Evidence-based practice

Question 1

Evidence-based practice in SLT involves

Answer 1

integrating the best research evidence with clinical expertise and patient values.

Question 2

3 pillars

Answer 2

scientific evidence, clinical expertise, patient values

Question 3

goal of EBP

Answer 3

to make informed clinical decisions and provide effective interventions

Question 4

history of EBP

Answer 4

dates back to the mid-19th century, with its modern form emerging in the early 1990s in Canada, driven by demands for accountability in service provision.

Question 5

Total Evidence and Knowledge Approach emphasises

Answer 5

the use of a broad range of evidence and knowledge to support the evaluation of speech-language pathology treatments and clinical decisions.

Question 6

TEKA encourages

Answer 6

therapists to consider various forms of evidence, including research-based, patient-based, and practice-based evidence.

Question 7

With TEKA, it’s important to be aware of:

Answer 7

• over-reliance on certain forms of evidence, such as research efficacy studies, while neglecting patient- and practice-based evidence.
• eminence-based practice: places a strong emphasis on the opinions and recommendations of experts or authorities in the field, often based on their reputation, status, or experience.
• habit-based practice
• convenience-based approaches

Question 8

Levels of evidence provide

Answer 8

a hierarchy for research designs based on their potential for bias, with randomized controlled trials (RCTs) often considered the gold standard.

Question 9

Issues with levels of evidence to consider

Answer 9

limited availability of RCTs in many areas of speech and language therapy, generalizability concerns, and biases towards manualized interventions must be considered.

Question 10

Research evidence should be based on factors like

Answer 10

Reliability and validity

Question 11

Reliability

Answer 11

the consistency and stability of measurements or assessments over time and across situations. It ensures that repeated measurements produce similar results and helps prevent random errors.

Question 12

Validity

Answer 12

assesses the accuracy and truthfulness of measurements, ensuring that a measurement tool or instrument accurately measures what it is intended to measure. It is crucial for obtaining meaningful and relevant information in healthcare.

Question 13

Sensitivity

Answer 13

Sensitivity, also known as the true positive rate or the recall rate, measures the ability of a diagnostic test to correctly identify individuals who have a specific condition or disease.

Question 14

Importance of sensitivity

Answer 14

Sensitivity is crucial when the consequences of missing a true positive (i.e., failing to identify a person with the disease) are significant. In healthcare, a highly sensitive test is desirable when early detection and intervention are critical to improving patient outcomes.

Question 15

Calculation of sensitivity

Answer 15

Sensitivity is calculated as the number of true positives (individuals correctly identified as having the condition) divided by the sum of true positives and false negatives (individuals with the condition incorrectly classified as not having it). Mathematically, it can be expressed as Sensitivity = True Positives / (True Positives + False Negatives).

Question 16

Specificity

Answer 16

Specificity measures the ability of a diagnostic test to correctly identify individuals who do not have a specific condition or disease.

Question 17

Importance of specificity

Answer 17

Specificity is important when a false positive result (i.e., identifying someone as having the condition when they do not) can lead to unnecessary medical procedures, costs, and anxiety. In some cases, specificity may be prioritized over sensitivity.

Question 18

Calculation of specificity

Answer 18

Specificity is calculated as the number of true negatives (individuals correctly identified as not having the condition) divided by the sum of true negatives and false positives (individuals without the condition incorrectly classified as having it). Mathematically, it can be expressed as Specificity = True Negatives / (True Negatives + False Positives).

Question 19

Psychometrics

Answer 19

the application of statistics to measure human behavior. Psychometricians use specialized statistical tools to create valid assessments, and speech-language pathologists use these for language-related assessments.

Question 20

Standardized assessments

Answer 20

• have structured administration and scoring procedures, ensuring consistency. - They involve interpreting scores based on a representative sample of similar individuals.
  are important for consistent, unbiased assessments, supporting clinical judgment, and guiding treatment. They also help in measuring treatment outcomes and forming best practice recommendations.
• Standardized assessments provide various scores, such as standard scores, T-scores, and percentile ranks, making interpretation and comparison easier.
• Converting raw scores to standard scores allows comparing a client’s performance to the normative sample, ensuring accurate assessment and interpretation.

Question 21

Standardised scores and the normal curve

Answer 21

Standard scores are based on normative data and transformed to create a normal curve with a specific mean and standard deviation.
Mean is the 50th percentile, representing the average score.
Standard deviations above the mean correspond to higher percentiles, while those below indicate lower percentiles.
For normally distributed constructs, one standard deviation below the mean corresponds to the 16th percentile.

Question 22

Basal and ceiling rules

Answer 22

Basal rules determine where to start a test, typically at a point where 95% of children of that age respond correctly.
Ceiling rules indicate when to stop testing, preventing administering items that exceed the client’s ability to respond

Question 23

Confidence Intervals:

Answer 23

Confidence intervals account for measurement error inherent in clinical tests.
They provide a range of scores that likely include the client’s true score with 90% or 95% likelihood.
A narrower confidence interval indicates a more precise score.

Question 24

Standard Error of Measurement

Answer 24

The standard error of measurement (SEM) estimates measurement error in a test.
SEM is inversely related to reliability; higher reliability results in a smaller SEM.
It’s used to create confidence intervals and interpret test scores accurately

Question 25

Quality Norms:

Answer 25

Normative samples should be large enough for stable estimates of the mean and standard deviation.
The sample should be representative of the population for which the test is intended.
Factors known to influence test scores should be adequately represented.
Norms should be current, as norms may shift over time due to societal changes.

Question 26

Not All Assessments Require Norms:

Answer 26

Criterion-referenced tests are keyed to external standards or criteria, such as curriculum standards, and do not rely on norms.

Question 27

Reliability:

Answer 27

Reliability assesses the dependability of a test.
Internal consistency reliability measures the correlation between items to determine if they measure the same construct.
Test-retest reliability estimates stability by comparing scores from two test administrations to the same examinee.
Reliability is important to ensure that a test consistently measures what it’s supposed to measure

Question 28

Validity

Answer 28

Validity assesses whether a test measures what it is intended to measure.
Evidence of validity can be provided through various approaches.
Concurrent validity involves comparing a new test with established tests to demonstrate correlations.
Convergent validity shows high correlation with other tests measuring the same construct.
Divergent validity demonstrates lower correlation with tests measuring different constructs.
Validity is not a single number but a collection of evidence supporting the test’s intended use