A team of biomedical engineers designed a prototype device for assisting in obstetric delivery (International Journal for Service Learning in Engineering, Fall 2012). To determine the effectiveness of the device, five medical students were recruited to participate in the study. Initially, each student was asked to deliver a model “baby” from a birthing simulator using the prototype device without any training on its use. A pretraining score was assigned based on the time taken to deliver the model, with penalties incurred for errors during the procedure. A higher score (the maximum score was 900 points) indicated a more proficient use of the prototype. Next, each student participated in a 30-minute training workshop on the use of the prototype device. Following the workshop, the students repeated the birthing test and a post-training delivery score was assigned to each. The team of biomedical engineers want to estimate the average increase in delivery score following training.

a. What is the parameter of interest to the engineers?

b. Give details on the design used to collect the data.

c. The following information was provided in the article: y̅_Pre = 481.8, y̅_Post = 712.4 . Is this sufficient information to find the estimate of the parameter of interest? If so, give the estimate?

d. The following additional information was provided in the article: S_Pre = 99.1, S_Post = 31.0. Is this sufficient information (along with the information in part c) to find a 95% confidence interval for the parameter of interest? If so, give the interval estimate? If not, what further information do you need?