To review the use of acupressure and to identify any effects, including side-effects, that are supported by evidence.

The author used the Research Council for Complementary Medicine database (CISCOM) covering the period 1986-1995 and also searched the references of retrieved articles for additional relevant studies. The search was limited to English language publications.

Study designs of evaluations included in the review

Clinical trials with control groups, clinical trials without control groups, case study series, and single-case experimental design. Three trials were of cross-over design.

Specific interventions included in the review

Treatment groups received the prophylactic use of single-point acupressure (e.g. using pericardium 6 (PC6) as an antiemetic treatment), or the restorative use of multi-point acupressure (e.g. using auriculotherapy in multi-point treatments). Control groups received placebo, wrist acupressure devices, oral diazepam, relaxation (tapes), standardised Chinese medical preparations, and an unstated medication.

Participants included in the review

Participants in the PC6 studies were experiencing nausea and vomiting: in pregnancy; postoperatively; in chemotherapy, motion sickness and terminal illness. Other participants were being treated with auriculotherapy for obesity, anxiety control, cholelithiasis, hypertension, pain and urinary calculus.

Outcomes assessed in the review

Reductions of nausea and vomiting, weight, pain, palmar sweating or pulse rate.

How were decisions on the relevance of primary studies made?

The author does not state how the papers were selected for the review, or how many of the reviewers performed the selection.

The methodology of all of the studies reviewed was assessed for randomisation procedure, type of control and blinding, and reliability and validity of outcome measures. The author does not state how the papers were assessed for validity, or how many of the reviewers performed the validity assessment.

The author does not state how the data were extracted for the review, or how many of the reviewers performed the data extraction.

How were the studies combined?

The studies on PC6 were listed in a table, grouped by condition, and the results summarised in a narrative review. The remaining studies for auriculotherapy were presented in a narrative discussion of study characteristics and outcome measures where available.

How were differences between studies investigated?

The author does not state how differences between the studies were investigated.

Twelve clinical trials with data reported for 904 participants (participant completion ranged from 56-100%) with 495 participants in the pregnancy studies, 316 in the postoperative studies, 39 in the chemotherapy studies, and 54 in the motion sickness studies. One further single-subject experimental design study is described for nausea and vomiting with 6 participants in a hospice setting.

Seven studies (2 RCTs, and 5 case study series) with 2,466 participants were included for the review of multi-point auriculotherapy.

The most convincing finding supporting the effectiveness of acupressure comes from methodologically rigorous studies of the use of PC6 as an antiemetic. A number of studies have shown that PC6 is more effective than a placebo in reducing feelings of nausea during pregnancy, after surgery, and in cancer chemotherapy. There is no convincing evidence that PC6 acupressure reduces the incidence of vomiting. Results for 7 studies on auriculotherapy found no significant difference between treatments in 5 of the studies and results of interest in favour of auriculotherapy in 2 further studies were weak because of flaws in the study designs.

No serious side-effects were reported in any of the studies reviewed.

The scientific quality of most of the published studies examining the effectiveness of multipoint acupressure, predominantly auriculotherapy, has been poor, without adequate control groups, randomisation, placebos, blinding and statistical analyses. There seems to be a cultural divide between theory and methodological rigour. The scientifically rigorous studies have tended to be atheoretical in selecting the acupoint for treatment and in explaining how the point may work.

The author has stated the research question but no inclusion or exclusion criteria for the review. The literature search is poor because the author has searched only one database, does not report the keywords used, and has restricted the search to English language publications. Given the content of the research, it is possible that non-English studies and unpublished relevant studies may have been missed.

The author has not reported on how the articles were selected or how many reviewers selected the articles and extracted the data. The quality assessment procedure is described but is not rigorous. The studies are not statistically combined and there is no discussion or test for homogeneity. The author mentions several methodological drawbacks for the included studies and the differences imprecise use of the treatments through not assessing conditions according to Chinese methodology. There was insufficient data reported from the individual studies or about the included studies so the author's conclusions should be viewed with caution.

Practice: The author does not state any implications for practice.

Research: The author states that further research is needed to prove the usefulness of acupressure in treating nausea using validated 'quality of life' type measures. Reliable measures that clearly distinguish between the feelings of nausea and actual vomiting are also necessary.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.