DrAnderson Is a Nutritionist Who Helps Clients Lose Weight Prior

Dr.Anderson is a nutritionist who helps clients lose weight prior to surgery.She is working with W.J. ,a male client who is planning on undergoing a heart transplant.He currently eats more than 3,500 calories a day and has been asked by his doctor to cut the number of calories to about 1,800 (400 for breakfast,600 for lunch,and 800 for dinner) .She is curious as to whether a food journal will help W.J.reduce the number of calories he eats.A food journal is used to record everything a person eats.Dr.Anderson decides to phase in the food journal gradually,initially only recording what is eaten at breakfast during the first three days after baseline (days 4-6) .During days 7-9,the journal is used at lunch,too,and during days 10-12,it also is used during dinner.Each day,Dr.Anderson's client sends her entries from the food journal and the number of calories he ate at each meal (as calculated by his wife,whose help she enlisted) .The data for Dr.Anderson's study are below.


-In interrogating the statistical validity of Dr.Anderson's study,which of the following might be asked?

A) By what margin did W.J.'s calorie intake improve?
B) How accurate was W.J.'s wife in her calculation of the calories consumed at each meal?
C) Was the number of calories consumed by W.J.going to decrease before surgery anyway?
D) Was Dr.Anderson qualified to analyze the data?