Evidence Selection and Critical Appraisal using CASP (Article Sample)

EVIDENCE BASED PRACTICE
Assessment Item 2: Evidence Selection and Critical Appraisal using CASP
PART 2: Completed CASP tool for selected article
CHOSEN ARTICLE:
Nahas R. Complementary and alternative medicine approaches to blood pressure reduction: An evidence-based
review. Canadian Family Physician. November 2008;54 (11):1529-1533.
SCREENSHOT:


CASP Systematic Review Appraisal Tool
Section A: Are the results of the review valid?Screening Questions
1. Did the review address a clearly focused issue?
√ Yes No Can’t tell
In general, the reviewer provided enough information in order to clearly focus on the issue: Complementary and Alternative medicine (CAM) approaches to high blood pressure (BP) reduction. Not much specific information was provided for the population being studied though, since he only mentioned, “patients with hypertension” without any demographics such as age, gender, race, etc. The intervention given was provided with Level 1 evidence (shown in table form), although some had limitations as to its methodology but the administration, duration and dosing of therapy were specified in each study so these are reliably determined by the reviewer. The outcome variable was very much considered as to the largest BP reduction so it was measured and specified.
2. Did the authors look for the right type of papers?
√ Yes No Can’t tell
Justify your answer:
The reviewer comprehensively provided the right type of papers to address the review question since most studies reviewed were Randomized controlled trials (RCTs). RCTs are the appropriate study design and thus provided the most reliable results as to the intervention`s effectiveness.


Detailed questions
3. Do you think the important, relevant studies were included?

Yes No √ Can’t tell
Justify your answer:
In this evidenced-based review, the author used MEDLINE and EMBASE and he searched from January 1966 to May 2008 combining key words so the search method was explicitly stated and the reader can assess immediately that no relevant research has been omitted. The author could have used more databases like LILACS and Cochrane
so the more likely it is that relevant studies will not be omitted. These databases would ensure that there is little probability that relevant studies have been omitted. Finally, this was a comprehensive review as to the inclusive dates hence it is complete and updated.
4. Did the review’s authors do enough to assess the quality of the included studies?

Yes √ No Can’t tell
Justify your answer:
In this review, the author did list only 3 assessments as to the quality of evidence included among the 8 CAM approaches evaluated:
Chocolate- the meta-analysis was statistically rigorous; 2 authors reviewed each of the studies and
their methodologic quality (Jadad scale score of 8 to 10 out of 13).
Coenzyme Q10- a meta-analysis evidenced from a large, prospective, multicentre trial
Mind-body - two systematic reviews , the first examined 12 RCTs while the second meta-analysis
examined 9 RCTs
Thus, only in the meta-analysis for chocolate it is stated that two reviewers evaluated the quality of each studies independently, and the methodologic quality was reported.
5. If the results of the review have been combined, was it reasonable to do so?
√ Yes No Can’t tell
Justify your answer:
The result from the individual studies from this evidenced-based review were clearly displayed and the an agreement on the efficacy of CAM to reduce high BP were clearly shown though they do not agree on the magnitude of its effect. This is a good evidenced-based review since these differences were identified and explained by the reviewer. Hence, it was reasonable to do so.

Section B: What are the results?6. What are the overall results of the review?
Justify your answer:
The overall results of the review for CAM approaches to lower BP shows the best supported exists for dark chocolate, coenzyme Q10, Qigong, slow breathing techniques, and meditation. The largest BP reduction was seen with use of coenzyme Q10 with BP decreased by 16.6/8.2 mm Hg (P<.001).
7. How precise was the estimate of the treatment effect?
Justify your answer:
The author of this evidence-based review presented the results as relative risks with their respective confidence intervals s...