PRE-EXPERIMENTAL DESIGN

Pre-Experimental Research Designs

Learning Outcomes

Understand and describe about Pre-Experimental Research designs
Identify and describe the various types of Pre-Experimental research designs
Distinguish between Pre-Experimental designs from other experimental designs

Pre-Experimental Research Designs

Pre experimental research designs are research schemes in which a subject or a group is observed after a treatment has been applied, in order to test whether the treatment has the potential to cause change. Campbell and Stanley described 3 general types of experimental research designs – Pre-Experimental, Quasi-Experimental and Full or True Experimental design.

Figure.1

The Proponents of different Experimental designs are given in the Figure.1

Types of Pre-Experimental Design

Ø One-shot case study design

Ø One-group pre-test-post-test design

Ø Static-group comparison

One-shot case study design

A single group is studied at a single point in time after some treatment that is presumed to have caused change. The carefully studied single instance is compared to general expectations of what the case would have looked like had the treatment not occurred and to other events casually observed. No control or comparison group is employed.

One-group pre-test-post-test design

A single case is observed at two time points, one before the treatment and one after the treatment. Changes in the outcome of interest are presumed to be the result of the intervention or treatment. No control or comparison group is employed.

Static-group comparison

A group that has experienced some treatment is compared with one that has not. Observed differences

between the two groups are assumed to be a result of the treatment

Characteristics

v It happened before a true experiment is conducted.

v Researcher has very little control over the experiment and variables.

v Only the effect of independent variable on dependent variable is measured

v Validates the experiment in the preliminary phase itself.

v It tells researchers how their intervention will affect the whole study.

Advantages

Ø Cost effective due to its easy process

Ø Very simple to conduct

Ø Efficient to conduct in the natural environment

Ø It is also suitable for beginners

Ø Involves less human intervention

Ø Determines how your treatment is going to affect the true experiment

Disadvantages

Ø It is a weak design to determine casual relationships between variables

Ø Does not have any control over the research

Ø Possess a high threat to internal validity

Ø Researchers find it’s tough to examine the result’s integrity

Ø The absence of a control group makes the results less reliable

Table.1

The differences across Experimental designs which is given in the Table.1

	Pre-Experiment	Quasi-Experiment	Full Experiment
No: of Conditions	One or more	One or more	Two or more
Random assignment	No	No	Yes
Use of Pre-tests	No	Yes	Sometimes
Level of Control	Low	Moderate	High