Case Studies, Small N Designs, and developmental designs

Question 1

Case Study

Answer 1

-Provides a detailed description of an individual
-Observational
-Includes:
-Interview
-Physiological Recording
-Behavioral Tasks
-Psychological Tests

Advantages:
-Detailed Info
-Permits investigation of otherwise impractical or unethical situations

Disadvantages:
-Internal and external validity

Question 2

Small N Designs

Answer 2

Advantages:
-Able to study rare issues
-Higher internal validity than some (e.g, case study)
-Practical
-Led to cool discoveries

Disadvantages:
-Not as high internal validity as a randomized experimental design
-Can lack external validity for generalizing to population

Question 3

Small N Design: Single case baseline

Answer 3

-Outcome (usually a behavior) is assessed during a baseline period, then manipulation is added, and outcome is assessed

-Higher Validity than case study but still many confounds
-History and maturation

Question 4

Small N Design: Multiple Baseline

Answer 4

-Across subjects:
-Observe change with multiple people where the treatment has been given at different times

-Across Behaviors
-Across situations
-Home v. Work

Question 5

Small N Design: Reversal

Answer 5

-Giving and then removing the treatment
-ABA
-ABAB

-Higher internal validity

Question 6

Small N Design: Multiple-Component Designs

Answer 6

-ABC, ABCD
-Add more treatment types/comparison conditions
(Placebo)

-Issues
-Order effects but can be addressed with reversal

Question 7

Developmental Research Design: Cross-Sectional

Answer 7

-Separate groups into cohorts and test something at one point in time

Question 8

Developmental Research Design: Longitudinal

Answer 8

-A sample is observed at different times as they age

Question 9

Sequential/Cohort-Sequential

Answer 9

-Part longitudinal and part cross-sectional
-Cohorts but over time

Question 10

Attrition

Answer 10

-People leaving the study

Random v. Non-Random
-If attrition is random, you only have to worry about reducing sample size
-If attrition is not random it might affect results and conclusions might not be valid

Question 11

Developmental Research Design: Trend Design

Answer 11

-Data are collected at two or more points in time from different samples of same population

Steps:
1. Collect data from a sample from population at T1
2. Time passes, some people leave population and others enter it (e.g, college students graduating and new students starting)
3. At T2, a different sample is drawn from population