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Medical Coding (ICD-10, CPT, & Modifiers)
Plain-English guides to ICD-10, CPT and HCPCS coding, modifiers, and the payer rules that decide whether a claim pays. Written for practice managers, coders and billers.
102 guides
Down Coding in Medical Billing: Causes, Payer Rules, Appeals
Down coding can mean your own team billed too low or a payer paid a lower E/M level than you billed. Here is how to tell which, confirm it and...
COPD ICD-10 Codes: J44.9, J44.1 and J44.0 Explained
Which COPD ICD-10 code fits the note? A plain map of J44.9, J44.1, J44.0 and J43 for the FY2027 code set, with the documentation each one needs.
ICD-10 Codes for Tick Removal: Billing and Coding Guide
Which diagnosis and procedure codes belong on a tick bite claim, when an E/M is enough, and what the chart must show before 10120 or 10121 is billed.
Onychomycosis ICD-10 Code B35.1: Coding and Billing Guide
B35.1 is the ICD-10-CM code for onychomycosis, but nail fungus claims go wrong around it. Here is when B37.2, L60.3 or L03.03- apply, what the Excludes notes say and what...
Fall ICD-10 Codes: W01, W18 and How to Sequence Them
Which fall ICD-10 codes fit a ground-level fall, how W01 differs from W18.30XA, and why the injury code is always listed first.
Allergic Reaction ICD-10 Codes: T78, T88.6 and Z88 Explained
Which allergic reaction ICD-10 codes fit food, drug, insect and anaphylaxis encounters, and how to tell a reaction code from an allergy status code. Checked against the FY2027 code set.
ICD-10 Codes for Abdominal Surgery: Pre-Op to Aftercare
Which diagnosis codes belong on an abdominal surgery claim: the condition treated, complications such as K91 and T81, and aftercare or status codes, checked against FY2027 files.
Gynecology CPT Codes Guide: Visits, Procedures & Modifiers
A practical map of gynecology CPT codes: how visits, screening, procedures and surgery are grouped, which bundling and global-period rules apply, and how to confirm each code.
CPT Code for RSV Vaccine and Antibodies: 2026-27 Billing Guide
The CPT code for RSV vaccine changes with the product, and infant antibodies are billed differently from vaccines. See the 2026-27 codes and the Medicare Part D rule.
CPT Codes for Laser Therapy: Billing, Coverage and Pitfalls
Which CPT codes apply to therapeutic laser, what 2026 payer policies say about coverage, and how to check before a laser session turns into an unpaid claim.
Cataract Surgery CPT Codes: 66982, 66984 and Billing Rules
A plain-language guide to cataract surgery CPT codes: how to choose between 66984 and 66982, what Medicare expects in the chart, which modifiers apply and how premium lenses are billed.
Mental Health CPT Codes: Evaluation, Therapy and Add-On Guide
A sourced guide to mental health CPT codes: the evaluation, psychotherapy, add-on, crisis, testing and telehealth rules that decide which code a claim needs.
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