Global trends in acupuncture research: A scientometric analysis from 1980 to 2023

Abstract

The objective of this study was to examine articles on acupuncture from past to present, revealing prevalent research trends, showcasing global productivity, identifying international collaborations, and highlighting influential publications and journals in the field. We acquired a comprehensive dataset comprising 9340 articles pertaining to acupuncture that were published within the time frame spanning from 1980 to 2023. These articles were sourced from the Web of Science and underwent rigorous analysis through a diverse set of bibliometric techniques. Our analytical approaches encompassed trend keyword analysis, thematic evolution analysis, conceptual structure analysis, factor analysis, citation and co-citation analyses, as well as an exploration of international collaboration patterns. The 3 most productive countries were China (n = 3357), the USA (n = 1351), and South Korea (n = 814). The 3 most productive journals were Acupuncture in Medicine (n = 440), Evidence Based Complementary and Alternative Medicine (n = 415), and Medical Acupuncture (n = 400). The 3 journals with the highest h-index on acupuncture were the Journal of Alternative and Complementary Medicine (h = 45), Pain (h = 41), and the American Journal of Chinese Medicine (h = 35). The most active author was Park Hi-Joon (n = 128). According to the findings of the factor analysis, acupuncture literature was grouped around 3 main subfactors. The primary factor encompassed topics related to the effectiveness/applicability of the treatment method for various medical conditions and general principles of acupuncture methods and points. The second factor covered topics related to mental health and quality of life. The third subfactor addressed the qualitative and quantitative analysis direction of acupuncture, such as meta-analysis and systematic reviews, and randomized controlled trials. From the past to the present, the most extensively researched main topics in acupuncture literature have covered a wide range of subjects. Prominent themes among these topics included acupuncture methods and applications, pain management, the nervous system and acupuncture, mental health and acupuncture, quality of life, and general health. In recent years, emerging trends in acupuncture research have focused on neurological health issues, oncology and cancer treatment, women’s health and hormonal issues, sleep problems, digestive issues, and studies related to the quantitative and qualitative evaluation of acupuncture research.

1. Introduction

Acupuncture is a traditional Chinese medical practice dating back thousands of years and is currently recognized as a popular therapeutic method worldwide. This practice involves the insertion of fine needles into specific areas of the body and manipulation of these areas.^[1,2] According to traditional Chinese medicine, there exists a vital energy within the body known as “qi,” and health is dependent on the free flow of this energy.^[3,4] The primary objective of acupuncture is to holistically improve the body and enhance physical, emotional, and mental well-being by regulating the flow of energy.^[5]

While acupuncture aims to restore balance to the flow of energy in the body, it can also assist in pain relief, inflammation reduction, and the treatment of various health issues. In the field of modern medicine, research on the effects and application methods of acupuncture has increased, and it is being evaluated as an integrated treatment option with traditional medicine.^[5,6] Today, acupuncture is offered as a healthcare service in many countries and is used in managing various health concerns. Despite ongoing debates about the effectiveness of acupuncture, numerous clinical studies indicate positive outcomes in the treatment of several health issues.^[1]

Though the precise workings and mechanisms of acupuncture are not yet fully understood, many individuals have reported experiencing its effectiveness in enhancing their health and well-being. Acupuncture has been reported as an effective method for alleviating or eliminating pain, particularly in conditions such as migraines, back pain, fibromyalgia, sleep disorders, and digestive problems.^[1] Acupuncture can contribute to the treatment or management of various chronic health issues.^[4,6] It can also aid in the management of stress, anxiety, depression, and other emotional concerns. Restoring the balance of energy flow within the body may also support emotional stability. Some research suggests that acupuncture may contribute to the alleviation of anxiety and depression symptoms.^[7] Furthermore, certain studies have reported that acupuncture may help alleviate symptoms of dermatological conditions such as atopic dermatitis, acne, psoriasis, and rosacea.^[8] Additionally, acupuncture is believed to have effects that expedite wound healing and can assist in reducing inflammation and the treatment of various health issues associated with inflammation.^[9]

Bibliometric analysis is a research field that systematically investigates the quantitative and qualitative aspects of scientific literature using data analytics and statistical methods.^[10,11] This analytical approach is employed for the examination and assessment of text-based sources, including academic publications, journal articles, conference papers, and other scientific documents.^[11] Bibliometric analysis serves as a crucial research method, enabling researchers to comprehend the evolution of scientific research domains, patterns in publications, citation relationships, and the overall structure of scientific communities.^[12] It offers valuable insights to researchers, scientific communities, and decision-makers, assisting them in more effectively guiding and planning the dissemination of scientific knowledge. This type of analysis plays a pivotal role in advancing scientific discoveries and research strategies.^[13]

The primary objectives of bibliometric analyses encompass the examination of publication trends, citation analyses, research network analyses, data mining, and discoveries. Publication Trends analysis involves assessing academic trends by investigating the distribution and evolution of publications over time within specific subject areas, disciplines, or research domains.^[13,14] Data Mining and Discovery analyses aim to extract scientific knowledge from extensive datasets using text mining techniques, potentially leading to the identification of new research areas. Research Network Analyses concentrate on examining the structures of scientific communities and collaborative networks among researchers, thereby identifying interdisciplinary collaborations and research networks.^[10,12] Citation Analyses focus on evaluating citation relationships between studies and measuring the academic impact of specific works, thus identifying influential contributions and key research topics.^[14]

In this study, the aim is to analyze scientific articles published on acupuncture from the past to the present in order to uncover research trends and popular trends in this field, identify collaborations between countries, and determine influential publications and journals through citation and co-citation analyses.

2. Methods

2.1. Search strategy

In order to access scientific studies related to Acupuncture, the Web of Science (WoS) database by Clarivate Analytics (Philadelphia) was utilized. The bibliometric analysis focused solely on original articles while excluding other types of publications. Studies categorized under the research fields of Veterinary Sciences, Agriculture, Zoology, Urban Studies, Architecture, and Geography were excluded. The search strategy employed in this investigation can be summarized as follows: [Title = (acupuncture) NOT (Veterinary Sciences AND Agriculture AND Zoology AND Urban Studies AND Architecture AND Geography)] AND [Document Type = (Article) AND Publication time: 1980–2023] (Access to articles was conducted on August 8, 2023). This search methodology enabled access to all articles featuring the term “acupuncture” within their titles.

2.2. Statistical and bibliometric analysis

Basic statistical analyses were conducted using SPSS software (Version: 22.0, SPSS Inc., Chicago, License: Hitit University). To forecast the article trends on acupuncture for the next 5 years, the Smoothing Forecaster within Microsoft Office Excel was employed. The prediction model incorporated seasonal adjustment to anticipate article trends. Bibliometric analyses were carried out using the biblioshiny interface in the bibliometrix library (http://www.bibliometrix.org/), an R Studio-Tool for science mapping, and VOSviewer, an open-access bibliometric software (Version 1.6.19, Leiden University).^[15–17] Both the Bibliometrix and VOSviewer software packages are commonly utilized in the literature to visualize and construct bibliometric networks, each offering specific advantages and differences relative to the other.

2.3. Bibliometric methods

Co-occurrence analysis is employed to examine the relationships between words that frequently appear together in the same text in scientific articles. It is useful for revealing connections between relevant terms or topics.^[10,12] Conceptual Structure analysis is used to investigate the fundamental concepts within a specific field of science and how these concepts are interrelated, making it a valuable tool for understanding the structural foundations of the discipline. Thematic Evolution analysis is employed to study how a particular subject or term has changed and evolved over time, offering insights into the changes and trends that an area has undergone. The visualizations created through thematic evolution analysis, displaying basic, emerging or declining, niche, and motor themes for different time periods, hold additional significance. Researchers can extract detailed insights from these visuals, including the declining and emerging topics within each period. Motor themes typically represent primary and predominant research areas with established and commonly studied topics, while niche themes indicate narrower or more specific subjects often centered around emerging and specialized research interests. Factor analysis is utilized to break down a large dataset into smaller and more meaningful factors, aiding in the comprehension of complex relationships and data simplification.^[15,16] WordCloud analysis visually represents the most frequently occurring words in a specific text or document, facilitating the rapid identification of key terms or concepts that need emphasis in a given topic.^[16] Citation analysis assesses how a paper is cited by other papers and includes references to other related studies. Co-citation analysis investigates whether 2 papers are cited together in a third paper, used to identify interdisciplinary interactions and key works.^[14] The H-index (Hirsch index) is a measure of an author’s (or journal’s) number of published articles, each of which has been cited in other papers at least h times. Reference publication year spectroscopy (RPYS) analysis is used to determine the development of a subject or field over time, offering insights into the historical progression of the topic and periodic trends.^[15,16]

This article does not include any studies with human participants or animals by any of the authors. Therefore, ethics committee approval is not required.

3. Results

Following the literature search, a total of 16,718 publications on the topic of acupuncture were identified in the WoS database between 1980 and 2023. Publications tagged under research areas such as Veterinary Sciences, Agriculture, Zoology, Urban Studies, Architecture, and Geography were excluded, leaving 16,261 publications for consideration. The distribution of these publications was as follows: Articles (9340, 57.4%), Review Articles (2381, 14.6%), Letters (1123, 6.9%), Meeting Abstracts (1110, 6.8%), Proceedings Papers (578, 3.5%), and the remaining in other publication types (Editorial Materials, News Items, Books, and Book Chapters, etc.). Bibliometric analyses were conducted on the 9340 articles in the Article publication category. 92.7% (n = 8658) of these articles were in English, with a small number published in other languages. Among these articles, 78.8% (n = 7362) were indexed in SCI-Expanded, 18.8% (n = 1757) in the Emerging Sources Citation Index, 7.1% (n = 663) in the Social Sciences Citation Index, and 0.2% (n = 23) in the A&HCI (Note that a single article can be indexed in multiple indexes simultaneously, such as SCI-Expanded and Social Sciences Citation Index).

3.1. Historical and future publication trends on acupuncture

A line graph in Figure 1 presents the distribution of the number of articles published on acupuncture over the years. Since 2023 has not been completed yet, it was not included in the predictive model. Furthermore, Exponential Smoothing forecast values, obtained by applying seasonal adjustment to estimate the number of articles that could be published over a 5-year period from 2023 to 2027, are also depicted in Figure 1. The model with the highest R-squared value (99%) was obtained using an exponential model. According to the exponential model findings, it is estimated that in the field of acupuncture, 626 articles (CI%: 572–680) could be published in 2023 and 718 articles (CI%: 593–843) in 2027 (Fig. 1).

Figure 1.

A line graph illustrating the change in the number of articles published on acupuncture over the years and the estimated article trend for the years 2023–2027.

3.2. Research areas on acupuncture

The research areas in which articles on acupuncture have been predominantly published (240 or more articles) are as follows, listed in descending order: Integrative Complementary Medicine (4067, 43.5%), Neurosciences (1117, 11.9%), Medicine General Internal (1030, 11%), Clinical Neurology (887, 9.4%), Medicine Research Experimental (522, 5.5%) Anesthesiology (273, 2.9%), Oncology (211, 2.2%), Multidisciplinary Sciences (204, 2.1%), Obstetrics Gynecology (191, 2%), Rehabilitation (168, 1.7%), Pharmacology Pharmacy (161, 1.7%), Health Care Sciences Services (149, 1.5%), Psychiatry (135, 1.4%), Surgery (129, 1.3%), Cell Biology (123, 1.3%), Public Environmental Occupational Health (116, 1.2%), Physiology (111, 1.1%), Nursing (99, 1%), Engineering Biomedical (98, 1%), Radiology Nuclear Medicine Medical Imaging (88, 0.9%), Biochemistry Molecular Biology (86, 0.9%), Gastroenterology Hepatology (81, 0.8%), Sport Sciences (80, 0.8%), Dermatology (70, 0.7%), and Urology Nephrology (65, 0.6%) (Note that a single article can be tagged in multiple research areas).

3.3. Global productivity of countries and international collaboration networks

The top 15 countries contributing the most articles to the literature in terms of the number of articles on acupuncture were China (Number of articles, NA: 3357), USA (1351), Korea (814), Taiwan (533), Germany (476), UK (347), Japan (338), Brazil (228), Australia (199), Sweden (197), Austria (156), Italy (143), Canada (118), Turkey (110), and Iran (92). When considering the nationality of all contributing authors to a single article, the top 15 countries with the highest productivity were as follows: China (Number of authors included in the articles: 10,803), USA (4108), South Korea (2537), Taiwan (1534), Germany (1286), UK (871), Japan (838), Brazil (629), Australia (574), Sweden (565), Iran (352), Austria (338), Canada (336), Italy (331), Turkey (308), and Israel (206).

Regarding the total number of citations, the top 15 countries receiving the most citations were as follows: China (Total citation, TC: 36,177), USA (30,671), Germany (12,643), Korea (11,286), United Kingdom (10,894), Sweden (6654), Taiwan (5585), Japan (5227), Australia (3108), Brazil (2204), Austria (2133), Canada (2108), Italy (1999), Turkey (1317), Denmark (1245), and Norway (1203). In terms of the average number of citations per article, the top 15 countries were as follows: Ireland (Average Citations Per Document, AC: 40.9), Sweden (33.8), United Kingdom (31.4), Germany (26.6), Denmark (24.4), Netherlands (23.2), USA (22.7), Tunisia (22.5), Norway (21.5), Spain (21), Canada (17.9), Pakistan (17.4), Hong Kong (16.1), Jordan (15.7), and Australia (15.6).

A color intensity map illustrating the distribution of the number of articles by countries worldwide is presented in Figure 2A, and a country collaboration network visualization map showing the results of international collaboration among the top 15 active countries is displayed in Figure 2B. The countries with the highest multiple countries publication (MCP) ratio (MCP/Total number of articles) scores, indicating the strength of international collaboration, were as follows: Switzerland (MCP ratio: 0.386), Netherlands (0.375), Ireland (0.368), Belgium (0.273), Portugal (0.261), Germany (0.246), Austria (0.237), Australia (0.236), New Zealand (0.227), Denmark (0.216), Spain (0.182), Thailand (0.182), Norway (0.179), Canada (0.178), and Sweden (0.168).

Figure 2.

(A) A graph displaying the distribution of corresponding authors’ countries for the top 15 most productive countries in comparison to the overall distribution. MCP indicates the number of documents with at least one coauthor from a different country for each country. MCP serves as a measure of the degree of international collaboration for a particular country. (B) A world map depicting the distribution of article numbers by countries and country collaboration map. In this map, the nationality of all contributing authors to the article is considered, and the color intensity is directly associated with the quantity of publications. MCP = multiple countries publication, SCP = single country publication.

3.4. Active authors on acupuncture

The top 15 most productive authors on acupuncture (with 65 or more articles published) were as follows: Park HJ. (Number of articles, NA: 128, total citations, TC: 2867), Lee H. (NA: 126, TC: 2753), Wang Y. (NA: 121, TC: 1179), Wang J. (NA: 107, TC: 1041), Zhang Y. (NA: 100, TC: 1370), Liu CZ. (NA: 92, TC: 1915), Li Y. (NA: 92, TC: 1851), Wang L. (NA: 84, TC: 1027), Macpherson H. (NA: 76, TC: 3345), Liang FR. (NA: 76, TC: 1888), Li J. (NA: 75, TC: 798), Chae Y. (NA: 72, TC: 1401), Litscher G. (NA: 67, TC: 1010), Huang Y. (NA: 66, TC: 915), and Lao LX. (NA: 65, TC: 2313). Among the top 50 most productive authors, the author with the highest total citations was Brinkhaus B. (NA: 49, TC: 3687), and the author with the highest average citations per article was Willich SN. (NA: 36, TC: 3559).

3.5. Active and influential journals on acupuncture

The 9340 articles on acupuncture were published in 1646 different scientific journals. The journals that made the most significant contributions to the literature (with more than 100 articles) were Acupuncture in Medicine (440), Evidence Based Complementary and Alternative Medicine (415), Medical Acupuncture (400), American Journal of Acupuncture (336), Journal of Alternative and Complementary Medicine (333), Acupuncture Electro Therapeutics Research (286), World Journal of Acupuncture Moxibustion (254), Deutsche Zeitschrift fur Akupunktur (252), American Journal of Chinese Medicine (238), Journal of Acupuncture and Meridian Studies (220), Trials (214), Medicine (159), Journal of Traditional Chinese Medicine (121), Complementary Therapies in Medicine (120), Journal of Acupuncture and Tuina Science (120), BMC Complementary and Alternative Medicine (118), and Chinese Journal of Integrative Medicine (113).

Among all the journals publishing articles on acupuncture, the top 50 scientific journals according to their h-index were evaluated. The journals’ h, g, and m-index values, their total citation counts, the number of articles they published, the average citations per article, and their publication start years are presented in Table 1. Additionally, the average citation counts per article published by the journals were calculated. When evaluating the journals based on the average citations per article, the most influential journals were Nature Neuroscience (Average citation per document, AC: 531), Radiology (306), Lancet Neurology (276), Jama-Journal of the American Medical Association (212), Lancet (204), Archives of Internal Medicine (194), British Medical Journal (162), Faseb Journal (159), BMJ-British Medical Journal (156), Circulation (153), JAMA Internal Medicine (149), Arthritis and Rheumatism (149), Diabetes Research and Clinical Practice (140), and Journal of Clinical Oncology (139).

Table 1.

The 50 most influential scientific journals according to the h-index on acupuncture.

Journal	h-index	g-index	m-index	TC	NA	AC	PY start
Journal of Alternative and Complementary Medicine	45	68	1.731	7899	333	23.7	1998
Pain	41	61	0.932	4741	61	77.7	1980
American Journal of Chinese Medicine	35	48	0.795	4277	238	18.0	1980
Acupuncture in Medicine	34	46	2.125	5587	440	12.7	2008
Neuroscience Letters	32	49	0.727	2894	86	33.7	1980
Plos One	29	49	1.813	2775	99	28.0	2008
Complementary Therapies in Medicine	28	44	1.167	2739	120	22.8	2000
Evidence-Based Complementary and Alternative Medicine	28	40	1.474	4643	415	11.2	2005
Acupuncture & Electro-Therapeutics Research	27	34	0.614	2744	286	9.6	1980
BMC Complementary and Alternative Medicine	27	38	1.688	2318	118	19.6	2008
Clinical Journal of Pain	24	38	0.667	1460	42	34.8	1988
Scientific Reports	24	34	2.182	1235	45	27.4	2013
Journal of Acupuncture and Meridian Studies	20	25	1.25	1611	220	7.3	2008
Chinese Journal of Integrative Medicine	19	25	0.905	1197	113	10.6	2003
Autonomic Neuroscience-Basic and Clinical	18	28	0.818	985	28	35.2	2002
Anesthesia and Analgesia	17	22	0.405	1038	22	47.2	1982
Brain Research	17	24	0.386	1008	24	42.0	1980
Neurological Research	17	25	0.654	665	29	22.9	1998
Integrative Cancer Therapies	16	26	0.889	704	36	19.6	2006
Journal of Traditional Chinese Medicine	16	21	1.067	914	121	7.6	2009
Pain Medicine	16	22	0.696	521	31	16.8	2001
Trials	16	21	1	1495	214	7.0	2008
World Journal of Gastroenterology	16	23	0.64	708	23	30.8	1999
Archives of Physical Medicine and Rehabilitation	15	19	0.349	661	19	34.8	1981
Journal of Substance Abuse Treatment	15	15	0.484	545	15	36.3	1993
Medical Acupuncture	15	20	0.882	1390	400	3.5	2007
Alternative Therapies in Health and Medicine	14	19	0.538	454	49	9.3	1998
Headache	14	17	0.333	578	17	34.0	1982
Acta Obstetricia et Gynecologica Scandinavica	13	15	0.542	599	15	39.9	2000
American Journal of Acupuncture	13	17	0.295	759	336	2.3	1980
BMJ-British Medical Journal	13	13	0.565	2027	13	155.9	2001
Cephalalgia	13	17	0.302	810	17	47.6	1981
Fertility and Sterility	13	14	0.591	877	14	62.6	2002
Neural Regeneration Research	13	18	0.813	625	84	7.4	2008
BMJ Open	12	19	1	528	70	7.5	2012
Brain Research Bulletin	12	16	0.364	486	16	30.4	1991
Frontiers in Neuroscience	12	16	1.5	386	55	7.0	2016
Journal of Pain	12	14	0.522	579	14	41.4	2001
Lasers in Medical Science	12	21	0.522	468	25	18.7	2001
Neuroimage	12	12	0.522	1348	12	112.3	2001
Rheumatology	12	13	0.48	895	13	68.8	1999
Annals of Internal Medicine	11	12	0.524	1606	12	133.8	2003
Explore-The Journal of Science and Healing	11	18	0.579	383	50	7.7	2005
Japanese Journal of Physiology	11	11	0.379	424	11	38.5	1995
Journal of Pain Research	11	21	1.571	485	48	10.1	2017
Journal of Physiological Sciences	11	16	0.611	285	18	15.8	2006
Medicine	11	15	1.222	544	159	3.4	2015
Menopause-The Journal of the North American Menopause Society	11	18	0.379	640	18	35.6	1995
JAMA-Journal of the American Medical Association	10	10	0.233	2115	10	211.5	1981
European Journal of Pain	10	15	0.5	356	15	23.7	2004

AC = average citation per document, NA = number of articles, PY = publication year, TC = total citations.

3.6. Conceptual structure analysis with trend topics, word-cloud, thematic evolution and factor analysis on acupuncture

A total of 11,927 different keywords were used in all 9340 articles on acupuncture. The 112 most frequently used keywords in articles over time (with a minimum of 24 co-occurrences) are presented in Table 2 (The table does not combine words with similar meanings, for example, “randomized controlled trial” and “RCT” or “electro-acupuncture” and “electroacupuncture.” The usage counts for each keyword are provided separately). The top 50 Author’s keywords most frequently used are also shown in Figure 3A. Search keywords directly related to the research topic, such as acupuncture, traditional Chinese medicine, complementary and alternative medicine, were not included in the analysis, and words with the same meaning, such as “randomized controlled trial” and “RCT” were merged. The cumulative trends of the top 50 keywordsPlus, over time, are depicted in Figure 3B. According to the findings of the author keyword analysis conducted in the field of acupuncture, the most extensively researched topics from the past to the present, following the main headings such as randomized controlled trial, electro-acupuncture, pain, acupuncture point, protocol, analgesia, clinical trials, placebo, rat, meta-analysis, pain management, sham acupuncture, and systematic review, are as follows: Functional magnetic resonance imaging (fMRI), stroke, laser acupuncture, depression, moxibustion, quality of life, auricular or ear acupuncture, insomnia, migraine, chronic pain, rehabilitation, cancer, low back pain, anxiety, meridians, scalp acupuncture, manual acupuncture, Parkinson’s disease, obesity, knee osteoarthritis, neural regeneration, breast cancer, hypertension, and acupuncture needles. According to the analysis results using Keyword Plus terms, the prominent topics, excluding the main headings, include prevalence, brain, mechanisms, low back pain, quality of life, women, analgesia, expression, activation, care, fMRI, validation, model, osteoarthritis, safety, depression, outcomes, auricular acupuncture, children, modulation impact, stroke, responses, reliability, acupressure, disorders, and recovery.

Table 2.

The 112 most frequently used keywords in published articles (used in at least 24 articles) on acupuncture.

Keywords	NU	Keywords	NU	Keywords	NU	Keywords	NU
acupuncture	4009	rehabilitation	67	osteoarthritis	42	hot flashes	31
randomized controlled trial	315	study protocol	66	case report	41	meridian	31
pain	297	systematic review	66	menopause	41	heart rate	30
acupuncture therapy	284	FMRI	65	randomized controlled trial	41	apoptosis	29
electro-acupuncture	248	integrative medicine	62	asthma	40	nausea	29
electroacupuncture	167	complementary and alternative medicine	61	ischemic stroke	40	physiotherapy	29
traditional chinese medicine	167	acupuncture points	60	randomized controlled trials	40	point	29
stroke	144	scalp acupuncture	60	acupressure	39	functional dyspepsia	28
depression	137	functional magnetic resonance imaging	59	irritable bowel syndrome	38	laser	28
quality of life	109	manual acupuncture	59	safety	38	massage	28
complementary medicine	108	Parkinson’s disease	59	chemotherapy	36	vascular dementia	28
auricular acupuncture	101	obesity	58	rheumatoid arthritis	36	dopamine	27
laser acupuncture	100	ear acupuncture	57	treatment	36	headache	27
insomnia	89	neural regeneration	55	blood pressure	35	cerebral palsy	26
meta-analysis	88	breast cancer	54	nerve regeneration	35	hippocampus	26
migraine	88	hypertension	53	fibromyalgia	34	infertility	26
pain management	87	acupoint	52	polycystic ovary syndrome	34	pneumothorax	26
protocol	85	acupuncture analgesia	50	pregnancy	34	review	26
chronic pain	81	acupuncture point	50	spinal cord injury	34	shoulder pain	26
cancer	77	heart rate variability	49	complementary therapies	33	acupuncture treatment	25
clinical trial	77	inflammation	49	RCT	33	children	25
moxibustion	77	acupoints	47	Alzheimer’s disease	32	mechanism	25
placebo	77	knee osteoarthritis	47	battlefield acupuncture	32	postoperative pain	25
analgesia	75	functional connectivity	46	efficacy	32	auriculotherapy	24
chinese medicine	73	rat	45	meridians	32	cerebral infarction	24
low back pain	73	rats	45	neck pain	32	neuropathic pain	24
sham acupuncture	71	alternative medicine	44	oxidative stress	32	pain measurement	24
anxiety	70	autonomic nervous system	43	fatigue	31	tinnitus	24

FMRI = functional magnetic resonance imaging, NU = Number of uses (co-occurrences).

Figure 3.

(A) A graphic illustrating the top 50 keywords most frequently used in articles from the past to the present. (B) A graphic showing the cumulative frequency of usage over time for the top 50 most frequently used keywords in articles.

Trend keyword analysis using author keywords was conducted in 3 different time periods using the Biblioshiny application. The trend keyword analysis findings for the 1980 to 2004 period are presented in Figure 4, for the 2005 to 2012 period in Figure 5, and for the 2013 to 2023 period in Figure 6. According to the findings of keyword analysis conducted over 3 different time periods to determine trending topics, it can be observed that until the year 2005, some extensively researched topics included skin diseases, evoked potentials, somatic afferent, naloxone, substance abuse, angina pectoris, skin temperature, smoking, methadone, tennis elbow, alcoholism, detoxification, and the immune system. From 2005 to 2012, particularly the topics of cocaine, hypothalamus, epilepsy, brain, addiction, in vitro fertilization, transcutaneous electrical nerve stimulation, menopause, meridians, and analgesia came to the forefront. From 2013 to 2017, the prominent topics were rheumatoid arthritis, osteoarthritis, heart rate variability, migraine, neck pain, irritable bowel syndrome, asthma, Parkinson’s disease, electro-acupuncture, breast cancer, obesity, low back pain, fMRI, moxibustion, depression, and laser acupuncture. In the last 5 years, alongside topics such as stroke, Alzheimer’s disease, Battlefield Acupuncture, knee osteoarthritis, chronic pain, polycystic ovary syndrome, chemotherapy, inflammation, wrist-ankle acupuncture, functional connectivity, integrative oncology, and COVID-19, bibliometric analyses and network meta-analyses have notably become part of the trending subjects.

Figure 4.

A graphic showing the results of keyword trend analysis from 1980 to 2004. Lines illustrate the trends in keyword usage over the years, with circle sizes indicating the frequency of usage.

Figure 5.

A graphic showing the results of keyword trend analysis from 2005 to 2012. Lines illustrate the trends in keyword usage over the years, with circle sizes indicating the frequency of usage.

Figure 6.

A graphic showing the results of keyword trend analysis from 2013 to 2023. Lines illustrate the trends in keyword usage over the years, with circle sizes indicating the frequency of usage.

A clustering analysis network visualization map was created using VOSviewer for 140 keywords used in at least 20 different articles, as shown in Figure 7A. According to the findings of cluster analysis, we identified 8 main clusters that represent significant areas of interest in the field of acupuncture based on the network map. These focal points, in descending order of cluster size, are as follows: the Red Cluster, encompassing electro-acupuncture, laser acupuncture, acupuncture points, Parkinson’s disease, Alzheimer’s disease, and neural/nerve regeneration; the Green Cluster, focusing on conditions such as chronic pain, low back pain, neck pain, and fibromyalgia; the Blue Cluster, highlighting topics related to pain management; the Yellow Cluster, addressing stroke, randomized controlled trials, study protocols, and meta-analysis/systematic reviews; the Purple Cluster, centered around obesity, polycystic ovary syndrome, allergic rhinitis, and asthma; the Turquoise Cluster, examining cancer, depression, and quality of life; the Orange Cluster, delving into fMRI and functional connectivity; and the Brown Cluster, concerning itself with heart rate-related research.

Figure 7.

(A) A network visualization map presenting the outcomes of cluster analysis. Footnote: Keywords sharing the same colors are part of the same clusters. As the number of keywords used in articles increases, the size of the circles also increases. Generally, the closer 2 terms are to each other, the stronger their relationship. (B) A network visualization map displaying historical and current trends in acupuncture. In the legend at the bottom right corner of the figure, as the terms become more “up to date,” the colors transition from blue to red (blue-green-yellow-red). The blue color indicates that a term was published in previous years, while the red color indicates that a term was published in more recent years. (C) A WordCloud representation generated using Author’s keywords. (D) A WordCloud representation generated using Keywords Plus.

To identify past and current research trends, a VOSviewer trend network visualization map showing the usage of keywords in articles published from 1980 to 2023 was presented in Figure 7B. According to the findings of trend keyword analysis conducted without separating time periods, for all years, with a threshold of a minimum number of occurrences of a keyword set at 20, it is observed that in recent years, there has been a more intensive focus on the topics of insomnia, knee osteoarthritis, functional connectivity, functional dyspepsia, pain management, pain measurement, ischemic stroke, Alzheimer’s disease, dysphagia, battlefield acupuncture, bibliometric analysis, protocol, and network meta-analysis.

WordCloud visualizations obtained using author keywords from the Biblioshiny application are displayed in Figure 7C, and WordCloud visualizations obtained using Keyword Plus are shown in Figure 7D. According to the Word Cloud analysis visualization conducted using the 50 most frequently used keywords by authors, it can be observed that electro-acupuncture takes a central position, surrounded by concepts like pain, acupuncture points, study protocol, fMRI, laser acupuncture, auricular acupuncture, depression, anxiety, analgesia, stroke, moxibustion, pain management, low back pain, insomnia, rehabilitation, obesity, and cancer. In contrast, according to the Word Cloud analysis visualization performed using Keyword Plus terms, which are added to represent more general topics or related areas of a publication and provide a broader context for its content, electro-acupuncture remains at the center, with more effective inclusion of concepts such as pain, stimulation, management, prevalence, low back pain, quality of life, brain, fMRI, therapy, and efficacy.

Thematic evolution analysis was conducted using author keywords to determine the conceptual structure of the acupuncture field. Thematic evolution for the defined trend periods in the number of publications, 1980 to 2004, 2005 to 2012, and 2013 to 2023, is presented in Figure 8A, and thematic maps obtained for all 3 periods are shown in Figure 8B. According to the thematic evolution visualization conducted to examine the tendencies of certain topics to converge or divide into multiple themes, it can be observed that in recent years, the topics of quality of life, depression, and menopause have converged around the subject of depression. Additionally, the concept of moxibustion has evolved into the domain of electro-acupuncture in recent years. It can be said that between 2005 and 2012, topics such as spinal cord injury, fMRI, heart rate variability, Parkinson’s disease, and menopause gained prominence, with these topics, except for fMRI and heart rate variability, transitioning into the field of electro-acupuncture in recent years. According to the period up to 2005, it was found that niche themes included ear acupuncture, stroke, and laser acupuncture, while motor themes encompassed auricular acupuncture, the autonomic nervous system, and rehabilitation. For the period from 2005 to 2012, niche themes consisted of spinal cord injury, Yamamoto New Scalp Acupuncture, menopause, hot flashes, breast cancer, fMRI, and acupuncture needles, while motor themes included Parkinson’s disease, neural regeneration, bee venom, migraine, and low back pain. Finally, for the 2013 to 2023 last decade, niche themes covered obesity, polycystic ovary syndrome, heart rate variability, neural and nerve regeneration, and Alzheimer’s disease, while motor themes revolved around depression, quality of life, and insomnia.

Figure 8.

(A) Thematic evolution maps for the periods 1980–2004, 2005–2012, and 2013–2023. (B) Thematic maps for the periods 1980–2004, 2005–2012, and 2013–2023. Thematic maps generated for the specified timeframes: (1) top right quadrant: motor themes; (2) bottom right quadrant: basic themes; (3) bottom left quadrant: emerging or declining themes; (4) top left quadrant: highly specialized/niche themes.

Factor analysis was performed to determine the conceptual structure of the acupuncture field using author keywords. The visualization of factor analysis conducted using Multiple Correspondence Analysis is presented in Figure 9. According to the findings of factor analysis, it was determined that the central factor comprises key topics (analgesia, pain management, chronic pain, low back pain, migraine, knee osteoarthritis, stroke, obesity, etc.), while 2 sub-factors include, respectively, depression, anxiety, insomnia, cancer, breast cancer, and quality of life (green factor), and study protocol, meta-analysis, systematic review, sham acupuncture, and randomized controlled trial (red factor).

Figure 9.

A conceptual structure map illustrating the results of factor analysis conducted through Multiple Correspondence Analysis. The origin of the map represents the average position of all column profiles, thus indicating the center of the research area (depicting common and widely shared topics).

3.7. Citation analysis

Within the 9340 articles published on acupuncture, Table 3 shares the titles of the top 25 articles that received the most citations, along with their authors, the names of the journals where they were published, publication years, the total number of citations received by the articles, and the average number of citations per year.

Table 3.

The first 25 high-impact articles based on the total number of citations on acupuncture.

No	Article	Author	Journal	PY	TC	AC
1	Acupuncture	Ramsay DJ. et al.	JAMA-Journal of the American Medical Association	1998	855	32.8
2	Introducing a placebo needle into acupuncture research	Streitberger K. and Kleinhenz J.	Lancet	1998	621	23.8
3	Adenosine A1 receptors mediate local anti-nociceptive effects of acupuncture	Goldman N. et al.	Nature Neuroscience	2010	531	37.9
4	Acupuncture modulates the limbic system and subcortical gray structures of the human brain: Evidence from fMRI studies in normal subjects	Hui KKS. et al.	Human Brain Mapping	2000	472	19.6
5	German acupuncture trials (GERAC) for chronic low back pain -: Randomized, multicenter, blinded, parallel-group trial with 3 groups	Haake M. et al.	Archives of Internal Medicine	2007	443	26.1
6	Acupuncture for patients with migraine -: A randomized controlled trial	Linde K. et al.	JAMA-Journal of the American Medical Association	2005	437	23
7	Acupuncture in patients with osteoarthritis of the knee: a randomized trial	Witt C. et al.	Lancet	2005	428	22.5
8	The impact of patient expectations on outcomes in four randomized controlled trials of acupuncture in patients with chronic pain	Linde K. et al.	Pain	2007	398	23.4
9	Effectiveness of acupuncture as adjunctive therapy in osteoarthritis of the knee - A randomized, controlled trial	Berman BM. et al.	Annals of Internal Medicine	2004	383	19.1
10	Acupuncture - from empiricism to science - functional background to acupuncture effects in pain and disease	Andersson S. and Lundeberg T.	Medical Hypotheses	1995	332	11.4
11	Characterizing acupuncture stimuli using brain imaging with fMRI - A systematic review and meta-analysis of the literature	Huang W. et al.	Plos One	2012	320	26.6
12	Safety of acupuncture: results of a prospective observational study with 229,230 patients and introduction of a medical information and consent form	Witt CM. et al.	Forschende Komplementarmedizin	2009	318	21.2
13	Acupuncture in patients with chronic low back pain - A randomized controlled trial	Brinkhaus B. et al.	Archives of Internal Medicine	2006	313	17.3
14	Central nervous pathway for acupuncture stimulation: Localization of processing with functional MR imaging of the brain - Preliminary experience	Wu MT. et al.	Radiology	1999	306	12.2
15	Lessons from a trial of acupuncture and massage for low back pain - Patient expectations and treatment effects	Kalauokalani D. et al.	Spine	2001	302	13.1
16	A randomized trial comparing acupuncture, simulated acupuncture, and usual care for chronic low back pain	Cherkin DC. et al.	Archives of Internal Medicine	2009	292	19.4
17	Characteristic and incidental (placebo) effects in complex interventions such as acupuncture	Paterson C. and Dieppe P.	BMJ-British Medical Journal	2005	290	15.2
18	Increased beta-endorphin but not metenkephalin levels in human cerebrospinal-fluid after acupuncture for recurrent pain	Clementjones V. et al.	Lancet	1980	289	6.5
19	Mechanical signaling through connective tissue: a mechanism for the therapeutic effect of acupuncture	Langevin HM. et al.	Faseb Journal	2001	280	12.1
20	Efficacy of acupuncture for the prophylaxis of migraine: a multicentre randomized controlled clinical trial	Diener HC. et al.	Lancet Neurology	2006	276	15.3
21	Acupuncture de qi, from qualitative history to quantitative measurement	Kong J. et al.	Journal of Alternative and Complementary Medicine	2007	266	15.6
22	Acupuncture and knee osteoarthritis: A three-armed randomized trial	Scharf HP. et al.	Annals of Internal Medicine	2006	265	14.7
23	Effects of electroacupuncture versus manual acupuncture on the human brain as measured by fMRI	Napadow V. et al.	Human Brain Mapping	2005	265	13.9
24	A review of the evidence for the effectiveness, safety, and cost of acupuncture, massage therapy, and spinal manipulation for back pain	Cherkin DC. et al.	Annals of Internal Medicine	2003	261	12.4
25	Expectancy and belief modulate the neuronal substrates of pain treated by acupuncture	Pariente J. et al.	Neuroimage	2005	260	13.6

AC = average citations per year, PY = publication year, TC = total citations.

3.8. Co-citation analysis

Among the entire set of 9340 articles on acupuncture, a total of 148,206 publications were cited in their reference sections. The top 10 most influential studies with 170 or more co-citations, in descending order, were Ramsay (1998, Co-citation: CC = 379), Streitberger (1998, CC = 336), Vickers (2012, CC = 279), Kaptchuk (2002, CC = 257), Zhao (2008, CC = 241), Hui (2000, CC = 223), Linde (2005, CC = 195), Witt (2005, CC = 188), Hui (2005, CC = 182), and Han (2004, CC = 175).^{[2–4,6,18–23]} The findings of the RPYS analysis, conducted to identify the years when important results were published, are presented in Figure 10.

Figure 10.

A line graph presenting the findings of Reference Publication Year Spectroscopy (RPYS).

4. Discussion

When evaluating the distribution of articles on the acupuncture from 1980 to 2023, 3 distinct publication trends were observed, namely 1980 to 2004, 2005 to 2012, and 2013 to 2023. During the period of 1980 to 2004, an average of 75 articles (min–max: 40–123) were published. Starting from the year 2005, there was an increasing trend in the number of articles, with an average of 279 articles (min–max: 189–370) published during the period of 2005 to 2012. Another increase in the number of articles began in 2013, resulting in an average of 488 articles (min–max: 416–608) published during the period of 2013 to 2023. When assessing the findings of a 5-year forecast for 2023 and beyond, it is evident that article productivity on acupuncture will continue to follow an exponential upward trend.

Analyzing the article productivity of different countries worldwide in the field of acupuncture, it can be stated that the top 15 contributing countries are predominantly major economies. In the literature, various bibliometric studies have reported a significant correlation between a country’s economic size and its article productivity.^[10–13] However, unlike other bibliometric studies, the higher efficiency of Eastern Asian countries, especially China, in article productivity can be directly attributed to acupuncture being an integral part of traditional Chinese medicine with a history spanning thousands of years. Acupuncture is widely accepted as a medical practice in Eastern Asian countries, and it holds a significant place in traditional medical education. Eastern Asian countries, particularly China, have increased their support for acupuncture research in recent years.^[24] According to the findings, it can be said that Western developed countries have also shown increased interest in acupuncture research in recent years due to the rising article productivity. While the total citation counts of countries were in parallel with their article productivity rankings, the average citation counts per article showed that the top 15 countries in this regard did not include Eastern Asian countries. Factors such as research infrastructure, the training of scientists, international research collaborations, and the number of influential scientific journals in the country may explain why countries like Ireland, Sweden, and the United Kingdom, which are the top 3 most influential countries, have high citation counts in acupuncture research.^[25] Furthermore, these countries use the most commonly used scientific communication language globally, which means that their research can reach a broader international audience. When examining the collaborative authorship network map of countries, it is generally observed that global collaborations are widespread among Eastern Asian countries, the USA, European countries, Canada, and Australia. However, when evaluating the collaboration findings obtained by dividing the number of collaborative publications by the total number of publications, it can be said that European countries engage in more collaborations.

In the findings section, the journals that make the most significant contributions to the literature on acupuncture, the ranking of the most effective journals based on their h-index, and the average citation counts per article published by these journals were presented. The h-index takes into account both the number of publications and their impact, with a higher h-index indicating a greater number of highly influential publications. Generally, a higher average citation count per article indicates that the journal’s articles receive more attention and are more impactful.^[15,16] For researchers who are in the process of preparing publications and prioritize their articles receiving greater impact after publication, we recommend evaluating the global productivity of journals, their h-index values, and both the total and average citation counts.

The analyses conducted based on the keywords present in the articles highlight significant and consistently researched areas within the acupuncture domain. Among these areas, clinical trials, pain management, studies focusing on the treatment of specific ailments, and investigations into the effects of acupuncture stand out prominently. Moreover, there’s a discernible shift in the popularity of specific topics over time; for instance, the emergence of topics such as ischemic stroke, functional connectivity, Alzheimer’s, and COVID-19 in recent years has become noticeable. Another noteworthy aspect is the clustering and factor analyses revealed by these examinations. These analyses demonstrate how specific subjects are interrelated and grouped together. For instance, there’s evidence of clusters formed around particular diseases or the grouping of topics sharing similar research focuses under a common factor. Thematic evolution analyses concerning this subject reveal the developmental trajectory of key topics and their evolution toward specific domains. These analyses offer vital insights into how acupuncture research has evolved over time and which subjects have gained prominence. The overall assessment of these analyses indicates the broad spectrum of research conducted in the acupuncture field, the varying prominence of specific topics over time, and the concentrated efforts of researchers around different focal points. These findings could serve as significant guiding markers for future research endeavors, guiding the focus of forthcoming studies in acupuncture.

When the analyzed articles were evaluated based on their total citation counts, it was determined that the most cited study was the one titled “Acupuncture” by Ramsay et al (1998) published in JAMA.^[18] The second most influential study was “Introducing a placebo needle into acupuncture research” by Streitberger and Kleinhenz (1998), published in Lancet.^[2] The third most influential study was “Adenosine A1 receptors mediate local anti-nociceptive effects of acupuncture” by Goldman et al (2010), published in Nature Neuroscience.^[26] When the articles were assessed based on their average citations per year, the top 2 most effective studies were Goldman et al (2010) and Ramsay et al (1998). The third most influential study was “Effect of acupuncture vs sham acupuncture or waitlist control on joint pain related to aromatase inhibitors among women with early-stage breast cancer a randomized clinical trial” by Hershman et al,^[27] published in JAMA. Despite not making it to the ranking of effective articles based on total citation count, other notable articles published in recent years were the ones by Zhao et al and Chen et al based on their average citations per year.^[28,29] The importance of average citations per year is to correct the advantage that older documents have in accumulating citations over more extended periods compared to newer documents.^[15,16] Based on the co-citation numbers, considering the common citations made by all the analyzed articles, the most effective studies were those of Ramsay (1998), Streitberger (1998), Vickers (2012), Kaptchuk (2002), Zhao (2008), Hui (2000), Linde (2005), Witt (2005), Hui (2005), and Han (2004).^{[2–4,6,18–23]} We recommend that researchers interested in this topic prioritize reading these studies, identified through citation and co-citation analyses. According to the RPYS analysis conducted on the historical development of the acupuncture topic, it can be said that academic interest in acupuncture increased after 1970, with a more substantial growth in interest, particularly after 1991, reaching its peak in academic interest in 2008 and 2010.

Bibliometric analyses of acupuncture have been conducted for various diseases in the literature. Yang et al^[30] performed bibliometric analysis for the treatment of cardiovascular diseases, Ling et al^[31] for cancer pain management, Fu et al^[32] for dysmenorrhea treatment, Chen et al^[33] for shoulder pain treatment, Zhu et al^[34] for tension-type headache treatment, Guo et al^[35] for allergic rhinitis treatment, Zhang et al^[36] for stroke, and Lu et al^[37] for myofascial pain syndrome treatment. In our study, we conducted bibliometric analysis for a wide range of articles on the general topic of acupuncture over an extended period. Additionally, based on keyword analyses, we identified the trend periods for acupuncture in various treatments. One significant advantage of our study is its comprehensiveness in terms of both the number of articles and the time span covered. One limitation of this research may be that we chose to use only the WoS database for the literature search. However, it has been emphasized in many studies that Pubmed database is not preferred for bibliometric analyses because citation and co-citation analyses cannot be performed.^[10–14] It is also noted that Scopus database indexes some low-impact journals.^[37,38] WoS database, on the other hand, indexes articles published in higher-impact journals (the majority of which are SCI-expanded) compared to the Scopus database.^[12,13,39] In our study, we preferred WoS over Scopus, 2 databases with relative advantages in different aspects.

5. Conclusion

In this study, we have presented a bibliometric analysis of 9340 articles on acupuncture, which has shown an exponential growth trend in recent years. This article provides an important bibliometric analysis that will help us understand current approaches and future research directions in the field of acupuncture. Research leadership in acupuncture was established by East Asian countries such as China, South Korea, Taiwan, and Japan, as well as by the USA, Brazil, Australia, Canada, and several European countries, including the Germany, United Kingdom, Sweden, Austria, and Italy. Furthermore, significant international collaborations in this field were observed.

Over the years, a wide range of research topics have been extensively explored in acupuncture literature. Prominent themes include acupuncture methods and applications, pain management, the nervous system and acupuncture, mental health and acupuncture, as well as quality of life and general health. These topics have been extensively investigated to understand the effects of acupuncture in various medical fields and in the treatment of health issues, resulting in a wealth of knowledge in the literature. The association of acupuncture with this diverse range of topics reflects its therapeutic potential and application areas. In recent years, trends in acupuncture research have focused on neurological health problems, oncology and cancer treatment, women’s health and hormonal issues, sleep disorders and digestive problems, and the quantitative and qualitative evaluation of acupuncture research. Notably, there has been a noticeable increase in the number of bibliometric analyses and network-meta analyses.

According to our factor analysis findings, the acupuncture literature is grouped around 3 main sub-factors. The primary factor encompasses topics related to the effectiveness/applicability of the treatment method for various medical conditions and the general principles of acupuncture, including acupuncture methods and points. The second factor encompassed research specifically related to acupuncture in the context of mental health and quality of life. This factor indicates that acupuncture is considered as an effective alternative treatment method for specific medical conditions or psychological problems. The third sub-factor highlights the prominence of topics such as meta-analysis, systematic reviews, study protocols, randomized controlled trials, and sham acupuncture in acupuncture literature. This sub-factor addresses the qualitative and quantitative aspects of acupuncture research. Meta-analysis and systematic reviews play an essential role in synthesizing existing research and drawing general conclusions. At the same time, study protocols and randomized controlled trials indicate that acupuncture research aims to maintain high scientific standards and achieve reliable results. Sham acupuncture emphasizes the importance of placebo controls and contributes to the objective evaluation of the effects of real treatment. This can further enhance the acceptance of acupuncture in the medical field and enable more patients to benefit from this alternative treatment method.

Author contributions

Conceptualization: Coşkun Öztekin, Aynure Öztekin.

Data curation: Coşkun Öztekin, Aynure Öztekin.

Formal analysis: Coşkun Öztekin, Aynure Öztekin.

Investigation: Coşkun Öztekin, Aynure Öztekin.

Methodology: Coşkun Öztekin, Aynure Öztekin.

Resources: Coşkun Öztekin, Aynure Öztekin.

Software: Coşkun Öztekin, Aynure Öztekin.

Supervision: Coşkun Öztekin, Aynure Öztekin.

Validation: Coşkun Öztekin, Aynure Öztekin.

Visualization: Coşkun Öztekin, Aynure Öztekin.

Writing – original draft: Coşkun Öztekin, Aynure Öztekin.

Writing – review & editing: Coşkun Öztekin, Aynure Öztekin.