[header] How to write a medical claim appeal letter [title] Rule out simple mistakes first. [step] Sometimes a claim is denied due to a simple clerical error. These mistakes are usually the easiest to correct. 
Read through all the documentation from your insurance company, to make sure there are no obvious errors. If you find that a mistake was made by someone at your doctor's office, contact the office staff and ask them to submit corrected forms to your insurance company.