FIELDS H-l and H-2 

 Columns 29, 30, 31, 

 32, 33, and 34 



General Use 



In the case of many tests for biological responses to chemicals, specific anatomical parts of 

 the organisms involved represent significant aspects of the test method or response. The area of the 

 Code that is devoted to expressing these specific structures comprises Field H-l and Field H-2, for 

 gross anatomical parts, and Field I, for tissue and cellular parts. Although this section, as well as 

 the following section on Specific Directions and Explanations, concerns principally Fields H-l and 

 H-2 (gross anatomy). Field I (microanatomy) will frequently be mentioned with them; the three fields 

 together make a unit for coding of structural parts, since the relationships of each of the three fields 

 to other fields of the Code are essentially identical. 



There are two fields in which an organism may be coded: Field E, for the test organism, and 

 Field J for the host organism. Since the CBCC Code has only one area for coding anatomical structures, 

 as indicated in the preceding paragraph, the anatomy fields (H-l, H-2, and I) must serve both Fields 

 E and J. The relationships, however, are not difficult to understand: Whenever an organism is coded 

 in Field J (indicated by any Field J symbol other than those beginning with letters S through Z), the 

 entry in Field H must be a structure of the host coded in Field J. When Field J is not coded, or is 

 coded with only a culture medium or environment (indicated by any Field J symbol beginning with letters 

 S through Z), the entry in Field H must be a structure of the test organism coded in Field E. 



Frequently, a test involves two types of information (and occasionally more than two) which 

 concern anatomical structures, both of which are significant. It is for this reason that two fields have 

 been provided instead of a single one. The types of information coded in Fields H-l and H-2, the 

 distinction between the use of Fields H-l and H-2, and the relationship between these two fields 

 (H-l and H-2) and other fields (E, G, J, L, S, and T) are indicated briefly in the following paragraphs. 



There are four general uses for Fields H-l and H-2: 



1 . To record the gross anatomical structure or system responding to the compound or the structure 

 or system in which the response is measured, this structure or system being of the test organism or of 

 the host, as explained above in the second paragraph of this section . This first use represents the 

 primary purpose for a coding provision for anatomy. FOR THIS PURPOSE, ONLY FIELD H-l IS USED. 



The remaining three uses of Fields H-l and H-2 are for aspects other than specific responses 

 of organs or systems to the test compound. 



2. To record a gross anatomical structure or system which has been experimentally modified 

 (chemically, surgically, etc. ) prior to treatment with the test compound . Such modification may be 

 made on either the test organism (coded in Field E) or on the host organism (coded in Field J) and the 

 specific modification is indicated in Field G (for a test organism) or L (for a host organism). 



When the experimental state coded in Field G or L refers to an anatomical structure that has 

 been modified, the definition of the Field G symbol or Field L symbol in the Code includes the reference 

 to Field H-l, H-2, or I. Therefore, if the experimental modification was to the organ specifically 

 responding to the test compound or the organ in which the test response is measured (see Use Number 1 

 above), only a Field G or Field L entry can be used which refers to Field H-l. This is always indicated 

 in the Field G or Field L definition (e. g. , Symbol N of Field G: organ studied [specified in Field H- 1] 

 in a pathological state. . . ). Similarly, if the modification is made to an organ other than the organ 

 specifically responding, the Field G or Field L entry refers to Field H-2 and the Field G or Field L 

 definition always directs the coder to make the entry in Field H-2 (e. g. , Symbol of Field G: organ 

 [specified in Field H-2] in a pathological state). 



3. To record the gross anatomical structure or system to which the test compound was applied . 

 Field H-2 is used to supplement the description of the route of administration (coded in Field S-3), 

 when the route of administration is not to the organ specifically responding (in Field H-l) and when the 

 symbol used in Field S-3 can not adequately specify the organ or body area to which application was 

 made. See Division 2 of Specific Directions and Explanations. 



4. To record the gross anatomical structure or system which is the site of the tumor or patholog- 

 ical condition coded in Field E (Field H-l, rarely Field H-2). When Field J is coded with an organism 



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