IECP Exam 2 – Study Guide and Exam Preparation Material
Experimental Design - correct answer ✔✔Researchers actively introduce an intervention or
treatment; called randomized clinical trial (RCT) in medical research *GOLD STANDARD*
Quasi-Experimental Design - correct answer ✔✔Involves an intervention but lacks
randomization and may or may not have a control group
Non-Experimental Design - correct answer ✔✔Researchers collect data without intervening or
introducing treatments/no manipulation of independent variables; sometimes called
observational research
Characteristics of True Experiments - correct answer ✔✔Intervention, Control, Randomization
Intervention - correct answer ✔✔The researcher does something to some participants;
introduces an intervention/treatment
Control - correct answer ✔✔The researcher introduces controls, including the use of a control
group
Randomization (Random Assignment) & why? - correct answer ✔✔The researcher assigns
participants to groups (experimental vs. control) at random. This is done to make the groups
equal with respect to all other factors EXCEPT receipt of the intervention.
Experimental Conditions - correct answer ✔✔1. Must be designed with sufficient intensity and
duration that effects might reasonably be expected
2. Attention must be paid to intervention fidelity/treatment fidelity = whether the treatment
was actually delivered and received as planned
,Control Conditions - correct answer ✔✔1. No intervention is used; control group gets no
treatment at all
2. "Usual care" = standard or normal procedures used to treat patients
3. An alternative intervention is used (ex. auditory vs. visual stimulation)
4. Use of a placebo/pseudo intervention = presumed to have no therapeutic value
5. Lower dose or intensity of treatment or only portions of it are administered
6. Delayed treatment
Blinding (Masking) - correct answer ✔✔The process of preventing those involved in a study of
having information that could lead to a bias
Advantages and Disadvantages of Experimental Designs - correct answer ✔✔Adv:
Most powerful for detecting cause and effect relationships (causal relationships)
Disadv:
Often not feasible or ethical
Expensive
Hawthorne effect = knowledge of being in a study may cause people to change their behavior
Two Categories of Quasi-Experimental Designs - correct answer ✔✔1. Nonequivalent control
group pretest-posttest
, 2. One-group pretest-posttest
Advantages and Disadvantages of Quasi-Experimental Designs - correct answer ✔✔Adv:
May be easier and more practical than true experiments
Disadv:
More difficult to infer causality
Usually there are several alternative rival hypotheses
Types of Non-Experimental Designs - correct answer ✔✔1. Correlational
2. Descriptive
Correlational Design - correct answer ✔✔Address cause-probing questions that cannot be
answered via manipulation (not possible or appropriate); can be prospective or retrospective
Non-experimenal
Two types of Correlational Designs - correct answer ✔✔1. Prospective
2. Retrospective
Correlation - correct answer ✔✔An interrelationship or association between two variables and
can be detected through statistical analysis
Prospective Design (Cohort Study) - correct answer ✔✔A correlational study in which a
potential factor in the present is linked to a hypothesized later outcome
Experimental Design - correct answer ✔✔Researchers actively introduce an intervention or
treatment; called randomized clinical trial (RCT) in medical research *GOLD STANDARD*
Quasi-Experimental Design - correct answer ✔✔Involves an intervention but lacks
randomization and may or may not have a control group
Non-Experimental Design - correct answer ✔✔Researchers collect data without intervening or
introducing treatments/no manipulation of independent variables; sometimes called
observational research
Characteristics of True Experiments - correct answer ✔✔Intervention, Control, Randomization
Intervention - correct answer ✔✔The researcher does something to some participants;
introduces an intervention/treatment
Control - correct answer ✔✔The researcher introduces controls, including the use of a control
group
Randomization (Random Assignment) & why? - correct answer ✔✔The researcher assigns
participants to groups (experimental vs. control) at random. This is done to make the groups
equal with respect to all other factors EXCEPT receipt of the intervention.
Experimental Conditions - correct answer ✔✔1. Must be designed with sufficient intensity and
duration that effects might reasonably be expected
2. Attention must be paid to intervention fidelity/treatment fidelity = whether the treatment
was actually delivered and received as planned
,Control Conditions - correct answer ✔✔1. No intervention is used; control group gets no
treatment at all
2. "Usual care" = standard or normal procedures used to treat patients
3. An alternative intervention is used (ex. auditory vs. visual stimulation)
4. Use of a placebo/pseudo intervention = presumed to have no therapeutic value
5. Lower dose or intensity of treatment or only portions of it are administered
6. Delayed treatment
Blinding (Masking) - correct answer ✔✔The process of preventing those involved in a study of
having information that could lead to a bias
Advantages and Disadvantages of Experimental Designs - correct answer ✔✔Adv:
Most powerful for detecting cause and effect relationships (causal relationships)
Disadv:
Often not feasible or ethical
Expensive
Hawthorne effect = knowledge of being in a study may cause people to change their behavior
Two Categories of Quasi-Experimental Designs - correct answer ✔✔1. Nonequivalent control
group pretest-posttest
, 2. One-group pretest-posttest
Advantages and Disadvantages of Quasi-Experimental Designs - correct answer ✔✔Adv:
May be easier and more practical than true experiments
Disadv:
More difficult to infer causality
Usually there are several alternative rival hypotheses
Types of Non-Experimental Designs - correct answer ✔✔1. Correlational
2. Descriptive
Correlational Design - correct answer ✔✔Address cause-probing questions that cannot be
answered via manipulation (not possible or appropriate); can be prospective or retrospective
Non-experimenal
Two types of Correlational Designs - correct answer ✔✔1. Prospective
2. Retrospective
Correlation - correct answer ✔✔An interrelationship or association between two variables and
can be detected through statistical analysis
Prospective Design (Cohort Study) - correct answer ✔✔A correlational study in which a
potential factor in the present is linked to a hypothesized later outcome
