Randomised trials relevant to people with schizophrenia:

a survey of studies published in Chinese literature - II S Baier,1 C Koenig,1 C Pfeiffer,1 P von Reibnitz,1 A Chakrabarti,2 W Wong,2 CE Adams2

1University of Ulm, Schule fuer Medizinische Dokumentation, Ulm, Germany 2Cochrane Schizophrenia Group,University of Leeds, Leeds, UK

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Background As described in Part 1, Chinese evaluative studies are not widely disseminated in bibliographic databases commonly used in the rest of the world. China Academic Journals1 (CAJ) indexes 900 Chinese biomedical journals many of which may be relevant for schizophrenia and has full-text PDF files for all articles.

Aim • To investigate whether using Traditional Chinese language terms for randomised trials (RCTs) and schizo- phrenia results in more comprehensive retrieval of relevant articles than using English phrases alone. • To produce a simple profile of the content of randomised trials in Chinese literature relevant to the care of people with schizophrenia.

Methods • Search strategy 1. In July 2005 we updated the previous English language search (see Poster 1) using phrases: ((schizophrenia or psychosis or psychotic or antipsychotic or extrapyramidal or “chronic schizophrenia”) and (randomly or randomization or randomised or randomized or “double blind” or “double blinded”)) in the field “keywords”, which covers the fields “title” and “abstract”.

2. We searched CAJ 1994-July 2005 using Chinese phrases: ((精神分裂症 or 精神病 or 精神病 or 抗精神病的 or 椎体外系 or 慢性精神分裂症) and (随机 or 随机选择 or 双盲)). • Management of data We downloaded records, manually scanned for RCTs, acquired full text PDFs for possible randomised trials, selected only RCTs for relevant data extraction, and added these data to a MS Access database.

Results

1. http://online.eastview.com/cnki_login/index.jsp Contact details: Clive E Adams e-mail:ceadams@cochrane-sz.org

Most common interventions: medications Number of RCTs by year Average number of people in these RCTs by year

In a matter of only 10 years the Peoples Republic of China has become one of the most prolific countries producing RCTs relevant to schizophrenia. The average is now approximately 200 trials per year; 20 - 30% of the world’s studies in the last four years. By using Chinese phrases 30% more studies were found in CAJ compared with using English alone. The studies found solely by using Chinese phrases seem similar to those identified by using English in terms of size, interventions and outcomes – these are studies of relevance to the care of people the world over.

Limitations We still do not know whether the contents of CAJ includes all schizophrenia trials from China. CAJ’s search engine is very limited, there are probably even more relevant studies that we failed to identify.

Conclusions

• For those wanting comprehensive identification of trials in CAJ, also Chinese phrases should be used. • Systematic reviews which do not include searches of CAJ may not be comprehensive. • The Cochrane Schizophrenia Group welcomes all new reviewers, especially those who can read Mandarin!

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1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004

English search Chinese search

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1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004

Chinese search English search Total

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Chlorpromazine Clozapine Haloperidol Quetiapine Risperidone

Chinese search English search Total

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BPRS PANSS SANS SAPS SDSS TESS

Chinese search English search Total

Most common outcomes: scales

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2001 2002 2003 2004

Chinese

World wide

23 %

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32 % 33 %