EBM Midterm: Old Quiz Questions plus 2021 Quizzes

Control group risk

# of control people who died/# number of total people in control group

Experimental group risk

# of people in experimental group who died/# total people in experimental group

A 78-year-old Caucasian man presents to a rural outpatient clinic to be evaluated for unintentional weight loss of 5% over the past 6 months. He reports decreased appetite but denies abdominal pain or weight loss. Other than being thin, his physical exam is normal. He takes Lisinopril for hypertension. When looking at research articles on the diagnoses associated with unintentional weight loss, which of the following study populations would be the most appropriate match for the above patient?

1301 patients referred consecutively from a rural primary care clinic

Which of the following statements about likelihood ratios (LR) is correct?

A LR 2.0 increases the probability that the target disorder is present

The main difference between a systematic review and a meta-analysis is which of the following?

A meta-analysis contains statistical pooling from different studies

None of the care providers, investigators, or participants know if the next eligible participant will receive the treatment or the control

Allocation Concealment

In the world of evidence-based medicine, PICO is:

An acronym to help clinicians create clinical questions

A 68-year-old female patient presents to your clinic with symptoms of mild depression that have lasted for two months. Her daughter would like her to get on antidepressants, but the patient would like to try an alternative before starting medication. She has read about mindfulness meditation and wonders if it could be an effective treatment in reducing or eliminating her depression. Using the PICO(T) format, what is the comparison/comparator in this example?

Antidepressants (what we are comparing the intervention to)

What is AUC

Area Under the Curve; A measurement of the overall quality of the diagnostic test

Descriptions of a series of patients

Case Series

The study design relies on the initial identification of patients with the outcome of interest and the selection of individuals who do not have the outcome of interest.

Case-Control Study

Overcomes temporal delays and the need for huge sample sizes to accumulate rare events

Case-control

Feasible when randomization of exposure not possible, generalizability

Cohort

Investigators identify exposed and non-exposed groups of patients and follow them forward in time.

Cohort Study

When is ANOVA (analysis of variance) used?

Comparing multiple groups

Systematic differences between research groups

Confounding

The degree of association among different variables or phenomena

Correlation

All participants receive both the experimental and the control intervention in a sequence

Cross Over

The study design is based on an assembled population of exposed and non-exposed participants, AND the outcome is measured at the same point in time.

Cross Sectional Study

Which of the following statements best describes in what way clinicians generally help patients?

Dx, Tx, Prognosis

Uncertainty about the utility of an intervention

Equipoise

How is relative risk calculated?

Experimental group risk/Control group risk

Pretest probabilities that come from clinician intuition have very little risk of bias. T/F

False

True/False. Surrogate Outcomes are measures that are important to patients, such as a lab value like Hemoglobin A1C.

False

True/False: Regression analyses give you means and standard deviations

False

Research has shown that it's best to stick with your gut instinct when selecting answers during a test. T/F

False! Use the power of rethinking.

True or False: Making the mistake of concluding that treatment and control differ when they actually do not is a Type II error.

False, it is a type I error

Airport security scanners that go off for both true positives (weapons) and false positives (jewelry) are demonstrating:

High sensitivity; they think it's best to get some false positives to be sure that they catch all potential true positives

According to the Understanding Medical Tests article, diagnostic tests which are studied in a population where the disease is highly prevalent can lead to:

Inflated positive predictive value

Which of the following statements is the best regarding Bias?

It deals with the systematic differences from the truth

What is the absolute risk reduction (or risk difference) and how do you calculate it?

It is the difference between the risk of death in the control group and the risk of death in the experimental group (EGR), calculated by: Control group risk - Experimental group risk

If p<α but R=0.99, is there a significant relationship between two variables?

No, because in order to have a significant relationship p>α, even if R is close to 1

If you're looking for research articles on the impact prenatal opiate use has on children after they are born, what type of study would provide you with the highest level of available evidence?

Observational Studies (Case-Control or Cohort)

A sound method for formulating a research question

PICO

When looking at therapy or harm,which of the following best defines the acronym PICO?

Patients, intervention, comparison, outcome

A statistical tool denoted by r, can range from -1.0 to 1.0

Pearson Correlation Coefficient

The _________ is the most rigorous and robust research method for determining whether a cause-effect relationship exists between an intervention and an outcome.

RCT

Low susceptibility to bias

Randomized Clinical Trial

Using the relationship among different variables to predict or make a causal inference

Regression

Diagnostic research studies that use an unrepresentative patient selection process are said to have what kind of bias?

Spectrum bias

Which of the following types of figures is the most informative way to depict the results of a prognosis study?

Survival curve

What is a post-hoc analysis?

Tells you what the p-values are for each group being analyzed and whether the differences are significant

Negative predictive value

The proportion of people with a negative test that don't have the disease.

Positive predictive value

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

Which of the following best exemplifies a way to recognize unrepresentative samples in Prognosis studies?

The sample is drawn from a tertiary care center, and your patient is from community based clinic

Which of the following factors would lower a clinicians decision threshold for testing?

The target disorder is deadly if undiagnosed

Which of the following best describes the use of non-parametric tests?

They are to be used with data that is not normally distributed

In the podcast, 'The Easiest Person to Fool' Adam Grant describes the idea of people confusing a challenge to their ideas as a threat to their ego as

Totalitarian ego

True or False: Blinding is a process that conceals whether patients are receiving the experimental therapy or control therapy.

True

True or False: Evidence Based Medicine (EBM) places the observations of individual clinicians at the lowest level of hierarchy?

True

True or False: For each type of question, EBM suggests a hierarchy of research designs to minimize the risk of bias.

True

True or False: It may be considered unethical to use a Randomized Control Trial (RCT) study design to determine the harmful effects of a treatment on patients.

True

True/False. Patient important outcomes are measures important to patients, such as a decreased risk of blindness from micro-vascular damage.

True

True/False: One thing that the NNT does, is assists the clinicians in helping patients weigh the benefits and downsides associated with treatment options

True

Textbooks are a good source to answer background questions. T/F

True. Provide general information.

Task conflict is the idea that people/teams can debate and argue about issues but not take it personally. T/F

True; the opposite is relationship conflict

How is relative risk reduction calculated?

[1 - (EGR/CGR)] x 100%

Which of the following generally represents a large effect size? a. 0.8 SD b. 0.5 SD c. 0.2 SD

a. 0.8 SD

As relevant to physician assistants, searching for evidence is best described which of the following? a. A basic clinical skill b. What librarians do c. What police investigators do

a. A basic clinical skill

What is the Grade approach in in research or research appraisal? a. A system to rate the quality of evidence b. A series of microarray experiments c. A method of enrolling patients d. An approach to improve the appropriateness of health care services research

a. A system to rate the quality of evidence

Which of the following is an example of a Federated search resource? a. ACCESSSS b. DynaMed c. MEDLINE d. ACP Journal Club

a. ACCESSSS

Which of the following best describes Foreground Questions? a. Are higher level question than background questions b. Are typically what novice clinicians ask c. Are lower level questions than background questions d. Are typically what expert clinicians ask about a new disease

a. Are higher level question than background questions

Descriptions of a series of patients a. Case series b. Case reports c. Cohort study d. Case-control study e. Cross sectional study

a. Case series

Which of the following is the most popular approach to dealing with chance agreement? a. Chance-corrected agreement b. ANOVA c. Chi Square d. Heterogeneity

a. Chance-corrected agreement

Which of the following are the best description of the three fundamental principles of Evidence based medicine (EBM)? a. Decisions must weigh the risks and benefits b. Clinicians must be aware of the best available evidence c. EBM provides guidance to trustworthiness d. Extensive knowledge of statistics is essential

a. Decisions must weigh the risks and benefits b. Clinicians must be aware of the best available evidence c. EBM provides guidance to trustworthiness

Which of the following is the best way to decide if the findings of a research study can be generalized to your actual patient? a. Look for a compelling reason why the study results do not apply to your patient b. Use the inclusion/exclusion criteria and decide if your patient would meet them c. Contact the authors and ask them if the results would apply to your patient d. Ask your supervising physician if the results would apply to your patient

a. Look for a compelling reason why the study results do not apply to your patient

Which of the following groups should be blinded, if possible during a study? (May choose more than one correct answer) a. Patients b. Data Analysts c. Clinicians d. Data Collectors

a. Patients b. Data Analysts c. Clinicians d. Data Collectors

When we want to describe the relationship among different variables and make a PREDICTION, which of the following tests is best to select? a. Regression analysis b. Pearson Correlation

a. Regression analysis

Which of the following terms is generally considered equivalent to the Odds Ratio? a. Relative Risk b. Relative Risk Reduction

a. Relative Risk

Which of the following statements best describes the term, Numbers Needed to Harm? a. The numbers of patients who would have to be exposed to something to result in ONE additional harmful event b. The numbers of patients who would have to be exposed to something to result in THREE additional harmful events c. The numbers of patients who would have to be exposed to something to result in TWO additional harmful events d. The numbers of patients who would have to be exposed to something to result in FOUR additional harmful events

a. The numbers of patients who would have to be exposed to something to result in ONE additional harmful event

Which of the following is an example of a "Summary" resource? a. Up-to-Date b. BMJ EvidenceUpdates c. A federated search d. MEDLINE

a. Up-to-Date

In a typical meta-analysis, which of the following shapes or lines depicts the confidence interval? a. horizontal line b. vertical line c. diamond d. square

a. horizontal line

Sensitivity and specificity tell you.....

about the test in general

Descriptions of an individual patient a. Case series b. Case reports c. Cohort study d. Case-control study e. Cross sectional study

b. Case reports

Which of the following is the best first step in searching for evidence? a. Search in Up-to-Date b. Clarify the question c. Search in PubMed d. Google it

b. Clarify the question

In a systematic reviews, to what does the term heterogeneity refer? a. A person who has two identical alleles b. Inconsistency or differences among individual studies c. When a variable is associated with an undesired outcome d. A clinical problem which occurs frequently

b. Inconsistency or differences among individual studies

When the impact of treatment is expressed as the number of patients who would have to receive treatment in order to prevent an adverse event, it is referred to as which of the following terms? a. Number Needed to Harm b. Numbers Needed to Treat

b. Numbers Needed to Treat

Which of the following study designs most likely has the least bias? a. Physician preference determines who receives treatment b. Randomization determines who receives the treatment c. Patient preference determines who receives treatment

b. Randomization determines who receives the treatment

Which of the following examples is at the highest level in the hierarchy of Evidence Based Medicine (EBM)? a. Clinical case studies b. Randomized Controlled Trials c. Summaries and Guidelines d. Animal studies

b. Randomized Controlled Trials c. Summaries and Guidelines

Investigators identify exposed and non-exposed groups of patients and follow them forward in time. a. Case series b. Case reports c. Cohort study d. Case-control study e. Cross sectional study

c. Cohort study

Which of the following term is defined as, the range in which the true value of a parameter actually lies? a. Odds Ratio b. Relative Risk c. Confidence Interval

c. Confidence Interval

Which of the following best describes the method used to decide if one should trust the findings of a systematic review? a. Determine the amount of bias b. Judge the methods section c. Evaluate the credibility d. Assess the completeness

c. Evaluate the credibility

Which of the following types of graphic representations is traditionally used for the results of a meta-analysis? a. Funnel plot b. Nomogram c. Forest plot d. PICO

c. Forest plot

Which of the following Greek letters represents how chance-corrected agreement is calculated? a. Gamma b. Phi c. Kappa d. Alpha

c. Kappa

Which of the following statements best represents how you would interpret the results of a treatment study with a Relative Risk Reduction of 15% that has a Confidence Interval of -38 to 59%? a. The treatment is most likely effective b. The treatment is definitely effective c. You cannot be sure that the treatment is actually effective

c. You cannot be sure that the treatment is actually effective

Descriptions of an individual patient

case reports

The study design relies on the initial identification of patients with the outcome of interest and the selection of individuals who do not have the outcome of interest. a. Case series b. Case reports c. Cohort study d. Case-control study e. Cross sectional study

d. Case-control study

Which of the following best describes the Ottawa Ankle Rule? a. It is a physical exam similar to the anterior drawer b. It is an Evidence Based Medicine principle c. It is a clinical guideline that helps guide treatment decisions d. It is a clinical prediction rule that helps guide assessment decisions

d. It is a clinical prediction rule that helps guide assessment decisions

For which of the following biases does a funnel plot test? a. Detection b. Data Completeness c. Channeling d. Publication

d. Publication

The study design is based on an assembled population of exposed and non-exposed participants, AND the outcome is measured at the same point in time. a. Case series b. Case reports c. Cohort study d. Case-control study e. Cross sectional study

e. Cross-sectional study

To rule in a disease, you want to pick a test with the ...

largest positive likelihood ratio

What type of test would you use for the following data situation? The investigator measured the blood pressure of subjects before and after a three week course of a new drug.

paired t test

If a clinician considered all known causes

possibilistic list

If a clinician considered the most likely causes to respond to therapy

pragmatic list

If a clinician considered the more likely causes

probabilistic list

If a clinician considered the more serious causes if left undiagnosed or untreated

prognostic list

Prevalence

the proportion of persons in a population who have a disease/attribute at a given time

specificity gives you

true negative

sensitive gives you

true positive

Predictive values and likelihood ratios tells you....

what a particular test means for the patient in front of you (good for individuals)