Critical Appraisal | Research Paper

Running head: CRITICAL APPRAISAL
Critical Appraisal
Name of the Student
Name of the University
Author Note

CRITICAL APPRAISAL1
Aim of the researches:
Aim of the first research paper (Derry et al., 2015) is to compare Hatha yoga
intervention between trial group and wait-list control group of survivors of breast cancer to
reduce cognitive complaints through randomized trial group. Aim of the second paper
(Kiecolt-Glaser et al., 2014) is to assess the impact of yoga in reducing inflammation, fatigue
and mood changes through randomized controlled trial.
Comparison groups:
The papers contain comparison groups which are trial group undergoing Hatha yoga
intervention after surviving from breast cancer and a wait-list control group who have not
received the yoga intervention and are selected randomly to be waiting.
Circumstances and methods:
In the first paper, selections of 200 random breast cancer survivors from breast
cancer groups, clinics and physicians and through announcement in the community. The
women of trial group was reported to be participating in the 12-week yoga intervention
whereas the control group refrained from participating in yoga intervention with time. The
trial group and the control group after 3 months follow-up were asked to fill up
questionnaires and give blood samples with morning fast. In the second research paper, 200
participants of age 27-76 years comprising of breast cancer stage 0 to stage IIIa survivors
who had completed their intervention for cancer 3 years back and surgery 2 months back
were enlisted. Breast cancer groups, community and web-based announcements, and
references from oncologists was used. Similar to the first research paper the trial group was
assigned to participate in yoga and the control group participants were asked to refrain from
joining yoga.

CRITICAL APPRAISAL2
Follow-up:
The follow up for the second research was sufficiently complete and the authors
followed the CONSORT diagram to assess the participants follow-up intervention and
screening them throughout the randomization but follow up was not 100% (Consort-
statement.org., 2020). The follow up was done for both the trial and the control group which
showed that analysis at the end of intervention contained 96% of participants in trial group
whereas 90% in the control group during follow up intervention. The first research provided
no clear follow-up data.
Association between exposure and outcome:
Both papers did not calculate relative risk, hazard risk and odd-ratio between the
exposure and the outcome. However the strength of association between the yoga practice
and cognitive problems after 3 months of follow-up intervention were significantly higher
with a p-value less than 0.05 (p<0.001). Since it was a randomized trial study, it does not
include odd-ratio measure. 95% CI was considered where the population size was within the
interval (Walsh et al., 2014). In the second study, the association between yoga practice and
outcome measures that is inflammation, fatigue and mood was statistically significant and
stronger association was found for both groups between yoga and fatigue (p =0.19), and
vitality (p =0.016, p =0.0045) but lower significance of association between yoga and
depression (p >0.2) for both the trial and control group. It was also observed that during the 3
months follow-up, gradual increasing exposure led to the decrease in proinflammatory
cytokine production- IL-1(p = 0.3), IL-6 (p = 0.1) but not for TNF-α (p >0.5).
Calculation for exposure/outcome
The calculations for exposure/control event rates, ARR, NNT, RR, RRI was not
provided for both the researches. The baseline study was used in the first study. Breast