===== Outcome Target =====

Defining a clear and realistic **outcome target** is fundamental for the validity of any CUSUM analysis. The target represents the acceptable performance level or complication rate that serves as a benchmark for comparison.

In this analysis, we selected a **target complication rate of 10% (k = 0.1)** for ICP monitor placements, based on:

  * Published literature on acceptable complication rates for external ventricular drains and ICP bolts.
  * Internal quality control data from our institution.
  * Consensus among experienced neurosurgeons in the department.

The outcome target must strike a balance between being **challenging enough to drive improvement** and **realistic enough to reflect clinical complexity**.

Targets may vary depending on:
  * **Procedure type** (e.g., tumor resection vs. shunt placement)
  * **Patient population** (e.g., pediatric vs. adult)
  * **Institutional context** (e.g., high-volume center vs. low-resource setting)

Outcome targets can also be dynamic. As surgical teams gain experience or new techniques are adopted, the acceptable rate may be adjusted downward to reflect higher expected standards.