Evaluation of a surveillance system

Steps of an evaluation

1. Plan the evaluation
   1. Understand the trigger
   2. Engage stakeholders
   3. Decide on attributes
2. Perform the evaluation
   1. Start with a evaluation protocol
   2. Look at each attribute in its own way
3. Propose an action plan

Typical triggers (1a)

• Missed outbreak
• Increased disease importance
• Occurrence of new public health event
• Cost saving
• Requirement to evaluate (IHR)
• New technology

Engage the stakeholders (1b)

• Surveillance is a group effort
• Not like a science project

Choose attributes (1c)

• Depends on the trigger
• Many attributes are costly

Balance of attributes (1c)

Evaluation protocol (2a)

• Its similar to a study protocol
• Important for coordination
• Important part: Describe the system

Evaluate attributes (2b)

• Sensitivity: Get gold standard
• External completness: Capture-Recapture
• Internal completeness: Data analysis
• Timeliness: Data analysis
• Usefulness: Survey

Propose an action plan (3)

• An evaluation is objective oriented
• It should focus on improving the system