Chapter 4 Evidence-Based Patient Care

Question 1

Mean difference or weighted mean difference

Answer 1

Used to compare cases and controls when units of measurements are identical between studies

Question 2

Standard mean difference

Answer 2

Used to compare cases and controls where differences are normalized with respect to pooled standard deviation of the two groups
Can be used to compare different measurements

Question 3

Selection bias

Answer 3

-Type of bias in study design
-certain patients are preferentially enrolled into the study and may not represent population at large

Question 4

Channeling bias

Answer 4

-Type of bias in study design
-patients are steered into study arms by organizers based on preconceived notions
-mitigated by blinded randomization

Question 5

Interviewer bias

Answer 5

-Type of bias in study design
-investigators asks different questions of the patients, knowing which study arm they are in
-mitigated by double-blind design

Question 6

Hawthorne effect

Answer 6

-Type of bias in study design
-Subject may behave differently because he knows he is being observed
-mitigated by double-blind design

Question 7

Chronology bias

Answer 7

-Type of bias in study design
-study patients are compared to historical controls at a time when standard of care may have been different
-mitigated by prospective design

Question 8

Recall bias

Answer 8

-Type of bias in study design
-subjects may not remember their symptoms or exposures correctly
-mitigated by using objective data sources

Question 9

Transfer bias

Answer 9

-Type of bias in study design
-certain types of patients are more likely to be lost to follow-up
-also known as attrition bias
-mitigated by careful plan to follow-up with patients

Question 10

Performance bias

Answer 10

in cases where the intervention involves a procedure, possible for different operators to perform the procedure differently

Question 11

Publication bias

Answer 11

-Type of bias in study design
-journals tend to report positive findings more readily than negative findings

Question 12

p-value

Answer 12

Probability that the results found in the study could be a result of pure chance

Question 13

Odds ratio

Answer 13

used in case-control studies when prevalence is not known

Question 14

Grading of Recommendations Assessment, Development and Evaluation (GRADE)

Answer 14

-Code A (high quality, further research is unlikely to change our confidence in the estimate of effect), Code B (moderate quality, further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate), Code C (low, further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate), Code D (very low (any estimate of effect is very uncertain
-Assess studies by: study design, study quality (bias, flaws), consistency (subgroup analysis), directness (population differences, use of surrogate markers, no direct comparison), strength of association, evidence of dose response gradient, when reasonable confounding would have pushed effect in one direction

Question 15

Evidence-based Practice Center (EPC) approach

Answer 15

-Supported by Agency for Healthcare Quality and Research (AHRQ)
-Similar to GRADE
-Assesses domains of: risk of bias, consistency, directness, precision

Question 16

Precision

Answer 16

Refers to lack of random errors in measurement

Question 17

Validity

Answer 17

Refers to lack of systematic error

Question 18

Internal validity

Answer 18

Relates to ability of study’s interventions to explain the findings

Question 19

External validity

Answer 19

Refers to the ability of the study to generalize to other populations

Question 20

Strength-of-Recommendation Taxonomy (SORT)

Answer 20

Code A: consistent, good-quality patient-oriented evidence
Code B: Inconsistent or limited-quality patient-oriented evidence
Code C: consensus, disease-oriented evidence, usual practice, expert opinion, or case series for studies of diagnosis, treatment, prevention, or screening

Question 21

Clinical practice guidelines (CPG)

Answer 21

-Statements that include recommendations intended to optimize patient care that are informed by a systematic review of evidence and an assessment of the benefits and harms of alternative care options
-Typically includes a systematic review of the research evidence, and set of recommendations

Question 22

National Guideline Clearinghouse (NGC)

Answer 22

Public resource maintained by the AHRQ, to be included guidelines must follow Institute of Medicine (IOM) definition of CPG and include systematic review and assessment of benefits/harms

Question 23

CPG algorithm

Answer 23

Action (perform specific action)
Conditional (carry out action based on defined criteria)
Branch (direct flow to one or more additional steps)
Synchronization (converge paths back from branches to a common outcome/end point)

Question 24

National Guideline Clearinghouse practice guidelines levels of evidence and grades of recommendation

Answer 24

-Page 82
-Grades of Recommendations are based on the Levels of Evidence

Question 25

Comparative Effectiveness Research (CER)

Answer 25

Key elements are:
-Direct comparisons of active treatments
-Study patients, clinicians, and interventions that are representative of usual practice
-Focus on helping patients, clinicians, and policy makers to make informed choices

Question 26

Appropriate Use Criteria

Answer 26

-Variation on clinical practice guidelines, but differ in various ways (including rely more on expert opinion)

Question 27

Moulding multistep process for adoption of clinical changes

Answer 27

-Described in 1999
-Knowledge: individuals exposed to innovation
-Persuasion: individual seeks more information about innovation
-Decision: decide whether or not to adopt or reject innovation
-Implementation: tries out innovation
-Confirmation: finalizes decision to continue using innovation

Question 28

Macdonald 5 Stages of Assessment

Answer 28

-Step 1: Assessment of Practitioners’ Stage of Readiness to Change
-Step 2: Assessment of Specific Barriers to Guideline Use
-Step 3: Determination of Appropriate Level of Intervention
-Step 4: Design of Dissemination and Implementation Strategies
-Step 5: Evaluation

Question 29

Knowledge-to-Action Framework

Answer 29

-As adapted for implementation of Best Practice Guidelines
1) Identify the problem
2) Adapt knowledge, tools, and resources to local context
3) Assess barriers and facilitators to knowledge use
4) Select, tailor, and implement interventions
5) Monitor knowledge use
6) Sustain knowledge use

Question 30

Information retrieval

Answer 30

-process of dinging material of an unstructured nature that satisfies an information need from within large collections
-users start with information needs form which they compose queries, search a body of knowledge known as a corpus for individual documents, the individual documents are tokenized and stored into an index for rapid retrieval

Question 31

Medical Subject Heading (MeSH) dictionary

Answer 31

Assigned by independent indexers from the National Library of Medicine and are hierarchical

Question 32

Stopwords

Answer 32

words that are deliberated excluded from an index

Question 33

Tokenization

Answer 33

Process of breaking up document into individually searchable items