Overview
Justina’s performance scoring system provides objective, quantifiable measurements of surgical skill. The algorithm combines error detection, movement efficiency analysis, and precision metrics to generate scores from 0-100 with actionable feedback.The scoring system is penalty-based, starting from a perfect 100 and deducting points for errors and inefficiencies.
Scoring Algorithm
The core scoring logic balances multiple performance factors:Base Score
Start: 100 points (perfect performance)
Error Penalties
Deductions for surgical mistakes
Efficiency Bonus
Maintain score with optimal movement
Penalty Structure
Critical Error Penalties
Hemorrhages: -15 points each
Hemorrhages: -15 points each
Most severe penalty - indicates vascular damage
- Triggered when scalpel cuts arterial structures
- Each hemorrhage represents a life-threatening error
- Multiple hemorrhages can drastically reduce score
- 1 hemorrhage: 100 → 85 points
- 2 hemorrhages: 100 → 70 points
- 3 hemorrhages: 100 → 55 points (DEFICIENTE tier)
Tumor Touches: -8 points each
Tumor Touches: -8 points each
Moderate penalty - indicates imprecise cutting
- Counts contacts with tumor tissue during removal
- More touches = less efficient tumor extraction
- Ideal performance minimizes tissue manipulation
- 3 touches: 100 → 76 points
- 5 touches: 100 → 60 points (MEJORABLE tier)
- 10 touches: 100 → 20 points
Poor Economy of Movement: -10 points
Poor Economy of Movement: -10 points
Efficiency penalty - triggered when path is excessively indirect
- Economy > 1.5x means 50% more distance traveled than necessary
- Indicates poor surgical planning and fatigue risk
- Single flat penalty rather than graduated
- < 1.2x: Excellent efficiency
- 1.2x - 1.5x: Acceptable with room for improvement
-
1.5x: Unacceptable inefficiency (-10 penalty)
Performance Tiers
Scores are categorized into four performance levels:🌟 EXCELENTE (90-100)
Expert-level performance with minimal errors and optimal efficiency
✅ BUENO (75-89)
Proficient skill with acceptable precision and few critical errors
⚠️ MEJORABLE (60-74)
Needs improvement - multiple errors or poor efficiency
❌ DEFICIENTE (0-59)
Requires significant practice - critical errors or severe inefficiency
Factors Affecting Score
1. Hemorrhages (Critical)
Detected when the scalpel intersects arterial meshes:2. Tumor Touches (Moderate)
Counted when instrument contacts tumor fragments:3. Economy of Movement (Efficiency)
Ratio of total path length to direct distance:- 1.0x: Perfect efficiency (straight line)
- 1.2x: 20% longer than ideal (acceptable)
- 1.5x: 50% longer (penalty threshold)
- 2.0x: 100% longer (severe inefficiency)
Economy of movement is not continuously penalized - only when exceeding 1.5x threshold.
Scoring Examples
Example 1: Near-Perfect Performance
Example 2: Critical Errors
Example 3: Poor Efficiency
Supporting Metrics
While not directly affecting the score, these metrics appear in feedback:Precision vs Ideal
Percentage score based on deviation from straight-line path
Smoothness (Jerk)
Rate of acceleration change - indicator of hand steadiness
Duration
Total simulation time - context for efficiency
Average Velocity
Mean instrument speed - indicates confidence level
Precision Calculation
Feedback Generation
The scoring system generates structured markdown feedback:Conditional Recommendations
Recommendations are added based on specific performance gaps:Recommendation Triggers
Recommendation Triggers
- Hemorrhages > 0: Vascular control advice
- Economy > 1.8x: Path planning guidance
- Precision < 70%: Stability improvement suggestion
- Score < 80: General practice recommendation
Spatial Risk Analysis
The system identifies problematic surgical quadrants:- Sup-Der: Superior-Right
- Sup-Izq: Superior-Left
- Inf-Der: Inferior-Right
- Inf-Izq: Inferior-Left
Quadrant analysis helps surgeons understand spatial patterns in their errors for targeted improvement.
Score Interpretation Guidelines
What does my score mean?
What does my score mean?
90-100 (EXCELENTE)
- Maximum 1-2 tumor touches
- Zero hemorrhages
- Excellent path efficiency
- Ready for advanced procedures
- 2-3 tumor touches acceptable
- At most 1 hemorrhage
- Good efficiency with minor deviations
- Competent for standard procedures
- 4-6 tumor touches
- 1-2 hemorrhages
- Noticeable inefficiency
- Requires focused practice
- Excessive errors (7+ touches or 3+ hemorrhages)
- Very poor efficiency (>1.5x)
- Fundamental skill gaps
- Needs extensive training
Algorithmic Fairness
The scoring system is designed to be:Objective
Based purely on measurable physical metrics and event counts
Reproducible
Same movements always produce same score
Transparent
All penalty calculations visible in code
Calibrated
Penalty weights tuned to surgical severity
Future Enhancements
Planned improvements to the scoring algorithm:- Weighted Penalties: Different penalties based on tumor size/location
- Time Bonuses: Reward optimal completion times
- Difficulty Scaling: Adjust scores based on procedure complexity
- Percentile Rankings: Compare against cohort of similar experience levels
- Trend Analysis: Track improvement over multiple sessions
Next Steps
AI Analysis
Understand the complete 5-step analysis pipeline
3D Simulation
Learn about the Babylon.js simulation that generates telemetry