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RESEARC H ARTIC L E Open Access
The evidence for Shiatsu: a systematic review of
Shiatsu and acupressure
Nicola Robinson
1†
, Ava Lorenc
1*†
and Xing Liao
2†
Abstract
Background: Shiatsu, similar to acupressure, uses finger pressure, manipulations and stretches, along Traditional
Chinese Medicine meridians. Shiatsu is popular in Europe, but lacks reviews on its evidence-base.
Methods: Acupressure and Shiatsu clinical trials were identified using the MeSH term ‘acupressure’in: EBM reviews;
AMED; BNI; CINAHL; EMBASE; MEDLINE; PsycARTICLES; Science Direct; Blackwell Synergy; Ingenta Select; Wiley
Interscience; Index to Theses and ZETOC. References of articles were checked. Inclusion criteria were Shiatsu or
acupressure administered manually/bodily, published after January 1990. Two reviewers performed independent
study selection and evaluation of study design and reporting, using standardised checklists (CONSORT, TREND,
CASP and STRICTA).
Results: Searches identified 1714 publications. Final inclusions were 9 Shiatsu and 71 acupressure studies. A quarter
were graded A (highest quality). Shiatsu studies comprised 1 RCT, three controlled non-randomised, one within-
subjects, one observational and 3 uncontrolled studies investigating mental and physical health issues. Evidence
was of insufficient quantity and quality. Acupressure studies included 2 meta-analyses, 6 systematic reviews and 39
RCTs. Strongest evidence was for pain (particularly dysmenorrhoea, lower back and labour), post-operative nausea
and vomiting. Additionally quality evidence found improvements in sleep in institutionalised elderly. Variable/poor
quality evidence existed for renal disease symptoms, dementia, stress, anxiety and respiratory conditions. Appraisal
tools may be inappropriate for some study designs. Potential biases included focus on UK/USA databases, limited
grey literature, and exclusion of qualitative and pre-1989 studies.
Conclusions: Evidence is improving in quantity, quality and reporting, but more research is needed, particularly for
Shiatsu, where evidence is poor. Acupressure may be beneficial for pain, nausea and vomiting and sleep.
Background
Shiatsu is a form of complementary and alternative
medicine (CAM) which primarily developed in Japan
[1]. Both Shiatsu and acupressure have roots in Chinese
medicine and embrace the philosophy of Yin and Yang,
the energy meridians, the five elements and the concept
of Ki, or energy. This concept of affecting the balance of
energy through acupoints on the meridians is similar to
acupuncture where needles or heat is applied to acu-
points [2]. ‘Shiatsu’literally means “finger pressure”,but
uses gentle manipulations, stretches and pressure using
fingers, thumbs, elbows, knees and feet. Shiatsu
incorporates acupressure, which is similar but applies
pressure for longer on specific pressure points on meri-
dians, following Traditional Chinese Medicine (TCM)
theory. Shiatsu tends to cover the whole body[3].
Shiatsu diagnosis is primarily through touch, rather than
TCM which primarily uses the pulse diagnosis and
inspection of the tongue. Shiatsu practitioners are
trained in the anatomical location, functions and uses
over 150 pressure points on the body. Evidence for the
efficacy of acupressure may therefore potentially support
claims about the efficacy of Shiatsu [4].
Shiatsu is practiced in many European countries but
varies in styles, philosophical approaches and theoretical
bases. The approaches most commonly found in Britain
are Zen Shiatsu, Macrobiotic Shiatsu, Healing Shiatsu,
Tao Shiatsu, Seiki, Namikoshi Shiatsu and Hara Shiatsu)
[3,5].
* Correspondence: lorenca@lsbu.ac.uk
†Contributed equally
1
Allied Health Sciences Department, Faculty of Health and Social Care,
London South Bank University, 103 Borough Road, London SE1 0AA, UK
Full list of author information is available at the end of the article
Robinson et al.BMC Complementary and Alternative Medicine 2011, 11:88
http://www.biomedcentral.com/1472-6882/11/88
© 2011 Robinson et al; licensee BioMed Central Ltd. This is an Open Access article distr ibuted under the terms of the Creative
Commons Attri bution License (http://creativecommons.org /licenses/by/2.0), which permits unrestricte d use, distribution, and
reproductio n in any medium, provided the original work is properly cited.
Shiatsu aims to balance, restore and maintain the
body’s energy balance and prevent the build up of stress
in the UK. The most common conditions presenting for
treatment are musculo-skeletal and psychological pro-
blems[6]. Health problems which may be amenable to
treatment by Shiatsu include: headaches, migraine, stiff
necks and shoulders, backaches, coughs, colds, men-
strual problems, respiratory illnesses including asthma
and bronchitis, sinus trouble and catarrh, insomnia, ten-
sion, anxiety and depression, fatigue and weakness,
digestive disorders and bowel trouble, circulatory pro-
blems, rheumatic and arthritic complaints, sciatica and
conditions following sprains and injuries [3]. Shiatsu is,
however, a holistic therapy and often also impacts a
patient’s well-being, lifestyle, diet, body/mind awareness
[7]. Shiatsu is commonly used by older (median age of
50 in the UK) females [7].
This review aimed to identify the evidence base
informing the practice of Shiatsu. Due to the lack of
Shiatsu specific literature and overlap in practice and
theory, acupressure studies were also included. Although
there are a number of systematic reviews for acupres-
sure,theyweremostlyconfinedtoasingle(Western)
condition such as nausea and vomiting [8] or dysmenor-
rhoea [9].
Objectives
To systematically review all papers using Shiatsu or acu-
pressure for any health condition for any population,
using either a systematic review/meta-analysis, RCT,
quasi-experimental, or uncontrolled design.
Methods
Eligibility criteria
Inclusion criteria were:
•Shiatsu or acupressure administered manually/
bodily
•Meta-analysis, systematic review or clinical trial
•Published after January 1990
Exclusions were:
•Guidelines for treatment, reports of possible
adverse events, surveys, case reports/series, non sys-
tematic reviews, qualitative studies, conference
abstracts/posters
•Newspaper articles, book reviews, ‘popular’health
publications, general comments or letters.
•Papers included in systematic reviews included in
this review
•Papers in a language other than English
•Use of plasters, devices, or wristbands
•Acupressure on auricular or Korean points/
meridians
Information sources
Databases searched were: EBM reviews (includes all
Cochrane Library resources); Allied and Complementary
Medicine (AMED);British Nursing Index (BNI);Cumula-
tive Index to Nursing & Allied Health Literature
(CINAHL); EMBASE; MEDLINE; PsycINFO/PsycARTI-
CLES; Science Direct; Blackwell Synergy; Ingenta Select;
Wiley Interscience; Index to Theses and ZETOC (British
Library electronic table of contents). In addition the
references of retrieved articles were checked to identify
any further studies.
Search
The MeSH term tree ‘acupressure’was used which
incorporates Shiatsu. For databases not using MeSH
terms, ‘shiatsu’or ‘acupressure’were used.
Study selection
Study selection was independently performed by two
reviewers using the inclusion/exclusion criteria given
above, followed by discussion and consensus within the
research team. The first stage of selection used the
abstracts, the second stage the full text of the papers.
Data collection process
For each study the following data was extracted inde-
pendently by two reviewers using a standardised extrac-
tion form. Any disagreements were moderated by a
third reviewer.
•Authors
•Date
•Study design (meta analysis, systematic review, ran-
domized controlled trial, case control trial or uncon-
trolled study)
•Health condition
•Setting
•Sample
•Intervention
•Outcome measures
•Results
•Conclusion
Quality assessment
The contribution made to the evidence base by each
study, based on the study design, rigour of methods and
reporting, was evaluated independently by two
reviewers, with an independent adjudicator. Studies
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were evaluated on the following quality indicators to
determine its contribution to the evidence base:
•The rigour of the study conducted was determined
using a critical appraisal checklist [10]
•Adapted STRICTA score for quality of reporting of
the intervention (acupressure only, not Shiatsu) for
each study [11] (reported as a score out of 16 rele-
vant items - item 2 g on STRICTA, needle type was
not relevant)
•Quality of reporting, assessed using established
checklists: CONSORT guidelines for RCTs[12];
CASP guidelines for systematic reviews [13]; and
TREND statement for non-randomised studies [14].
•Study design (according to the hierarchy meta-ana-
lysis > systematic review > RCT > controlled trial >
uncontrolled trial), as discussed in the NICE guide-
lines manual, section 6 [15].
Studies were graded A (good), B (fair/moderate) or C
(poor) depending on these indicators. Results of this
evaluation are given for each study in Additional file 1.
Synthesis of results
Studies were grouped into either Shiatsu or acupressure
and within these categories according to health condi-
tion treated. For each health condition evidence was
categorised according to criteria from Waddell [16].
Category 1: Generally consistent finding in a range of
evidence from well-designed experimental studies
Category 2: Either based on a single acceptable study,
or a weak or inconsistent finding in some multiple
acceptable studies.
Category 3: Limited scientific evidence, which does
not meet all the criteria of acceptable studies, or an
absence of directly applicable studies of good quality.
This includes published and unpublished expert opinion.
This review has been reported according to the princi-
ples in the PRISMA statement [17] and acupoints are
reported using the WHO system [18]
Results
Study selection
After carrying out the database searches, a total of 1714
publications were identified (Figure 1). After duplicate
items, newspaper articles and commentaries were
removed 1285 items remained. From screening the
abstracts 933 articles were excluded. Two reviewers
screened the full texts of the remaining 351 articles
using exclusion criteria and quality assessment and
excluded 206. Of those remaining, 56 were used for
background information only, leaving 89 studies. A
further 9 were excluded as they were already included
in systematic reviews included in this review. The total
included studies were 9 Shiatsu and 71 acupressure
publications.
Details of included studies are presented in Additional
file 1, grouped by health condition. Just under one third
(27.5%) were graded A (highest quality), 42.5% graded B
and 26.3% C (lowest quality) (3 studies were ungraded);
this grading refers to the contribution the study made
to the evidence, which took into account study design,
rigour and reporting.
Shiatsu
Only 9 Shiatsu studies were of sufficient quality to be
included in the review. These comprised 1 randomised
controlled trial (RCT), three controlled non-randomised,
one within-subjects trial, one observational study and 3
uncontrolled studies. These studies investigated quite
separate health issues, did not use comparable metho-
dology and data could not be pooled due to their het-
erogeneity. Subjects were chronic stress, schizophrenia,
promoting well-being and critical health literacy, angina,
low back and shoulder pain, fibromyalgia, chemotherapy
side effects/anxiety and inducing labour. They are
grouped by methodology and discussed below.
One RCT was identified (integrated care, which
included Shiatsu), for back and neck pain [19]. No sig-
nificant effects, compared to standard care were identi-
fied. The study used a fairly large sample (n = 80) but
was underpowered to detect any statistically significant
effects.
Three studies compared two or more treatments with
non-random group allocation, rather by preference [20],
participants in another study [21] or staff on duty [22].
Figure 1 Flowchart of study selection.
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Lucini et al [20] evaluated Shiatsu for chronic stress; 70
volunteer patients chose either active (relaxation and
breathing training), passive (Shiatsu) or sham treatment
(stress management information). Small sample, limited
the validity of results. Although the design accounted
for patient preference, results were confounded by more
stressed patients choosing sham. Ingram [22] compared
Shiatsu to no intervention for post-term pregnancy in
142 women. The Shiatsu group was significantly more
likely to labour spontaneously than the control (p =
0.038) and had a longer labour (p = 0.03), but groups
were allocated according to which midwife was on duty
(although groups were homogenous for maternal age,
parity and delivery details). Ballegaard et al [21] con-
ducted a study of cost-effectiveness and efficacy of
Shiatsu for angina pectoris. Sixty-nine consecutive
patients were treated and compared with those from a
separate trial of two invasive treatments for angina[23].
Incidence of death/myocardial infarction (MI) was 7% in
this sample, compared to 21% and 15% in the compari-
son group with no significant difference in pain relief.
Additionally a cost-saving of $12000 per patient was
estimated. The groups were from different countries
(USA and Denmark), additionally 56% of the partici-
pants would have been excluded from the one of the
comparison groups. It also used a convenience and
unpowered sample and no blinding.
One study used a within-subjects repeated measures
design, comparing Watsu (water Shiatsu) with Aix mas-
sage for fibromyalgia syndrome [24]. A significant
improvement was seen after treatment with Watsu (p =
0.01) for SF-36 subscales of physical function, bodily
pain, vitality and social function, but not for Aix. The
repeated measures design with counterbalancing should
reduce carryover effects although order effects may have
occurred due to high dropout. In addition it used a
volunteer sample.
Three studies had no separate control group, using a
single group pretest-posttest design[25-27], limiting the
validity of results. Lichtenberg et al’s [27] pilot study of
Shiatsu for schizophrenia showed significant improve-
ments on scales relating to illness, psychopathy, anxiety,
depression and others (p values ranged from 0.0015 to
0.0192). Brady et al [26] tested Shiatsu for lower back
pain in 66 volunteers. Pain and anxiety significantly
decreased after treatment (p < 0.001), which did not
change when demographic variables were controlled for.
Iida et al [25] investigated the relaxation effects of
Shiatsu on anxiety and other side effects in 9 patients
receiving cancer chemotherapy. The small and self-
selected samples and lack of control group in these stu-
dies limits the quality and generalisablity of the results.
In addition 13 of Brady et al’s [26] participants had pre-
viously received Shiatsu
Long (2008) conducted a prospective observational
study of 948 patients of Shiatsu practitioners in 3 differ-
ent countries[7]. Significant improvement in symptoms,
especially for tension or stress and structural problems
(effect size 0.66 to 0.77) were demonstrated. This study
is of greater quality than other Shiatsu studies as the
sample size was powered and it used a longitudinal and
pragmatic study design. For a longitudinal observational
design, this study had a good response rate (67% of
patients on average returned all questionnaires). Recruit-
ment of patients was through practitioners, who
received a rigorous training and kept a recruitment log.
Confounding factors are reported and outcomes were
accurately measured. However, data on non-respondents
or those who refused to participate were not reported
so evaluation of response bias is problematic.
Sundberg et al [19] and Ballegaard [21] used a prag-
matic design - Shiatsu as part of an integrated model of
healthcare or with other interventions (acupuncture and
lifestyle adjustment). This reflects normal practice but
specific effects of Shiatsu cannot be isolated.
There was insufficient evidence both in quantity and
quality on Shiatsu in order to provide consensus for any
specific health condition or symptom.
Acupressure
Of a total of 71 included studies described as giving
acupressure as an intervention, 2 were meta-analyses, 6
systematic reviews, 39 RCTs, five crossover trials, 5
within-subjects trials, 5 controlled non-randomised, 7
uncontrolled trials and 1 prospective study. These are
summarised by health condition below.
Pain
Pain was the most common issue addressed by acupres-
sure studies and covered a range of topics. This
included a systematic review, six RCTs with control
groups and random assignment; 2 with non-randomised
control groups or within-subject controls, and the
remainder either did not have a control or random
assignment. Overall, the evidence for the efficacy of acu-
pressure for pain is fairly strong and can be graded as
category 1 evidence. Although some studies had metho-
dological flaws, studies consistently show that acupres-
sure is more effective than control for reducing pain,
namely dysmenorrhoea (acupressure at SP6) [9,28-30],
lower back pain [31-33] and labour pain [34,35]. The
evidence for minor trauma [36,37] and injection pain
[38,39] is less conclusive and the evidence for headache
is insufficient [40]. Each pain condition is discussed
below.
Dysmenorrhoea
Of 4 papers for dysmenorrhoea, 1 was a systematic
review 2 were RCTs, and one non equivalent control
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group. All studied school or university students, with
sample sizes ranging from 30 to 216. Two used acupres-
sure on SP6, The other used a combination of points.
Both of the RCTs [28,30] compared acupressure to rest,
which does not control for the placebo effect. Jun et al
[29] compared acupressure to light touch, potentially
controlling for non-specific effects but used sequential
allocation which may create bias, although groups were
homogenous in baseline demographics and dysmenor-
rhoea factors. All studies found a significant reduction
in pain. Studies were generally good quality, with low
attrition rates and validated measures (usually VAS).
Only including students may limit generalisability and
create Hawthorne bias. Acupressure procedure was gen-
erally well-reported; all studies reported 12 or 13
STRICTA items.
Labour pain
Two of the three studies of acupressure for labour pain
were RCTs [34,35]. They both compared acupressure to
touch, thus controlling for the effect of human touch;
Chung et al [34] additionally had a conversation only
control group. The third was a one group uncontrolled
study [41]. Two studies usedLI4 [34,41]; Chung et al
[34] additionally used BL67; Lee et al used SP6 [35]. All
studies found acupressure significantly reduced pain,
Back and neck pain
Four studies on back or neck pain were identified, all
RCTs and conducted by two groups of researchers,
Hsieh et al [31,32] and Yip and Tse [33,42]. Hsieh et al
unusually used a pragmatic design of four weeks of indi-
vidualised acupressure compared to physical therapy.
They also used powered samples, blinding where possi-
ble, valid outcome measures and intention to treat ana-
lysis to protect against attrition bias. A no treatment
group was not included, limiting assessment of specific
effects. Yip and Tse also compared acupressure to usual
care, although an acupressure protocol was used. They
also had powered sample sizes but no blinding. Compar-
ison groups of aromatherapy and electroacupuncture,
limit specific effects of acupressure. All four studies
showed a significant reduction in pain.
Minor trauma
Two double-blind RCTs evaluated acupressure for
minor trauma pain during ambulance transport [36,37].
Both used sham acupressure as a control, with Kober et
al [36] additionally comparing to no treatment. Both
studies showed significant reductions in pain, anxiety
and heart rate. Limitations include fairly small sample
and lack of no-treatment control.
Injection pain
Two studies evaluated acupressure for pain of injection
[38,39]. Both studies showed reduction in pain but both
weresubjecttolimitations-Araietal[39]only
included 22 subjects although it was powered and
randomised, with a sham treatment; Alavi et al’s [38]
trial was larger and randomised, but used a within-sub-
jects crossover design which can create practice bias.
Headache
Only one study investigated headache [40], comparing a
course of 8 sessions of acupressure to medication, which
reduced pain. Although this used an RCT design, power
calculation, intention-to-treat analysis, blinding and long
follow up, there is very little detail on intervention (only
7 STRICTA items), randomisation, recruitment or
limitations.
Dental pain
One RCT for dental pain [43] compared acupressure at
LI4 to medication or sham acupressure, showing reduc-
tion in pain 4 and 24 hours after the first orthodontic
treatment but not after second treatment. Although an
RCT and well reported, only 23 patients completed the
study, despite a power calculation specifying a sample of
156.
Nausea & vomiting
Nausea and vomiting (N&V) was the second most com-
monly investigated health issue. The evidence was some-
what inconsistent and varied with type of nausea
investigated. Post-operative nausea had strongest evi-
dence, graded as Category 1 evidence mainly due to a
Cochrane systematic review and update [8,44] and a
meta-analysis [45]. The two systematic reviews [46,47]
of chemotherapy-induced N&V give additional quality
evidence, although little is true acupressure. Little reli-
able evidence is added by the RCT [48]. The three stu-
dies of acupressure for nausea in pregnancy are of
variable quality. Although one has a small sample and
uncontrolled study design [49], a well conducted RCT
[50]and meta analysis [51] provide Category 2 evidence
for nausea in pregnancy.
Post-operative
A Cochrane review [44] (update of a previous review
[8]) and meta-analysis [45] indicate the extensive evi-
dence for acupressure in treating postoperative N&V.
All the studies in the review and the majority in the
meta-analysis used acupoint PC6. The review concluded
that acupressure reduced the risk of both N&V com-
pared to sham, and reduced the risk of nausea but not
vomiting compared to antiemetic medication. The meta-
analysis concluded that all modalities of acupoint stimu-
lation reduced postoperative N&V compared to control,
and were as effective as medication. Both reviews were
very high quality with comprehensive search terms and
pooling of data.
Chemotherapy
Acustimulation, including acupressure, for nausea as a
side-effect of chemotherapy also has been reported in a
Cochrane review [46], as well as an RCT published
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subsequently [48] and a non-randomised trial [52]. Chao
et al [47] also covered N&V as part of their review of
adverse effects of breast cancer treatment.
The Cochrane review identified 11 trials and pooled
data demonstrated significantly reduced vomiting but
not nausea [46]. It was very good quality, with inten-
tion-to-treat analysis of pooled data and controlling for
duplicate and language bias.
TheRCT(n=160)[48]wasbasedonapilot[53]
included in the Cochrane review. It found significant
reductions in delayed N&V but not acute N&V, results
facilitated by the unusually long follow-up period. The
main limitations are the lack of sample size calculation
(despite conducting a pilot study) and patients breaking
the blind.
The non randomised study [52] of self-acupressure on
PC6 compared to anti-emesis medication found signifi-
cant reductions in severity of N&V, duration of nausea
and frequency of vomiting compared to control. How-
ever, these results are limited by a small and conveni-
ence sample.
Pregnancy
Three studies investigated N&V in pregnancy: one RCT
[50]; one uncontrolled study [49] and one meta-analysis
[51]. All used acupressure on PC6 (neiguan).
As concluded by the meta-analysis [51], the RCT
found improvements compared to sham or control. Shin
et al’s RCT [50] is excellent quality with double-blind-
ing, powered sample size, objective and subjective out-
comes and good reporting. Markose et al [49] also
found improvements in nausea, vomiting and retching,
but due to lack of control group, small sample, high
attrition and poor reporting the evidence is limited.
The meta-analysis included studies on all forms of
acustimulation and was generally well conducted,
although it did not attempt to find unpublished material
and only 3 databases were used.
Renal disease
Five papers (based on four RCTs) investigated the use of
acupressure for symptoms of renal disease. Due to lim-
itations, repeated in all studies due to the common
research team, evidence is category 2. Three compared
acupressure to sham points/electrical stimulation and to
usualcare[54-56],thefourthtousualcareonly[57].
The studies used different points for different symp-
toms, including fatigue [55,57], depression [56,57] and
sleep [54,56]. All studies showed improvements com-
pared to control but also found improvements in the
sham/electrical stimulation group compared to control,
suggesting that the effects of acupressure on these
symptoms are non-specific. Sample sizes were between
62 (powered) and 106 and had low attrition rates. One
study used blinding [54], the others may have been
subject to placebo or observer bias. Between 9 and 15
STRICTA items were reported and interventions and
outcome measures were validated.
Sleep and alertness
Five studies investigated acupressure for sleep in elderly
long term care facilities [58-62], and one investigated
alertness in the classroom [63]. Evidence for improving
sleep quality in institutionalised elderly is consistent
from a number of high quality studies and is category 1.
Four of the sleep studies were RCTs [59-62], an addi-
tional single-group pilot study of only 13 people contri-
butes little to the evidence base [29]. The four RCTs all
used different acupoints. Two compared acupressure to
sham points and control (conversation [62]or routine
care [60]) but only one found significant improvements
in sleep for acupressure compared to sham [62], giving
limited evidence for specific effects. Three of the studies
had powered and randomly selected samples (between
44 and 246) [60,62], validated procedure [62], intention-
to-treat analysis or triple blinding [60].
The one study on alertness in the classroom [63]was a
crossover study, randomly assigning 39 students to
either stimulation-relaxation-relaxation or relaxation-sti-
mulation-stimulation. Compared to relaxation, stimula-
tion acupressure improved alertness. Although students
were blinded, the majority correctly discerned the treat-
ment. This did not significantly affect the results,
although it raised p to 0.0484. Potential Hawthorne
effect, small sample size (39) and low generalizability
reduce the quality. Crossover design should reduce
effects of retesting, carryover or time-related effects,
although practise effect may be present (especially with
self-report).
Mental health
Five studies investigated mental health, specifically
dementia [64,65] and stress or anxiety [66-68]. The
quality was very variable, with two pilot studies with
sample sizes of 12 and 31 [64,68], a small one group
study of 25 women [67] and two larger RCTs [65,69].
Category 2 evidence was present for anxiety related to
surgery, although this was compared to sham only[69].
Fairly good evidence existed for agitation in dementia
compared to control, although generalisability was lim-
ited by small sample size, lack of control and high attri-
tion[65]. Evidence for reducing stress, anxiety and heart
rate and thus enhancing spontaneous labour is promis-
ing, but limited by lack of control and a small, volunteer
sample [67].
Chronic respiratory conditions
Six studies on respiratory conditions were identified,
chronic obstructive pulmonary disease (COPD)[70-73],
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chronic obstructive asthma [74] and bronchiectasis [75].
Overall, the evidence is Category 2, as studies were well
designed but had a number of methodological flaws.
Study designs included two controlled trials using ran-
domised blocking design, matching groups for demo-
graphic and clinical factors [71,72]; one crossover design
[70]; two pilot RCTs [74,75] and an RCT [73]. Results
showed improvements in dyspnoea and decathexis com-
pared to sham, although limited by high attrition, poor
blinding and a small sample [70]. The pilot studies (with
thesameauthors)showedimprovedqualityoflifefor
asthma patients [74] and sputum and respiratory scores
for bronchiectasis compared to control [75], but are lim-
ited by small sample sizes, high dropout and lack of
blinding. The matched studies [71,72] provided high
quality evidence for improvements in dyspnoea and
related outcomes, with valid and reliable interventions
and outcome measures, and blocking design giving
more powerful treatment effects for small samples.
Anaesthesia/consciousness
Three studies investigated the effects of acupressure on
levels of anaesthesia or consciousness. These levels include
the acoustic evoked potential (AEP), changes in which
reflect the depth of anaesthesia and transition from awake
to anaesthetised [76]; bispectral index (BIS) and spectral
edge frequency (SEF) which are measures of the level of
consciousness during anaesthesia/sedation [77,78]. Over-
all, the evidence is Category 3 as only three studies were
identified, all had repeated measures designs and small
sample sizes (between 15 and 25), although one was pow-
ered [68,76-78]. Patients acting as their own controls in
these studies can cause practice and carryover effects,
although reduced by counterbalancing/randomising of
treatment order. However, lack of control group and lack
of details on sample selection limit the evidence.
Stroke
Three studies investigated acupressure for stroke
[79-81]. All three were RCTs; Shin and Lee [80] used a
blocked randomised design comparing acupressure to
acupressure plus aromatherapy, Kang et al [81] rando-
mised to acupressure or control groups; McFadden and
Hernandez [79] used a crossover design comparing acu-
pressure to control. Although studies used good designs
and results suggested significant improvements in pain
[80], motor power [80], limb function [81], daily living
[81], depression [81], and heart rate [79], all findings
were limited by small unpowered samples and poor
reporting, so evidence is rated at Category 2.
Body weight
Two randomised studies investigated the effect of acu-
pressure on body weight, although for very different
conditions - weight loss [82] and weight gain in prema-
ture babies[83]. Elder et al’s [82] RCT compared ‘Tapas
Acupressure Technique’
®
(TAT)
1
, qi gong and control
(self directed support). TAT resulted in greater weight
loss than both qi gong and control. Chen et al’s[83] RCT
compared acupressure and meridian massage to routine
care, resulting in significantly more weight gain. The
weight-loss study was high quality with a large sample,
design-adaptive group allocation (equivalent to randomi-
sation, but balanced for demographic and clinical fac-
tors). The weight gain study was randomised and
matched for weight and gestation age and used blinding
(although details are not clear), but had a small sample
size and lack of information on randomisation, allocation,
drop outs, harms and ethics. The evidence for weight
loss/gain is Category 2 as more studies are needed.
Visual impairment
Two non-randomised studies from China and Taiwan
evaluated acupressure for schoolchildren with visual
impairment [84,85]. Both found improvements com-
pared to control but were limited in reporting of study
design and findings and did not randomise. With only 2
studies, both with significant limitations, the evidence
for acupressure for improving eyesight is Category 3.
Other conditions
The remaining 11 articles on acupressure investigated
distinct health conditions which could not be grouped.
A systematic review evaluated the effect of acupoint
stimulation for side effects of breast cancer treatment
[47]. 26 studies were identified, concluding that evidence
is high quality for nausea and vomiting but weak for all
other adverse effects. It was well conducted with appro-
priate inclusion criteria, Jadad scale for rating and two
independent raters.
Ballegaard et al [86,87] studied acupressure for angina.
The 1999 study [86] was a cost benefit analysis and used
non-equivalent control groups, a volunteer and conveni-
ence sample and used co-interventions of acupuncture
and the self-care program. The 2004 study [87] had a
good sample size although subjects were not randomised,
the follow-up period was long, but no equivalent control
group or blinding. Again, it was difficult to isolate the
effects of acupressure from co-interventions. At baseline
the sample did not significantly differ to Scandinavian
heart patients. This ‘quality control review’, is subject to
selection, expectation and social biases.
Gastrointestinal motility was studied by Chen et al
[88,89], with significant improvements demonstrated. In
[88], although the intervention was well reported, rando-
misation is not described (although groups were homo-
genous for a range of variables). In [89] the sample was
small and not powered and the study was single-blind,
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although groups were homogenous. Significant effects
were observed.
A poorly reported study observed that acupressure on
PC6 significantly reduced gagging in 109 dental patients
[90]. The study was described as double-blind although
blinding procedures were not described. Details of the
sampling were not available.
In a comparison of acupressure with oxybutinin for
nocturnal enuresis in children[91], the main flaw was
the very small sample size, with no details of sampling,
comparison of groups or randomisation, potential selec-
tion bias and no placebo/sham group.
A controlled trial of acupressure for 30 patients with
peripheral arterial occlusive diseases (PAOD) reported a
significant reduction in transcutaneous oximetry[92].
This is a poor quality study with an apparent lack of
randomisation and non-equivalent control group, poor
reporting and no comparison of groups, although out-
comes are objective and intervention is well reported.
A high quality RCT of acupressure for symptoms of
diabetes found improvement in Hyperlipidemia, hyper-
trophy and kidney function [93] Acupressure was given
regularly for 3 years, an unusually long follow up period
and showed improvements in hyperlipidemia, ventricular
hypertrophy, kidney function and neuropathy. The sam-
ple size was appropriate (although fairly high attrition)
and group allocation was random. Very good description
of treatment was provided (14 STRICTA items
reported) although discussion is limited.
Yao et al [94] conducted a single group study of mas-
sage combined with acupressure for 85 patients with
chronic fatigue syndrome. Treatment was effective in
91.8% of cases. This study did not use any clear out-
come measures, had no control, and only reported 7
STRICTA items, and given its poor reporting it is low
quality.
An uncontrolled pilot study was conducted of vaginal
acupressure for sexual problems[95]. This showed signif-
icant improvements in symptoms, physical health, men-
tal health, sexual ability and quality of life. This study is
severely limited by small sample, lack of control, no
details of recruitment, unvalidated and subjective out-
come measures and poor reporting of acupressure. In
addition the intervention did not appear to be based on
meridian theory.
Sugiura et al [96] conducted an uncontrolled study
with 22 healthy volunteers of the effects of acupressure
on yu-sen, souk-shin and shitsu-min on heart rate and
brain activity. Heart rates decreased. This study investi-
gated mechanisms rather than effectiveness.
Analysis/Summary of quality
Twenty-two of the 80 included studies were graded C
(the lowest quality grading). All five of the studies in
Chinese language were graded C (or ungraded), and
most of the Shiatsu studies were graded C. Analysis of
results over time suggests some improvement in the evi-
dence base. Figure 2 shows an improvement in the aver-
age number of STRICTA items reported by studies,
shown by the line of best fit. Figure 3 indicates a reduc-
tion in the percentage of C graded papers over time,
and an increase in those graded B. Figure 4 shows the
numbers of studies and numbers of studies for each A/
B/C grading for the different countries. This shows no
obvious trend, although countries publishing more stu-
dies (Taiwan, USA and Korea) seem to have better qual-
ity studies, compared to countries with only one or two
publications. Regarding quality appraisal, in a third of
papers, a third reviewer was need to reach agreement
on quality grading.
Discussion
Summary of evidence
These findings provide an important addition to the
existing knowledge base on Shiatsu but are very limited
in providing any evidence of efficacy for Shiatsu. To our
knowledge this is the first systematic literature review
for shiatsu.
The strongest evidence for acupressure was for pain,
post-operative nausea and vomiting, and sleep.
Study design & quality
While much of the research is of insufficient quality to
provide consensus on Shiatsu or acupressure use, some
high quality clinical research (particularly around pain)
does exist. The methodological limitations of the studies
reported in this systematic literature review included
small sample sizes, non-reporting of follow up, insuffi-
cient details on sampling, high drop-out rates, uncon-
trolled design and lack of blinding. Many studies were
also underpowered.
Although most studies were RCTs, many studies used a
controlled design but controls were non-randomised (8),
Figure 2 STRICTA scores over time.
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crossover (5) or within-subjects (6) or they were uncon-
trolled (10), or observational (1). Lack of randomisation,
allocation concealment and comparable treatments can
create bias as non-randomised controlled trials can be
subject to confounding factors such as time-related or sea-
sonal bias. Evidence for Shiatsu is thus severely limited as
only 3 of the 9 studies used a control group, one of which
was non-random, with two pilot studies. Crossover designs
may be subject to practice effect, especially for self-admi-
nistered acupressure. Within subjects repeated measure
designs can also be subject to learning, and are only useful
for stable populations such as those with a chronic disease
or healthy volunteers (as used by studies on anxiety,
dementia and consciousness in this review). One-group
uncontrolled studies are of limited value due to a range of
potential confounding variables. Longitudinal designs such
as [7] are useful to evaluate effects of a treatment, but
again causality cannot be implied, and there is increased
risk of Hawthorne effect or conditioning. Well-conducted
randomised trials are therefore more likely to have internal
validity and thus accurately estimate the causal effects of
interventions than non-randomised studies [15]. However,
certain study designs are more appropriate for certain
interventions and populations[97] and contention is emer-
ging about how complementary medicine should be evalu-
ated[98-103]. The complexity of interventions such as
Shiatsu, including their patient-centred and individualised
nature, practitioner and non-specific effects, the influence
of patient choice, and potential synergistic effects require
innovative evaluative approaches.
Most studies used a small number of acupoints for a
specific condition or symptom in a protocol approach,
which facilitates replicability[104]. MacPherson et al
[105] identify three levels of individualisation in acu-
puncture: “explanatory”trials which use the protocol
approach; partially individualised treatments using some
fixed points plus some flexible point choice; and “prag-
matic”trials which use fully individualised treatment
unique for each patient, as used in Shiatsu/TCM treat-
ment[105]. Pragmatic trials can be highly valuable, for
example the trial of acupuncture for back pain which
informed NICE clinical guidance in the UK[106].
There was an improvement in the quality/reporting of
papersoverthetimeperiod searched. This may have
been due to a greater appreciation of research amongst
practitioners, advances in research methods in acupres-
sure/shiatsu and the recent publication of a number of
guidelines on presenting research such as the CON-
SORT, STRICTA and TREND statements used in this
review [11,12,14].
The reporting of studies was very limited for many
papers, with items most commonly missing from the
CONSORT checklist including: 1a (identification as RCT
in title); 16 (numbers of participants included in each
analysis); 6b (changes to trial outcomes); 8,9 and 10
(details of randomisation procedure); 14b (why the trial
was ended); and 23 and 24 (registration number and full
protocol access) [12]. The average of 10.09 (63%) of
applicable STRICTA items reported is similar to a pre-
vious review (53.4%) [107]. Theincreaseinthenumber
of STRICTA items reported over time is likely due to the
gradual adoption of the STRICTA guidelines published
in 2001 [11,107]. In common with this previous review
the items most commonly missing were details of practi-
tioner background, setting/context and explanations to
patients, as well as amount of pressure used (equivalent
to depth of insertion of needle), style of acupressure, de
qi or the extent treatment was varied, perhaps less rele-
vant to acupressure than acupuncture. Awareness of
STRICTA guidelines is likely to be the key factor[107].
Implications for practice
For conventional practitioners
Many of the conditions with the strongest evidence
(pain, post-operative nausea and vomiting, and sleep)
are side effects of or challenging symptoms for
Figure 3 Chart of study quality over time.
Figure 4 Country of study.
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conventional medicine suggesting that an integrated
treatment approach may be of benefit. Conventional
healthcare practitioners may therefore consider acupres-
sure, in particular: SP6 for dysmenorrhoea; PC6 for
N&V postoperatively, in chemotherapy and pregnancy;
combinations of ST36, SP6, KI1, KI3, HT17, KI11 and
GB34 for renal symptoms; a range of points for COPD;
HT7 and other points for sleep in elderly residents; and
perhaps GB20, GV20, HT7, PC6 and SP6 for agitation
in dementia. The evidence for protocol-based treatment
supports suggestions that nurses incorporate acupres-
sure and Shiatsu into their practice, in particular for
pain relief, fatigue in cancer, augmenting effects of med-
ication, providing comfort and improving breathing
[108-110]. Shiatsu could be effectively delivered in gen-
eral practice but further research in clinical and cost
effectiveness is warranted [111].
For shiatsu/CAM practitioners
While much of the research carried out with Shiatsu or
acupressure as an intervention is of insufficient quality
to inform practice, the high quality evidence for pain,
post-operative nausea and vomiting, and sleep may be
of use to Shiatsu and acupressure practitioners. These
symptoms highlight the value of acupressure/Shiatsu as
a complementary approach
to conventional treatment. The findings relating to
protocol-based acupressure may not directly inform the
evidence base for more individualised and holistic treat-
ments. However, the evidence for a specific acupoint for
a specific symptom/condition can be integrated into an
individualised treatment by combining with points sui-
ted for the individual. Hsieh et al provide pragmatic evi-
dence for individualised treatment for low back pain
and headache [31,32,40]. Some studies also supported
the long-term effects of acupressure/Shiatsu, for exam-
ple for headache [40], low back pain [31,32], and nausea
and vomiting [48].
This review has highlighted the contention around the
specificity of CAM treatments. Acupressure was often
effective compared to control but not sham or medica-
tion, suggesting that effects are non-specific. Examples
include labour pain [34], dysmenorrhoea [112], renal
symptoms of fatigue, depression and sleep [54-56,59]
and nausea and vomiting [8]. However, other studies
found effects compared to sham treatment for similar
conditions [8,35-37,47,62], and patient’s belief in treat-
ment may not affect results [63], suggesting specific
effects. This review therefore provides little clarity on
specificity of effects.
Shiatsu is an inherently safe treatment [113]. Four sin-
gle case reports of adverse events occurring following
Shiatsu massage were identified (not included in review)
[114-117] as this review focussed on efficacy rather than
safety these findings were incidental and there are likely
to be more reports on safety. This is an important area
for the profession regarding safety issues and possible
causal links between Shiatsu and adverse events. Profes-
sional bodies for Shiatsu may need to consider the
development and piloting of an adverse event reporting
system for Shiatsu. Work by Andrew Long provides a
useful typology of adverse effects [118]. These are: Type
1: Responses unconnected to the CAM modality; Type
2: Transitional effect (client-perceived and theory-con-
sistent); Type 3: Transitional effect (theory and experi-
entially consistent); Type 4: Undesired, but not unsafe
event or effect; Type 5: Potentially adverse event or
effect and possible risk to client safety. This typology
could be utilised in future studies.
Implications for research
The research base for Shiatsu is still very much in its
infancy and the profession will need to work closely
with practitioners and researchers in order to build up a
larger body of evidence. Given the prevalence of Shiatsu
used in the UK (820 registered practitioners/teachers/
trainee teachers
2
), the need for high quality research is
imperative. Shiatsu practitioners should be encouraged
to engage in research using well designed and reported
studies, in particular with large samples and controlled
designs.
Results have highlighted that alternative RCT designs
may be necessary, such as:
•Whole systems research, which includes qualitative
and quantitative methods to include the broader
aspects of treatment, not just the intervention
[119,120]
•Mixed-methods research, as qualitative data can
provide additional information on patients’and/or
practitioners’views on the effectiveness of treatment.
Many studies are including such qualitative data as
part of their design to provide a broader picture of
patient outcomes [119].
•Preference trials, which include patient choice of
treatment, often important in CAM, producing more
generalisable results, such as in the study by Lucini
[20],
•Early phase research or pilot studies to generate
hypotheses, identify the most appropriate health
conditions, patient groups and treatments to test in
full clinical studies[121], given the limited evidence
base for Shiatsu.
•A pragmatic design as used by some studies in this
review. Pragmatic trial design overcomes some of
the barriers of conducting RCTs in CAM, including
improved recruitment and providing patient-centred
treatment as usual. Only six studies used a prag-
matic design; three for shiatsu [7,19,86] and three
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for acupressure [31,32,87]. Examples of pragmatic
trials are the cohort multiple randomised controlled
trial [122] and health services research [101]. There
is promising research using both a pragmatic
approach to evaluate Shiatsu as part of an integrated
or massage intervention [19,21,123]. A flexible pro-
tocol approach could be used to improve replicabil-
ity[104].
•One of the main issues in RCTs of complementary
approaches is the control treatment, for example the
limitations of blinding and sham acupressure. The
included studies have confirmed that “sham”acu-
pressure including light touch at acupoints does
have an effect. The highest quality evidence was
from three armed trials which use sham treatment
and an inert control, as advocated in acupuncture
research[124]. Shiatsu (as distinct from acupressure)
presentsfurthercomplexitiesastreatmentsare
based on Hara diagnosis and rarely if ever “standar-
dised”. This needs to be adequately reported in
papers, following guidelines such as CONSORT or
TREND.
Although excluded from this review due to resource
constraints, qualitative studies provide additional infor-
mation on patients’and/or practitioners’views on the
effectiveness of treatment [125-127]. Many studies now
include such qualitative data as part of their design to
provide a broader picture of patient outcomes.
Particular areas to focus research, commonly treated
with Shiatsu/acupressure include psychological and
musculoskeletal conditions, in particular neck/shoulder,
lower back problems, arthritis, depression, stress and
anxiety[6]. There is also good evidence for sleep and
symptoms of renal disease, but studies to increase the
generalisability of these findings is necessary.
Taiwanese researchers appear to have been most pro-
lific in this area, as well as Korea and the USA. Given
the increasing use of CAM in Europe more research
based in European countries may be needed. Given the
prevalence of Shiatsu used in the UK, the need for
research is imperative.
Use of quality guidelines such as STRICTA and CON-
SORT is advised to improve the reporting of studies,
especially details of interventions, to provide replicability
as well as to inform practice [11].
Strengths and limitations
A wide range of databases was used to maximise the
number of articles captured. This review used recog-
nised quality checklists to evaluate studies and each was
independently assessed by 2 reviewers, with fairly high
inter-rater agreement, and with a third reviewer for
adjudication.
The checklists used to calculate the quality of the
reporting of studies (CONSORT, TREND etc) were use-
ful but do have limitations. In particular with such a
broad range of study designs other than RCTs, the
appropriateness of checklists for specific study designs is
limited. For example the TREND checklist for nonran-
domised study designs may require additional specific
criteria for specific types of nonrandomised designs [14].
Searches were restricted to UK/USA databases due to
resource constraints; including Asian databases may
have added to the evidence. Language bias may also
have been present, although some Chinese language stu-
dies were included. There was no attempt to find grey
literature except searching for UK postgraduate theses;
no contact was made with individual authors due to the
large numbers of authors.
As this review was not limited by health condition, the
breadth of the included studies necessitated limiting
inclusion by excluding studies prior to 1990. This may
have created bias.
As the quality assessment in a systematic review
depends on contextual and pragmatic considerations, it
was necessary to limit the number of articles reviewed
due to time and resource constraints [97]. In particular,
purely qualitative studies were excluded, which may
have limited results given the now recognised value
given to qualitative outcome measures, particularly in
complex interventions such as Shiatsu.
Conclusions
This review identified very little Shiatsu research, sug-
gesting well designed studies are needed. The evidence
for acupressure and pain is generally consistent and
positive. There is also evidence for acupressure
improving sleep in institutionalised elderly. Acupres-
sure studies for nausea and vomiting have been some-
what inconsistent, with strongest evidence for post-
operative nausea, and may merit further research. Evi-
dence for pain, nausea and vomiting and sleep support
an integrated approach using acupressure for condi-
tions problematic to conventional medicine. There is
limited evidence for chronic respiratory conditions,
especially COPD, and psycho-social aspects of health,
anaesthesia and other health conditions. Evidence on
specific vs non-specific effects is inconclusive. This
review highlighted the challenges of conducting rigor-
ous research into CAM, which are complex, individua-
lised and patient-centred, but illustrates useful study
designs such as pragmatic/flexible protocol, 3 armed
with sham and no treatment, longitudinal and
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preference trials. Evidence appears to be improving in
quantity, quality and comprehensive reporting, but
there is still much room for improvement.
Endnotes
1. http://www.tatlife.com/
2. Personal correspondence with Shiatsu Society UK
Additional material
Additional file 1: Table 1. This table contains details of each of the
included studies
Acknowledgements
This study received funding from the Shiatsu Society, UK.
We would like to thank Julie Donaldson for her help with the literature
searching and reviewing.
Author details
1
Allied Health Sciences Department, Faculty of Health and Social Care,
London South Bank University, 103 Borough Road, London SE1 0AA, UK.
2
Institute of Basic Research in Clinical Medicine, China Academy of Chinese
Medicial Sciences 16 Dongzhimeng, Nanxiaojie, Beijing, 100700, China.
Authors’contributions
XL conducted the searches and retrieved the articles. XL and AL reviewed
the articles and NR was the adjudicator. XL and AL compiled the evidence
tables. AL and NR wrote the introduction and discussion section. AL created
the tables and graphs in the main text. All authors read and approved the
final manuscript.
Competing interests
The authors declare that they have no competing interests.
Received: 20 July 2011 Accepted: 7 October 2011
Published: 7 October 2011
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Cite this article as: Robinson et al.: The evidence for Shiatsu: a
systematic review of Shiatsu and acupressure. BMC Complementary and
Alternative Medicine 2011 11:88.
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