Why would a study involving continuous handrail support, oxygen ...

[Pineappleeh]

Why would a study involving continuous handrail support, oxygen uptake, and heart rate in women during submaximal step treadmill exercise be quasi-experimental in design versus experimental?
 
  a. The sample size was small.
  b. Randomization was not used in sample selection.
  c. The dependent variables were not manipulated.
  d. The independent variables were not manipulated.

Question 2

How could the sample selection procedures used in a research study investigating the levels of depression occurring in blind and sighted adolescents make the sample of blind adolescents more homogeneous?
 
  a. Eliminate subjects taking prescription medications
  b. Narrow the age range of subjects to those between 13 and 18 years
  c. Have the same person administer the questionnaire to all subjects
  d. Avoid telling the subjects the nature of the study

[at]

Answer to Question 1

ANS: B

Feedback
A The size of the sample does not primarily affect the nature of the study design.
B The major difference between experimental and quasi-experimental designs is lack of randomization in sampling selection.
C Dependent variables or outcome variables are not manipulated.
D Independent variables (or the treatment) must be manipulated to conduct an experiment or quasi-experiment.

Answer to Question 2

ANS: A

Feedback
A Because many potential subjects take prescription medications, elimination of subjects taking prescription medications would make the sample homogeneous.
B Narrowing the age range of subjects in an adolescent study would not necessarily increase homogeneity.
C Having the same data collector would not alter the nature of the sample.
D Not sharing the nature of the study with subjects would not alter sample characteristics.

[Pineappleeh]

Thanks for the timely response, appreciate it

[bulacsom]

Excellent