Levels of Evidence
This is the HIGHEST level of evidence, synthesizing multiple high-quality RCTs.
What is a Systematic Review or Meta-analysis?
A research design in which data are collected at one point in time.
What is a cross-sectional study?
This section is usually the last one written but appears first in the paper.
What is the Abstract?
The hypothesis stating there is no difference between groups.
What is the null hypothesis?
This variable is manipulated or assigned by the researcher.
A research design in which data are collected at one point in time.
What is a Cross-sectional study?
This design randomly assigns participants to intervention and control groups.
What is a randomized controlled trial?
This section presents findings without interpreting them.
What is the Results section?
Which hypothesis is directional?
A. Participants in a home safety program will have fewer falls than the controls.
B. Participants in a home safety program will differ in the #of falls compared the controls.
What is hypothesis A?
Researchers record participants' blood type (A, B, AB, or O). What type of variable is blood type?
What is a nominal (or categorical) variable?
This level of evidence is generally considered the weakest when making clinical decisions.
What is Expert Opinion?
Researchers follow participants over several years to observe changes.
What is a longitudinal study?
This section describes participants, procedures, and statistical analyses used.
What is the Methods section?
Rejecting a true null hypothesis is called this type of error.
What is a Type I error?
Participants rate their pain as none, mild, moderate, or severe. What type of variable is this?
What is an ordinal variable?
Researchers describe the outcomes of 15 patients who received the same occupational therapy intervention. There is no comparison group or randomization. According to many levels-of-evidence hierarchies, this study represents what level of evidence?
What is Level IV?
This type of study design does not include a comparison or control group, making it difficult to determine whether the intervention alone caused the observed changes.
What is a one-group pretest-posttest design?
This section should acknowledge weaknesses such as a small sample size or limited generalizability.
What is the Discussion section?
This type of hypothesis predicts only that a difference will occur, but not the direction of the difference.
What is a non-directional hypothesis?
Researchers are concerned that participants' age may affect balance scores, regardless of the intervention. Age is acting as what type of variable?
What is a confounding (or extraneous) variable?
Researchers compare the outcomes of patients treated at two rehabilitation hospitals. One hospital routinely uses constraint-induced movement therapy, while the other provides standard therapy. Participants are not randomly assigned to hospitals.
What is a Quasi-Experimental design?
A researcher interviews 15 stroke survivors to understand their experiences returning to work.
What is Qualitative Research?
Name the section:
"Forty-five participants completed the intervention. Mean balance scores improved significantly (p = .02)."
What is the Results section?
What type of hypothesis is this?
Researchers predict that adults with arthritis who receive joint protection education will differ in pain scores from those receiving usual care.
What is a non-directional hypothesis?
A researcher is studying whether sleep quality predicts academic performance among OT students while controlling for age and GPA.
What is academic performance