Homework Assignment 4 example

 

Article:

Vitamin E fails to stop progress of AlzheimerÕs

April 19th, 2005 by Nicolas Bakalar

Source: New York Times

NOTE: you cannot use this article for the homework assignment

 

I.                   Goal: To determine whether taking Vitamin E slows progression of AlzheimerÕs

II.                Model being tested:

Model 1: Vitamin E slows progression of AlzheimerÕs disease

Model 2: Vitamin E does not slow progression of AlzheimerÕs disease

 

III.              Design Features:

1. Experiment:

a) what done: participants were assigned to receive Vitamin E or a placebo

b) for what purpose: to determine the effects of Vitamin E on the rate of pogression of AlzheimerÕs disease

(you can answer this all in 1 simple sentence, just address both parts a and b)

 

                       2. Controls:

a)      was the experiment controlled? Yes

b)      Treatment group = people who took Vitamin E

c)      Control group = people who took a placebo

 

  1. Explicit protocol
    1. relevant: yes
    2. status: present
    3. quotes: Òpatients were randomly assigned to groups receiving a drug Aricept, vitamin E, and placebo versions of those substances.Ó

 

  1. Replication
    1. relevant: yes
    2. status: present
    3. quotes: Òresearchers studied 769 patientsÓ

 

  1. Standards
    1. relevant: yes
    2. status: present

3. quotes: ÒAt the end of one year, significant differences appeared: 38 patients in the placebo group and 33 in the vitamin E group had AlzheimerÕs, compared with only 16 in the Aricept group. But among the 214 patients who progressed to AlzheimerÕs over the entire 3 year course of the study, there was no significant difference among the three test groups.Ó

 

  1. Randomization
    1. relevant: yes
    2. status: present
    3. quotes: Òpatients were randomly assigned to groups receiving..Ó

 

  1. Blind
    1. relevant: yes
    2. status: present
    3. quotes: Òpatients were randomly assigned to groups receiving a drug Aricept, vitamin E, and placebo versions of those substances.Ó

 

NOTE: Placebo will be accepted as evidence that study was done blindly.