Module 3 – Choosing your research strategy

Fixed Designs

Experimental Fixed Designs

Non Experimental Fixed Designs

True Experimental Designs (p124 Box 5.5)

The defining characteristic of a true experimental design is the random allocation of participants to the two (or more) groups of the design

• Two Group Designs

1. Post-test-only randomised controlled trial (RCT)
2. Post-test-only treatment comparison
3. Pre-test post-test RCT
4. Pre-test post-test two treatment comparison

• Three- (or more) group simple designs
• Factorial Designs
• Parametric Designs
• Matched Pair Designs
• Repeat Measures Designs

(P156 Box5.21) Non experimental fixed designs follow the same general approach as that used in experimental designs but without the active manipulation of variables by the researcher characteristic of experimentation

• Relational Designs

1. Cross-sectional; designs
2. Prediction Studies

• Comparative Designs
• Longitudinal Designs

Quasi- Experimental Designs (p136 Box5.14)

A quasi-experimental design follows the experimental approach to design but does not involve random allocation of participants to different groups. Some commonly used designs:

• Pre-experimental designs

1. Single-group post-test only
2. Post-test only non-equivalent groups
3. Pre-test post-test single group design

• Pre-test post-test non-equivalent group designs
• Interrupted time series designs
• Regression-discontinuity designs

Single Case Experiments (p148 Box 5.20)

These designs call for a series of measures on a dependent variable (DV) (or, more rarely, on two or more such variables). Typically the study is repeated with a small number of participants to establish the replicability of findings.

• A-B Designs
• A-B-A Designs
• A-B-A-B designs
• Multiple base-line designs

1. Across settings
2. Across behaviours
3. Across participants