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Fig. 9. Forest plot of the effects of tai chi on quality of life. (A) Physical function; (B) bodily pain; (C) social function; StudyID: study reference;
Tn: number of participants in treatment group; Cn: number of participants in control group; WMD: weighted mean difference; 95% CI: 95%
confidence interval.
efficient in improving BP and QoL-related outcomes
compared with usual care of treatments, which is in
agreement with the results of a previous study (60).
A beneficial trend was also observed in reducing FIN
(SMD –0.32; 95% CI –0.71 to 0.07; p = 0.110) and
improving balance (MD 2.71s; 95% CI –3.29 to 8.71
s; p = 0.376), although no significant difference was
achieved. One important reason for the insignificant
effects of tai chi on FIN was heterogeneity. Included
studies varied in sample size, population, types of tai
chi, intervention regimens and study design. In addition,
Fig. 10. Funnel plot of publication bias. SMD: standardized mean
difference; se(SMD): standard error of standardized mean difference.
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allocation concealment and blinding were not clear or
applied in the majority of included studies, which might
give rise to the bias. The results of the current review
are consistent with a previous study of balance (61).
When practicing tai chi, patients need to control their
body balance while continuously changing position
and bodily center of gravity. In addition, tai chi helps
improve the ability of controlling muscles and joints,
which is associated with better balance control (62).
Moreover, the results of sensitivity analysis based on
the PEDro scale score were consistent with the previous
findings, except for physical function and bodily pain,
which might be due to insufficient eligible studies.
The contrary findings indicated the results of these
two outcomes were unstable, which should be taken
into consideration when interpreting our concludions.
There are several theories that could account for the
effects of tai chi. Chen et al. (63) reported the main
beneficial effects of tai chi are to enhance metabolism,
anti-inflammatory activation and cardiopulmonary
regulation, rather than consume calories. DM was
also regarded as an inflammatory disease (27), and
previous studies have found that tai chi is beneficial
for regulatory T-cell function (64) and the reaction of
type 1 helper (Th1) cells (27). As a type of moderate
exercise, tai chi could improve basic metabolism and
it has been shown to be beneficial for glucose absorp-
tion and glycogen synthesis, which in turn benefits