Research Methods

• Reminder: exam #1 a week from today
• Need to check with me regarding clinical
paper topic. Deadline Oct. 3rd
• Upcoming assignment: parent interview.
See handout.
Research Methods
Types of Investigations
1. Naturalistic or Observational Studies
(correlational studies; studies with quasiexperimental designs)
A. Characteristics of correlational studies
B. Relationships/Causality
e.g. Harvard students/SAT
e.g. TV watching and aggression in children (see
next slide)
TV and aggression
• Headlines:
“TV Time Yields Violence” (The Boston Globe)
“Just an hour of TV time a day leads to
violence” (Reuters)
Three ways that relationships can work:
1. TV causes aggression
2. Aggression causes TV watching
(e.g. no friends, time to kill)
3. Third variable causes them both
Example: health of babies born to smoking and
nonsmoking parents
Classic Experimental Studies
Need to meet two conditions:
1. Random assignment to groups
2. Experimental control
Steps to design an experimental study
1. Operationalize independent and dependent
2. Randomly assign participants to groups
Classic Experimental Studies
1. Greatest strength is causality
2. Main problem is inability to use random
3. generalizability
Single Subject Design
(Case studies and within subject designs)
1. Case studies
Used to figure out what might be important
Used when situation or disorder is very rare
2. Single subject designs
Used to assess change in behavior related
to an intervention
A – B – A –B design
Time Frame of Studies
1. Cross sectional research
Cheaper, easier but can’t look at change over
2. Prospective longitudinal design
Capture developmental processes but timeconsuming
3. Accelerated longitudinal design
Cohort sequential design
Pedro-Carroll & Cowan divorce
intervention study
• Establishes importance of research
• Reviews prior research
• Highlights gaps, builds
Didn’t address developmental impact of divorce
Doesn’t address divorce vs. prior conditions
Why chose particular areas??
Divorce intervention study cont’
1. Low dropout rate
2. Control group and random assignment
3. Range of sources of info./measurements
Expectancy effects
Variability in post divorce time
No attention control group – reactivity?
No info. on measures used
Review for exam
Know everything
• Developmental psychopathology model
• Risk/resilience/protective factors
• Several questions on research methods and
interpretation of findings
– Be able to design a study
– Be able to interpret results from each method (what
can you know and not)
• Divorce article and discussion in class
• Importance of development in child