Objective: To determine whether clinical trials originating in certain countries always have positive results.

Study Selection: Two separate studies were conducted. The first included trials in which the clinical outcome of a group of subjects receiving acupuncture was compared to that of a group receiving placebo, no treatment, or a non-acupuncture intervention.

In the second study, randomized or controlled trials of interventions other than acupuncture that were published in China, Japan, Russia/USSR, or Taiwan were compared to those published in England.

Data Extraction: Blinded reviewers determined inclusion and outcome and separately classified each trial by country of origin.

Data Synthesis: In the study of acupuncture trials, 252 of 1,085 abstracts met the inclusion criteria. Research conducted in certain countries was uniformly favorable to acupuncture; all trials originating in China, Japan, Hong Kong, and Taiwan were positive, as were 39⁄1 of those published in Russia/USSR.

In studies that examined interventions other than acupuncture, 405 of 1,100 abstracts met the inclusion criteria. Of trials published in England, 75% gave the test treatment as superior to control. The results for China, Japan, Russia/USSR, and Taiwan were 99%, 89%, 97%, and 95%, respectively. No trial published in China or Russia/USSR found a test treatment to be ineffective.

Conclusion: Some countries publish unusually high proportions of positive results. Publication bias is a possible explanation. Researchers undertaking systematic reviews should consider carefully how to manage data from these countries.

[Keywords: randomized controlled trial, publishing, China, Russia, Taiwan, Japan, acupuncture, MEDLINE, meta-analysis, periodicals]

**Table 1**: Results of Controlled Clinical Trials of Acupuncture by Country of Research.
Country	Total Trials Analyzed	Number Favoring Test Treatment	Percentage Favoring Test Treatment
USA	47	25	53%
China	36	36	100%
Sweden	27	16	59%
UK	20	12	60%
Denmark	16	8	50%
Germany	16	10	63%
Canada	11	3	27%
Russia/USSR	11	10	91%
Austria	9	8	89%
Italy	9	8	89%
Australia	6	1	17%
France	6	5	83%
Taiwan	6	6	100%
Japan	5	5	100%
Finland	4	2	50%
Hong Kong	3	3	100%
Netherlands	3	1	33%
New Zealand	3	2	67%
Poland	3	2	67%
Switzerland	3	1	33%
Bulgaria	2	2	100%
Brazil	1	1	100%
Croatia	1	1	100%
Israel	1	1	100%
Nigeria	1	1	100%
Sri Lanka	1	0	0%
Vietnam	1	1	100%
[Total]	252	171	68%

**Table 2**: Results of Controlled Clinical Trials of Interventions Other Than Acupuncture by Country.
Country of Publication	Abstracts Screened	Abstracts Included	Number Favoring Test Treatment	Percentage Favoring Test Treatment
China	196	109	108	99%
England	329	107	80	75%
Japan	317	120	107	89%
Russia/USSR	180	29	28	97%
Taiwan	78	40	38	95%
[Total]	1,100	405	361	89%

**Table 3**: Results Combining Randomized Trials from Both Studies.
Country of Publication	Abstracts Included	Number Favoring Test Treatment	Percentage Favoring Test Treatment
China	121	120	99%
England	118	88	75%
Japan	120	107	89%
Russia/USSR	29	28	97%
Taiwan	45	43	96%
[Total]	433	386	89%