ICD-10 Medical Coding (30+ Q&A) – Diagnosis Coding, Z Codes, Tabular Rules, 7th Characters | 2025/2026

This essential guide contains 30+ correctly answered ICD-10-CM exam questions, updated for the 2025/2026 coding cycle, and is tailored to support students, coders, and health information professionals learning the foundations of diagnostic medical coding. It reviews the core principles of navigating the ICD-10-CM system, selecting the most specific diagnosis codes, and understanding formatting rules and conventions. Topics covered include: Coding structure & syntax: Character positions (3–7), use of X as a placeholder, when to use the 7th character extension Tabular List & Alphabetic Index rules: Brackets, hyphens, cross-references (e.g., “see also”), and the use of subterms Code categories and examples: Respiratory system (J00–J99), malignancies (C codes), and S82 as a category code Special terms: Definitions and usage for NOS (unspecified), sequelae, and “other” coding rules Z codes: Application for encounters unrelated to disease or injury (e.g., follow-ups, screenings, vaccinations) Outpatient coding guidance: How to code reasons for surgery and selecting the first-listed diagnosis Updates to ICD-10-CM: Understanding what addenda are and how annual updates affect practice This resource is especially helpful for: Medical coding students (ICD-10-CM focused) HIM and HIT learners preparing for exams (e.g., CCS, CCA, CPC) Nursing or healthcare admin students needing coding literacy Clinical professionals reviewing ICD-10-CM logic and structure Presented in a straightforward Q&A format, this guide supports quick study, code interpretation, and exam prep. Keywords: ICD-10-CM, diagnosis coding, z codes, sequelae, NOS, code structure, seventh character, placeholder X, Tabular List, Alphabetic Index, outpatient coding, coding addenda, code categories, S82, J00-J99, malignancy codes, subterm, unspecified codes