Design strategies

Question 1

Group designs

Answer 1

Several subjs studied

Groups formed by investigator

Question 2

Between group designs

Answer 2

Separate groups of subjs formed and ea group receives only one condition

Question 3

Single-case experiments

Answer 3

Characterized by an investigation of a given individual, few individuals, or one group over time
One or a few subjs studied
Dependent measures administered over time
Manner in which the IV is implemented is examined in relation to the data pattern for the subj(s) over time

Question 4

Conditions of experimentation

Answer 4

Laboratory versus applied
Analogue versus clinical
Efficacious versus effectiveness

Question 5

Laboratory versus applied

Answer 5

Highly controlled settings that depart from conditions of everyday life
Versus
Real-world settings - what can be accomplished in everyday studies

Question 6

Analogue versus clinical

Answer 6

The extent to which research studies a phenomenon that is intended to resemble something that occurs in everyday life

Question 7

Efficacy versus Effectiveness

Answer 7

Efficacy = research that is directed to more controlled conditions of a lab; evaluates tx in controlled conditions. Can rule out threats to validity 
Effectiveness = intervention research in applied settings under conditions in which tx is usually administered. Greater vulnerability to threats to all types of validity but external

Question 8

Random selection versus random assignment

Answer 8

Selection occurs before assignment
Selection = equal probability that subjs w/in a population can be selected
Assignment = allocating chosen subjs to groups randomly - ensures grp equivalence

Question 9

Nuisance variables

Answer 9

those characteristics in which one is not interested but that, in principle, could infl the results
Random assignment ensures these variables will be distributed unsystematically

Question 10

Matching

Answer 10

Refers to grouping subjects together on the basis of their similarity on a particular characteristic or set of characteristics
Groups will not differ on that characteristic prior to tx

Question 11

Ways to accomplish matching

Answer 11

1. Identical pretreatment scores
2. Rank all of the subjs
3. Categorical variable such as age, gender

Question 12

Mismatching

Answer 12

Subjs matched first then randomly assigned to groups
Used in an attempt to equalize groups when random assignment is not possible
Regression to the mean is a concern when subjs selected bc of extreme scores

Question 13

Pretest-posttest control group designs

Answer 13

Essential feature = subjs tested before and after
Adv: controls for threats to validity
Disadv: pretest sensitization

R O1 X O2
R O3 X O4

Question 14

Posttest only

Answer 14

consists of a minimum of two groups and essentially is the same as the previous design except no pretest
No effect of pretest

R X O1
R O2

Less popular bc no pretest (need to know baseline functioning usually)

Question 15

Solomon four-group design

Answer 15

Purpose = evaluate effect of pretest 
Evaluate w two-way ANOVA
Group 1 = Pretest, intervention, post
Group 2 = Pretest, NO intervention, post
Group 3 = No pre, intervention, post
Group 4 = No pre, no inter, post

R O1 X O2
R O3 O4
R X O5
R O6

Question 16

Factorial designs

Answer 16

Allows for more than one IV to be examined
Need larger sample size
2x2 design
Within each variable, 2 or more conditions administered
Eg two variables (tp experience and type of tx) would consist of two conditions (experience versus lack; tx A versus tx B)
Reason = combined effects of two or more variables may be of interest

Question 17

Quasi experimental designs

Answer 17

Same as experimental designs but NOT randomly assigned
eg
nonR X O1
nonR X O2

Question 18

Multiple tx designs

Answer 18

Ea participant gets more than one tx
Different tx presented to ea subj – WITHIN subjects
Tx presented in different orders - to COUNTERBALANCE effects

Question 19

Cross over designs

Answer 19

Partway thru the experiment, subjs crossover to another experimental condition
Design used w 2 different tis

R O1 XA O2 XB O3
R O4 XB O5 XA O6

Question 20

Multiple tx counterbalanced design

Answer 20

Select a set of sequences in advance to and to assign subjs randomly to these sequences as they arrive to the experiment
Latin Square design
Each group has a different sequence that includes each of the 4 txs

Question 21

Considerations when using the designs

Answer 21

Order and sequence effects
Restrictions w various independent and dependent measures
Ceiling and floor effects

Question 22

Tx strategies

Answer 22

Tx package 
Dismantling 
Constructive
Parametric
Comparative-tx
Tx-moderator
Tx-mediator

Question 23

Tx package

Answer 23

Does tx produce therapeutic change
Requires:
Tx versus no-tx or waiting list control

Question 24

Dismantling

Answer 24

What components are necessary, sufficient, and facilitative of therapeutic change?
Requires:
2 or more tx grps that vary in the components of tx provided

Question 25

Constructive

Answer 25

What components or other txs can be added to enhance therapeutic change?
Requires:
2 or more tx groups that vary in components

Question 26

Parametric

Answer 26

What changes can be made in the specific tx to increase its effectiveness?
Requires:
2 or more tx groups that differ in one or more facets of the tx

Question 27

Comparative tx

Answer 27

Which tx is more or most effective for a particular problem?
Requires:
2 or more different txs for a given clinical problem

Question 28

Tx-moderator

Answer 28

What patient, family, or tp characteristics does tx depend on to be effective?
Requires:
Tx as applied separately to different types of cases, tps, etc.

Question 29

Tx-mediator

Answer 29

What processes occur in tx that affect w/in-session performance and that may contribute to tx outcome?

Question 30

Why use control groups?

Answer 30

Controls for threats to testing, hx, maturation, selection, etc.
No tx versus wait-list control - to show it wasn’t an effect of time; Ethics, recruitment, attrition
Nonspecific tx control grp - attn placebo
Instrument develop and assessment - construct validity