Experimental Designs: Placebo Effect & R.C.T

Question 1

What is Placebo Effect?

Answer 1

An inert treatment with no known effects.

It is known as PLACEBO CONDITION in Repeated Measures
It is known as PLACEBO GROUP in Independant Group design

Question 2

What are ethical issues with using a Placebo?

Answer 2

1. Involves deception (falls outside BPS standards)
2. Possibility of withholding treatment
3. Is there a need to compare new treatments with Placebo’s when effective treatments are available

Question 3

What are Randomised Control Trials? (RCT’s)

Answer 3

Includes both Independent Group and Repeated Measures
(Has an experimental group and a control group being tested on the same Independent variable)

3. Other definitions
   Independent Group Design: Between groups design
   Repeated Measures Design: Within groups (subjects) design
   Randomised Control Trials: MIXED BETWEEN-WITHIN DESIGN

Question 4

How are RCT made up?

Answer 4

They have a control group so the intervention can be compared

Participants are randomly assigned.
This removes experimenter bias, demand characteristics and order effects.

Question 5

How are RCT run?

Answer 5

Randomised groups controlled using counterbalancing (order effects) and blinding (experimenter bias and demand characteristics)

The same variable should be studied in both the experiment group and the control group. No confounding variables will be considered.

Question 6

What are the strengths of RCT?

Answer 6

👍🏼 Only study which can establish causation

👍🏼 Treatments can be administered in a controlled and precise manner

👍🏼 Confounding factors are controlled

👍🏼 No Selection bias due to randomisation

👍🏼 No Interpretation bias because of double blinding

Question 7

What are the weaknesses of RCT

Answer 7

👎🏼 Not suitable for every research question - Doesn’t work for naturally occurring groups

👎🏼 Ethical issues,

(Deception : withholding treatment and why keep using placebos when viable treatments are available)