Summarized Resources

Question 1

What are the 4 A’s of evidence based medicine?

Answer 1

Ask, Acquire, Appraise, Apply

Question 2

The highest level of evidence, the evidence that is most valid (free of bias)

Answer 2

“Best” Evidence

Question 3

Biased samples, unrealistic methods, and Berkson’s bias all affect

Answer 3

External Validity

Question 4

Bias from subjects or investigators, extraneous factors, and lack of randomization all affect

Answer 4

Internal validity

Question 5

Synthesize results and pull together major findings

Answer 5

“Review” Articles

Question 6

Review articles can be found in many

Answer 6

Clinical journals

Question 7

The strength of review articles are that, if done well, they provide a good discussion from experts in the field on the most important findings and

Answer 7

New directions

Question 8

What are the weaknesses of review articles?

Answer 8

They are subject to the bias of the author or the journal

Question 9

Reviews of the literature that follow a prescribed protocol to remove bias

Answer 9

Systematic reviews

Question 10

Save time and find and summarize the best evidence (When done well)

Answer 10

Systematic reviews

Question 11

Provide up to date summary of all published research literature and allow large amounts of data to be assimilated

Answer 11

Systematic Reviews

Question 12

Where do you find systematic reviews?

Answer 12

Peer-reviewed journals, or databases (Cochrane library)

Question 13

Systematic reviews define a specific

Answer 13

Question

Question 14

Find all scientific studies, select the strongest studies, and describe the scientific strength of the selected studies

Answer 14

Systematic reviews

Question 15

In a systematic review, the specific question is defined using

Answer 15

PICO

Patient (population)
Intervention (exposure, test, or other agent)
Comparison (other treatment/group)
Outcome (outcomes of clinical importance)

Question 16

You have a patient who is trying to lose weight and has decided to take up running, in hopes of running a marathon in the next year. She has a trainer, who recommends that she prevent muscle soreness by using a new whole-body cryotherapy machine that was bought by the gym. The trainer says it will prevent muscle soreness. She asks whether it would prevent muscle soreness, and whether it would be good for her. What is the PICO?

Answer 16

Patient = Adults
Interventions = Whole-body cryotherapy
Comparisons = Nothing, or other non-drug txs
Outcomes = amount of muscle soreness

Question 17

A 52 year old man reports to E.D. complaining of
worsening epigastric pain for 1 day with chronic
pain for 3 months. Nausea and vomiting for 1 day,
and no bowel movement for 1 day. History of
similar attacks increasing in frequency over the
past 3 years. Significant history of ongoing alcohol
abuse. No recent trauma. He is diagnosed with acute pancreatitis and says that he read that enteral feeding (tube feeding) may be better than the intravenous feeding. He asks you what you think. What is the PICO?

Answer 17

Patient = adult with severe acute pancreatitis 
Intervention = Enteral Feeding
Comparison = IV feeding
Outcome = Survival, disease severity, complications?

Question 18

On her routine visit to assess her asthma control, Ms. S, your 23 year old patient with persistent asthma, says that she recently heard that drinking coffee makes asthma better. She normally takes asthma control medicine and uses an inhaler a few times a week when she has a severe episode. She would like to know if drinking more coffee will reduce her need to use her inhaler. What is the PICO?

Answer 18

Patient = Adult asthma patients
Intervention = regular asthma medication plus coffee
Comparison = regular asthma medication alone
Outcomes = reduction in asthma symptomes and reduced use of inhaler

Question 19

A large, multi-site study is published that examined the effectiveness of a new drug to promote hamstring muscle healing after a strain. 100 subjects from 10 sports medicine centers are chosen and randomly assigned to receive the drug or placebo. The drug was found to work and have an added benefit. What would be an example of an extraneous factor that would be important to control in order to increase the internal validity of the study?

Answer 19

Whether people in the drug group were using other forms of medication such as non-steroidal anti-inflammatories

Question 20

In a systematic review, the purpose of finding all relevant studies and selecting the strongest studies is to get a

Answer 20

Representative sample

Question 21

The goal to finding all the studies bearing on a question is to

Answer 21

Increase sensitivity and reduce bias

Question 22

What are some methods to choosing the strongest articles?

Answer 22

Limit to RCTs and avoid observational trials, or those without a comparison group

Question 23

You should always include unpublished studies to avoid

Answer 23

Publication bias

Question 24

Bias towards publishing only positive outcomes

Answer 24

Publication bias

Question 25

A systematic review aims at examining internal validity by reviewing for bias and making sure the review includes more than one

Answer 25

Researcher

Question 26

Determining the scientific strength of the selected studies and if quality is associated with results is how systematic reviews examine

Answer 26

Internal validity

Question 27

Weaker studies tend to have better

Answer 27

Effect sizes

Question 28

In a Forest-plot, the size of the square is proportional to the

Answer 28

Number of people in the sample

Question 29

In a Forest-plot, the line length represents the

Answer 29

CI (larger means more variability/error)

Question 30

If results are similar, they can be pooled and analyzed together in a

Answer 30

Meta-analysis

Question 31

Pooled results are weighted by sample size. What are the two models?

Answer 31

Fixed effect model and random effect model

Question 32

When studies ask the same question

Answer 32

Fixed effect model

Question 33

Assumes studies are asking different questions but are somewhat similar

Answer 33

Random effect model