Research strategies & Design Comps study guide

steps in EBP process

Step 1: Framing the Clinical Question

Step 2: Finding the Evidence

Step 3: Assessing the Evidence

Step 4: Making the Clinical Decision

evidence-based practice

clinical decision making that integrates the best available research with clinical expertise and patient characteristics and preferences

EBP step 1

PICO

P: patient, population, or problem (how would you describe a group of patients similar to yours?)

I: intervention prognostic factor, exposure (What you plan to do for your patient or the group?)

C: Comparison (What is the main alternative to compare with the the intervention)

o: outcome what you would like to measure (what you hope to accomplish, measure, improve, or affect)

levels of evidence based practice

1a: well-designed meta analysis of >1 randomized controlled trial

1b: well designed randomized controlled study

2a: well designed controlled study without randomization

3: well designed non-experimental studies (correlational and case studied)

4: expert committee report, consensus conference, clinical experience of respected authorities

internal validity

the extent to which you can claim that no other variables except the one you're studying caused the result.

treatment (iv manipulation) --> behavior change (DV change)

have you controlled everything within the experiment so that the only change seen is because of the x-variable?

external validity

the extent to which your research results apply to more than just the participants in your experiment, can this be done outside my study?

independent variable

causes change, variable being manipulated

"what is changed"

dependent variable

result of effect of change, what is measured

variable that is being tested

"what is observed"

confounding variables

factors that cause differences between the experimental group and the control group other than the independent variable

group designs

one or more groups exposed to IV, average performance on DV examined, determining relationship between IV and DV for group

types of group design

between subject and within subjects

between subjects

different groups under conditions, they are exposed to different levels of IV

Bivalent, Multivalent, and Parametric experiments

bivalent experiments

experimental group: one group is exposed to treatment or IV

control group:

multivalent experiments

different groups expoed to different values of IV

parametric experiments

several groups expoed to different values of IV in different combinations, and can also be compared to control group

within subject design

same group under direct conditions

major considerations for experimental studies

Control of sequencing effect: participation in earlier condition affects performance in following condition(s)

order effect, carryover effect, reduce sequencing effect, mixed designs

order effect

performance improves (practice) or decreases (Fatigue) across experiment

carryover effect

influence of one condition on the next

to reduce sequencing effect

sequence randomization- presentation of conditions in random order

counterbalancing- control and measure sequencing effects by random assignment to all possible sequences

if sequencing can be controlled

well-within subject design is powerful (As subjects act as their own control group)

mixed design

compares both between and within subjects, may measure effects of 1 IV between-subjects and other IV within-subjects

control techniques for both with-in subject and between subject designs are important

typical group design

performance of 2 groups measured before and after presentation of IV (Tx) to experimental group

true experimental designs

explores cause and effect, easy to spot bc of randomization (pretest-posttest control group)

quasi-experimental designs

two or more groups, no random assignment extraneous variables not easily controlled

single-subject design types

ABAB withdraw design

if testing 2 forms of tc, (B,C) - ABACA

multiple baseline designs

changing criterion design

alternating tx design

interaction design

ABAB withdraw design

goal is to demonstrate clear relationship between application of therapy and behavioral change

Baseline (A1)

Treatment (B1)

Treatment withdraw (A2)

Treatment reinstated (B2)

ABACA

If testing 2 forms of TX, may result in carry-over effect

best to counterbalance if have more then 1 subject

some subjects: ABACA; other subjects ACABA

multiple baseline designs

Designs used when it is not possible or ethical to employ a treatment reversal period or should not be reversed. In this design, baselines are established for two (or more) behaviors, treatment is introduced for one behavior, and then treatment is introduced for the second behavior as well. By observing changes in each behavior from period to period, one may draw conclusions about the effectiveness of the treatments.

this can be across behaviors, participants, or settings

changing criterion designs

evaluates effects of tx that is applied in a graduated fashion to a single targeted behavior (Requires careful manipulation of: length of phases, magnitude of criterion changes, and umber of criterion changes)

alternating Tx designs

2 txs, A and B, are alternated randomly as they are applied to a single subject

interaction design

relative to tx package (BC)

to what degree to separate components contribute to improvement? Does addition of component (C) to a tx package (B) facilitate effectiveness??

descriptive statistics

tell us about data

inferential statistics

tell us about group differences