There is a paucity of studies that compare the differences in published articles submitted from the East and the West in the area of neurogastroenterology and motility (NM). To compare the article topics from the East and the West which have been published, 5 Western (
The area of neurogastroenterology and motility (NM) includes studies of the brain, the gut, and their interactions that are associated with the understanding and management of gastrointestinal (GI) motility and the related functional GI disorders (FGIDs). FGID is defined as several variable combinations of chronic or recurrent GI symptoms with no definitely identified underlying pathophysiology.1 FGID is one of the most common medical conditions and its chronic symptoms markedly reduce the quality of life,2 and it reflects a variety of underlying pathophysiological abnormalities.3 The prevalence of functional dyspepsia (FD) and irritable bowel syndrome (IBS), which are representative forms of FGIDs, varies considerably among populations, and ethnicity, dietary factors, and socioeconomic conditions affect the variability.4?7 Therefore, the interest or methods for approaching these disorders may be different between Eastern and Western researchers.
Many researchers from the East and the West perform studies and publish many papers in the clinical and basic pathophysiological fields of NM. Thus, most GI journals regard the field of NM as one of the important subjects. Despite great interest in the field of NM, there is a paucity of studies regarding the difference in articles submitted from the East and the West in the area of NM. In this review, the article topics which have been published in the Eastern and the Western GI journals as well as those of authors from the East and the West in the field of NM were investigated.
Five Western and 3 Eastern GI journals were selected based on the impact factor (IF). Five Western GI journals consisted of 3 major GI journals (
Three Eastern GI journals included 2 GI journals;
Literature searches were performed via each journal’s web site. Each article’s title and abstract (full-text if needed) of the 8 selected journals were carefully reviewed by 17 GI fellows at Seoul National University Bundang Hospital. Among the review articles, original articles, and meta-analyses published from 2013 to 2014, those in the field of NM were included, while editorials and case reports were excluded. In case of JNM, a quarterly journal, the articles published during the recent 5 years (2010?2014) were analyzed.
Topics of NM were classified by prof. G.H.K into 12 categories with 60 subcategories as shown in Figure 1. Each article was classified into 60 subcategories and then re-classified into one of the 12 categories. In the next step, the article was grouped into the East and the West according to the corresponding author’s country. “Eastern country” included Asian countries including the Middle East. The US, Europe, and Australia were grouped as “Western country,” mainly based on culture and diet.
A total of 2656 articles were retrieved in our searches, of which, 842 articles (260 from the East and 582 from the West) were found to be focused on NM. The proportion of articles on NM in the 8 selected journals during the search period was 13.4% in GE, 6.1% in GUT, 11.9% in AJG, 100% in NGM, 23.5% in AJP-GI, 12.3% in JGE, 9.3% in JGH, and 100% in JNM, respectively (Table 1). When the articles on NM were analyzed in terms of the corresponding author’s country, the number of articles from the East and the West were 2 (3.3%) and 59 (96.7%), respectively in GE, 0 and 21 (100%) in GUT, 4 (11.1%) and 32 (88.9%) in AJG, 42 (12.7%) and 288 (87.3%) in NGM, 10 (9.9%) and 91 (90.1%) in AJP-GI, 22 (61.1%) and 14 (38.9%) in JGE, 30 (81.1%) and 7 (18.9%) in JGH, and 150 (68.2%) and 70 (31.8%) in JNM (Fig. 2). The Eastern countries that published articles on NM in the 8 journals included Korea (94, 37%), Japan (65, 25%), China (40, 16%), Taiwan (17, 7%), India (16, 6%), and others (Thailand, Iran, Malaysia, Hong Kong, Sri Lanka, Singapore, and Turkey) (Fig. 3).
In the next step, we analyzed the main research topics from each journal and they were categorized depending on corresponding authors.
The 5 research topics for the Eastern corresponding authors were gastroesophageal reflux disease (GERD; 58, 22.3%), FD (49, 18.8%), IBS (40, 15.4%), motility test (26, 10.0%), and visceral hypersensitivity (24, 9.2%). On the other hand, the 5 main research topics for the Western corresponding authors were brain-gut interaction (107, 18.4%), visceral hypersensitivity (105, 18.0%), IBS (94, 16.2%), FD (64, 11.0%), and GERD (59, 10.1%) (Fig. 4).
In GE, a total of 61 articles on NM were published in 2013?2014; 36 were from the US, 5 from the UK, from Germany, 2 from China and 2 from Iran. Main research fields of interest were IBS (26.2%), brain-gut interaction (21.3%), functional esophageal disorders (16.4%), GERD (13.1%), and visceral hypersensitivity (9.8%). In GUT, a total of 21 articles on NM were published in 2013?2014; 8 were from Belgium, 3 from the US, and 3 from the UK. The major research topics were categorized as brain-gut interaction (28.6%), IBS (23.8%), and visceral hypersensitivity (23.8%). In AJG, a total of 36 articles on NM were published in 2013?2014; 17 articles were from the US, 3 from Australia, 2 from China, and 2 from Japan. Main research topics were categorized as IBS (55.6%), FD (16.7%) and functional bowel disorders (13.9%).
In JGE, a total of 36 articles on NM were published in 2013?2014; 18 were from Japan, 5 from the US, and 3 from Spain. Main research topics were categorized as GERD (19.4%), FD (13.9%), functional esophageal disorders (13.9%), brain-gut interaction (13.9%), and visceral hypersensitivity (11.1%). In JGH, a total of 37 articles on NM were published in 2013?2014; 7 articles were from China, Korea, and Australia each. Main research topics were categorized as GERD (45.9%), FD (13.5%), IBS (10.8%), and motility test (10.8%) (Table 2).
In AJP-GI, a total of 101 articles on NM were published in 2013?2014. Most of the articles were from the US (55, 54.5%), while 5 were from China, 5 from Japan, and 1 from Korea. Main research topics were categorized as visceral hypersensitivity (32.7%) and brain-gut interaction (20.8%) (Table 2).
In NGM, a total of 330 articles on NM were published in 2013?2014. Large number of articles were from the US (96, 29.1%), while 15 were from China, 13 from Japan, and 7 were from Korea. Main research topics were categorized as brain-gut interaction (20.9 %), visceral hypersensitivity (18.5 %), and FD (13.6%). In JNM, a total 220 articles on NM were published from 2010?2014; 79 were from Korea, 38 from the US, 21 from Japan, and 12 from India. Main research topics were categorized as IBS (21.8%), GERD (20.9%), and FD (18.2%) (Table 2).
Many sociocultural factors, such as gender, age, economic state, education level, food, race, stress, or climate and drugs, affect the expression and course of FGIDs.3,8 It is likely that the research topic could be related to the disease prevalence. The pooled prevalence of IBS is 11.2% (95% confidence interval [CI], 9.8?12.8) in Northern Europe, 15.0% (95% CI, 11.0?20.0) in Southern Europe, 11.8% (95% CI, 7.4?17.2) in North America, and 14.0% (95% CI, 13.0?15.0) in Australia.5 However, the prevalence of IBS is relatively low in many Asian studies (< 10.0%),5,8 although Chang et al8 recently reported that the current prevalence of IBS in Asia is similar to that of the Western countries. These differences may force Western researchers to pay more attention to prevalent diseases such IBS. In addition, Western researchers tend to perform basic researches such as brain-gut interaction and visceral hypersensitivity in the field of NM compared to Eastern researchers. The differences in ways of thinking between the East and West may also affect the research fields.
In contrast, GERD and FD are the areas of great interest in the East.9 GERD has a higher prevalence in the West than in the East.10 Several factors such as differences in ethnicity and the prevalence of obesity are associated with the prevalence of GERD.9 Recent population-based studies showed that the prevalence of GERD has been increasing in Eastern Asia.11?14 The increase of GERD prevalence in Asia seems to be associated with epidemiological changes such as rapid economic growth, changes in eating habits, decreasing prevalence of
Another cause of the difference in the research area of NM between the East and the West was that the proportion of basic research articles was higher in Western journals. For example, basic research articles, such as animal or cell studies, accounted for 27.9% of the studies in GE and for 23.8% of the studies in GUT versus 19.4% of the studies in JGE. The proportion of basic research articles in NGM was 38.8%, which was higher than that of JNM (29.1%). Since studies about pathophysiological mechanism of FGIDs usually require significant experience, team approach, and adequate funding compared to general clinical studies; it is very difficult to publish a good paper in a high impact journal. This could be one of the reasons why studies about visceral hypersensitivity and brain-gut interaction have been published more often in Western journal with high IF. Many researchers from Eastern countries have difficulty in performing basic pathophysiological studies because of few experts in this field, less fund, technical limitations, clinical overburden on medical doctors, and so on. Due to these reasons, Eastern researcher tends to concentrate on clinical studies such as those on GERD, FD, and IBS, which requires relatively less time until publication than basic research. Long history and popularity of Western journals are another reasons for this difference, considering the short history of JNM. In spite of a comprehensive review of more than 2500 articles using well-established categories, a 2-year review might not clearly discern the differences between the East and the West.
JNM has played an important role in the publication of the Eastern articles on NM so far. The main aim of JNM is to provide world researchers with a technique of publishing their research results in the field of NM. Prior to JNM, NGM was the only international journal in this field. One of the most distinguished characteristics of JNM is that it has become a common official journal of many Asian societies. Therefore, JNM has become available to a very large global pool of researches and readers, especially in Asia.26 In the future, the topics of JNM will change if more Western researchers submit their studies to JNM and the ability of Asian countries to perform research increases. This could happen in the near future.
Even though our analysis for differences in research topics between the East and the West in journals related to the field of NM is limited to the last 2 years, the fields of interest in Eastern GI journals were GERD and FD, whereas those in Western journals were brain-gut interaction and visceral hypersensitivity. A few Eastern studies were found to be published in the Western GI journals with high IF, and Eastern GI journals included many articles from Eastern countries. From the analysis of the recent publication trend in the field of NM in 8 major GI journals, we were able to obtain valuable information about the differences in the research field interest between the Eastern and the Western researchers as well as between journals. The difference in interest between the Eastern and the Western journals is not just due to the journal itself, but it also depends on the author’s affiliation and their background which enables them to perform high quality research in the area of the pathophysiology of NM. These data provide evidence for the research trend and give valuable information to the researchers for determining subjects for the study and for selecting proper journals for publishing their studies.