FIELD E ; Pathology Code 



Columns 18, 19, 20, 21, 



22, 23, 24, and 25 



anatomically only and which omits any etiological association; this is usually accompanied in the list 

 by one or more items, each defining that state in which one of the possible known etiologies is 

 specified and that specification is made in the symbol . Cirrhosis, for example, may have any of 

 several recognized causes and cirrhosis is given a coding identity (by Parts II and IV of the symbol, 

 Columns 19, 20, and 21 and 24 and 25) independent of the etiology (Part III, Columns 22 and 23). 

 Cirrhosis is recognizable, therefore, even when no etiology is expressed (TE1 00002), as well as when 

 it is due to a known cause (TE1 04202). 



On the other hand, when an item is included in the list defining a non-infectious state of 

 whose origins medical science has no certain knowledge, it is assigned a definite etiological symbol 

 specifying that (Symbol 7, G, P, or X, or 8, H, Q, or Y, in Column 22). All such diseases are given 

 secondary classifications based on the anatomical effect of the disease or on the physiological action 

 disrupted by the disease, whichever is the more characteristic manifestation of the pathology. Osteo- 

 arthritis and rheumatic fever are examples of specific recognized diseases whose etiologies are still 

 conjectural; the etiological symbols for those diseases specify this (T9307J0A and TB00G102, 

 respectively). 



Coding etiological factors has necessitated constructing a special list of etiologies to which 

 diseases can be referred and from which symbols can be taken to construct unique Field E symbols for 

 the Pathology Code. For this, the etiology organization of the American Medical Association "Standard 

 Nomenclature of Diseases and Operations" has been used as a guide. 



Columns 22 and 23 of Field E are designated for coding the etiology of a non-infectious pathology 

 and these 4th and 5th units of the total Field E pathology symbol represent the third part of the symbol 

 (i. e. , the third category of information identifying and indexing diseases). The special list of etiologies 

 and their symbols is included in the Code following the list of pathologies for which symbols have been 

 constructed. While the classification itself can scarcely be described as provisional or unproved, 

 since it is basically that of the AMA scheme, the proposed rather rudimentary adaptation should be 

 regarded as candidate for further study and development. 



By reference to the etiological classification in the Code, it will be seen that, in each of the 

 eight major etiological categories, 140 symbols are available for specific etiologies. The basic symbol 

 for each of the eight major categories is a numerical symbol in Column 22, Symbol 2, 3, 4, 5, 6, 7, 8, 

 or 9. Each of the eight symbols can be combined with each of the three IBM zone punches to represent 

 letter symbols. Thus, the first etiological category is represented in Column 22 by Symbol 2, Symbol B 

 (the IBM punch in the "2" position plus the 12 zone punch), Symbol K (the 2 punch plus the 11 zone 

 punch), and Symbol S (the 2 punch plus the zone punch). The second category is represented by 

 by Symbols 3, C, L, and T; the third category by Symbols 4, D, M, and U; and so on. 



Symbol 1 has not been used in Column 22 for an etiological designation, because it can not be 

 combined with the IBM zone punch and given meaningful interpretation on the IBM equipment used 

 by the CBCC and because the remaining symbols (2 through 9) have seemed adequate for all the 

 etiological categories needed. The two etiological categories, infectious organisms and tumors, are 

 omitted, because they are given special coding treatment, although the eighth category (Symbol 9 in 

 Column 22) refers to an infectious agent in the history of a disease as being the typical initial pre- 

 disposing factor to the disease by definition. In the latter case, since the organism is no longer 

 present, the chemical treatment of such a disease is incapable of affecting the infectious organism as 

 a living system, and the basic reason for identifying the disease by a Taxonomy Code symbol there- 

 fore does not exist. 



Within a major category, the available symbols have in most cases been distributed to provide 

 a reasonable secondary classification of etiologies. For example, within the fifth category, the symbols 

 are divided among specific subcategories so that Symbol 6 in Column 22 is designated to specify 

 metabolic disorders and toxins of metabolic origin as causes of pathology, Symbols F and in Column 

 22 are assigned to specific deficiencies as causes of pathology, Symbols Wl through WR indicate 

 endocrine functional abnormalities as causes of pathology, and Symbols WS through WZ indicate 

 specific disorders in growth and development as causes of pathology. 



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