🎯 Target Failure Rate

🎯 Target Failure Rate

📌 Definition

The target failure rate (*p₀*) in cusum_analysis is a predefined acceptable rate of failure for a procedure. It acts as a baseline against which a trainee’s performance is compared. Deviations from this rate help determine learning progression or performance issues.

It must be set realistically based on clinical standards, published data, or institutional benchmarks.

🧠 How to Choose a Target Failure Rate

Factors to consider:

Literature-based complication rates
Internal quality data from experienced clinicians
Complexity of the procedure
Training stage (novice vs expert-level target)

📊 Examples

Procedure	Target Failure Rate (p₀)	Notes
————————————-	——————————-	———–
lumbar_puncture	10–20%	Includes traumatic taps or supervisor takeover
central_line_insertion	5–10%	Includes failed placement, arterial puncture
intubation (1st pass)	10–20%	Setting-dependent: OR vs ED vs ICU
ube_lumbar_discectomy	10–15%	Includes incomplete decompression or conversions
laparoscopic_cholecystectomy	5%	Conversion to open, bile leak, etc.

🧪 In the CUSUM Formula

\[ S_i = S_{i-1} + (X_i - p₀) \] Where:

Xᵢ = 1 for failure, 0 for success
p₀ = target failure rate (e.g., 0.20 = 20%)
Sᵢ = cumulative sum at procedure *i*

⚠️ Pitfalls in Choosing p₀

Setting *p₀* too low = premature labeling of underperformance
Setting *p₀* too high = failure to detect real learning issues
It should reflect a balance between ideal and realistic

Table of Contents

🎯 Target Failure Rate

📌 Definition

🧠 How to Choose a Target Failure Rate

📊 Examples

🧪 In the CUSUM Formula

⚠️ Pitfalls in Choosing p₀