A Study On Quality Evaluation System Of Medical Journals

Background and objectives:The level of academic journals in a certain period of time is determined by the quality of papers published in the journal, so the level of an academic journal can be indirectly reflected by evaluating its overall papers. The most reliable approach to evaluate the quality of a journal is to appraise papers of different fields by different groups of professors respectively, and this can not be completely replaced by any other method. However, it is not practical to evaluate a journal by appraising all papers, because it costs too much and is also difficult to implement. Thus, how to setup a comprehensive evaluation system of academic journals is a difficult problem.In recent years, the "core journals" concept was introduced into many research institutions and universities; it has become a scale on journal evaluation. In 1934, "Core journals" theory was first proposed by S.C.Bradford, who was a well-known British philologist. His "laws of concentration and dispersion in literature" revealed an important feature in papers distribution of the Journal: In a certain academy or professional, the majority of information is contained in a small number of journals, while a big amount of journals contain only a small percent of information. In other words, the papers are highly concentrated in a small number of journals, and this is called "core journals" effect. As the result, different "core journals" appeared in different scientific and technical fields.Journal Impact Factor plays an important role in the journals evaluation. Actually, it reflects the average cited rate of the papers published in a journal. Citation includes self-reference cite and others" cite. Since the number of self-reference cite has little to do with influence, Impact Factor does not make a distinction between them. This is the limitation of using Impact Factor to evaluate the scientific and technical journals.In 2005 , Jorge E. Hirsch who is a physicist of the University of California, San Diego, proposed a new way of evaluation about a individual's achievement—H-index. When a scientist who has published at least H papers, and each of these papers has been cited for at lease H times, the H-index of this scientist is H. Then, Broughton used this way for journals evaluation. It defined as: One journal at most has h papers, each of them must have been cited h times at least, h is the natural number of this journal. Currently, H-index is widely used in the evaluation of scientific and technical journals.Evaluating journals of science and technology is an extremely complex and important job. Not only does it reflect the level of journals, but also reflect a country's development level of science and technology. The purpose of this study is: 1. Discuss the advantages and defects of commonly used journal evaluation indicators and methods in domestic and overseas. 2. Discuss the function of h index in the medical journals evaluation. 3. To reduce the disadvantages of Influence Factor and h index, establish a new indicator: A-index. 4. Research A-index's evaluation effect. Make Pearson Correlation analysis between principle component analysis result and different journal evaluation indices, include A-index.Materials and methods:As statistical material, we selected top 44 medical journals in h-index from citation data which published by CNKI in May 6, 2008 , then we collected other different indicators, such as Impact Factor, of these 44 kinds of medical journals from 2006 CHINESE JOURNAL CITATION REPORTS and 2007 CHINESE JOURNAL CITATION REPORTS.Established formula (?) , using this formula to calculate the A index ofthe 44 kinds of medical journals. Using SPSS 17.0 Statistical analysis software, make a comprehensive evaluation by principal factor analysis on 44 medical journals. With Spearson correlation analysis, we compare the evaluation effects of A index,h indexand the other traditional indices.Results:1. A-index has better evaluation ability on journals than h-index, impact factor and other indices. From the analysis result of the 44 medical journals, we found that the correlation between principle factor analysis result and these indices are 94.7%, 92.4%, 68.4%, 68.2%.2. Easily calculate. The formula is very simple as: (?).3. There is a highly correlation between A-index value and the comprehensive evaluation value, which was analyzed from 13 commonly used international journal indices. From the result on 44 medical journals above in text, they have a correlation of 94.7%.4. H-index will increase with the time. Therefore, over time, the more papers in volume of periodicals, the higher H-index will be. But A-index reduced this kind of effect.5. By publishing a large number of low-quality self-citation articles, journal can increase h-index, impact factor and citation frequency, but decrease A-index value. A -index can effectively discharge artificially factors to raise the self-citation index, impact factor and h-index.Conclusions:Quality evaluation system of Journals was first appeared in 1970s. With the development of science and technology, old journal evaluation system, especially on medical journals couldn't suit them well. To ensure medical journals developing in a healthy way, we should create a new evaluation system on medical journal. A-index was thus derived to make up the disadvantage of classic evaluation indicators, like h-index, IF. By publishing a large number of low-quality self-citation articles, journal can increase h-index, impact factor and citation frequency, but decrease A-index value. A -index can effectively discharge artificially factors to raise the self-citation index, impact factor and h-index. As a conclusion, A-index has good prospects in journal evaluation, evaluating with a-index is a more objective and scientific way in journal evaluation.