FIELDS W, X, and Y 



Columns 68; 69 and 



70; and 71 



Criterion 57: 20% of the individuals to which the test compound had been administered at the coded 

 dose survived 2-3 hours longer than controls, 60% survived 3-4 hours longer than 

 controls, 15% survived 4-8 hours longer than controls, and 5% survived 8-10 hours 

 longer than controls. Interpretation of these data for plotting on the Grid (the following 

 percentage figures represent the points to be plotted on the ordinate of the Grid): 5% of 

 the individuals survived 8-10 hours longer than controls, 20% of the individuals survived 

 4-8 hours (or more) longer than controls, 80% survived 3-4 hours (or more) longer than 

 controls, and 100% survived 2-3 hours (or more) longer than controls. The reciprocal 

 of the value coded in Column 66 of Field U is to be plotted on the abscissa. 



Criterion 58: 20% of the individuals to which the test compound had been administered at the coded 

 dose responded in 5-6 minutes, 40% responded in 7-8 minutes, 30% responded in 9-10 

 minutes, and 10% responded only after 15 minutes. Interpretation of these data for 

 plotting on the Grid (the following percentage figures represent the points to be plotted 

 on the ordinate of the Grid): 20% of the individuals responded in 5-6 minutes, 60% had 

 responded after 7-8 minutes, 90% had responded after 9-10 minutes, and 100% had 

 responded only after 15 minutes. The value coded in Column 66 of Field U is to be 

 plotted on the abscissa. 



Criterion 59: 10% of the individuals to which the test compound had been administered at the coded 

 dose were dead after 1 hour, 40% were dead after 90 minutes, 80% were dead after 2 

 hours, 90% were dead after 3 hours, and 100% were dead after 8 hours. Here, 10%, 

 40%, 80%, 90%, and 100% represent the points to be plotted on the ordinate of the 

 Grid. The value coded in Column 66 of Field U is to be plotted on the abscissa. 



Criterion 54, 57, 58, or 59 can only be used if the test compound actually produces the 

 response coded in Field T. (If the response were not produced, only Criterion 01, 02, or 62 would be 

 used with Symbol 1 in Field Y. ) Therefore, Symbol J or K would never be used in Field W when 

 Symbol 54, 57, 58, or 59 is coded in Field X. If the test compound has been administered only at the 

 maximum tolerated dose, Field W is coded with Symbol M. If the dose administered in the test being 

 coded is known to cause the greatest duration of response (or the greatest increase in survival time, 

 the shortest time to specific action other than death, or the shortest killing time) of which the test 

 compound is capable, Field W is coded with Symbol or N, according to whether the dose was known 

 to be the minimum necessary to cause that maximum intensity of response. If the dose administered 

 In the test being coded is not demonstrated to cause the maximum intensity of which the compound is 

 capable (i. e. , the greatest duration of response, shortest killing time, etc. ), but is known not to be 

 in excess of the amount needed to cause the maximum intensity of response, code Field W with 

 Symbol P. 



21. Criterion 55; evaluation of potency of the test compound in terms of the antagonism ratio 

 (relative quantities of antagonized compound and antagonist) correlated with the percentage 

 of organisms responding 



Reference should be made to Division 16 which describes Criterion 22 and explains that that 

 criterion as well as Criterion 55 can be used only when the response produced by the secondary 

 compound administered alone is antagonized 100% by the test compound. In the case of Criterion 22, 

 a code rating is derived by simply relating dosage sizes of the secondary compound and the test 

 compound (deriving an antagonism ratio). In the same way, a dosage ratio is calculated for Criterion 

 55; the quantity of test compound needed to antagonize completely the action of the secondary compound 

 is related to the quantity of secondary compound antagonized. The ratio, as established for Criterion 

 22, is reversed in Criterion 55. As in the case of Criterion 22, the ratio can be placed on a special 

 scale accompanying Criterion 55 in the Code. By this scale, dose values are derived (1-9) which, 

 unlike Criterion 22, are not used directly as code symbols but are correlated with the percentage of 

 Individuals in which antagonism was accomplished by the dosage Indicated by the antagonism ratio. 

 The correlation is made by the Log-Probit Grid. The dosage ratio is reversed from that used for Criterion 

 22 because of the use to be made of the ratio on the Grid. The ratio of Criterion 2_2 will be seen to ex- 

 press the amount of secondary compound antagonized by each unit of test compound . Criterion 55^, how- 

 ever, is concerned with comparing all test compounds on the basis of the amount of each test compound 

 capable of antagonizing a unit of the secondary compound , this amount of test compound being related 

 to the percentage incidence by the Grid. 



202 



