Temporal precedence
Covariation
Spurious
Single-n designs
Baseline
Stable baseline
A-B design
A-B-A reversal design
Carry-over effects
Multiple baseline design
History
Instrumentation
Maturation
Mortality
Selection
Selection-maturation interaction
Statistical regression
Testing
Pretest-posttest design
Quasi-experiments
Time-series design
Non-equivalent control group design
In this chapter, we address the following questions:
1. How do randomized laboratory experiments establish internal validity?
2. How can single-n studies establish internal validity?
3. What factors may threaten a single-n experiment's internal, external, and construct validity?
4. What are Campbell and Stanley's 8 threats to internal validity?
5. How do quasi-experimental designs deal with the 8 threats to internal validity?