Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IPAP Research & Evaluation > Research Evaluation Exam > Flashcards

Research Evaluation Exam Flashcards

1
Q

Physician Assistant Competencies:

Patient care, Professionalism, Systems-based practice.

A

Reasons for Research Evaluation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Make decisions about diagnostic and therapeutic interventions based on patient information and preferences, current scientific evidence, and informed clinical judgment.

A

Patient Care

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Commitment to excellence and on-going professional development.

A

Professionalism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Partner with supervising physicians, health care managers, and other health care providers to assess, coordinate, and improve the delivery and effectiveness of health care and patient outcomes.

A

Systems-based practice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  • Analyze practice experience and perform activities using a systematic methodology.
  • Locate, appraise, and integrate evidence from scientific studies - Study designs and statistical methods
  • Utilize information technology to manage information, access medical information, and support their own education
  • Recognize and appropriately address personal biases,
A

Practice-based Learning and Improvement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The practice of health care in which the practitioner systematically finds, appraises, and uses the most current and valid research findings as the basis for clinical decisions.

A

Evidence based practice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Results in the best possible outcome for your patients.

A

Integration of research evidence and clinical experience

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Original study design

A

Primary Literature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  • Databases Point of Care resources
  • Up To Date
  • MD Consult
  • Epocrates
  • Lexicomp
A

Secondary Literature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  • Primary (Analytic) Studies
  • Experimental
  • Observational Secondary (Integrative) Studies
A

Medical Literature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Those that report original research.

  1. Experimental
  2. Observational
A

Primary (Analytic) Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

An intervention is made or variables are manipulated.

Example: experiment, randomized controlled trial, non-randomized controlled trial

A

Primary (Analytic) Studies Experimental

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

No intervention is made and no variables are manipulated.

Example: cohort, case-control, cross-sectional, descriptive, surveys, case reports, etc.

A

Primary (Analytic) Studies Observational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  1. Author’s peers and recognized researchers in the field read and evaluate a paper (article) submitted for publication.
  2. Articles/scholarly journals accepted meet the discipline’s expected standards of expertise and passed through this review process.
A

Peer Review

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
  1. Authors ->
  2. Authors submission ->
  3. Editor ->
  4. Peers ->
  5. Peer comments ->
  6. Editor roll-up comments ->
  7. Author -> Repeat process
A

Peer Review Process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A journal’s impact factor for a particular year

A

Impact score

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Total number of times its articles were cited during the two previous ➗ Total number of citable articles in the journal during those two years.

A

Calculation of Impact Score

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Sources for Literature (credible)

  • PubMed
  • Google Scholar
  • UpToDate
  • Medscape
  • DoD/Va Clinical Practice Guidelines
A

Finding Literary Sources

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control health problems.

A

Epidemiology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  • Reduce morbidity and mortality from disease
  • Extent of disease
  • Evaluate and develop preventative and therapeutic care
  • Develop policy
A

Objectives of Epidemiology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Critical to public health and clinical practice to determine information

A

Clinical Practice & Epidemiology: Importance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Multi-step process:

  • Determine whether an association exists between an exposure or an outcome.
  • If there is an association…is it causal?
  • Derive appropriate inferences about a possible causal relationship from the patterns are found.
A

Epidemiologic approach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The branch of statistics that deals with data relating to living organisms.

A

Biostatistics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Tools of statistics to help answer pressing research questions in medicine, biology, and public health

A

Importance of Biostatistics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Methods, Materials & Patients:

What methods are used to evaluate medical literature?

A
  • Study design
  • Subject selection procedures
  • Method of measurement
  • Description of analytic techniques
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q
  • Read only what is interesting and useful
  • Scan the article to gain a quick overview
  • Concentrate on the methods section
  • Reserve the right for final judgment
A

Tips for Evaluating Medical Literature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q
  • Observes associations
  • Show patterns of disease occurrence
  • Helps to generate hypotheses
A

Descriptive research

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q
  • Analyzes associations
  • Investigates relationships
  • Tests hypotheses
A

Analytic research

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q
  • Descriptive epidemiologic studies reveal the patterns of disease occurrence in human populations.
  • Provide general observations concerning the relationship of disease to basic characteristics. IE: Person, Place, Time
A

Descriptive Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Examples: Case Reports Clinical Series Populations (Ecologic Studies)

A

Descriptive Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Descriptive Study or Analytic Study?

Alerting the medical community to what types of persons are at risk for a new…..or old disease?

A

Descriptive Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Descriptive Study or Analytic Study?

Assisting in the rational planning of health and medical care needs:

I.e.. How many PAs do we need in the field?

A

Descriptive Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Descriptive Study or Analytic Study?

Provide clues to disease etiology and questions or hypotheses for further study.

A

Descriptive Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Attempt to provide insight into etiology or find/ determine better patient outcomes.

  • Experimental
  • Observational
A

Explanatory Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Has an active intervention from the investigator.

A

Explanatory Studies - Experimental

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Examples of _____________

  • Controlled trial
  • Clinical trial
  • Educational intervention
  • Healthcare trial
  • Intervention trial
A

Explanatory Studies - Experimental

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Investigator observes nature

A

Explanatory Studies - Observational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Examples of _____________

  • Case-control
  • Follow-up
  • Cross-sectional
  • Cohort or follow up
A

Explanatory Studies - Observational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Descriptive Study or Analytic Study?

  • Experimental
  • Clinical Trial
  • Community Trial
  • Educational Intervention
A

Analytic Study

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Descriptive Study or Analytic Study?

  • Observational
  • Case-control
  • Cohort (follow up)
  • Cross-sectional
A

Analytic Study

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
  • A narrative in the professional literature that identifies a single incident and discusses pertinent factors related to the patient
  • Brings a novel or unusual patient to the attention of colleagues
  • Information is preliminary and unrefined in terms of research methodology
A

Case Report

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

As the name implies, this type of study analyzes a number of individual cases that share a commonality

Usually relatively low numbers of subjects

A

Case Series

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q
  • Examine adverse events or effects - Catalog new diseases or outbreaks - Determine the feasibility or safety of a new treatment or intervention - Discuss the potential efficacy of a new treatment
A

Case Series are used to:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Case reports and case series lack?

A

Sufficient methodological rigor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q
  • Data does not necessarily extrapolate to larger populations - Evidence may be circumstantial - Confounding factors may be present - But – both typically indicate the need for further study
A

Case reports and case series lack…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q
  • Examine the relationship between exposures and diseases as measured in a population r - Utilizing data from surveys or registries - Followed by an analytic study to see if the association holds true in individuals.
A

Descriptive study design - Ecologic Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Is a type of bias specific to ecological studies. Occurs when relationships that exist for groups are assumed to also be true for individuals.

A

Ecological Fallacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Attempt to provide insight into etiology or find/ determine better patient outcomes: - Experimental - Observational

A

Explanatory Studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Has an active intervention from the investigator. Examples: - Controlled trial - Clinical trial - Educational intervention - Healthcare trial - Intervention trial

A

Explanatory Studies - Experimental

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Investigator observes nature. Examples: - Case-control - Follow-up - Cross-sectional - Cohort or follow up

A

Explanatory Studies - Observational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q
  • Examines the relationship between outcomes and other variables of interest at one particular time. - Determines prevalence (% of population) not incidence (rate) - Enrolls a large number of individuals - Cannot show causality, does not separate cause/effect - Does not establish a temporal relationship between risk factors and disease because they are measured at the same time
A

Cross-sectional studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Strengths of __________ - Can assess multiple outcomes and exposures simultaneously - Can be completed quickly - Data generated can lead to further studies - Can generate prevalence

A

Cross-sectional studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Limitations of __________ - No time reference: “Snapshot In Time”- like looking at a photograph - Only useful for common conditions - Cannot calculate incidence, it is a prevalence study Results are dependent on the study population

A

Cross-sectional studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q
  • Studies specific condition (cases) and compares with people who do not have the condition (controls). - The researcher looks back to identify factors or exposures - Design may follow a case-series (as a retrospective look at causes). - Captures the cause and effect relationship by comparing the frequency of a risk factor among those how are exposed and not-exposed.
A

Case-control studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Strengths of __________ - Good for studying rare outcomes - Can evaluate many exposures - Ideal for initial, explanatory idea - Simple & fast – we already know the outcomes - Efficient-no waiting for outcome to occur - Inexpensive

A

Case-control studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Limitations of __________ - Single outcome - High risk for bias - High risk for confounding variables - Other factors may exist those influence outcomes - Can’t determine the prevalence - Temporality - Can’t make causal interpretations - Can’t determine the incidence - Can’t calculate Relative risk

A

Case-control studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Selection Bias: the inappropriate selection of cases or controls.

A

Case-control studies bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

__________ bias: Can be selected from a variety of sources: Hospitals, Clinics, Registries. If cases are selected from a single source, and risk factors from that facility may not be generalizable to all patients with that disease.

A

Case-control studies Selection bias - Case

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

__________ bias: come from the same reference population that cases are derived from. An inappropriate control group can have the opposite effect and obscure an important link between disease and its cause

A

Case-control studies Selection bias - Control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

__________ bias: Recall Bias (Subject Bias) is the main form of information bias in case-control studies. Occurs when there is a differential recall of exposure between cases and controls.

A

Case-control studies Information Bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

__________ bias: Occurs when the researcher/observer evaluates cases vs controls differentially.

A

Case-control studies Researcher/Observer Bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

__________ bias: Arises when case subjects who think they have been exposed to responds at a higher rate to controls.

A

Case-control studies Voluntary Reponses Bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

__________ is the process of selecting the controls so they are similar to the cases in certain characteristics, such as age, race, sex, socioeconomic status, and occupation. - Individual - Group-based

A

Control Biases: Matching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Individual or Group Matching? For each case selected for the study, a control is selected who is similar to the case in terms of the specific variable

A

Control Biases: Matching Individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Individual or Group Matching? Select controls with a certain characteristic that is identical to the proportion of cases with same characteristic.

A

Control Biases: Matching Group-Based

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q
  • If you select too many matching characteristics it is difficulty to find an appropriate control. - You lose the ability to study a matched variable.
A

Control Bias: Problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Offers independent estimates of exposure among different samples of non-cases. Increases strength of the study.

A

Control Bias: Mutliple Controls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Case-Control Study: __________ A variant of a case-control study Each case becomes their own individual control Used for transient exposures during a discrete occurrence

A

Case-Control Study: Case-crossover

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Case-Control Study: __________ Large cohort, large enrollment studies Controls are a sample of individuals who are at risk for the disease/outcome at the time each case of the disease develops.

A

Case-Control Study: Nested

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Case-Control Study: __________ Same as nested case-control design, expect controls are randomly chosen from the cohort at the beginning of the study

A

Case-Control Study: Case-Cohort

71
Q

a group of people who share a common characteristic or experience and all remain in the group for a period of time

A

Cohort

72
Q

a group of people who share a common characteristic or experience and all remain in the group for a period of time

A

Cohort Study

73
Q

identify a group of patients who are already taking a particular treatment or have an exposure, follow them forward over time, and then compare their outcomes with a similar group that has not been affected by the treatment or exposure being studied

A

Cohort Study: Prospective

74
Q

start with a cohort and go back in time to evaluate past exposures to risk factors

A

Cohort Study: Retrospective

75
Q

Strengths of __________ - May study multiple effects of a single exposure - Can identify a temporal relationship between exposure and disease (outcome) - Help confirm cause and effect of disease and the magnitude of the effect - Can measure incidence (rate) of disease - Calculate Relative Risk - Highest validity of observational study design

A

Cohort studies

76
Q

Limitations of __________ - Expensive and time consuming - Inefficient for studying rare diseases: Case-control more appropriate for rare diseases - Lose participants to follow-up - Risk of confounding variables - Retrospective studies require presence of records or recall

A

Cohort studies

77
Q

Cohort or Case-Control Summary? Start with exposure, look for disease Prospective or retrospective Common diseases High risk for drop out $$$

A

Cohort Study Summary

78
Q

Cohort or Case-Control Summary? Start with disease, look for exposure Retrospective Rare disease Recall and selection bias $

A

Case-Control Study Summary

79
Q
  • prevent any potential biases on the part of the investigators from the influencing the assignment of participants into different treatment groups. - generates random assignments - subject has an equal chance of being assigned to each group (control or intervention) - strives for comparability of the different treatment groups; however, its not guaranteed.
A

Randomized control studies

80
Q

Randomized __________ implies: - Specified hypotheses - Primary and secondary endpoints to address hypotheses - Methods for enrollment and follow up - Eligibility/Exclusionary criteria - Rigorous monitoring - Analysis plans and stopping rules

A

Randomized control studies Controlled

81
Q
  • Criteria for determining selection - Ensure that participants actually have the disease of interest. - Carefully select sample based on a reference population
A

Enrollment

82
Q

Stratifying our study population by each variable that we consider important, and then randomize participants to treatment groups within each stratum.

A

Allocation: How is randomization accomplished:

83
Q

How is randomization accomplished?

A
  • Computer programs - Envelope System
84
Q

The treatment assignment that is designated by a Random number is written on a card, and this card is placed inside an envelope. Each envelope is labeled on the outside: Patient 1, Patient 2, Patient 3…..etc. When the first patient is enrolled and consented the investigator opens the envelope and the treatment assignment is determined

A

Envelope System

85
Q

Comparable measurements in all study groups - Improvement - Side Effects or Adverse Reaction

A

Outcome

86
Q
  • concealment of group allocation from one or more individuals involved in a clinical research study. - compare two or more types of interventions.
A

Randomized control studies: Blinding

87
Q

After being observed for a certain period of time on one therapy; any changes are measured; patients are switched to the other therapy. - Must have a washout period!

A

Crossover: Planned

88
Q
  • Occurs when subjects who are randomized cross-over to the other group. - Lost the benefits of randomization. - Current practice to perform the analysis by intention to treat-according to the original randomized assignment
A

Crossover: Unplanned

89
Q

Blinding Type: Single, Double, Triple? - Allocation is concealed from only one group - Researchers OR Subjects

A

Single Blinding

90
Q

Blinding Type: Single, Double, Triple? - Allocation is concealed from both groups - Researchers AND subjects)

A

Double Blinding

91
Q

Blinding Type: Single, Double, Triple? Allocation is unknown to the subjects, the individuals who administer the treatment or intervention, and the individuals who assess the outcomes.

A

Triple Blinding

92
Q

Subjects may agree to be randomized, but following randomization they may not comply with the assignment treatment

A

Noncompliance

93
Q

study results will be to reduce any observed Differences, because the treatment group will include some who did not receive the therapy, and the no-treatment group may include some who received the treatme

A

Net Effect of non-compliance

94
Q

What is the Gold-Standard

A

Double-blinded Randomized Control Trial

95
Q

Limitations of __________

  • Large trials (may affect statistical power)
  • Long term follow-up (possible losses)
  • Compliance - Expensive
  • Possible ethical questions
  • Primum Non Nocere / ‘First Do No Harm’
A

Randomized control studies

96
Q

Strengths of __________ - Minimizes the chance for bias if randomization and blinding are done correctly

A

Randomized control studies

97
Q

Attempted to learn if the drug, surgical procedure, or administrative program works under ideal circumstance

A

Efficacy Trial

98
Q

Within the confines of the study, results appear to be accurate and the interpretation of the investigators I supported

A

Internal Validity

99
Q

Ability to apply results obtained from a study population to a broader population

A

External Validity/ Genealizibiity

100
Q

Quasi-experiments, know as __________ study?

A

Non-randomized control studies

101
Q

The control group is predetermined (without random assignment) and compared to a control group. - Volunteer to join the study OR - Are geographically close to the study site OR - Conveniently turn up (at a clinic, school) while the study is being conducted - Like the studies recruiting with fliers posted in the restroom

A

Non-randomized control studies

102
Q

Non-randomized control studies vs. RCS - inexpensive - not feasible to randomize all evaluation - Ethical problems may be perceived to occur in health services evaluation studies - By the time RCS are completed and data analyzed results may not be relevant anymore

A

Non-randomized control studies

103
Q

Limitations of __________ - Study group characteristics may not be balanced at baseline - Baseline differences between groups may confound the study’s results - Typical confounding variables include age, educational level, motivation, severity of illness, socio-economic status, income, comorbidities…etc

A

Non-randomized control studies

104
Q

Four major areas of __________ concern? Enrollment Allocation Follow Up Analysis

A

Ramdomized & Non-randomized Control Studies Methodological concern

105
Q

How was the study population chosen? - Inclusion vs. Exclusion - Representation - Controls similar to case subject

A

Ramdomized & Non-randomized Control Studies Methodological concern - Enrollment

106
Q

How were the subjects assigned to their study group? - Randomization and binding conducted - Consecutive or convenience

A

Ramdomized & Non-randomized Control Studies Methodological concern - Allocation

107
Q

How long are patients followed for? Adherence: - How well did the study subjects adhere to the treatment protocol? - Was the intervention too difficult to continue to participate? Attrition - How many subjects were lost to follow-up? - Why were they lost? Did they quit or die?

A

Ramdomized & Non-randomized Control Studies Methodological concern - Follow Up

108
Q

How was the data collected analyzed? - Are the effects of the intervention clearly defined? - Is there a clearly defined end point? - Did they provide an “intent to treat” analysis? - To what did they compare their data?

A

Ramdomized & Non-randomized Control Studies Methodological concern - Analysis

109
Q
  • Designs that summarize the work of other studies - Takes the results of a large numbers of primary research studies and combines them into one - Synthesis a great deal of research!
A

Systematic Reviews and Meta-analyses

110
Q
  • Thorough, comprehensive, and explicit way of interpreting the medical literature. - Appraise and synthesize all the empirical evidence to answer a given research question!
A

Systematic Reviews

111
Q
  • Statistical approach to combine the data derived from several selected studies - A method for combining data from several selected studies that are similar enough to develop a single conclusion that has greater statistical power - The conclusion is statistically stronger than any single study
A

Meta-analyses

112
Q

What is CPG?

A

Clinical Practice Guidlines

113
Q

Methodology of __________ Review 1. State objectives and outline eligibility criteria 2. Search for trials that meet criteria 3. Establish methods for assessing methodological quality of each study 4. Apply eligibility criteria and justify exclusions 5. Assemble the most complete collection possible 6. Analyze results using synthesis of data 7. Compare alternate analyses, if necessary 8. Prepare a critical summary of the review 9. Restate aims, methods, and results

A

Systematic Review Methodology

114
Q

Strengths of __________ Review

  • Exhaustive review
  • Less costly

Less time required than conducting a new study

  • Results can be generalized and extrapolated more broadly than individual studies
  • More reliable and accurate than individual studies
  • Considered an evidence-based resource
A

Systematic Review

115
Q

Limitations of __________ Review - Very time and labor consuming - May not be easy to combine studies

A

Systematic Review

116
Q

Strengths of __________ Review - Greater statistical power - Confirmatory data analysis - Greater ability to extrapolate to the general population

A

Meta-analyses Review

117
Q

the “average” – sum of the set divided by the number in the set

A

Measures of Central Tendency Mean

118
Q

The middle point (arrange the data smallest to largest, then find the middle point) The point/score at which 50% of scores fall below it and 50% fall above it

A

Measures of Central Tendency Median

119
Q

The score that occurs most frequently in a set of data

May have two most common values = “bimodal distribution”

Most frequently occurring value

This is the most general and least precise measure of central tendency

A

Measures of Central Tendency Mode

120
Q

Quantifies the amount of variability, or spread, around the mean of the measurements.

A

Standard Deviation vs. Variance (σ2 ) Variance (σ2 )

121
Q

A measure of variation of scores about the mean. The “average distance” to the mean Used more frequently than the variance Has the same units as the measurements of the mean. When comparing two groups, the group with the larger standard deviation exhibits a greater amount of variability (heterogeneous) while the groups with smaller deviation has less variability (homogeneous).

A

Standard Deviation vs. Variance (σ2 ) Standard Deviation

122
Q

Take each difference from the mean, square it, and then average the result.

A

Calculate Variance

123
Q
  • take the √ of the variance - “Bell Curve”
A

Calculate Standard Deviation

124
Q

Empirical rule for data used in __________?

A

Standard Deviation Bell Shaped Curve Analysis

125
Q

__________ Rule 68-95-99 - only applies to a set of data having a distribution that is approximately bell-shaped

A

Standard Deviation Empirical rule for data

126
Q

__________ Rule 68-95-99 - only applies to a set of data having a distribution that is approximately bell-shaped

A

Standard Deviation Empirical rule for data

127
Q

68-95-99

Approximately 68% of all scores fall with 1 standard deviation of the mean

Approximately 95% of all scores fall with 2 standard deviations of the mean

Approximately 99.7% of all scores fall with 3 standard deviations of the mean

A

Empirical rule for data

128
Q

Evaluates the strength of linear relationships or associations between variables

Looks at correlation: How strongly is one variable related to another?

A

Scatterplot

129
Q

Direct or inverse relationship?

  • X increases and Y increases = positive correlation
  • X increases and Y decreases = negative correlation
  • 0 is no correlation
A

Scatterplot

Correlation

130
Q

The absolute value of the coefficient (its size, not its sign) tells you how strong the relationship is between the variables.

A

Correlation Coefficient

“r ” (rho)

131
Q

Tells us how strongly two variables are related

◦“r” can not be > 1 or < -1

◦Closer to -1 or +1: the stronger the relationship

◦Closer to 0 : the weaker the relationship

A

Correlation Coeffiient Relationtionship

132
Q

The most common measure of association. Results can be misleading if the relationship is non-linear

Pearson’s correlation is very sensitive to outlying values

A

Pearson Correlation

133
Q

A non-parametric version of Pearson’s correlation. The calculation is based on the ranks of the data points of the x and y values

A

Spearman Correlation

134
Q

The statement that establishes a relationship between variables being assessed

  • Example: In a clinical trial the hypothesis states the new drug is better the placebo

“research hypothesis”

Stating the expected relationship between independent and dependent variables.

If there IS a statistically significant difference, then the researchers “ACCEPT” the alternative hypothesis and “REJECT” the null hypothesis.

A

Alternative hypothesis (Ha or H1)

135
Q

The statement of no difference or no relationship between the variables

  • Example: In a clinical drug trial the null hypothesis states that the new drug is no better than placebo

If there IS a statistically significant difference, then the researchers must “REJECT” the Null hypothesis

If there IS NOT a statically significant difference, then the researchers must “RETAIN” or “FAIL to REJECT” the Null hypothesis.

A

Null hypothesis (Ho)

136
Q

Rejection error or an α error.

◦Made if we reject the null hypothesis when null hypothesis is true.

◦The probability of make a type I error is determined by the significance level of the test.

A

Hypothesis Error

Type I error

137
Q
A

Hypothesis Error

138
Q

An acceptance error or an β error

◦made if we fail to reject null hypothesis.

◦The probability of committing a type II error is represented by the Greek letter β.

A

Hypothesis Error

Type 2 error

139
Q

◦The probability of finding an effect

◦The probability of correctly rejecting the null hypothesis

◦The probability of seeing a true effect if one exists

◦Designers of studies typically aim for a power of 80% or 0.8

◦Implies there is an 80% chance of getting it right

◦Generally speaking: More people = more power

A

Power Analysis

Statistical Power

140
Q

__________ may also be thought of as the likelihood that a particular study will detect a deviation from the null hypothesis given that one exists.

__________ is the probability of avoiding a type II error.

A

Power

141
Q

1- β

Called the __________ of the test of hypothesis.

A

Power

142
Q

Calculates the number of participants a study must have to draw accurate conclusions

◦Takes into consideration: estimated effect size, sample means, etc.

A

Power Analysis

143
Q

The probability of rejecting a true H0 (Null Hyp)

α = .05 usually set, acceptable error

Chance that 5 times out of 100 the H0 (Null Hyp) would be falsely rejected

A

Significance

144
Q

reject the H0

the results are statistically significant

A

Statistical significance and p-value

p ≤ α

145
Q

Chance of random error

A

P-Value

P

146
Q

fail reject the H0

the results not statistically significant

A

Statistical significance and P-Value

p > α

147
Q
  • Less than 5% chance the effect happened by chance.
  • “There is less than a 5% chance that the null hypothesis is falsely rejected”
  • Often reported as “significant at the 0.05 level.”
A

Statistical significance and p-value

A statistically significant p = or < .05

148
Q
  • If the number of subjects is small, p value tells us that the effect was either large or consistent (or both)
  • If the number of subjects is large, the effect size may not be that large
A

Statistical significance and p-value

A highly significant p < .001

149
Q
  • If the number of subjects is small, there might not have been enough subjects to find a difference that truly does exist
  • If the number of subjects is large, we can be confident that either there is no difference between treatments, or the treatment effect is not consistent
A

Statistical significance and p-value

An insignificant p > .05

150
Q
  • How large the effect was
  • How consistent the effect was
  • How many patients were studied
A

Statistical significance and p-value

Factors to consider

151
Q

◦More important than p value – a better determination of significance

◦Any statistic is simply an estimate of the true value of that statistic

◦CI produces a range within which the true value most likely lies

◦95% CI states that we can be 95% certain that the “true” value is within the CI range

◦Narrower CI is better

◦If the CI include 1 (null value) then the results is clinical insignificant.

A

Confidence interval (CI)

152
Q

A screening test is used to separate from a large group of apparently well persons those who have a high probability of having the disease, so that they may be given a diagnostic work up, and if diseased can be treated.

A

Screening Tests

153
Q
  • The target disease is an important cause of mortality and morbidity.
  • A proven and acceptable test exists to detect individuals at an early stage of disease.
  • There is a treatment available to prevent mortality and morbidity once positives have been identified
A

Screen Conditions

154
Q

The proportion of people with the disease who have a positive test for the disease.

  • The ability of the test to identify correctly those who have the test.
A

Sensitivity

155
Q

The proportion of people without the disease who have a negative test.

  • The ability of the test to identify correctly those who do not have the disease
A

Specificity

156
Q
  • test’s ability to identify presence of disease
  • test with high sensitivity will not miss many patients who have the disease
  • A highly useful test when NEGATIVE
  • Tends to rule OUT the disease
  • High Sensitivity means low probability of false negative
A

Sensitivity Screening

157
Q
  • Screening test’s ability to truly identify absence of disease
  • That is, how likely is a negative test actually reporting the right answer?
  • A highly useful test when it is POSITIVE
  • Tends to rule IN the disease
  • High Specificity means low probability of false positive
A

Specificity Screening

158
Q

Usefulness of Sensitivity & Specificity?

A
  • A highly sensitive test is most useful to the clinician when it is NEGATIVE
  • A highly specific test is most useful to the clinician when it is POSITIVE
159
Q

proportion of patients who HAVE the disease and a positive test

A

Positive Predictive Value (PPV)

160
Q

Proportion of patients who DO NOT HAVE the disease, and have a negative test

A

Negative Predictive Value (NPV)

161
Q

Percent of patients with positive test who actually have the disease

  • Assesses reliability of positive test
  • i.e. PPV 90% = positive test 90% of the time the test is correct

With low prevalence (% of population) of disease:

  • Lower PPV
  • False positives increase
  • Less reliable positive test result
A

Positive predictive value (PPV)

162
Q

Percentage of patients with a negative test who actually do NOT have the disease

  • Assesses reliability of a negative test
  • i.e. NPV 90% = negative 90% of the time the test is correct

With low prevalence(% of pop) of disease :

  • Higher NPV
  • False negative test decreased
  • A negative test result is more reliable
A

Negative Predictive Value (NPV)

163
Q

The occurrence, rate, or frequency of a disease

  • Obtained from cohort studies
  • Must follow a cohort through time
A

Incidence

164
Q

The number of occurrences at one particular time

  • Obtained from cross-sectional studies
  • No time line, only a snap shot
A

Prevalence

165
Q
  • explore the relationship between two continuous variables
  • method of predicting change in the dependent variable by changing one or more independent variables
  • What % of variation in the dependent variable can be explained by a change in the independent variable
A

Regression analysis

166
Q

Four __________ types:

Categorical

  • Nominal
  • Ordinal

Continuous

  • Interval
  • Ratio
A

Data Type

167
Q

Named categories with no implied order

  • ◦Gender, race, ABO blood type, group
A

Categorical Data

Nominal

168
Q

Sequenced or ranked data

  • Smallest to largest, lightest to heaviest, easiest to most difficult
A

Categorical Data

Ordinal

169
Q

Intervals along the scale are equal to one another (i.e. integers)

  • Set on an underlying continuum that allows you to talk about how much higher one value is than another
  • 0 on the scale does not mean the absence of the item (e.g., degrees Fahrenheit)
A

Continuous Data

Interval

170
Q

Characterized by the presence of absolute zero on the scale

  • An absence of any of the trait being measured (e.g. weight)
  • Most precise
A

Continuous Data

Ratio

171
Q

__________ Method

  1. Sequential (Two Stage) Testing
  2. Simultaneous Testing
A

Testing Method

172
Q
  • Screening, a less expensive, less invasive, or less uncomfortable test is generally performed first
    • Those that screen positive are recalled for further testing with a more expensive, more invasive, or more uncomfortable test.
  • Loss in net sensitivity, and gain in net specificity
A

Multiple Test Method

Sequential (Two-stage) Testing

173
Q
  • Net gain in sensitivity, and net loss in specificity.
  • Patient is considered positive if they test positive on any test or both.
  • Patient is considered negative if they test negative on all the tests performed.
A

Multiple Test Method

Simultaneous Testing

IPAP Research & Evaluation (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions