thinking critically about clinical evidence

Question 1

what is evidence-based medicine?

Answer 1

diligent and explicit use of current evidence in making decisions about the care of individual patients

Question 2

what kind of evidence can be used in making decisions about the care of an individual?

6 types of evidence

Answer 2

• systematic reviews and meta-analyses
• RCT
• quasi-experimental
• case control studies
• cross sectional surveys
• case studies & reports

Question 3

what is a systematic review?

Answer 3

a structured method of reviewing research on a specific research question

Question 4

what are the aims of systematic reviews?

Answer 4

to identify, select, shorten and appraise primary research evidence relevant to the research question

Question 5

questions asked by systematic reviews?

2 points

Answer 5

effectiveness of intervention
comparison of interventions

Question 6

main features of systematic reviews:

4 features

Answer 6

• transparent
• comprehensive
• less subject to bias
• protocol driven

Question 7

recommended data bases to find systematic reviews:

3 websites

Answer 7

• PsycINFO
• PubMed
• Web of science

Question 8

advantages of systematic reviews

4 advantages

Answer 8

• replicability
• reducing bias
• comprehensive
• indentifies gaps with current research

Question 9

what is the Cochrane collaboration?

Answer 9

international non-profit organisation that prepares and maintains systematic up-to-date reviews of health care interventions

Question 10

what is a meta-analysis?

Answer 10

when results from individual studies are pooled to calculate the average effect size

Question 11

what do meta analyses do?

Answer 11

they summarise the effectiveness of an experimental intervention

Question 12

what does a systematic review not have to include>

Answer 12

a meta-analysis

Question 13

limitations of systematic reviews and meta-analyses?

3 limitations

Answer 13

• language bias if limited to english
• may be affected by low quality studies
• findings are not necessarily applicable to individual cases

Question 14

what are randomised controlled trials?

Answer 14

when patients are randomly assigned to a treatment or placebo group

Question 15

what is a double blind randomised controlled trial?

Answer 15

when neither patient or research knows what condition the patients are in

Question 16

what is a case control study?

Answer 16

the identification of a group of cases and a group of controls from the same population

Question 17

advantages of case control study?

Answer 17

• cost effective
• can be used to study outcomes of dieseases that are rare

Question 18

disadvantages of case control studies

2 disadvantages

Answer 18

• results may give rise to bias
• researchers need to select a suitable control group

Question 19

what is a cross sectional survey?

Answer 19

when data are collected on the whole study population at a single point in time to examine the relationship between disease and other variables of interest

Question 20

limitations of cross sectional surveys

3 limitations

Answer 20

• Unable to draw valid conclusions about any possible causality because the presence of risk factors and outcomes are measured simultaneously
• sample size needs to be large to estimate prevalence
• collection of information about risk factors is retrospective, running the risk of recall bias

Question 21

summary of the anti-psychiatry movement

Answer 21

• definitions/criteria of disorders are vague
• treatments are ultimately far more damaging than helpful to patients

Question 22

what did R.D. Laing state about psychiatry?

Answer 22

psychiatry was founded on a false knowledge: illness diagnosed by conduct but treated bilogically