FIELDS W, X, and Y 



Columns 68; 69 and 



70; and 71 



eventuality, Criteria 14, 15, and 16 are provided. Since these criteria measure the compound's value 

 in curing or producing relief from a disease and can be used only when such action has been demonstrated, 

 it follows that when those criteria are used, the action coded in Field T is necessarily that of curing 

 the organism of, or producing some degree of relief from, the disease; thus, when Criterion 14, 15, or 

 16 is used, the biology code line records the details of the therapeutic test; Criteria 14, 15, and 16 

 are never used to evaluate the compound's ability to kill the diseased host. 



Ordinarily, when the author gives the minimum lethal dose as well as the index, the therapeutic 

 dose level can be calculated for Fields M and/or N and the use of Criterion 14, 15, and 16 can be 

 avoided. When the coder must use Criterion 14, 15, or 16, it is because he has only the calculated 

 index and can not determine the therapeutic dose; therefore, when Criterion 14, 15, or 16 is used, 

 Fields M and N can not be coded. 



Because of the usefulness of the index values in comparing chemicals on their therapeutic 

 merits, it is conceivable that under certain circumstances, it would be worth the time and expense to 

 construct biology code lines with the therapeutic index or the chemotherapeutic index coded in Fields 

 X and Y, in addition to constructing the two code lines evaluated by the therapeutic dose level and by 

 the lethal level, when the latter two values are known. The CBCC has actually constructed such code 

 lines, using Criteria 14, 15, or 16, in addition to constructing lines evaluated by the therapeutic dose 

 level and by the lethal level, in coding data from certain large screening projects, when many chemicals 

 have been tested identically, resulting in many chemotherapeutic indexes of considerable value because 

 they referred to the same treated condition. 



Ordinarily, data which evaluate a test compound by therapeutic or chemotherapeutic indexes 

 are known to be positive data and if Criterion 14, 15, or 16 is used, Field W should be coded with 

 Symbol 0, since the therapeutic dose is claimed by definition to have been determined to be the 

 minimum needed to cause the desired (maximum) therapeutic response. 



12. Criterion 17; rodent repellency index 



The quality of a compound which enables an organism to sense the compound and be repelled 

 by it or be attracted to it can be measured by the percentage of a group of organisms repelled or 

 attracted or by the quantity of the compound needed to repel or attract. 



In testing chemicals for their repellent/attractant quality for rats, a special method has been 

 devised which consists basically of applying the test compound to the food of laboratory rats at a 

 fixed dose level and subsequently comparing the consumption of that treated food to the consumption 

 of untreated food offered concurrently to the rats, any marked preference on the part of the rats being 

 taken as a measure of the repellent/attractant quality of the compound. 



Results from this test procedure are expressed by a "repellency index" which is the result of 

 a standard calculation, the formula for which is as follows: 



K = 100 - 1/100 W (8Tj + 4T 2 +2T 3 + T 4 ) (U t +U 2 + 2U 3 +4U 4 +8X) 



In this formula, W represents the body weight of the animal in kilograms, Tj, T^, T3, and T 4 

 represent the daily consumption of the treated food (the standard duration of the experiment is 4 days), 

 Uj, U^. U3, and U4 represent the daily consumption of the untreated food, and X represents any 

 untreated food remaining at the end of the experimental period. 



Inasmuch as hundreds of compounds have been given this particular test and rated according to 

 the calculation above (using the fixed dose of 2% in the food), the CBCC has assigned a unique Field X 

 symbol to the repellency index, Symbol 17. On advice from investigators using the test, relative to 

 the significance of the repellency index, a Field Y rating scale has been established using Symbols 1, 

 3, 5, 7, and 9. An index value less than 80 is regarded as being indicative of a repellency too low to 

 be given practical consideration in the investigator's opinion and subsequently it is coded in Field Y 

 with Symbol 1; this does not always mean that the test compound proved totally nonrepellent. Actually, 

 evaluation by Criterion 17 represents a special "Author's Evaluation" (Criterion 01) and the criticisms 

 made of Criterion 01 (see Divisions 4, 6, 7, and 8) would apply equally to Criterion 17, except that, 

 by Criterion 17, the basis for the author's statement (i. e. , the author's criterion) is specified by 



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