The medical notes may also be divided into specialities, for example cardiology, gastroenterology, nephrology, neurology, pulmonology or orthopedic care.
A clinical coder therefore requires a good knowledge of medical terminology, anatomy and physiology, a basic knowledge of clinical procedures and diseases and injuries and other conditions, medical illustrations, clinical documentation (such as medical or surgical reports and patient charts), legal and ethical aspects of health information, health data standards, classification conventions, and computer- or paper-based data management, usually as obtained through formal education and/or on-the-job training.
[3][4] The basic task of a clinical coder is to classify medical and health care concepts using a standardised classification.
Inpatient, mortality events, outpatient episodes, general practitioner visits and population health studies can all be coded.
[5] The abstraction phase involves reading the entire record of the health encounter and analysing the information to determine what condition(s) the patient had, what caused it and how it was treated.
Clinical coder must ask themselves, "does this code set fairly represent what happened to this patient in this health encounter at this facility?"
Depending on the country, this program may be in the form of a certificate, or even a degree, which has to be earned before the trainee is allowed to start coding.
In some countries, clinical coders may seek voluntary certification or accreditation through assessments conducted by professional associations, health authorities or, in some instances, universities.
The National Clinical Coding Qualification (NCCQ) is an exam for experienced coders, and is recognised by the four health agencies of the UK.
In England, a novice coder will complete the national standards course written by NHS Digital within six months of being in post.
Three years after passing the NCCQ, two further professional qualifications are made available to the coder in the form of NHS Digital's clinical coding auditor and trainer programmes.
As of 2016[update], the typical qualification for an entry-level medical coder in the United States is completion of a diploma or certificate, or, where they are offered, an associate degree.
The diploma, certificate, or degree will usually always include an Internet-based and/or in-person internship at some form of a medical office or facility.
Both the CPC and COC have apprentice designations (CPC-A and COC-A, respectively) for those who pass the certification exams but do not have two years of on the job experience.
This trend was accelerated in part by the passage of HIPAA and the Affordable Care Act and similar changes in other Western countries, many of which use the ICD-10 for diagnostic medical coding.