Introduction  To find specific pieces of information within documentation, It is necessary to use documentary language. To put it into simple terms, you need a set of keywords ( or authorized terms) and rules for their application. So we call the documentary language a coding system.  In medical field, coding systems are common to document diagnosis and therapies.  Coding means translation or converting the verbal description of disease, injuries, diagnosis, and services into numerical and /or alphanumeric designations for statistical reporting and reimbursement purpose.  The transference of words to numbers

Coding was developed for a number of reasons 1.Tracking disease processes 2. Classification of medical procedures 3. Medical research. 4.Evaluation of hospital utilization. 5.To facilitate the processing of large number of insurance claims. 6.Study hospital cost. 7.Predict health care trends. 8.Plan for future health care needs.

Coding system: Why we need them? Problems: 1-The freedom of expression can cause certain problems Every term may have more than one possible spelling, several synonymous labels may be selected and the whole statement may be structured according to the author's preference Example liver rupture, hepatic laceration, hepatorrhexis 2- The usage of homonymous terms may lead selection of irrelevant data Example in search of MI means myocardial infarction and can produce mesenteries infection.

3- The terms used in documentation do not indicate the degree of similarity. Ex. Two diagnosis as liver cirrhosis and subacute alcoholic hepatic dystrophy similar in administrative analysis but different in epidemiological study Solutions of these problems by coding system Restrict the variability of expression and convert the authorized terms into a short and formal code easier to record. For example: to record the diagnosis of acute appendicitis, you might have to use the code 540

Standards of ethical coding The following standards for ethical coding developed by American Health Information Management Association (AHIMA) on coding and classification are offered to guide the coder in this process 1-Diagnosis that are present on the admission or diagnosis and procedures that occur during the current encounter are to be abstracted after a thorough review of entire medical record. Those diagnoses not applicable to the current encounter should not be abstracted. 2- Selection of the principal Diagnosis and procedures along with other diagnoses and procedures must meet the definition the uniform Hospital discharge Data set (UHDDS)

3-assessment must be made of the documentation in the chart to assure that it is adequate and appropriate to support the diagnosis and procedures selected to be abstracted 4- Medical record coders should use their skills, their knowledge of ICD_9-CM and CP and any other available resource. 5-medical record coders should not change codes so that the meaning of it change represented.Nor should diagnosis or procedure be included or excluded because the payment will be affected,statistical database maintaining a quality database should be a conscientious goal 6- Physicians should be consulted for clarification when they enter conflicting documentation in the chart

7- The Medical record coders is a member of the healthcare team, and as such, should assist physicians who are unfamiliar with ICD_9-CM and CP and DRG methodology 8- The Medical record coder is expected to strive for the optimal payment to which the facility is legally entitled but it is unethical and illegal to maximize payment by means that contradict regulatory guidelines

Classification and nomenclature In planning a data management system, you must decide for every attribute if you should apply a coding system for the objectives of the system, and if it's better to choose a classification or nomenclature Classification (classification system) Are coding systems founded on the \constructing classes? Classes form an aggregation of concepts that match in (at least) one classifying attribute Classification is the categorizing arranging and grouping of diseases, diagnoses, surgical and nonsurgical procedures that have common attributes or characteristics that would signify classifying them in a group such as the body system, communicable diseases,operational procedures of the digestive system and so on.

Example All diseases with classifying attributes of an inflammation of the myocardium as well as of an infectious etiology may be aggregated to the class (infectios myocarditis ).IM You can think of class as a container for objects having this particular attribute. In the example above this could be all discharge diagnoses of the health care institution involving infectious mycarditis. The classes of the classification should cover the relevant domain completely and their contents should not overlap. Each object has to be assigned to exactly one class. When this is done the object is classified. The diagnosis of septic myocarditis, ex might be assigned to the class (infections myocarditis) mentioned above. For the sake of brevity as well as of language independence (if you have edition of the classification in different languages), each class is provided with a code. This could be '357' for infectious myocarditis

'3..' –denoting diseases of cardiovascular system and '35.'- An acute inflammation of heart. The hierarchy expressed in the coding example is typical construction principle of larger classifications. Now, to document a medical fact all you have to do is to find out the appropriate class (put it in the right container) and record the class code. This is what we call coding a medical fact.

Application Classifications are useful in those cases where documentation is used: For patient group analyses (ex. To find out the frequency of cases of infectious myocarditis in the PMC 'Ploetzberg Medical Center' during the last year. To find out all objects that is similar in certain respect (ex. All patient of the PMC having an extended hemicolectomy).

forms The structure of the classification can be 1. hierarchy: The classes of a hierarchical classification are related exclusively either in a generic or in a portative way, ex the subordinate concept, or class, in the hierarchy is either a specialization, or a part of the super ordinate concept. classes Division Subdivision Sections subsection

2.Monohierarchy vs. polyhierarchy In monohierarchy classification there is exactly one superordainate class to every class (expect the topmost or the root of hierarchy). In polyhierarchy classification allow classes to be subordinate to more than one class, which results in several overlying hierarchies.

3. Multiaxial classification (or multidimensional classification) Consist of two or more independent partial classifications. Here, a classifying attribute for each axis is needed, describing an object within different semantic dimension. The object is Typical axes or dimensions you will find in multiaxial disease classification are etiology, topography, and pathology. The partial classifications may themselves be structured hierarchically. In this case you can think of axes as a separate branch or sub- tree of the hierarchy.

Example A simple monoaxial and monohierarchial classification of diagnoses is as follows D1 Disorders of fat metabolisim D11 hyperlipiemia D12lipoproteinemia D121 Tangier Disease D122 A-Beta-Lipoproteinemia D123 other Lipoproteinemia D13 other sidorders of fat metabolism D2 Disorder of carbohydrate metabolism

An additional axis for etiology could contain the classes A1 Nutritional A2 Congenital A3 mixed or other etiology Together with the first axis (what would be its semantic dimension),it forms atow –axial classification (multiaxial classification). hyperlipidemia caused by dietary habits would be code as A1- D11 If you find one class (ex. Viral meningitis) subordinate to two or more different superordinate classes (ex neurological diseases as well as viral diseases)you are dealing with a polyhierarchical classification.

Checklist classification Classification consists of classes that should not overlap and that completely cover the relevant domain completely to achieve completeness, all hierarchical levels should include a class for other however this class will contain little information. Classification of real –life complexity is usually structured hierarchically. You should distinguish between mono-and poly hierarchical classification. A multiaxial classification originates by dividing a classifications concept system into several independent semantic dimensions.

Assigning an object to exactly one class is called classifying, assigning the class code to the object (which includes classifying) and recording it is called coding classification rules can help to find the right class. Classifying always leads to a loss of information (you focus on similarities to other objects in the class and neglect the differences), on the other hand it enables patient –group analyses as well as the complete retrieval of similar objects. To answer the question whether a classification is good or bad, you have to know what kind of analysis you want to do. You need to determine whether it is appropriate or not.1