FIELD W 

 Column 68 



A. QUAUFICATION OF THE NEGATIVE AND 

 POSITIVE CHARACTER OF TEST RESULTS 

 AND QUAUFICATION OF THE CODED DOSE 



B. INFORMATION ABOUT SLOPE OF THE 

 DOSAGE-RESPONSE CURVE 



Introduction to Field W 

 Symbols J through Q and * 



A. The basic objective of the symbols of Field W, with the exception of Symbol *, is to classify 

 the character of the negative or positive biological response (whose quantitative measure or evaluation 

 is coded in Field Y according to a criterion coded in Field X) and of the dose (coded in Fields M, N, O, 

 and P) according to whether the test coded demonstrated: 



(1) Inability of the test compound to produce the response when administered to the test 



'-' organism at any level below a toxic level or below any level impractical to administer: 



!^ o Symbol K (Symbol J indicates that the test did not prove the test compound was unable 



^"^ to produce the response even though the response did not occur at the dose administered); 



CM 



"? ^ ra (2) The maximum intensity of test organism response which the test compound is capable of 



O T) 



a 



inducing; Symbol M, N, or (Symbols L and P indicate that the test did not prove that 



(3 * c the intensity of response was maximal, since a dose larger than the largest tested might 



J2 c 5 cause a higher response intensity); 



o (0 o 



•o . ^ 



!_ '^ ° (3) The minimum dose of test compound needed for the intensity of response produced in the 



" ^^ test organism, whether or not it is the maximum intensity of which the compound is cap- 



^ . ■" able: Symbol P (if the intensity of response is threshold intensity or any intensity below 



2 ^ maximum intensity or if the intensity is not known to be maximum intensity) or Symbol 



•2 ■£ (if the intensity of response is known to be maximal). (Symbols L, M, and N indicate 



that the test did not prove that the coded dose was the minimal needed. ) 



The classification will be seen to be dependent at certain points (Symbols J, K, L, and M) on whether 

 information is known about the toxic character of the chemical tested and the limitations placed on the 

 chemical's application by that character. Whether the test compound has such limitations can ordinarily 

 be determined only by having performed, prior to or contemporary with the test being coded, one or more 

 other tests at different dose levels, the limiting toxic effect being revealed by one of the higher dose 

 levels in one of the tests. Thus, incidentally. Field W conveys further information about the character 

 of the dose coded in Fields M, N, O, and P as follows: 



(4) The dose coded in Fields M, N, O, and P is known to be the maximum tolerated or (if 

 the test compound causes no toxic effect at any dose) the largest dose that can be 

 administered, for any reason other than toxicity and limitation of availability: Symbol K 

 or M and (only if Symbol 21 is in Field X) Symbol or P; the use of Symbol N or 

 implies that the coded dose is known not to be the MTD, except when Symbol 21 is in 

 Field X with Symbol in Field W; (Symbol J, L, or P: the coded dose is not known 

 either to be or not to be the MTD, unless Symbol 21 is in Field X with Symbol P in 

 Field W). 



For sake of clarity, the definition for each of Symbols J through Q is presented as a set of brief state- 

 ments, the statements collectively setting forth the conditions under which the symbol is used and the 

 implications made by it. The definition and use of each of the symbols are discussed in more detail in 

 the Key section on General Use of Fields W, X, and Y. 



B. One Field W symbol is also provided to be used when the data (of a journal article, laboratory 

 report, etc. ) include Information on the slope of the dosage-response curve. This symbol (Symbol *) 

 does not itself code information about the curve, but is only a key to the fact that the information exists 

 with the data. The written abstract on the Code Sheet must be consulted to find the information or 

 reference must be made to the original data. 



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