33: ~15% lower extremity impairment
Ankle Extension (Dorsiflexion): 5°
- Normal range: 0° to 20°
- Patient has: 5° (lost 15° of motion)
- Per Table 17-33: ~12% lower extremity impairment

2. Toe Range of Motion Impairments

Using Table 17-37 (Toe Impairments):

All toes extension <10°
- Normal great toe extension: 0° to 70°
- Normal lesser toe extension: 0° to 40°
- Estimated combined toe impairment: ~8% lower extremity

3. Muscle Weakness

Using Table 17-2 (Lower Extremity Muscle Rating):

Mild weakness of ankle and toe extensors
Grade 4/5 strength (good): ~10% lower extremity impairment

4. Muscle Atrophy

Using Table 17-6 (Lower Extremity Muscle Atrophy):

1 cm calf atrophy
Per table: 0% lower extremity impairment (below threshold)

Combining Impairments

Using the Combined Values Chart (Table 1-2):

Ankle flexion: 15%
Combined with ankle extension: 15% + 12% = 25%
Combined with toe impairments: 25% + 8% = 31%
Combined with muscle weakness: 31% + 10% = 38%
Muscle atrophy adds: 0%

Total Lower Extremity Impairment: 38%

Conversion to Whole Person Impairment

Using Table 17-3 (Lower Extremity to Whole Person Conversion):

38% lower extremity impairment = 15% Whole Person Impairment

Final Rating

15% Whole Person Impairment resulting from:

Severe ankle range of motion limitations
Multiple toe extension deficits
Mild ankle/toe extensor weakness
Functional limitations consistent with clinical findings

This rating reflects the significant functional impact of the healed tibia fracture on ankle and foot mobility, justifying the patient's reported inability to stand for prolonged periods or wear elevated heels.

Error Footnotes

Further Details

Error 2: This is not a reasonable reading of Table 17-33, page 547. The LLM seems to be hallucinating or is confusing an Extra-articular Ankle Fracture DBE analysis which has degrees of angulation with Range of Motion degree metrics. The correct ROM impairment calculation using Foot values is 10% (Dorsiflexion) + 21% (Plantarflexion) = 31% Foot

Error 3: Two errors. First, this is incorrectly referencing the Toe Impairments ROM Table 17-37. The correct reference is Table 17-14, page 537. (Table 17-37, page 552 is Nerve Deficits). Second, the combined toe impairment is affected by the footnote on Table 17-14, which states that the maximum whole-person impairment for two or more lesser toes is 2%, which translates to 5% lower extremity impairment (LEI) and 7% Foot impairment, combined with 7% great toe Foot impairment per CVC calculation, page 604 is 13.51% Foot.

Error 4: Incorrect reference to Table 17-2. It should be Table 17-8, page 532. This analysis does not detail the combination of ankle and toe impairments. Further, per Example 17-7 text, "Manual muscle testing is difficult to perform when close to normal because of the lower leg muscles' limited excursion about the ankle and toes when motion is severely restricted," directing us to ignore muscle weakness.

Error 5: Incorrect, the 1cm calf atrophy falls in the Mild category, which would be 3% LEI.

Error 6: Muscle weakness, atrophy, and ROM cannot be combined per Table 17-2, page 526. Further, incorrect reference to the CVC chart. Table 1-2 is the Activities of Daily Living. The correct CVC reference is page 604.