====== Expert Consensus Opinion  ======
 

An **[[expert]] [[consensus]] [[opinion]]** is a collective judgment, recommendation, or guideline formulated by a group of experts in a particular field when high-quality empirical evidence (such as randomized controlled trials or systematic reviews) is lacking, inconsistent, or insufficient to guide clinical practice.  

### **Key Characteristics:**  
1. **Based on Expert Judgment** – Developed by specialists with extensive experience in the field.  
2. **Used When Evidence is Limited** – Often applied in emerging or niche medical areas where robust data is unavailable.  
3. **Formal or Informal Methodology** – Can be established through **Delphi method**, panel discussions, or systematic review of available data.  
4. **Not a Primary Research Study** – Does not present new experimental data but synthesizes existing knowledge and expert perspectives.  
5. **Can Influence Guidelines** – Helps in shaping clinical guidelines, policies, and best practices.  

### **Examples of Expert Consensus Opinions in Medicine:**  
- The American Society for Stereotactic and Functional Neurosurgery’s statement on **MRI-guided Laser Interstitial Thermal Therapy (MRgLITT)** for epilepsy.  
- Consensus statements on surgical approaches in neurosurgery, oncology, or rare diseases.  
- Guidelines on ethical issues, surgical indications, or the use of novel medical technologies.  

### **Distinction from Other Study Types:**  
- **Different from Systematic Reviews or Meta-Analyses**: Does not follow a strict evidence-based approach with predefined inclusion/exclusion criteria.  
- **Different from Randomized Controlled Trials (RCTs)**: Does not test a hypothesis through direct experimentation.  
- **Different from Narrative Reviews**: While both summarize knowledge, an expert consensus is typically the **official position** of a recognized organization or expert panel.  

Would you like examples of specific expert consensus documents in neurosurgery or another field?