General Practice Denial Patterns
General practice experiences denial rates of 5% to 10%, which is on the higher end of the medical specialty range. The high denial rate reflects the breadth of services provided and the corresponding breadth of payer rules that apply. A cardiologist deals primarily with cardiology-specific payer rules. A general practitioner must navigate E/M coding rules, preventive care coverage rules, minor procedure billing rules, chronic care management requirements, and diagnostic testing medical necessity criteria across every visit type. The volume of rules creates more opportunities for error.
Denial Reason 1: E/M Level Downcoding (CARC 45)
CARC 45 (charge exceeds fee schedule or maximum allowable) appears when the payer downcodes the E/M level. Some payers routinely downcode 99215 to 99214 or 99214 to 99213 when the documentation does not clearly support the higher level. Under the 2021 guidelines, the documentation must explicitly support the MDM complexity or time claimed. Payers audit E/M levels by reviewing the number of problems addressed, data ordered or reviewed, and risk of management. If the note says “discussed medication options” but does not specify which medications or the risk profile, the payer may downcode. Prevent this by documenting MDM elements explicitly and specifically.
Denial Reason 2: Missing Modifier 25 (CARC 97)
When a general practitioner performs a minor procedure (I&D, skin biopsy, lesion removal, joint injection) during an office visit, the E/M visit requires modifier 25 (significant, separately identifiable evaluation and management service). Without modifier 25, the payer bundles the E/M into the procedure and pays only the procedure fee. CARC 97 (payment adjusted per bundling rules) appears on the E/M line. This denial is entirely preventable. Configure the practice management system to automatically flag claims where an E/M and a procedure are billed on the same date without modifier 25.
Denial Reason 3: Duplicate Visit Denials (CARC 18)
CARC 18 (exact duplicate claim) triggers when two E/M visits are billed for the same patient on the same date. In general practice, this commonly occurs when a patient is seen in the morning for one problem and returns in the afternoon for an unrelated problem. The second visit requires modifier 76 (repeat procedure by same physician) or modifier 25, depending on whether the services are distinct. Without the appropriate modifier, the second claim appears as a duplicate of the first and is denied. Some payers do not allow two E/M visits on the same date regardless of modifiers, so verify payer policy before scheduling same-day return visits.
Denial Reason 4: Medical Necessity for Lab and Imaging (CARC 50)
General practitioners order a wide range of diagnostic tests (blood work, urinalysis, X-rays, EKGs) that require medical necessity documentation. CARC 50 (not deemed medically necessary) appears when the ICD-10 code does not support the test ordered. Common examples: lipid panel ordered with an annual physical diagnosis code (the preventive visit code should be linked to the lipid panel only if the patient meets screening criteria), TSH ordered without a thyroid disorder diagnosis, and chest X-ray ordered without respiratory symptoms. Link diagnostic tests to the specific symptom or condition diagnosis, not the visit-level diagnosis.
Denial Reason 5: Coordination of Benefits (CARC 22)
CARC 22 (payment adjusted because another payer is primary) is common in general practice because patients frequently have multiple insurance plans (Medicare plus supplemental, two employer plans for dual-income households, Medicaid as secondary). When the billing system submits to the wrong primary payer, the claim is denied with CARC 22. This denial requires resubmission to the correct primary payer. Prevent it by verifying the coordination of benefits (COB) order during registration and confirming which plan is primary before every visit.
Preventing General Practice Denials
Five automated checks prevent the majority of general practice denials: eligibility verification with COB confirmation before every visit, automatic modifier 25 flagging when E/M and procedure codes appear on the same claim, E/M level validation against documented MDM elements, diagnosis-to-procedure medical necessity crosswalk verification, and duplicate service detection for same-patient, same-date claims. Implement these checks as hard stops in the billing system so that claims cannot be submitted until the issue is resolved.