1. Do you provide protocols on sample preparation to your users?   
2. Do you give them additional tips and tell them about common mistakes to avoid? 
3. Do you know what controls the user include?    
4. Do you know how the user prepares the samples? 
5. Is the sample quality checked before data acquisition?  
6. If you are aware of poor sample quality, do you allow the user to proceed?  
7. If you are aware of poor sample quality, do you tell the user about the potential consequences and drawbacks of proceeding with them?