Abstract
Introduction
Onychomycosis represents half of nail disorders seen in clinical practice. Despite its high prevalence, a bibliometric analysis has not been performed. We aimed to identify the top 100 highly cited onychomycosis publications over the last 50 years to better understand research trends.
Methods
SCOPUS was searched for onychomycosis publications, using “onychomycosis” and “nail fungus” 1/1/1972-12/31/22 on 3/25/23. Top 100 highly cited publications were recorded and ranked by total citation count.
Results
Total citation count was 13,456, with the top 10 articles with highest citation count/year having average 28.7 citations/year. Most articles were published in high IF journals. From 1982 to 2011 (no treatment articles – 1972–1981), there was an 8.6% increase in articles discussing treatment. Overall, 42% of first authors were female.
Conclusion
We found an overall increase in articles discussing onychomycosis therapies over time, with the majority published in high IF journals. We also found a relatively greater percentage of female first authors compared to studies on other dermatologic topics. While total citation count remains a widely used metric of impact in bibliometric studies, average citation count/year may be a better measure of impact and should be considered in future studies.
Keywords: Bibliometric analysis, Citation, Impact factor, Nail fungus, Onychomycosis
Introduction
Onychomycosis is the most common nail condition, accounting for 50% of all nail disorders seen in clinical practice, with worldwide prevalence of 5.5% [1, 2]. Onychomycosis may negatively affect patient’s quality of life [3], by causing pain, impaired functionality, secondary bacterial infections, and/or social embarrassment. Bibliometric studies have been performed for dermatological conditions including atopic dermatitis, hidradenitis suppurativa, and nail psoriasis. Despite the high prevalence of onychomycosis, a bibliometric analysis of onychomycosis literature has not been previously performed. We aimed to identify the top 100 highly cited onychomycosis publications over the last 50 years to analyze citations, content, and authorship to better understand research trends.
Materials and Methods
The SCOPUS database [4] was accessed on 3/25/23 for onychomycosis publications (searching field category “onychomycosis” and “nail fungus”) from 1/1/1972 to 12/31/22. The top 100 highly cited publications were recorded and ranked by total citation count. Articles not relevant to onychomycosis were excluded. Authorship, journal title, most recently published journal impact factor (IF), article type, study topic, year of publication, total citation count, and average citation count per year were recorded. Country affiliation and gender of first author were obtained via Google search of author name. χ2 analysis was performed to compare frequencies (p < 0.05). Ethical approval and consent were not required as this study was based on publicly available data.
Results
For the top 100 highly cited onychomycosis publications (Table 1), the total citation count was 13,456, with the top 10 most cited articles accounting for 28.8% of the total citation count (Table 2). The top 10 articles with the highest citation count/year had an average of 28.7 citations per year and were all published post-2010, except for one publication in 1995. From 1972 to 2022, the majority of articles were published between 2002 and –2011 (38%), followed by 1992–2001 (33%), 2012–2022 (18%), 1982–1991 (2%), and 1972–1981 (9%) (Fig. 1). The top 100 highly cited articles were published in 40 different journals, with most published in the Journal of the American Academy of Dermatology (n = 20), followed by the British Journal of Dermatology (n = 9). The mean and median IF of journals were 12.25 and 9.55, respectively (range 0.99–176.1). The most frequent article types were reviews (49%), followed by comparative studies (13%) and randomized-controlled trials (11%). The most frequent topics included treatment (38%), overview of onychomycosis (31%), and diagnosis (16%). From 1982 to 2011 (no treatment articles – 1972–1981), there was an 8.6% increase in articles discussing treatment, and from 1972 to 2011 an 11.5% increase in overview articles (Fig. 2). Articles originated from 28 different countries, with the USA (27%), UK (10%), Canada (9%), and Germany (9%) as the most frequently contributing countries.
Table 1.
Top 100 cited onychomycosis publications (1972–2022)
| Rank | Title | Journal | Year | Times cited | Times cited/year | Article type |
|---|---|---|---|---|---|---|
| 1 | The dermatophytes | Clinical Microbiology Reviews | 1995 | 935 | 33.4 | Review |
| 2 | The biology and chemistry of antifungal agents: A review | Bioorganic and Medicinal Chemistry | 2012 | 496 | 45.1 | Review |
| 3 | Onychomycosis: Pathogenesis, diagnosis, and management | Clinical Microbiology Reviews | 1998 | 454 | 18.2 | Review |
| 4 | A large-scale North American study of fungal isolates from nails: The frequency of onychomycosis, fungal distribution, and antifungal susceptibility patterns | Journal of the American Academy of Dermatology | 2000 | 444 | 19.3 | Multicenter |
| 5 | Prevalence and epidemiology of toenail onychomycosis in diabetic subjects: A multicentre survey | British Journal of Dermatology | 1998 | 301 | 12.0 | Multicenter |
| 6 | Onychomycosis | Archives of Dermatology | 1972 | 278 | 5.5 | Review |
| 7 | Terbinafine: A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in superficial mycoses | Drugs | 1992 | 258 | 8.3 | Review |
| 8 | Onychomycosis, tinea pedis and tinea manuum caused by non-dermatophytic filamentous fungi | Mycoses | 1989 | 245 | 7.2 | Case series |
| 9 | Comparison of diagnostic methods in the evaluation of onychomycosis | Journal of the American Academy of Dermatology | 2003 | 234 | 11.7 | Comparative |
| 10 | Prevalence of onychomycosis in patients attending a dermatology clinic in Northeastern Ohio for other conditions | Archives of Dermatology | 1997 | 229 | 8.8 | Cross-sectional survey |
| 11 | Efinaconazole 10% solution in the treatment of toenail onychomycosis: Two phase III multicenter, randomized, double-blind studies | Journal of the American Academy of Dermatology | 2013 | 216 | 21.6 | RCT |
| 12 | Nails and fungi | British Journal of Dermatology | 1976 | 212 | 4.5 | Review |
| 13 | A U.S. epidemiologic survey of superficial fungal diseases | Journal of the American Academy of Dermatology | 1996 | 210 | 7.8 | Survey |
| 14 | Mycology-an update. Part 1: Dermatomycoses: Causative agents, epidemiology and pathogenesis | JDDG – Journal of the German Society of Dermatology | 2014 | 203 | 22.6 | Review |
| 15 | Dermatophyte infections | American Family Physician | 2003 | 191 | 9.6 | Review |
| 16 | Systematic review of nondermatophyte mold onychomycosis: Diagnosis, clinical types, epidemiology, and treatment | Journal of the American Academy of Dermatology | 2012 | 189 | 17.2 | Review |
| 17 | Fungal planet description sheets: 400–468 | Persoonia: Molecular Phylogeny and Evolution of Fungi | 2016 | 187 | 26.7 | Review |
| 18 | Antifungal pulse therapy for onychomycosis: A pharmacokinetic and pharmacodynamic investigation of monthly cycles of 1-week pulse therapy with itraconazole | Archives of Dermatology | 1996 | 187 | 6.9 | RCT |
| 19 | Guidelines for treatment of onychomycosis | British Journal of Dermatology | 2003 | 179 | 9.0 | Guidelines |
| 20 | Mycology of nail disorders | Journal of the American Academy of Dermatology | 1994 | 171 | 5.9 | Review |
| 21 | Onychomycosis | Clinics in Dermatology | 2010 | 170 | 13.1 | Review |
| 22 | Fungal infections of the nail | Seminars in Dermatology | 1991 | 157 | 4.9 | Review |
| 23 | Alternaria infections: Laboratory diagnosis and relevant clinical features | Clinical Microbiology and Infection | 2008 | 155 | 10.3 | Review |
| 24 | Clinical features of human infection with scedosporium inflatum | Clinical Infectious Diseases | 1992 | 152 | 4.9 | Case series |
| 25 | Methods for diagnosing onychomycosis: A comparative study and review of the literature | Archives of Dermatology | 2000 | 148 | 6.4 | Review |
| 26 | Onychomycosis: Clinical overview and diagnosis | Journal of the American Academy of Dermatology | 2019 | 144 | 36.0 | Review |
| 27 | Epidemiology and clinical classification of onychomycosis | Journal of the European Academy of Dermatology and Venereology | 2005 | 134 | 7.4 | Comparative |
| 28 | Antifungal agents | Medical Journal of Australia | 2007 | 131 | 8.2 | Review |
| 29 | Randomized double blind comparison of terbinafine and itraconazole for treatment of toenail tinea infection | British Medical Journal | 1995 | 129 | 4.6 | RCT |
| 30 | Onychomycosis in the 21st century: An update on diagnosis, epidemiology, and treatment | Journal of Cutaneous Medicine and Surgery | 2017 | 126 | 21.0 | Review |
| 31 | Onychomycosis: Treatment and prevention of recurrence | Journal of the American Academy of Dermatology | 2019 | 123 | 30.8 | Review |
| 32 | Identification of dermatophyte species causing onychomycosis and tinea pedis by MALDI-TOF mass spectrometry | Experimental Dermatology | 2008 | 122 | 8.1 | Comparative |
| 33 | Comparison of in vitro antifungal activities of efinaconazole and currently available antifungal agents against a variety of pathogenic fungi associated with onychomycosis | Antimicrobial Agents and Chemotherapy | 2013 | 120 | 12.0 | Comparative |
| 34 | Onychomycosis: A proposed revision of the clinical classification | Journal of the American Academy of Dermatology | 2011 | 119 | 9.9 | Editorial |
| 35 | Deep neural networks show an equivalent and often superior performance to dermatologists in onychomycosis diagnosis: Automatic construction of onychomycosis datasets by region-based convolutional deep neural network | Antimicrobial Agents and Chemotherapy | 2018 | 118 | 23.6 | Comparative |
| 36 | Five-hour diagnosis of dermatophyte nail infections with specific detection of Trichophyton rubrum | Journal of Clinical Microbiology | 2007 | 117 | 7.3 | Validation |
| 37 | A new classification system for grading the severity of onychomycosis: Onychomycosis severity index | Archives of Dermatology | 2011 | 116 | 9.7 | Consensus |
| 38 | Candida onychomycosis—an evaluation of the role of Candida species in nail disease | British Journal of Dermatology | 1988 | 115 | 3.3 | Review |
| 39 | Toenail onychomycosis: Current and future treatment options | Dermatologic Therapy | 2007 | 114 | 7.1 | Review |
| 40 | In vitro penetration of a novel oxaborole antifungal (AN2690) into the human nail plate | Journal of Pharmaceutical Sciences | 2007 | 111 | 6.9 | Comparative |
| 41 | Non-dermatophytes in onychomycosis of the toenails | British Journal of Dermatology | 1997 | 111 | 4.3 | RCT |
| 42 | Causative agents of onychomycosis – A retrospective study | JDDG – Journal of the German Society of Dermatology | 2006 | 110 | 6.5 | Retrospective |
| 43 | Other fungi causing onychomycosis | Clinics in Dermatology | 2010 | 109 | 8.4 | Review |
| 44 | Superficial fungal infections in 102 renal transplant recipients: A case-control study | Journal of the American Academy of Dermatology | 2003 | 109 | 5.5 | Case-control |
| 45 | An evaluation of itraconazole in the management of onychomycosis | British Journal of Dermatology | 1988 | 109 | 3.1 | RCT |
| 46 | Ciclopirox: Recent nonclinical and clinical data relevant to its use as a topical antimycotic agent | Drugs | 2010 | 108 | 8.3 | Review |
| 47 | Bifonazole: A review of its antimicrobial activity and therapeutic use in superficial mycoses | Drugs | 1989 | 105 | 3.1 | Review |
| 48 | Onychomycosis: A critical study of techniques and criteria for confirming the etiologic significance of nondermatophytes | Medical Mycology | 2005 | 104 | 5.8 | Review |
| 49 | Twelve weeks of continuous oral therapy for toenail onychomycosis caused by dermatophytes: A double-blind comparative trial of terbinafine 250 mg/day versus itraconazole 200 mg/day | Journal of the American Academy of Dermatology | 1998 | 104 | 4.2 | RCT |
| 50 | Laser treatment of onychomycosis using a novel 0.65-millisecond pulsed Nd:YAG 1064-nm laser | Journal of Cosmetic and Laser Therapy | 2011 | 103 | 8.6 | RCT |
| 51 | Terbinafine. An update of its use in superficial mycoses | Drugs | 1999 | 102 | 4.3 | Review |
| 52 | Nail changes in patients infected with human immunodeficiency virus: A prospective controlled study | Archives of Dermatology | 1998 | 102 | 4.1 | Prospective |
| 53 | Fungal nail disease | New England Journal of Medicine | 2009 | 100 | 7.1 | Review |
| 54 | Nail incorporation kinetics of terbinafine in onychomycosis patients | Clinical and Experimental Dermatology | 1995 | 100 | 3.6 | Pharmacokinetic |
| 55 | Terbinafine: A review of its use in onychomycosis in adults | American Journal of Clinical Dermatology | 2003 | 98 | 4.9 | Review |
| 56 | Onychomycosis in Denmark: Prevalence of fungal nail infection in general practice | Mycoses | 2004 | 94 | 4.9 | Observational |
| 57 | Treatment failures and relapses in onychomycosis: A stubborn clinical problem | Dermatology | 2003 | 94 | 4.7 | Review |
| 58 | Diagnostic techniques for confirming onychomycosis | Journal of the American Academy of Dermatology | 1996 | 93 | 3.4 | Review |
| 59 | Causative pathogens in onychomycosis and the possibility of treatment resistance: A review | Journal of the American Academy of Dermatology | 1998 | 90 | 3.6 | Review |
| 60 | The future of onychomycosis therapy may involve a combination of approaches | British Journal of Dermatology, Supplement | 2001 | 89 | 4.0 | Review |
| 61 | Dermatophyte resistance to antifungal drugs: Mechanisms and prospectus | Frontiers in Microbiology | 2018 | 88 | 17.6 | Review |
| 62 | Topical therapy for fungal infections | American Journal of Clinical Dermatology | 2004 | 87 | 4.6 | Review |
| 63 | In vitro activity of fluconazole, itraconazole, voriconazole and terbinafine against fungi causing onychomycosis | Clinical and Experimental Dermatology | 2010 | 82 | 6.3 | Experimental |
| 64 | Forty-eight-hour diagnosis of onychomycosis with subtyping of Trichophyton rubrum strains | Journal of Clinical Microbiology | 2006 | 82 | 4.8 | Molecular diagnostic |
| 65 | Common tinea infections in children | American Family Physician | 2008 | 81 | 5.4 | Review |
| 66 | Fungal nail infections (onychomycosis): A never-ending story? | PLOS Pathogens | 2014 | 80 | 8.9 | Review |
| 67 | Fusarium spp. as agents of onychomycosis in immunocompetent hosts | International Journal of Dermatology | 2007 | 80 | 5.0 | Observational |
| 68 | A risk-benefit assessment of the newer oral antifungal agents used to treat onychomycosis | Drug Safety | 2000 | 80 | 3.5 | Review |
| 69 | Amorolfine: A review of its pharmacological properties and therapeutic potential in the treatment of onychomycosis and other superficial fungal infections | Drugs | 1995 | 80 | 2.9 | Review |
| 70 | Onychomycosis | Dermatologic Clinics | 1985 | 80 | 2.1 | Review |
| 71 | Onychomycosis: A review | Journal of Fungi | 2015 | 79 | 9.9 | Review |
| 72 | Treatment of onychomycosis using a submillisecond 1064-nm neodymium:yttrium-aluminum-garnet laser | Journal of the American Academy of Dermatology | 2013 | 78 | 7.8 | Comparative |
| 73 | Cost-effectiveness of diagnostic tests for toenail onychomycosis: A repeated-measure, single-blinded, cross-sectional evaluation of 7 diagnostic tests | Journal of the American Academy of Dermatology | 2006 | 78 | 4.6 | Comparative |
| 74 | Update on the management of onychomycosis: Highlights on the Third Annual International Summit on Cutaneous Antifungal Therapy | Clinical Infectious Diseases | 1996 | 78 | 2.9 | Review |
| 75 | Onychomycosis: A review | Journal of the European Academy of Dermatology and Venereology | 2020 | 77 | 25.7 | Review |
| 76 | Rare and new etiological agents revealed among 178 clinical Aspergillus strains obtained from Czech patients and characterized by molecular sequencing | Medical Mycology | 2012 | 77 | 7.0 | Observational |
| 77 | Histopathological diagnosis of onychomycosis by periodic acid-Schiff-stained nail clippings | British Journal of Dermatology | 2003 | 76 | 3.8 | Comparative |
| 78 | Present and potential diagnostic techniques in onychomycosis | Journal of the American Academy of Dermatology | 1996 | 76 | 2.8 | Review |
| 79 | Usefulness of histological examination for the diagnosis of onychomycosis | Dermatology | 2001 | 75 | 3.4 | Comparative |
| 80 | Pharmacokinetics of antifungal agents in onychomycoses | Clinical Pharmacokinetics | 2001 | 75 | 3.4 | Review |
| 81 | Photodynamic treatment of the dermatophyte Trichophyton rubrum and its microconidia with porphyrin photosensitizers | Photochemistry and Photobiology | 2004 | 72 | 3.8 | Experimental |
| 82 | Systematic review of topical treatments for fungal infections of the skin and nails of the feet | British Medical Journal | 1999 | 72 | 3.0 | Systematic review |
| 83 | Terbinafine in onychomycosis of the toenail: A novel treatment protocol | Journal of the American Academy of Dermatology | 1995 | 72 | 2.6 | RCT |
| 84 | Onychomycosis: Diagnosis and management | Indian Journal of Dermatology, Venereology and Leprology | 2011 | 71 | 5.9 | Review |
| 85 | Study of onychomycosis: Prevailing fungi and pattern of infection | Indian Journal of Medical Microbiology | 2007 | 71 | 4.4 | Observational |
| 86 | A method for the determination of drug effectiveness in onychomycosis: Trials with ketoconazole and griseofulvin ultramicrosize | Journal of the American Academy of Dermatology | 1983 | 71 | 1.8 | RCT |
| 87 | Confocal laser scanning microscopy as a new valuable tool in the diagnosis of onychomycosis – comparison of six diagnostic methods | Mycoses | 2013 | 70 | 7.0 | Comparative |
| 88 | Fungal melanonychia | Journal of the American Academy of Dermatology | 2012 | 70 | 6.4 | Review |
| 89 | Therapeutic efficacy of topically applied KP-103 against experimental tinea unguium in guinea pigs in comparison with amorolfine and terbinafine | Antimicrobial Agents and Chemotherapy | 2002 | 70 | 3.3 | Comparative |
| 90 | Onychomycosis in Lahore, Pakistan | International Journal of Dermatology | 1999 | 70 | 2.9 | Observational |
| 91 | Molds in onychomycosis | International Journal of Dermatology | 1993 | 70 | 2.3 | Experimental |
| 92 | Epidemiology of dermatophyte infections in Stockholm, Sweden: A retrospective study from 2005–2009 | Medical Mycology | 2011 | 69 | 5.8 | Observational |
| 93 | Candidal onychomycosis: A mini-review | Mycopathologia | 2009 | 69 | 4.9 | Review |
| 94 | A phase I/II randomized, double-blind, placebo-controlled, dose-ranging study evaluating the efficacy, safety and pharmacokinetics of ravuconazole in the treatment of onychomycosis | Journal of the European Academy of Dermatology and Venereology | 2005 | 69 | 3.8 | RCT |
| 95 | Utility of inoculum counting (Walshe and English criteria) in clinical diagnosis of onychomycosis caused by nondermatophytic filamentous fungi | Journal of Clinical Microbiology | 2001 | 68 | 3.1 | Observational |
| 96 | Study of onychomycosis in Cordoba, Spain: Prevailing fungi and pattern of infection | Mycopathologia | 1997 | 68 | 2.6 | Comparative |
| 97 | Short-duration treatment of fingernail dermatophytosis: A randomized, double-blind study with terbinafine and griseofulvin | Journal of the American Academy of Dermatology | 1995 | 68 | 2.4 | RCT |
| 98 | Determination of terbinafine in nail samples during systemic treatment for onychomycoses | British Journal of Dermatology | 1990 | 68 | 2.1 | Experimental |
| 99 | Dermatophyte onychomycosis in children | Clinical and Experimental Dermatology | 1989 | 68 | 2.0 | Laboratory based |
| 100 | The susceptibility of dermatophytes to photodynamic treatment with special focus on Trichophyton rubrum | Photochemistry and Photobiology | 2011 | 67 | 5.6 | Review |
RCT, Randomized-controlled trial.
Table 2.
Characteristics of 100 cited onychomycosis publications (1972–2022)
| Publication information | Publication (n or %) | Publication information | Publication (n or %) |
|---|---|---|---|
| Journal title (IF a ) | Article type | ||
| Journal of the American Academy of Dermatology (11.53) | 20 | Review (literature/systematic) | 49 |
| British Journal of Dermatology (11.11) | 9 | Comparative | 13 |
| Archives of Dermatology (11.82) | 6 | RCT | 11 |
| Drugs (9.55) | 5 | Observational | 7 |
| Journal of the European Academy of Dermatology and Venereology (9.23) | 3 | Experimental | 5 |
| Medical Mycology (3.75) | 3 | Case series | 2 |
| Mycoses (4.93) | 3 | Multicenter | 2 |
| Clinical and Experimental Dermatology (3.47) | 3 | Otherb | 11 |
| Journal of Clinical Microbiology (11.68) | 3 | Study topic | |
| International Journal of Dermatology (1.31) | 3 | Treatment | 38 |
| Antimicrobial Agents and Chemotherapy (5.95) | 3 | General | 31 |
| Clinical Infectious Diseases (21.00) | 2 | Diagnosis | 16 |
| British Medical Journal (96.22) | 2 | Etiology | 9 |
| American Journal of Clinical Dermatology (7.40) | 2 | Epidemiology | 4 |
| American Family Physician (1.97) | 2 | Risk factors | 1 |
| Clinical Microbiology Reviews (50.13) | 2 | Novel fungal species | 1 |
| Clinics in Dermatology (2.47) | 2 | Country of first author affiliation | |
| Dermatology (1.10) | 2 | USA | 27 |
| JDDG – Journal of the German Society of Dermatology (5.23) | 2 | UK | 10 |
| Photochemistry and Photobiology (2.21) | 2 | Canada | 9 |
| Mycopathologia (3.79) | 2 | Germany | 9 |
| Otherc | 18 | Australia | 4 |
| Citation count | Belgium | 4 | |
| Total | 13,456 | Italy | 4 |
| Mean | 134.6 | India | 4 |
| Median | 102.5 | New Zealand | 3 |
| Range | 67-496 | Brazil | 2 |
| Average citations per year | Wales | 2 | |
| Mean | 8.473 | France | 2 |
| Median | 5.8 | Netherlands | 2 |
| Range | 1.8–45.1 | Spain | 2 |
| IF a | Mexico | 2 | |
| Mean | 12.25 | Otherd | 12 |
| Median | 9.55 | Gender of first author | |
| Range | 0.99–176.1 | Male | 56 |
| Female | 42 | ||
| Unknown | 2 |
RCT, Randomized-controlled trial.
aThe most recent IF on record was used for each journal.
bIncludes editorial, guidelines, pharmacokinetic, cross-sectional survey, prospective, survey, molecular diagnostics.
cIncludes New England Journal of Medicine (176.10), Persoonia: Molecular Phylogeny and Evolution of Fungi, Clinical Microbiology and Infection (11.26), Indian Journal of Dermatology, Venereology and Leprology (2.55), Indian Journal of Medical Microbiology (0.99), Clinical Pharmacokinetics (6.45), Journal of Cutaneous Medicine and Surgery (2.09), Bioorganic and Medicinal Chemistry (3.64), Dermatologic Clinics (3.21), Dermatologic Therapy (3.86), Journal of Pharmaceutical Sciences (3.78), PLOS Pathogens (7.46), Seminars in Dermatology (1.31), Journal of Fungi (5.72), Journal of Cosmetic and Laser Therapy (1.11), Drug Safety (5.61), Frontiers in Microbiology (6.06), Experimental Dermatology (3.47), Medical Journal of Australia (7.70).
dIncludes Austria, Bulgaria, Columbia Czech Republic, Poland, Denmark, Japan, Pakistan, South Africa, Sri Lanka, Sweden, Turkey.
Fig. 1.
Rate of publications and citations (1972–2022).
Fig. 2.
Number of top cited publications by time frame and study topic (1972–2021).
Overall, 56% of first authors were male, 42% were female, 2% were unknown, and there was no significant relationship between gender and first author role (p > 0.05). The total citation count for publications with male versus female first authors was 7,465 versus 5,851 (χ2 = 4.841, p = 0.0278), and the median journal IF for publications with male versus female first authors was 9.39 versus 10.33. There was no statistically significant difference in article type or study topic between male and female first authors (p > 0.05).
Discussion
We found that for the top 100 highly cited onychomycosis publications, the most frequent study topic was treatment, with an increase in onychomycosis articles discussing treatment over time. Similarly, in a bibliometric analysis of the top 50 highly cited nail psoriasis publications, the most frequent (48%) study topic was treatment, which might be due to increased approval of new psoriasis therapies [5]. Similarly, there have been novel developments in the treatment of onychomycosis. Terbinafine was approved by the Food and Drug Administration (FDA) for treatment of onychomycosis in 1996, and topical ciclopirox was approved in 1999 [6]. Fifteen years following the approval of topical ciclopirox, topical efinaconazole [7] and tavaborole [8] received FDA approval in 2014. Therapies being studied of onychomycosis treatment include the systemic drugs, fosravuconazole l-lysine ethanolate, posaconazole, and a tetrazole, luliconazole 5% nail solution, and device-based therapies, such as plasma therapy and adjunctive nail trephination to heighten topical penetration [6]. Therefore, the increase in treatment publications likely reflects relatively new onychomycosis drug approvals and drugs and devices under investigation.
Less than 1/5 of the highly cited onychomycosis articles were published in the last decade. However, 9/10 publications with highest average citations per year were published within the last 10 years. While using total citation count is an easily quantifiable measure of impact, there is an inherent bias toward older articles since longer lifespans allow for more citing opportunities [9]. Average citation count per year may be a better indicator of impact and considers age bias. Future bibliometric studies might benefit from including average citation per year as a variable. Moreover, it would be helpful if databases like SCOPUS included average citation per year as a metric to sort articles.
We also found that 42% of first authorship positions of top 100 onychomycosis publications were held by women, and articles by female first authors were published in journals with higher median IF than males. In a bibliometric analysis of top dermatology authors by h-index, female comprised 0% of authors in 1980–1989, which increased to 19% in 2010–2019 [10]. In another bibliometric analysis of 100 highly cited nail psoriasis publications, 32% of first authors were female [11]. Though it is unclear why there is a relatively greater percentage of female authors for onychomycosis publications, it demonstrates better representation of female authors compared to studies on other dermatologic topics. Still, gender disparities exist. A quantitative observational study demonstrated that while females comprise almost half of all US and Canada dermatologists, only 26.1% of faculty heads are females and the median publications for male versus female dermatology professors were 94.5 versus 15.5, which is nearly six times less than male professors [12]. Since research output is one measure of academic success, it is important to acknowledge persistent gender gaps and provide more support and opportunities for female dermatologists.
Limitations include only using the SCOPUS database, which may potentially exclude relevant articles. While we calculated average citations per year, by using total citation count as the ranking criteria to initially obtain the top 100 onychomycosis publications, there is intrinsic bias toward older articles.
Conclusion
To our knowledge, this is the first bibliometric analysis of the onychomycosis literature. We found an overall increase in articles discussing onychomycosis treatment over time, with the majority published in high IF journals. We also found that a relatively greater percentage of first authors were female compared to studies on other dermatologic topics. Our analysis invites reflection on bibliometric analyses. While total citation count remains a widely used measure of impact in bibliometric studies, average citation count per year may be a better indicator of impact and should be considered in future studies.
Statement of Ethics
Ethics approval was not required due to local and national guidelines. Informed consent was not required as there were no patients involved in this study.
Conflict of Interest Statement
Ms. Albucker has no relevant conflicts of interest to disclose. Dr. Lipner has served as a consultant for Ortho Dermatologics, Hoth Therapeutics, BelleTorus Corporation, and Moberg Pharmaceuticals.
Funding Sources
The authors did not receive any funding to complete this research.
Author Contributions
Ms. Albucker and Dr. Lipner both contributed to the conception, drafting, and revising of the work, as well as final approval of the version to be published, and agreed to be accountable for all parts of the work, ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Funding Statement
The authors did not receive any funding to complete this research.
Data Availability Statement
All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.


