A veterinarian wishes to compare the number of times race horses are reported to be lame during a 12‑month period, as compared w
ith similar horses that are not raced. The veterinarian is particularly interested in whether the exercise schedule used in racing contributes to lameness, rather than the total amount of exercise. The veterinarian feels horses to be compared should be similar with regard to age, breed, and the number of weekly hours spent exercising. Which of the given study types should be used?
The objective of the veterinarian is to check if racing contributes to lameness in racing horses. To conduct a test the veterinarian should select at random two groups of horses, group one will be of racing horses and group two should be of not racing horses. Other than racing, all the other differences between the horses that may cause lame or resistance to lame should be controlled( confounding variables) such as age, breed, the number of weakly hours spent exercising, diet, obstacle-free environment, etc...
This type of study is an experimental design.
The experimental design is an analytic essay characterized by the fact that the investigator controls the study variable and the randomization of the samples. In which all the variables are controlled except the ones that you wish to study.