Publication productivity of neurosurgeons in Great Britain and Ireland

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OBJECT

Bibliometrics are the methods used to quantitatively analyze scientific literature. In this study, bibliometrics were used to quantify the scientific output of neurosurgical departments throughout Great Britain and Ireland.

METHODS

A list of neurosurgical departments was obtained from the Society of British Neurological Surgeons website. Individual departments were contacted for an up-to-date list of consultant (attending) neurosurgeons practicing in these departments. Scopus was used to determine the h-index and m-quotient for each neurosurgeon. Indices were measured by surgeon and by departmental mean and total. Additional information was collected about the surgeon's sex, title, listed superspecialties, higher research degrees, and year of medical qualification.

RESULTS

Data were analyzed for 315 neurosurgeons (25 female). The median h-index and m-quotient were 6.00 and 0.41, respectively. These were significantly higher for professors (h-index 21.50; m-quotient 0.71) and for those with an additional MD or PhD (11.0; 0.57). There was no significant difference in h-index, m-quotient, or higher research degrees between the sexes. However, none of the 16 British neurosurgery professors were female. Neurosurgeons who specialized in functional/epilepsy surgery ranked highest in terms of publication productivity. The 5 top-scoring departments were those in Addenbrooke's Hospital, Cambridge; St. George's Hospital, London; Great Ormond Street Hospital, London; National Hospital for Neurology and Neurosurgery, Queen Square, London; and John Radcliffe Hospital, Oxford.

CONCLUSIONS

The h-index is a useful bibliometric marker, particularly when comparing between studies and individuals. The m-quotient reduces bias toward established researchers. British academic neurosurgeons face considerable challenges, and women remain underrepresented in both clinical and academic neurosurgery in Britain and Ireland.

ABBREVIATIONSNHNN = National Hospital for Neurology and Neurosurgery; NIH = National Institutes of Health; SBNS = Society of British Neurological Surgeons.

Abstract

OBJECT

Bibliometrics are the methods used to quantitatively analyze scientific literature. In this study, bibliometrics were used to quantify the scientific output of neurosurgical departments throughout Great Britain and Ireland.

METHODS

A list of neurosurgical departments was obtained from the Society of British Neurological Surgeons website. Individual departments were contacted for an up-to-date list of consultant (attending) neurosurgeons practicing in these departments. Scopus was used to determine the h-index and m-quotient for each neurosurgeon. Indices were measured by surgeon and by departmental mean and total. Additional information was collected about the surgeon's sex, title, listed superspecialties, higher research degrees, and year of medical qualification.

RESULTS

Data were analyzed for 315 neurosurgeons (25 female). The median h-index and m-quotient were 6.00 and 0.41, respectively. These were significantly higher for professors (h-index 21.50; m-quotient 0.71) and for those with an additional MD or PhD (11.0; 0.57). There was no significant difference in h-index, m-quotient, or higher research degrees between the sexes. However, none of the 16 British neurosurgery professors were female. Neurosurgeons who specialized in functional/epilepsy surgery ranked highest in terms of publication productivity. The 5 top-scoring departments were those in Addenbrooke's Hospital, Cambridge; St. George's Hospital, London; Great Ormond Street Hospital, London; National Hospital for Neurology and Neurosurgery, Queen Square, London; and John Radcliffe Hospital, Oxford.

CONCLUSIONS

The h-index is a useful bibliometric marker, particularly when comparing between studies and individuals. The m-quotient reduces bias toward established researchers. British academic neurosurgeons face considerable challenges, and women remain underrepresented in both clinical and academic neurosurgery in Britain and Ireland.

Academic institutions are increasingly interested in methods of determining and ranking research productivity.14 One such method is the h-index, which was introduced by Hirsch in 2005 as a method of counting the most highly cited papers by a particular author.10 While there are a number of other methods, the h-index is widely used and, despite its limitations, is emerging as one of the more relevant markers of academic productivity, including within the field of neurosurgery.13,14 In the US, the hindex has a significant correlation with academic rank,12,19 research funding,21 and salary, even after controlling for rank.7 Shortcomings of the h-index include bias in favor of senior researchers by neglecting to take into account the number of years since first publication.13

We sought to extend the recent research of a neurosurgical group in the US by examining the status of neurosurgical research in Great Britain and Ireland (Fig. 1).14 Bibliometric tools selected were the h-index as well as the m-quotient,10 which is the h-index divided by the number of years since first publication. The latter tool mitigates some of the inherent bias of the h-index toward more seasoned researchers. The relationship between productivity and author sex, research degrees, and academic rank was also examined.

FIG. 1.
FIG. 1.

Map of Great Britain and Ireland. Great Britain (or Britain) is the geographical term given to the island that contains England, Scotland, and Wales. Ireland is the geographical term given to the island that contains Northern Ireland and the Republic of Ireland. The United Kingdom (UK) consists of England, Scotland, Wales, and Northern Ireland.

Methods

Consultants and Demographics

A list of neurosurgical departments in Great Britain and Ireland was obtained from the website of the Society of British Neurological Surgeons (SBNS). During January and February of 2014, each department was contacted by telephone for an up-to-date list of practicing consultant (attending) neurosurgeons. Consultant superspecialty, higher research degrees awarded (MD or PhD in addition to basic medical degree), and academic status were taken from departmental websites when this information was available and from a broader Internet search when the information was not available on the department site. Year of qualification was obtained from the UK General Medical Council List of Registered Medical Practitioners (http://www.gmc-uk.org/doctors/register/LRMP.asp) and from the Irish Medical Council Register (http://www.medicalcouncil.ie/Public-Information/Check-the-Register/).

Superspecialties were grouped as functional/epilepsy, radiosurgery, vascular, neurooncology/skull base, pediatric, spine, general, or peripheral nerve. When more than one superspecialty was listed, only one was chosen according to a weighting system: pediatric > functional/epilepsy, radiosurgery, peripheral nerve > vascular > neurooncology, general, spine. Thus, if a surgeon listed both peripheral nerve and spine surgery as specialties, he or she was coded as a peripheral nerve neurosurgeon. This system was chosen based on the number of specialists in each category: for example, far fewer neurosurgeons list peripheral nerve surgery as a specialty as compared with spinal surgery.

In Britain and Ireland the basic medical degree awarded is Bachelor of Medicine, Bachelor of Surgery (MBBS). A “higher research degree” is one that is awarded after a period of research that results in a thesis and is successfully defended during a viva voce examination. A 2-year period of research normally leads to an MD; a PhD is usually awarded after a minimum research period of 3 years.

Bibliometrics

Scopus (www.scopus.com) was used to identify authors and to obtain h-indices. The Scopus “author search” function uses an algorithm to differentiate between authors with common names, although this sometimes requires some manual correction. The h-index can be determined by ranking an individual's papers according to the number of citations that those papers have received. The h-index is taken to be when an individual has at least h papers with ≥ h citations; that is, an individual with 6 papers that have 6 or more citations has an h-index of 6. Scopus provides an automated h-index for all papers after 1996, so the manual method mentioned above was used for all individuals with earlier papers. The m-quotient was also derived by dividing the h-index by the number of years since the publication of an author's first paper.

Statistical Analysis

Nonparametric tests were used to determine differences in h-indices and m-quotients between groups (Mann-Whitney U-test for author sex, rank, higher research degree, and year of first publication; Kruskal-Wallis test for superspecialty). Significance was set at p < 0.05. Values are expressed as the mean ± standard deviation or the median.

Results

Data were analyzed for the 315 neurosurgeons (25 female) working in neurosurgical departments across Great Britain and Ireland, as listed by the SBNS website in January 2014. There was significant overlap in neurosurgical consultant staff in the following departments: 1) Queen Elizabeth Hospital Birmingham and the Birmingham Children's Hospital and 2) Beaumont Hospital in Dublin and the Temple Street Children's University Hospital in Ireland. One additional consultant had two affiliations and, for the purposes of this analysis, was listed as a member of the smaller department only. In addition, the neurosurgical department at the Royal Free Hospital recently closed, and consultant staff joined the Victor Horsley Department of Neurosurgery at the National Hospital for Neurology and Neurosurgery (NHNN), Queen Square, London. Combining these departments reduced the initial list of 37 departments to 34 for this analysis.

Author Sex, Rank, and Higher Research Degrees

Professors had significantly higher h-indices (median 21.50 vs 6.00, p < 0.001) and m-quotients (0.71 vs 0.40, p < 0.001) than surgeons without this rank (Table 1). Neurosurgeons who held an MD or PhD also had significantly higher h-indices (11.00 vs 5.00, p < 0.001) and m-quotients (0.57 vs 0.35, p < 0.001) than those without these degrees. There was no significant difference in h-index or m-quotient between the sexes (p > 0.05). Moreover, chi-square tests revealed no significant differences between the sexes in the possession of an MD and/or PhD. However, none of the 16 professors in neurosurgery were female. Professors were significantly more likely to hold a higher research degree than neurosurgeons without this title (81.3% vs 25.8%, p < 0.001, Fisher exact test).

TABLE 1

Academic output, as measured by the h-index and m-quotient, stratified by author sex, rank, and degree*

CharacteristicNo.h-Indexm-QuotientYear of First Publication
Mean (SD)Medianp ValueMean (SD)Medianp ValueMean (SD)p Value
Total3158.15 (7.49)6.000.49 (0.37)0.411997 (8)
Sex
 Male2908.35 (7.70)6.000.230.49 (0.38)0.400.751997 (8)0.01
 Female255.88 (3.71)6.000.47 (0.28)0.502001 (6)
Rank
 Mr/Ms2997.31 (6.15)6.00<0.0010.46 (0.34)0.40<0.0011998 (8)<0.001
 Professor1623.94 (11.99)21.500.98 (0.59)0.711988 (7)
MD or PhD
 No2256.75 (6.44)5.00<0.0010.41 (0.29)0.35<0.0011998 (8)0.11
 Yes9011.66 (8.73)11.000.68 (0.47)0.571996 (8)
PhD
 No2787.60 (6.86)6.000.0030.46 (0.34)0.400.0011997 (8)0.87
 Yes3712.27 (10.38)12.000.72 (0.52)0.591997 (9)

SD = standard deviation.

In Britain and Ireland, the basic medical degree awarded is MBBS. Both MD and PhD are higher research degrees.

Boldface type indicates significance.

Superspecialty

There were significant differences in the h-index (p = 0.002, Kruskal-Wallis) and m-quotient (p = 0.018) across the neurosurgical superspecialties, with functional/epilepsy and radiosurgery scoring the highest for both variables (Table 2). Neurosurgeons who specialized in one of these top two categories had significantly higher h-indices and m-quotients than those who did not practice in either category (median h-index 11.0 vs 6.0, median m-quotient 0.54 vs 0.38, p < 0.001, Mann-Whitney U-test).

TABLE 2

Academic output, as measured by the h-index and m-quotient, stratified by surgical superspecialty

SuperspecialtyRankMean h-Index (SD)Mean m-Quotient (SD)No. of Consultants
Functional/Epilepsy112.00 (10.11)0.70 (0.53)31
Radiosurgery210.95 (6.08)0.62 (0.34)22
Vascular39.29 (10.21)0.48 (0.43)51
Neurooncology/skull base47.66 (5.04)0.44 (0.28)67
Pediatrics57.57 (6.76)0.51 (0.34)54
Spine66.29 (5.33)0.39 (0.21)56
General76.21 (8.50)0.47 (0.52)24
Peripheral nerve85.80 (4.32)0.33 (0.10)10

Department

Average departmental h-indices and m-quotients were computed, and each department was ranked according to mean h-index (Table 3 and Figs. 2 and 3). The top 5 departments were Addenbrooke's Hospital in Cambridge; St. George's Hospital, Great Ormond Street Hospital, and the NHNN, Queen Square, in London; and the John Radcliffe Hospital in Oxford.

TABLE 3

Academic output, as measured by the h-index and m-quotient, stratified by department

Hospital DepartmentRankh-IndexMean m-QuotientNo. of NeurosurgeonsSum of h-Indices
MeanMedian
Addenbrooke's, Cambridge*117.3814.000.9713226
St George's, London*216.8811.000.778135
Great Ormond Street, London*316.6013.001.12583
NHNN, Queen Square, London*413.4411.000.6916215
John Radcliffe, Oxford*511.438.500.6514160
Alder Hey, Liverpool*610.257.000.73441
Royal Victoria Infirmary, Newcastle*79.505.000.471095
Frenchay Hospital, Bristol*89.386.000.5213122
Cork University, Cork98.6710.000.31326
South West Neurosurgery, Plymouth*108.389.500.38867
King's College, London*118.186.000.491190
Walton Centre, Liverpool*128.076.000.5415121
Charing Cross, London*137.875.500.57863
Queen Elizabeth & Birmingham Children's, Birmingham*147.676.000.4915115
Queen's Medical Centre, Nottingham*157.306.000.421073
Princess Royal Hospital, West Sussex*167.257.500.33429
Royal Hallamshire, Sheffield*177.156.000.581393
Western General, Edinburgh187.007.000.50963
Ninewells Hospital, Dundee197.004.500.39428
General Infirmary, Leeds*206.506.500.411278
Queen's Hospital, Romford*216.385.500.38851
Hope Hospital, Salford*226.285.000.4118113
Beaumont & Children's, Dublin236.096.000.351167
Barts and Royal London, London*246.006.500.32636
Southern General, Glasgow255.924.500.381271
University Hospital Wales, Cardiff265.674.000.38951
University Hospital Coventry*275.505.500.34633
Royal Victoria Hospital, Belfast§285.004.000.34840
Royal Preston, Preston*294.893.000.24944
Wessex Neurological Centre, Southampton*304.865.000.27734
North Staffordshire, Staffordshire*314.804.000.36524
James Cook University, Middlesbrough*324.624.000.23837
Hull Royal Infirmary, Hull*333.443.000.31931
Aberdeen Royal Infirmary, Aberdeen343.252.500.37413

England.

Scotland.

Wales.

Northern Ireland.

Republic of Ireland.

FIG. 2.
FIG. 2.

Box plot of publication productivity of neurosurgical departments in Great Britain and Ireland: h-index. Stars indicate individual indices that are more than 1.5 interquartile ranges away from their departmental interquartile range. QE & Birm = Queen Elizabeth & Birmingham.

FIG. 3.
FIG. 3.

Box plot of publication productivity of neurosurgical departments in Great Britain and Ireland: m-quotient. Stars indicate individual indices that are more than 1.5 interquartile ranges above the upper quartile for their department.

Discussion

Publication productivity in Great Britain and Ireland was higher for professors and those with an MD or PhD in addition to their basic medical degrees. A larger proportion of professors held an MD or PhD; one-quarter of the other neurosurgeons held one or the other of these degrees. Women account for 8% of neurosurgeons in Great Britain and Ireland. Although there was no significant difference in h-index or m-quotient between the sexes, none of the 16 professors in neurosurgery were female.

It is worth comparing the results presented here with those recently reported from the US. In the US, neurosurgeons with a PhD degree were significantly more likely to hold an academic appointment and to receive National Institutes of Health (NIH) funding.3 Nearly 20% of neurosurgery graduates and residents in high-ranking (by hindex) departments in the US held PhDs in addition to a baseline medical degree, a proportion that has been gradually increasing over time.4 Multiple studies have shown a positive relationship between rank and h-index;1,11,13–15,19 to our knowledge this is the first study to examine whether possessing a higher research degree is related to the publication productivity of neurosurgeons. A North American study discussed a “PhD effect” within neurosurgical departments,17 but it included papers by non-neurosurgical research staff and clinical affiliates within the departmental output and did not directly compare the h-indices of neurosurgeons with and without PhDs.

The median British h-index (6.0) is lower than the data published about the US (11.0).14 There are a number of possible explanations for this disparity. Data in the US study were collected from neurosurgical services with a neurosurgery resident training program—and thus included practices dedicated to training and academia with the exclusion of those dedicated primarily to the provision of service—whereas all neurosurgical centers in Britain and Ireland were included in the present study. Moreover, the number of neurosurgeons in the UK is one of the lowest per capita in the developed world, with 1 fully trained neurosurgeon per 254,063 people compared with 1 per 85,542 people in the US (2008 data).4,18 The pressure of clinical work in Britain and Ireland is likely to have a negative impact on collective academic output.

Disparity in funding opportunities will affect neurosurgical academic productivity. Unfortunately, systematic data on research funding awarded to British and Irish neurosurgeons are not readily available. However, health care and health care research funding comparisons between the UK and the US are expedient indicators. In 2010, the total health care expenditure per capita was $8233 in the US and $3433 in the UK.23 Similarly, while the amount invested in medical research by the US NIH in 2013 was around $30.1 billion,6 investment over the same period by the equivalent body in the UK, the National Institute for Health Research (NIHR), was around $1.6 billion.16 Clearly, US neurosurgeons enjoy substantially greater financial opportunities. Indeed, the academic productivity of neurosurgeons in Britain and Ireland is likely to represent very good value for the money.

Similar proportions of female neurosurgeons work in Britain and Ireland, and the US (8% vs 7%).14 Although there were no significant differences in academic output between the sexes in Britain and Ireland, a significant difference is seen in neurosurgical h-indices between the sexes in the US.14 This difference was lost after correction for academic rank, implying that there are more male than female professors of neurosurgery in the US. None of the professors of neurosurgery in Britain or Ireland are female. Despite the pioneering work of a number of females in neurosurgery,9 women remain underrepresented in clinical and academic neurosurgery, both in the British Isles and in the US.14,20,22

Neurosurgery in general, and academic neurosurgery in particular, requires an exceptional skill set. It must attract highly gifted, compassionate, and capable individuals. Clearly, active measures are required to inspire and support doctors of both sexes to consider a career in clinical and academic neurosurgery. The relative lack of women in neurosurgery has been attributed to a number of factors, including preconceptions about the role, lack of female role models, role strain, lack of academic advancement, discrimination, and harassment.2,20,22 Numerous strategies have been proposed to boost the proportion of female neurosurgeons in clinical and academic practice. Mentoring is important in the development of any career and has been shown to increase job-related well-being, self-esteem, and self-efficacy.6 Diana Beck (1902–1956), widely recognized as the world's first female neurosurgeon, was mentored by Sir Hugh Cairns in Oxford, England.8,20 The group “Women in Neurosurgery” has developed a mentoring program for female neurosurgeons in the US.3 A similar initiative should be considered in Britain and Ireland.

Neurosurgical research in Britain and Ireland would also benefit from a centralized register that summarizes ongoing neurosurgical research projects and grants awarded to neurosurgeons and/or neurosurgical departments. Such an overview of neurosurgical research would prevent duplication of work by different departments and may foster collaboration between departments with similar interests. Moreover, it would highlight areas of weakness in neurosurgical research that might benefit from targeted funding and would provide aspiring neurosurgical trainees with a comprehensive list of research opportunities across the region.

The h-index is widely acknowledged to favor senior researchers, as they have had more time to publish and for their publications to be cited.13 The m-quotient tends to correct for this bias by taking into account the number of years since first publication. While there was a significant difference in the h-index between the sexes in the US, there was no significant sex difference in Britain and no difference between m-quotients in either location.14 This, together with our finding of a significantly later date of first publication for female neurosurgeons in Britain and Ireland, may suggest that a historical sex bias in the h-index is decreasing over time.

Any work of this nature will have limitations. Consultants in locum posts were not included, and it is assumed that individual departments provided a comprehensive list of current staff when contacted. Most neurosurgeons in Britain and Ireland practice in more than one superspecialty. The data presented in Table 2 do not take this into account, and the weighting system used to assign superspecialties is biased toward pediatric, functional, epilepsy, radiosurgery, and peripheral nerve surgery over vascular, neurooncology, general neurosurgery, and spine. Nevertheless, despite these and other possible shortcomings, the presented data provide a “snapshot” of academic productivity across neurosurgical departments in Britain and Ireland. Individual neurosurgeons may now gauge their own productivity with that of their peers, both within their department and across departments. Comparison between departments and countries may also encourage healthy competition within neurosurgical academia.

We used Scopus to calculate the h-index, as it is thought to provide more accurate results for individual analysis. Comparing indices obtained with other calculation tools may not be appropriate; for example, Google Scholar may overestimate the h-index as it also includes conference proceedings, white papers, and books.14

The h-index itself has a number of limitations. Hirsch acknowledges that a single number can only provide a rough approximation of the multifaceted profile, although it does provide a useful, objective yardstick.10 Ranking departments by the sum of individual h-indices favors departments with more faculty members. Although it is a good marker of overall departmental impact, it may not necessarily be an accurate marker of the academic quality of staff. Conversely, the mean h-index may be misleading when dealing with nonparametric data and can also be unduly influenced by the presence of one or two outstanding individuals. Therefore, the median h-index is a more relevant statistic. Marital change in surname affecting citation accuracy may lead to a possible bias against women in bibliometrics. This factor was identified and corrected for in this study but may be missed in studies with larger sample sizes.

Conclusions

Bibliometric indices are useful when comparing academic neurosurgeons and departments but should be interpreted with caution. The h-index is the most widely used metric of academic productivity and is useful when comparing studies and assessing the overall academic impact of an individual. However, the m-quotient may be a better marker of current productivity, as it reduces the bias toward older and established researchers. Such studies create a benchmark for individual academic neurosurgeons and allow comparisons between countries for which differences in clinical and academic infrastructure may have an impact on academic productivity. Women remain underrepresented in both clinical and academic neurosurgery in Great Britain and Ireland. A dedicated mentoring program may reduce this sex disparity.

Author Contributions

Conception and design: Zrinzo, Wilkes. Acquisition of data: Zrinzo, Wilkes, Akram, Hyam. Analysis and interpretation of data: Zrinzo, Wilkes, Kitchen, Hariz. Drafting the article: Zrinzo, Wilkes. Critically revising the article: all authors. Reviewed submitted version of manuscript: all authors. Approved the final version of the manuscript on behalf of all authors: Zrinzo. Statistical analysis: Wilkes. Administrative/technical/material support: Zrinzo. Study supervision: Zrinzo.

References

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    Benzil DLAbosch AGermano IGilmer HMaraire JNMuraszko K: The future of neurosurgery: a white paper on the recruitment and retention of women in neurosurgery. J Neurosurg 109:3783862008

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    Choi BDDeLong MRDeLong DMFriedman AHSampson JH: Impact of PhD training on scholarship in a neurosurgical career. J Neurosurg 120:7307352014

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    Couldwell WTSeaver MJ: A global experience: neurosurgeons analyze their practice environments. AANS Neurosurgeon 17:35102008

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    Department of Health and Human Services National Institutes of Health: Fiscal Year 2014 Budget Request. National Institutes of Health (http://www.nih.gov/about/director/budgetrequest/fy2014testimony.htm) [Accessed November 29 2014]

  • 6

    Dutta RHawkes SLKuipers EGuest DFear NTIversen AC: One year outcomes of a mentoring scheme for female academics: a pilot study at the Institute of Psychiatry, King's College London. BMC Med Educ 11:132011

  • 7

    Fijalkowski NZheng LLHenderson MTMoshfeghi AAMaltenfort MMoshfeghi DM: Academic productivity and its relationship to physician salaries in the University of California Healthcare System. South Med J 106:4154212013

  • 8

    Gilkes CE: An account of the life and achievements of Miss Diana Beck, neurosurgeon (1902–1956). Neurosurgery 62:7387422008

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    Hariz GMRehncrona SBlomstedt PLimousin PHamberg KHariz M: Women pioneers in basal ganglia surgery. Parkinsonism Relat Disord 20:1371412014

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    Hirsch JE: An index to quantify an individual's scientific research output. Proc Natl Acad Sci U S A 102:16569165722005

  • 11

    Kalra RRKestle JRW: An assessment of academic productivity in pediatric neurosurgery. J Neurosurg Pediatr 12:2622652013

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    Khan NThompson CJChoudhri AFBoop FAKlimo P Jr: Part I: The application of the h-index to groups of individuals and departments in academic neurosurgery. World Neurosurg 80:759765.e32013

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    Khan NRThompson CJTaylor DRGabrick KSChoudhri AFBoop FR: Part II: Should the h-index be modified? An analysis of the m-quotient, contemporary h-index, authorship value, and impact factor. World Neurosurg 80:7667742013

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    Khan NRThompson CJTaylor DRVenable GTWham RMMichael LM II: An analysis of publication productivity for 1225 academic neurosurgeons and 99 departments in the United States. J Neurosurg 120:7467552014

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    Lee JKraus KLCouldwell WT: Use of the h index in neurosurgery. Clinical article. J Neurosurg 111:3873922009

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    National Institute for Health Research Annual Report 2012/2013: National Institute for Health Research (UK) (http://viewer.zmags.com/publication/26f799ac#/26f799ac/1) [Accessed November 29 2014]

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    Ponce FALozano AM: Academic impact and rankings of American and Canadian neurosurgical departments as assessed using the h index. J Neurosurg 113:4474572010

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    Powell M: Practicing neurosurgery in United Kingdom. AANS Neurosurgeon 17:318192008

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    Spearman CMQuigley MJQuigley MRWilberger JE: Survey of the h index for all of academic neurosurgery: another power-law phenomenon?. J Neurosurg 113:9299332010

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    Spetzler RF: Progress of women in neurosurgery. Asian J Neurosurg 6:6122011

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    Venable GTKhan NRTaylor DRThompson CJMichael LMKlimo P Jr: A correlation between National Institutes of Health funding and bibliometrics in neurosurgery. World Neurosurg 81:4684722014

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    Woodrow SIGilmer-Hill HRutka JT: The neurosurgical workforce in North America: a critical review of gender issues. Neurosurgery 59:7497582006

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    World Health Organization: World Health Statistics 2013: A Wealth of Information on Global Public Health GenevaWorld Health Organization2013. (http://apps.who.int/iris/bitstream/10665/82058/1/WHO_HIS_HSI_13.1_eng.pdf?ua=1&ua=1) [Accessed November 29 2014]

If the inline PDF is not rendering correctly, you can download the PDF file here.

Article Information

Correspondence Ludvic Zrinzo, Unit of Functional Neurosurgery, Box 146, Institute of Neurology and National Hospital for Neurology and Neurosurgery, 33 Queen Square, London WC1N 3BG, United Kingdom. email: l.zrinzo@ucl.ac.uk.

INCLUDE WHEN CITING Published online January 23, 2015; DOI: 10.3171/2014.11.JNS14856.

DISCLOSURE The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. Drs. Zrinzo and Hariz occasionally receive honoraria for invited talks from Medtronic and St. Jude. This work was undertaken at University College London (UCL)/UCL Hospitals and was partly funded by the Department of Health National Institute of Health Research Biomedical Research Centres funding scheme. The Unit of Functional Neurosurgery, UCL Institute of Neurology, Queen Square, London, is supported by the Parkinson's Appeal and the Sainsbury Monument Trust.

© AANS, except where prohibited by US copyright law.

Headings

Figures

  • View in gallery

    Map of Great Britain and Ireland. Great Britain (or Britain) is the geographical term given to the island that contains England, Scotland, and Wales. Ireland is the geographical term given to the island that contains Northern Ireland and the Republic of Ireland. The United Kingdom (UK) consists of England, Scotland, Wales, and Northern Ireland.

  • View in gallery

    Box plot of publication productivity of neurosurgical departments in Great Britain and Ireland: h-index. Stars indicate individual indices that are more than 1.5 interquartile ranges away from their departmental interquartile range. QE & Birm = Queen Elizabeth & Birmingham.

  • View in gallery

    Box plot of publication productivity of neurosurgical departments in Great Britain and Ireland: m-quotient. Stars indicate individual indices that are more than 1.5 interquartile ranges above the upper quartile for their department.

References

1

Agarwal NClark SSvider PFCouldwell WTEloy JALiu JK: Impact of fellowship training on research productivity in academic neurological surgery. World Neurosurg 80:7387442013

2

Benzil DLAbosch AGermano IGilmer HMaraire JNMuraszko K: The future of neurosurgery: a white paper on the recruitment and retention of women in neurosurgery. J Neurosurg 109:3783862008

3

Choi BDDeLong MRDeLong DMFriedman AHSampson JH: Impact of PhD training on scholarship in a neurosurgical career. J Neurosurg 120:7307352014

4

Couldwell WTSeaver MJ: A global experience: neurosurgeons analyze their practice environments. AANS Neurosurgeon 17:35102008

5

Department of Health and Human Services National Institutes of Health: Fiscal Year 2014 Budget Request. National Institutes of Health (http://www.nih.gov/about/director/budgetrequest/fy2014testimony.htm) [Accessed November 29 2014]

6

Dutta RHawkes SLKuipers EGuest DFear NTIversen AC: One year outcomes of a mentoring scheme for female academics: a pilot study at the Institute of Psychiatry, King's College London. BMC Med Educ 11:132011

7

Fijalkowski NZheng LLHenderson MTMoshfeghi AAMaltenfort MMoshfeghi DM: Academic productivity and its relationship to physician salaries in the University of California Healthcare System. South Med J 106:4154212013

8

Gilkes CE: An account of the life and achievements of Miss Diana Beck, neurosurgeon (1902–1956). Neurosurgery 62:7387422008

9

Hariz GMRehncrona SBlomstedt PLimousin PHamberg KHariz M: Women pioneers in basal ganglia surgery. Parkinsonism Relat Disord 20:1371412014

10

Hirsch JE: An index to quantify an individual's scientific research output. Proc Natl Acad Sci U S A 102:16569165722005

11

Kalra RRKestle JRW: An assessment of academic productivity in pediatric neurosurgery. J Neurosurg Pediatr 12:2622652013

12

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