Good Critical Appraisal Skills Programme (Casp) Critical Thinking Example

You are required to complete a critical appraisal of the following publication using the CASP checklist for randomised controlled trails in this proforma.

Citation of the RCT to be reviewed:

Olumide F, Newton JT, Dunne S, Gilbert DB. 2009. Anticipatory anxiety in children visiting the dentist: lack of effect of preparatory information. Journal of Paediatric Dentistry 19,338-42.
CASP checklist:
Ten questions are provided to assist you to think systematically.
The first two issues can be answered quickly since they are screening questions.
If the answer to both is “yes”, it is worth proceeding with the remaining questions.
Most questions will require you to record a “yes”, “no” or “can’t tell” .. A number of italicised prompts are given after each question. These are designed to remind you why the question is important. Record your reasons for your answers in the spaces provided.
The ten questions are adapted from Guyatt GH, Sackett DL, and Cook DJ, Users.'
Guides to the medical literature. II. How to use an article about therapy or prevention.
JAMA 1993; 270 (21): 2598-2601 and JAMA 1994; 271(1): 59-63.
© Public Health Resource Unit, England (2006). All rights reserved.
No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior written permission of the Public Health Resource Unit. If permission is given, then copies must include this statement together with the words “© Public Health Resource Unit, England 2006”. However, NHS organisations may reproduce or use the publication for non-commercial educational purposes provided the source is acknowledged.
© Public Health Resource Unit, England (2006). All rights reserved.
Please use font Arial size 11 to complete this proforma. Please do not exceed the word limit for the Summary of the Paper and please do not exceed the space provided in the boxes. Anything outside the boxes will NOT be marked.
A hard copy of this report must reach the Student Education Office by 9th March 2015 by 12pm. Please also submit an electronic copy through Turnitin for plagiarism checking.
Summary of the Paper (500 words maximum)
Screening Questions
Was the question asked in the study clearly focused?
Yes Can’t tell No
Consider if the question is ‘focused’ in terms of:
– the population studied
– the intervention given
– the outcomes considered
Was the study a randomised controlled trial (RCT) and was it the appropriate approach?
Yes Can’t tell No
Consider:
– The reasons for carrying out this as an RCT
– Which would be the right approach to research the question asked?
Is it worth continuing?
Yes No
Detailed Questions
3. How appropriate was the allocation of the participants into the intervention and control groups?
Yes Can’t tell No
Consider:
– How random was the process of participant allocation to their respective groups?
– What method was used to allocate the participants? Was there any balancing carried out?
– Describe how randomization was carried out and also the process of allocating participants to the groups.
– Were the groups well balanced? Were there any incidents of participants changing their groups between the entry and trial period?
– Were there any differences observed which could explain confounding outcomes?
4. Were the participants and staff involved masked from knowing the participant group?
Yes Can’t tell No
Consider:
– The possibility of blinding in the trial
– The extent in which blinding was eliminated
– Was blinding significant in this study?
– Any instances of observer bias
5. Were all participants in the trial well accounted for in the end?
Yes Can’t tell No
Consider:
– The possibility of participants changing from the experimental to the control group and vice versa
– If there was loss-to-follow-up, whether all participants were followed up
– Was it an intention-to-treat analysis? Were all participants analysed in their respective groups to which they belonged?
– Is there any additional information that could make the results more satisfactory?
6. Were follow-ups made on all participants in the group and data collected in the same way?
Yes Can’t tell No
Consider:
– If the participants were reviewed at the same time and the kind of attention they received from the researcher, dental nurse and the analyst. Differences in the attention given could result in performance bias.
7. Was the number of participants in the play enough to minimize the possibility of chance?
Yes Can’t tell No
Consider:
– If a power calculation was carried out. A power calculation estimates the number of participants needed to be reasonably sure to obtain reasonably measurable units (if a measurable unit really exists and for a given percentage of uncertainty about the result).
8. by which format were the results in the outcome presented?
Consider:
– if, for instance, the outcome was presented as a sample of people going through a given situation, such as a risk, or the outcome is a statistical measurement such as differences in mean or median, or even as hazards and survival curves.
– What was the size of the outcome and its significance in the trial
– How you would conclude the result of the trial in a brief statement
9. How precise were the results?
Consider:
– if a decision could be inferred from the results depending on their precision
– If any other statistical representations like a confidence interval were included. What relation would your decision be between the upper confidence limit and the lower confidence limit?
– if p-values were is reported in the absence of confidence intervals
10. Were all pertinent findings included so the results can be applied?
Yes Can’t tell No
Consider whether:
– the participants in the trial differed significantly with your population to an extent of bringing difference in results
– the differences between your local setting and the setting of the trial are significant
– the same treatment could be offered in your local setting
Also Consider the outcomes from the point of view of:
– the individual
– policy makers and medical practitioners
– family/caregivers
– the community at large
Also Consider whether:
– any reported benefit outweighs any cost or harm. Can this information be obtained elsewhere?
– the result of this trial can lead to a policy change.