STATISTICAL INQUIEY 1001 



An accurate collection of facts forms the foundation of 

 statistical inquiry. The importance of a correct diagnosis 

 is here exemplified ; there must be no doubt whatever as 

 to the nature of the cases we are examining ; if there is a 

 doubt they must be rejected from the inquiry. Let us 

 take one or two examples. 



Suppose we wish to ascertain the number of horses 

 which have suffered from sprains of ligaments or tendons 

 during the year ; we must take care that every unit we 

 accept has undoubtedly suffered from sprain, and that the 

 word ' sprain ' has not been used in the record of cases to 

 cover any lameness which could not be diagnosed. In 

 other words, unless we can see or feel a sprain, we cannot 

 be warranted in recording the case as such. If we use the 

 term ' sprain ' to cover the many forms of obscure lame- 

 ness to which the horse is liable, it is evident that the 

 statistical results obtained from such data are worthless. 

 Where it is difficult to make a diagnosis the case must be 

 shown by itself as ' obscure,' and only when the nature of 

 the lameness is beyond all doubt should it receive a name. 



We all know how many cases of lameness there are 

 the nature of which is beyond all doubt,* and it only 

 shows how careful we should be in assigning a cause to 

 lameness, unless, from peculiarity of action, changes in 

 the shape of a part, or history of the case, there can be no 

 reasonable doubt as to the nature of the disease. 



One more example, to show the necessity of accurately 

 collecting facts. We will suppose a horse is seized with 

 colic, and suffers pain for several hours ; this ultimately 

 subsides, is succeeded by obstinate constipation lasting a 

 few days, and ends in death from impaction and enteritis. 

 At the post-mortem examination the cause of the trouble is 

 found to be an intestinal calculus. There can be no doubt 

 in a logical mind in which class such a case should be 

 included; yet, according to a system we have known 



* Our opinion is that 50 per cent, of lame cases are obscure 

 during the earlier stages of lameness, and many remam perman- 

 ently so. 



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