NPTE Research and EBP

A comparison of the effects of exercise in water, on land, or combined on the rehabilitation outcome of patients with intra-articular anterior cruciate ligament reconstructions revealed that less joint effusion was noted after 8 weeks in the water group. What is the appropriate statistical test to compare the girth measurements of the three groups?

1. Analysis of covariance.

2. Spearman's rho.

3. Chi square.

4. ANOVA.

4. ANOVA.

ANOVA is a parametric statistical test used to compared three or more treatment groups (in this example, in water, on land, or combined exercise groups) on a measure of the dependent variable (joint effusion girth measurements) at a selected probability level

A researcher uses a group of volunteers (healthy college students) to study the effects of therapy ball exercises on ankle ROM and balance scores. Twenty volunteers participated in the 20-minute ball exercise class three times a week for 6 weeks. Measurements were taken at the beginning and end of the sessions. Significant differences were found in both sets of scores and reported at the local physical therapy meeting. What is the MOST accurate interpretation of this study and its results?

1. The reliability of the study was threatened with the introduction of systematic error of measurement.

2. The Hawthorne effect may have influenced the outcomes of the study.

3. The validity of the study was threatened with the introduction of sampling bias.

4. Therapy ball exercises are an effective intervention to improve ankle stability after chronic ankle sprain

3. The validity of the study was threatened with the introduction of sampling bias.

The investigator used a sample of convenience and therefore introduced systematic sampling error (a threat to validity). Random selection of subjects would improve the validity of this study.

A group of institutionalized elderly was examined for balance instability and fall risk using a standardized test, the Performance-Oriented Mobility Assessment (POMA). The test-retest reliability of total test (POMA-T) and the subtests, balance subtest (POMA-B) and gait subtest (POMA-G) varied between 0.77 and 0.86. The interrater reliability values ranged from 0.80 to 0.93. What is the therapist's correct interpretation of these findings?

1. Overall, the test demonstrated moderate reliability.

2. The test demonstrated moderate reliability for test-retest and good reliability for interrater comparisons.

3. The test demonstrated poor reliability for test-retest and moderate reliability for interrater comparisons.

4. Overall, the test demonstrated good reliability.

4. Overall, the test demonstrated good reliability.

Reliability coefficients above 0.75 demonstrates good reliability. This test demonstrated good reliability both for test-retest and interrater comparsions

A team of researchers investigates the use of constraint-induced movement therapy on patients with chronic stroke (> 1 year poststroke) using a multicenter randomized controlled trial (RCT). What are the specific characteristics of this type of research design?

1. A sample of convenience for the intervention group.

2. Alternating experimental and control conditions for a subject.

3. Random assignment to an experimental or control group.

4. Random assignment to matched cohort groups.

3. Random assignment to an experimental or control group.

An RCT uses randomization process to assign subjects to either an experimental group(s) or a control(comparison) group. Subjects in the experimental group receive the intervention and are then compared with subjects in the control group who do not receive the intervention. A large multicenter RCT study with large numbers of patients provides the highest level of scientific rigor and evidence.

A group of researchers investigated the effect of tai chi on perceived health status in older, frail adults. The subjects were 269 women who were older than 70 years of age and recruited from five independent senior living facilities. Participants took part in a 48-week single-blind RCT. Perceived health status was measured by five pretrained testers using the Sickness Impact Profile (SIP). The researchers found significant perceived health benefits. Which of the following is an accurate conclusion regarding the design of this study?

1. Generalizability to a larger population of elderly women.

2. Errors in reliability due to the number of testers.

3. Errors in validity due to the selection of the outcome measure.

4. Limited findings on the effects of tai chi exercise in the frail elderly.

1. Generalizability to a larger population of elderly women.

This study provides important findings on the effects of tai chi in elderly women. It is an RCT with a large number of subjects from multiple centers. Thus it has good generalizability to a population of elderly women. The SIP is a gold standard instrument with extensive testing and established validity and reliability

What is the BEST evidence to determine orthotic intervention to prevent inversion ankle sprains?

1. Meta-analyses of cohort studies.

2. Systematic reviews of randomized controlled trials.

3. Meta-analyses of multiple case studies.

4. Randomized double-blind controlled trials.

2. Systematic reviews of randomized controlled trials.

Systemic review including meta-analysis of RCT provides the best research evidence of effectiveness of an intervention

A group of 37 adolescent girls ages 12 and 13 were recruited into a study on developmental changes in bone density. Bone mineral density (BMD) was measured on admission into the study and every 4 months thereafter for a period of 3 years. The investigators concluded that BMD peaked at the age of 14, with a standard deviation of 7 months. What is the category of this research?

1. Randomized controlled trial.

2. Case control study.

3. Between-subject study.

4. Prospective cohort study.

4. Prospective cohort study.

This is a prospective (forward-in-time) study. A group of participants (cohort) with a similar condition is followed for a defined period of time. This is a cohort study

A group of 10 patients is recruited into a study investigating the effects of relaxation training on blood pressure (BP). One group of patients is scheduled to participate in a supervised cardiac rehabilitation program that includes relaxation training three times a week for 12 weeks. The other group of patients is instructed to perform activities as usual. At the conclusion of the study, there was no significant difference between the groups; BP decreased significantly in both groups. What is the MOST accurate interpretation of this study?

1. The rehabilitation group was not properly monitored.

2. Both groups had BPs initially so high that reductions should have been expected.

3. The activities of the nonrehabilitation group were not properly monitored and may account for these results.

4. Cardiac rehabilitation is not effective in reducing BP.

3. The activities of the nonrehabilitation group were not properly monitored and may account for these results.

To ensure adequate control, the researcher should attempt to remove the influence of any variable other than the independent variable in order to evaluate its effect on the dependent variable. In this study, the investigator did not adequately investigate the usual activities of the control group. The small number of subjects may also have contributed to the lack of significance.

A therapist investigated the accuracy of pulse oximetry estimates during exercise. Correlational analysis measured the strength of the relationship between two types of ear probe—equipped pulse oximeters during heavy cycle exercise under hypoxic conditions. The investigator found measured arterial oxyhemoglobin saturation (%HbO2) levels to have a correlation of 0.89 at high saturation but only 0.68 at low saturation levels. How should the therapist interpret these results?

1. During heavy exercise, oxygen saturation levels should be interpreted cautiously.

2. Both devices are highly accurate at all saturation levels.

3. Accuracy of the measurements increases at higher saturation levels.

4. Both devices are only moderately accurate.

3. Accuracy of the measurements increases at higher saturation levels.

The result of the study indicates that the correlation between the two types of oximeters was high when oxygen saturation levels were high (0.89), but only moderate (0.68) at low oxygen saturation levels

A group of researchers utilized meta-analysis to identify the evidence for aerobic fitness exercises in the management of fibromyalgia. Thirteen randomized, controlled trials (RCTs) and three controlled clinical trials (cohort studies and case control studies) were selected. What is the main difference between the two types of trials?

1. Duration of the studies.

2. Use of multiple centers versus single center trials.

3. Length of the studies.

4. Use of randomization of subjects.

4. Use of randomization of subjects.

The main difference between the two types of trials is randomization of subjects into experimental and control groups (RCT)

Nominal Scale

a scale in which objects or individuals are assigned to categories that have no numerical properties

Nominal Scale Examples

Gender

Race

Interval Scale

a scale of measurement in which the intervals between numbers on the scale are all equal in size

Ordinal Scale Examples

GPA

MMT

Ordinal Scale

a scale of measurement in which the measurement categories form a rank order along a continuum

Interval Scale Examples

Temperature

IQ

Ratio Scale

a quantitative scale of measurement in which the numerals have equal intervals and the value of zero truly means "nothing"

Ratio Scale Examples

Gonimetry

Scales for Height and Weight

Control Group

the group that does not receive the experimental treatment.

Experimental Group

the group in an experiment that receives the variable being tested

Interrater Reliability (IRR)

a measure for the extent to which two or more raters of the same behavior or event are in agreement with what they observed

Intrarater Reliability

comparison of results by an individual using a measurement tool at two or more different times

Test-Retest Reliability

a method for determining the reliability of a test by comparing a test taker's scores on the same test taken on separate occasions

Good Reliability

>0.75

Moderate Reliability

0.50-0.75

Poor Reliability

<0.50