Denials can have different root causes, depending on the payer, the service, the patient, and the provider. Common causes include coding errors, missing or incomplete information, eligibility issues, and policy changes. To avoid coding errors, you should use accurate and updated coding systems such as ICD-10, CPT, and HCPCS. Furthermore, you should train coders and billers on the latest coding guidelines and standards, as well as use software tools to check and validate codes before submitting claims. Missing or incomplete information can be prevented by verifying and collecting all necessary information from the patient at the point of service. Additionally, ensure that this information is correctly entered into your electronic health record (EHR) system. To prevent eligibility issues, verify insurance coverage and benefits before providing service. Also, obtain any prior authorization or pre-certification that is needed and educate patients on their co-pays, deductibles, and coinsurance. Lastly, stay updated on the payer's policies and contracts to avoid policy changes. Communicate with the payer regularly to resolve any disputes or discrepancies as soon as possible.