WorksheetsMCQ Module 2
Total questions: 10
Worksheet time: 7mins
External validity refers to:
How 'good' or 'true' the results of a study are based on the limitation of potential bias in the
study design and methods
The generalizability of the findings to the 'real world' population of interest not under strict
'experimental' control
How credible the results of a randomized controlled trial are
Detection bias is:
Present when there are more than 5 time points at which outcomes are measured
Present when different assessors collect outcome data
Present when systematic differences are identified in how the data is collected between
groups
All of the above
Whilst undertaking critical appraisal, to determine that there has been an attempt
on the part of the researchers to limit attrition bias you may look to see that:
A per protocol analysis has been performed
The study is less than 8 weeks duration to limit losses to follow up
An available case analysis has been performed
An intention- to-treat analysis has been performed
A quasi-randomized controlled trial is named as such because:
Opaque sealed envelopes weren't used for allocation of subjects to groups
A systematic but non-random method was used to allocate subjects to treatment groups
Participants were not blinded to their treatment allocation
All of the above
Confounding occurs:
When the effects of two or more processes are not separated, so the apparent effect is not
the true effect
When investigators mix up the data collection by accident
When there is systematic deviation of the results or inferences from the truth
Most commonly in randomized controlled trials
Which of the following is an absolute rather than relative measure of difference?
Relative Risk
Odds ratio
Risk difference
Hazard ratio
When dealing with meta-analysis of continuous data, an effect measure you may
calculate is the:
Odds ratio
Relative risk
Standardized mean difference
Meta-analysis should only be undertaken:
On randomized controlled trials
Normally, only in the presence of clinical and methodological homogeneity
Where the studies to be included have similar sized populations
A sensitivity analysis may be performed during a systematic review to:
See how sensitive the data is to the normal distribution
To test the assumptions or decisions made by the reviewers
Increase external validity of the findings of the review
To minimize error during the data extraction process, reviewers can:
Use a specialized data extraction form
Pilot test the data extraction form prior to use for the review
Train and assess all people involved in the data extraction process
Have blind extraction of the data from each study by two people
All of the above
