Research And Eval Flashcards
What is the gold standard of research
RCT
What is the definition of Evidence Based Practice
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
*Results in the best possible outcome for your patients**
What is a meta-analysis
Pools data and statistically interprets is from several studies
What is an efficacy trial
Attempts to learn if a drug, surgical procedure, or admin program works under ideal circumstances
What is the Pearson correlation
The most common measure of correlation
What is subject variation in measurement error
Variability of individual subjects
Like different answers on a survey
What is non differential miscalculation
When the bias is random or equally present in each group ( case vs control )
Does a chi square give any indication about the variable relationship strength
NO
What is a histogram,
Is a bar graph, comprised of a series of columns, each representing one score or class interval
What does a negative LR tell you
LR-
Is the proportion of diseased people with a negative test (1-sensitivity) divided by the proportion of non-diseased people with a negative test (specificity)
What kind of study is a BP Study
A normative study
What is evidence based medicine
To integrate clinical expertise with the best available evidence
What are three types of experimental research designs
RCTs, (gold standard)
Single subject
Quasi-experiments
What is non-experimental research
Refers to investigation that are generally more descriptive or exploratory in nature and that exhibit direct control over the studied variables
What is misclassification bias
Occurs when those that have the disease are mistakenly put in the control group
A random error is also know as
Chance variation
What are the four paradigm shifts which have emerged in healthcare
- evidence based practice
- focus on translational research
- conceptualization of health and disability
- importance of Inter professional collaboration
What it retrospective research
Examination of date that has been collected in the past
What biases are Systematic and meta anylsis subject to
Inclusion/ exclusion criteria
What is an example of a quantitative question
On a scale of 1-10 how is your pain
What are two types of measurement errors
Systematic errors: are predictable errors of measurement
Random errors: are due to chance and can effect a subjects measurement in a unpredictable way
What is a systematic review
Is a thorough, comprehensive, structured way of combining findings from several sources with an analysis of the methodological quality of the studies.,
It is an interpretation of the available medical literature
What is observer variation in measurement error
Variability of measurements based on the fatigue of the observer, variations in training
What intrarater reliability
Refers to the stability of data recorder by one individual across two or more trials
Do Cohort study’s develop relative risk
YES and Odds ratios
What does analytic research do
Analyzes associations
Investigates Relationships
TESTS hypotheses
What does a logistical regression do
Estimates the probability of an outcome associated with a dichotomous response for a single or multiple variables
What kind of research observe natural phenomenon
Observational
What is translational research
refers to the application of basic scientific findings to clinically relevant issues, and simultaneously, the generation of scientific questions based on clinical dilemmas.
What is a case report
A narrative in the professional literal that IDs a single incident and discusses pertinent factors related to the pt.
What is observational research
Phenomena are observed rather than manipulated
What is a paradigm
A set of assumptions, concepts, or values that make a framework for reality
-defines what questions are important
What is the formula for relative risk
EER
_____
CER
What is the fishers exact test
A non-parametric test, can be used with small or sparsely distributed data sets
What are the five study types of PICO questions
Therapy Diagnosis Prevention Etiology Prognosis
What minimizes bias
Empirical-ism
What is systems based practice
To asses, coordinate, and improve the silvery and effectiveness of health care and patient outcomes
What are two types of validity
Internal validity: within the confines of the study appear to be accurate and the interpretation of the results is supported
External Validity: result and interpretations of the study apply outside the studied population. Also called generalizability
What is social desire ability bias
People want to be seen in a favorable social light so they give more positive answers
If relative risk is less than 1
Negative associated, possibly protective
What is peer review
The process by which an authors peers and recognized researchers in the filled read and evaluate a paper submitted for publication
What are the steps to the research process
ID the research question (Who, what, how) Design the study Implement the study Analyze the data Disseminate the findings Close the loop (Replication/ additional research)
What defines professionalism
On going profesional development
What increases the strength of a case control study
Adding multiple controls
What is information bias
Occurs when the means for obtaining information about subjects in the study are inadequate so that as a result some of the information regarding the exposure or outcomes are incorrect
What is recall bais
Is the main form of information bias in case control studies
When there is a differntional recall of exposure between cases and controls
What is the measurement of outcomes triad
- Structure: Assessed through organization standards
- Process: Quality assurance programs
- Outcomes: Morbidity, mortality, length of stay, and readmissions
What is qualitative research
Naturalist, humanistic or idealistic approach to research
Explore a social or human problem
What do cross sectional studies determine
Prevalence NOT incidence
What is clinical research
Structures process of investigation facts and theories and exploring connections
-utilizes a variety of quantitative and qualitative measurement tools
What part of a study tells you if the results are valid or meaningful
The methods section
What is an example of a qualitative question
Tell me about your pain ?
What reduces measurement errors
- Double blinding
- Independent observers
- Validating instruments
- Providing supervised training
- Using multiple observers and data sources
If Relative Risk is equal to 1
No association
What are descriptive statistics uses for
To characterize the shape, central tendency, and variability within a diet of data, often with the inten to describe a population
What is absolute risk reduction
The actual reduction in events in the treated group
Is the TRUE DIFFERENCE between the experiment and the control intervention
What is survivor bias
Can lead to erroneros associations between an exposure and outcome based on survivorship of the subject in a study
What are the strengths of a cross sectional study
Can asses multiple outcomes and exposures simultaneously
Lead to further studies
Can generate prevalence
Can calculate odds ratios
What are case control studies
Studies in which patients who already have a specific condition (cases)are compared with people who do not (controls)
What is the purpose of a case-control study
To determine if the frequency of an exposure or certain personal characteristics are different for those who did/ did not get the disease
What are two general types of errors
Unpredictable
And errors made in a biased, systematic way
how do researchers use statistics
To estimate population parameters
Clinicians must be able to use what two types of sources
Primary and Secondary
Define internal validity
Within the confines of the study ,
Results appear to be accurate interpretations of the investigations supported
What is a recall bias
The possible inaccuracy of recalling medical history or previous exposures
What does a positive LR tell you
(LR+)
is the reaction of the proportion of diseased people with a positive test result (sensitivity) to the proportion of non-diseased people with a positive result (1-specificity)
What is the scientific method
Defines as the systematic, empirical, and controlled critical examination fo hypothetical propositions about the associations of natural phenomena
What are two types of date
Categorical and continuous
What is the number needed to treat
Expresses the likelihood of the treatment to benefit an individual patient
What are confounding variables
Variable that correlates directly or indirectly with the dependent and independent variables
What does covariate mean
An extraneous variable that is statistically controlled in an analysis of covariance, so that the relationship between the independent and dependent variables is analysed with the effects of the extraneous factor removed
What is quantitative research
Measurement of outcomes using numerical date under standardized conditions
What are case series used for
Examine adveres events or effects
Catalog new diseases or outbreaks
Determine safety of a new treatment
Discuss potential efficacy of a new treatment
A LR+…..
A LR-…
LR+ rules in the disease
LR- rules out a disease
What are filtered resources
Evaluate how recently the summary or study was updated of revised
Examples: clinical practice guidelines
Cochran Database of systematic Reviews
What kind of research is a cross sectional study
Observational
What is the dependent variable
AKA the outcome variable
Response of effect that is presumed to vary depending on the independent variable.,
What was the purpose of the Impact factor/ score
Was to support budgetary decisions of libraries, not to serve as a measure of scientific worth of individual studies
What is categorical data
Nominal data- classifications
Ordinal Data- ranked or sequenced data
What is longitudinal research
Follows a cohort of subjects over time, repeated measurements at prescribed intervals
What are measurements
Defined as the process of assigning numeral to variables to represent quantities of characteristics according to certain rules
What is scientific research
The process of investigation facts and theories in a scientific way to examine relationships among clínical phenomena to generat evidence for decision making
What are the strengths of a meta analyses
Generate great statistical power
Confirmatory data analysis
And ability to extrapolate the general population
What is inferential statistics
Involve a decision making process allowing estimation of population characteristics from sample data
What type of square test would you use if the date was in paired samples
McNemar test for matched pairs
What is the Alternative hypothesis
H_a or H_1
The statement that establishes a relationship between variables being assessed
What does the chi-square for equality of proportion test
Computed the same way as the CI square test for independence, but instead tests the hypothesis that the distribution of some variable in the same in all populations
What is exploratory research
Cohort studies
Case Control Studies
-used to examine phenomena of interés and how it relates to other factors
What is outcomes research
Wusses of intervention in clinical practice
Encompasses outcomes: Morbidity, mortality, disease development, and disease readmissions
Is evidence alone enough to make a clinical decision
NO
What is the main form of information bias in case control studies
RECALL BIAS
What are limitations on systematic reviews
Very time and labor consuming
May not be easy to combine studies
What is the most general and least precise measure of central tendency
The Mode
What does relative risk measure
The magnitude of an association between an exposed and non exposed group
What does a Odds ration tell you
It measures the strength of association between an exposure and a diseases
What is relative risk
Basic risk statements express the likelihood that a particular event will occur within a population
IDs what in our environment can lead to beneficial or adverse medical outcomes
What are variables
Characteristics of interest that assume different values for different subjects
Like age, gender, disease status
Must be clearly defined
What is a regression analysis
A method of predicting change in the dependent variable by changing one or more independent variable
Y=mx+b
What is the range of a LR-
0.0 to 1.0, null value 1.0
The smaller the better
Desirable 0.2 or less
What is the highest form of evidence
Systematic Reviews Then Critically Appraised Topics ThenCritically Appraised Individual Articles Then RCT Then COHORTS Then Case Studies Lastly expert opinion
What do case reports and series inherently lack
Sufficient methodological vigor
-may be circumstantial evidence
What are the 5 types of Clinical questions
- therapy
- harm
- diff. Diagnosis
- diagnosis
- prognosis
What is the measurement error
The difference between the true value and the observed value
What does the chi square test of goodness of fit test?
In used to test the hypothesis that the distribution of a categorical variable within a population followed a specific patter of proportion
A RCT is what type of Resouce
Unfiltered
What is a sampling error
The tendency for sample values to differ from population values
What does “control” mean in the scientific method
Allows the researcher to understand how one phenomenon relates to another, controlling factors are not directly related to the variables in question.
What are the limitations of Meta Analyses
Difficult and time consuming to indemnity appropriate studies
Not all studies provide adequate data
Requires advanced techniques
Heterogeneity
Subject to many biases
What are the limitations of case- control studies
Only produce a single outcome High risk for bias High risk for confounding variables CANT determine prevalence CANT determine incidence CANT calculate relative risk
What does the chi square of independence test
Tests the null hypothesis that the variables are independent of eachother, that there is no relationship between two variables
What is a funding bias
Characterizing as association owing to the absence or withdrawal of financial or other types of support
People are more motivated if you pay them
What is a relative risk reduction
The percentage difference in outcome between control and experimental groups
**makes insignificant findings seems significant **
What is qualitative research
More concerned with a deep understanding of a phenomenon through narrative description
A hospital guideline is what type of resource
Filtered
What is Postive predictive value
Estimates the likelihood that a pt who tests positive actually has the disease
What is a likelihood ration
Summarizes the same type of info a sensitivity and specificity, but can be used to calculate the probability of disease in a LOW PREVALENCE SETTING
-provides a indication of the tests discriminatory power
What is selection bias
Inappropriate selection of study participants that may lead to an erroneous association between an exposure and and outcome
What is the difference of cross sectional vs longitudinal studies
Cross sectional looks at a specific point in time.
Longitudinal you repeatedly collect information from the same sample over an extended period of time
What is a non-inferiority trial
Done to show that the new treatment is an s good or better than the standard
What is frequency distribution
A table of ranch ordered scores that show the number of times each value occurs
Which type of error ( I or II) is worse
Type I is generally a worse error than type II
What are the four components of a clinical question
P.I.C.O.
Phase II trials
Explores efficacy by measuring relevant outcomes
What are the four main areas of methodological concern for RCTs
Enrollment- how was the population chosen
Allocation- Randomized and how’?
Follow up- length of patient following
ANALYSIS- how was data collected
Mesures of population characteristics are called…
Parameters
What is the manifest level
Basic level
A descriptive account of the date
What is a publication bias
Tendency of researcher and editors to treat postive results from negative or inconclusive results, often with a preference of positive findings
What is the first step to minimize error
The power analysis is the first step in reducing errors
What is Hawthorne effect
People act different when they know they are being watched
What is surveillance bias
Occurs when outcome ascertainment is better in a monitored population than in the general population
What is “Validity of Data”
Degree to which a measurement represents a true value
What is the “noise” that gets in the way of finding the true value
Measurement error
What are phase III trial s
Compared the new treatment with standard care ,
Large group of PTs
What are the PA Competencies
Patient Care
Professionalism
Systems- Based Practice
What are types of systematic error
Predictable errors or errors made by biases
Investigator or Interviewer Biases
Subject Biases
- Social Desirability: subjects respond with what they think is the right answer
- Hawthorne Effect : people may act different when they know they are being watched.
What does it mean to be “systematic”
To have a sequence that starts with the identification of a problem, then follows an organized collection and analysis of data and leads to interpretation of the findings
What are unfiltered sources
AKA primary sources
It’s up to the reader to determine quality and validity of the source
What is prospective research
Variables are measured through direct recording in the present tense
What kind of research is active intervention
Experimental
What is a superiority trail
Compared one treatment to another directly
What does “reliability” mean
Degree to which the measurements are reproducible
What is continuous data
Interval data: intervals along the scale are equal to one another
Ratios: characterized by the presence of absolute zero on the scale
(no negative values)
What are Boolean logic primary operators
Combining search terms with and, not, or
What is the simplest measure of variability
The range
What is a confounding variable
An extraneous variable that is related to the independent and dependent variable, but not the casual pathway.
What is basic research
Done in a lab to obtain empirical data
Used to develop, refine, or test a theory
What is the latent level
Higher level
A more interpretative analysis that is concerned with the response as well as what may have been inferred or implied
What are the limitations of cross sectional studies
No time reference
Only useful for common conditions
CANNOT calculate incidence
Can case-control studies determine relative risk
NO, they can make odds ratio that can be a close indicator of relative risk
What are the strengths of Cohort studies
Can identify temporal relationships between exposure and disease
Can help confirm cause and effect and magnitude of effect
Can measure incidence
Can calcule relative rise
What is the 68-95-99 rule
The standard deviation
That 68% of all scores fall within 1 stand. Div of the mean
And 95 % of all scores fall within 2
Stan. Div of the mean
And 99.7% of all scores fall within 3 standard divs of the mean
What is the most coming confounding fact
The selection factor
- Theory based
- Stats based
What does descriptive research emcompass
Observes associations
Shows patterns
Generates hypotheses
Provides clues to disease etiology
What does an Odds ration greater than 1 indicate
Less than 1 indicate
> 1: increased occurrence
<1 decrease occurrence
(protective measure)
What is applied research
Directed toward solving immediate practical problems with functional application
What is a scoping review
A broad less structured approach that offers assessment of emerging evidence
What are background resources
Used to learn about a new topic or refresh knowledge
Usually in textbooks, medscape, up to date
What is the control bias “matching “
Selection of controls so they are similar to the cases.
What is the range of a LR+
1.0 to infinity, null value 1.0
The bigger the better
Greater than 5 is most desirable
What is a cohort
A group of people who share a common characteristic or experience and all remain in the group for a period of time
What is the strongest observational design
COHORT STUDY
What is a Type I error
Finding an effect that isn’t real
Rejecting the Null hypothesis when the association isn’t real
Like convicting an innocent man
What is a intention to treat analysis
Data is analyzed according to original random assignment, regardless of the treatment subjects actually receive
Helps reduce bias if there are dropouts in the study
What is the hierarchy of data
Ratio- best
Interval
Ordinal
Nominal- worst
What are the limitations of cohort studies
Expensive and time consuming Inefficient for rare diseases Lose participants to follow ups Confounding variables Recall biases
how is a quasistudy different from a RCT
In non randomized
What is descriptive research
Attempts to describe a group of individuals on a set of variables to document their characteristics
- patterns of growth
- Change over time
- Normative studies
What are the strengths of Systematic Reviews
Exhaustive
Less costly than a new study
Less time required than conduction a study
Results can be generalized
More reliable and accurate than studies on their own
Considered Evidence Bases medicine
What are the limitations of a Non-randomized control study
Characteristics are not balanced at baseline
May have confounding variables
What are three types of variables
Independent
Dependent
And confounding variables
If the exposure is related to disease then the OR will be
Greater than 1
What two things are used to generate practice guidelines
Systematic review and meta-analyses
What is the “n”
Distribution
The total number of scores in the distribution is give the symbol “n”
NNT for very effective treatments are usually in the range of …
2-4
What’s are the potential biases in Cohort studies
Selection Bias
Information Bias
Observer Bias
What is a equivalence trial
Done to show the new drug in no more or less effective that the standard
What is instrument variation in measurement errors
That not all instruments are perfectly accurate
Like different BP cuffs
What is a lost to follow up bias
Occurs when subject leaves a study different based on exposure bias
What is epidemiology
The study of distribution and determinants of health related states or events in specific populations, and the application of the study to control health problems
What is an epidemiological bias
An incorrect assessment of the association between exposure and an effect in the target population
Anything which erroneously influences conclusions about a study group
What is the independent variable
The variable that is presumed to cause a dependent variable,
The variable that is manipulated or controlled by the researcher
Describe the multi step process of epidemiology
- Determine an association between exposure and outcome
- Is the association causal ?
- Derive appropriate inferences about a possible causal relationship from patterns found
What are the strengths of Case- Control Studies
Good for studying rare outcomes
Simple and Fast
Inexpensive
Can Calculate odd rations
What three things combine to make evidence based practice
Best available research
Patient values and preferences
Clinical expertise
LR=
Like hood of a particulare result in someone WITH the disease
_____________________________
Like hood of the same result in someone WITHOUT the disease
What is a control event rate (CER) %
A measure of how often a particular even occurs within the scientific control group of an experiment
What does it mean to be empirical
To document objective data through direct observation
Odds ratios in case control studies are a good approximation of RR when…
The cases studies are representative of all people with the disease
When the controls are representative of all people with the disease
When the disease is common
If relative risk is greater than 1
Positive association, possibly casual
What are phase IV trails
Post marketing
Looks at long term use
In a blinded study what mayst planned crossover have…
A washout period
What are the objectives of Epidemiology
To reduce morbidity and mortality
To determine the extent of disease in communities
The study the natural history of prognosis of a disease
Provide a foundation for developing policy related to environmental problems
What are some examples of descriptive studies
Care reports and Case Studies
What is secondary literature
Databases and Point of Care resources
What is outcome management
Interdisciplinary process aimed at determining best practices
A descriptive index computed from the sample data is called a…
Statistic
What are the progression of steps in clinical trials
Preclinical phase (Basic research done in labs with animals)
Phase I, II, III, then IV trials
Define external validity
Ability to apply results obtained from a study population to a broader population
Aka generalizability
What is an effectiveness trial
Attempts to learn if the drug, procedure works under real world circumstances
What is the dependent variable
A response variable that is assumed to depend on or be caused by another (independent) variable.
What is primary literature
Original study
If the exposure is protecting of the disease then the OR will be
Less than 1
What are the strengths of RCT
Randomization High internal validity Can make inferences Can estimate risk directly **GOLD STANDARD**
What is experimental research
Researcher manipulates and controls one or more variables and observes the resultant variation of other variables
What are the limitations of RCT
Low external validity Expensive Time consuming Resource intensive Long term follow ups Compliance Possible ethical questions
What are phase I trails
Looks at treatment safety in small groups
In unplanned crossover of blinded study … what is the cause, and beat does it lean towards?
Intention to treat
Leans toward the null
What is the Chi-square test
One of the most common ways to compare two or more variables
What do scatter-plots do
Evaluate the strength of linear relationship or associations between variables
What is negative predictive power
Estimates the probability that a person who tests negative is actually disease free
If the exposure does not effect the disease then the OR will be
~1
What is practice-based learning and improvement
A systematic methodology
Locate, appraise, and integrate evidence from scientific studies
Apply knowledge from study designs and statistical methods, and to address personal biases
What is probability
The likely hood that any one event will occur, given all the possible outcomes, shown as p.
What is an independent variable
Something that will predict or cause the outcome
The intervention, the treatment, and the age, gender, martial status ect.
What is the simplified process of Evidence Based practice
Asses (identify need to gather info) Ask (PICOTT) Acquire Appraise Apply
What does a T-Test compute
A P value to test the null hypothesis
What is the “distribution”
The total set of score for a particular variable
WHAT INFLUENCES PATIENT CA
Current Scientific Literature
What is the Experimental Event Rate (EER) %
A measure of how often a particular event occurs within the expire to al group of a experiment
What is a type II error
Missing an effect that does exist
Retaining or failing to reject the null hypothesis when the association is real
Not convicting a guilty man
What is the null hypothesis
H_0
The statement of no difference or no relationship between the variables
What is a cohort study
An epidemiological investigation that follows groups with common characteristics over a specified period of time
