Procedures performed during neurosurgery residency in Europe
Authors: Stienen Martin N. , Freyschlag Christian F. , Schaller Karl , Meling Torstein ,   for the EANS Young Neurosurgeons and EANS Training Committee, Al-Amin Amir , Al-Mahfoudh Rafid , Amelot Aymeric , Arvidsson Lisa , Athanasiou Alkinoos , Avellan Cecilia I. A. , Bauchet Luc , Berilazic Luka , Bolger Ciaran , Bourdillon Pierre , Boviatsis Stathis , Bozinov Oliver , Branco Pedro , Braunsdorf Werner , Cahill Julian , Clusmann Hans , Conrad Jens , Cordier Dominik , Cristino Nuno , Djilvesi Djula , Duerinck Johnny , Dumot Chloé , Durak Mehmet Akif , Eisenring Christian V. , Esposito Giuseppe , Finiels Pierre-Jacques , Flaskas Theofanis , Freyschlag Christian F. , Fuentes Stéphane , Ganau Mario , Georgiadis Iordanis , Georgiopoulos Miltiadis , Giakoumettis Dimitrios , Gilis Nathalie , Gradil Catia , Grau Stefan J. , Grin Andrey , Hadjigeorgiou Georgios , Halatsch Marc-Eric , Hecht Nils , Holling Markus , Ilic Rosanda , Iken Linda , Santos Nazaret Infante , Jacquesson Timothee , Jalloh Ibrahim , Jelaca Bojan , Kaestner Stefanie , Kalasauskas Darius , Kaliyev Assylbek , Kleiber Jean-Charles , Konczalla Juergen , Kothbauer Karl F. , Kovacevic Vojin , Krajcinovic Nenad , Krieg Sandro M. , Kämäräinen Olli-Pekka , Lapcic Mirko , Lapras Christophe , Ljungqvist Johan , Lo William B. , Lubrano Vincent , Majovsky Martin , Manet Romain , Marchi Francesco , Medetov Yerkin , Meling Torstein R. , Melloni Ilaria , Melot Anthony , Mertens Patrick , Metcalfe Stephen , Moerkve Svein H. , Mora Alexa Ruiz , Musabelliu Erion , Naushahi Mohammad J. , Nurzhan Aitimbetov , Omerhodzic Ibrahim , Paldor Iddo , Pallud Johan , Papanastassiou Vakis , Papic Vladimir , Paschalis Thanasis , Payer Michael , Peerdeman Saskia M. , Peruzzi Philippe , Segerlind Jenny Pettersson , Posti Jussi P. , Proust Francois , Regli Luca , Rinne Jaako , Roche Pierre-Hugues , Rocka Saulius , Rotermund Roman , Rutherford Scott A. , Rätsep Tönu , Rüter Andreas , Saarenpää Ilkka M. , Samanci Mustafa Y. , Samardzic Marko , Sampron Nicolas , Sandvik Ulrika , Scerrati Alba , Schaller Karl , Schneider Michel , Schul David B. , Sengul Goksin , Simon Emile , Sinha Saurabh , Solheim Ole , Spatola Giorgio , Spektor Sergey , Stienen Martin N. , Sundblom Jimmy , Syrmos Nikolaos C. , Teo Mario , Thomson Simon , Tonchev Nikolay , Tosic Lazar , Vandertop William P. , von der Brelie Christian , Vuk Aleksic , Walkden James , Wendel Christopher , Yaqout Mohammed , Yusupova Madina , Zollino Gianluca 
Published: August 2020

Abstract
Background
In a previous article (10.1007/s00701-019-03888-3), preliminary results of a survey, aiming to shed light on the number of surgical procedures performed and assisted during neurosurgery residency in Europe were reported. We here present the final results and extend the analyses.

Methods
Board-certified neurosurgeons of European Association of Neurosurgical Societies (EANS) member countries were asked to review their residency case logs and participate in a 31-question electronic survey (SurveyMonkey Inc., San Mateo, CA). The responses received between April 25, 2018, and April 25, 2020, were considered. We excluded responses that were incomplete, from non-EANS member countries, or from respondents that have not yet completed their residency.

Results
Of 430 responses, 168 were considered for analysis after checking in- and exclusion criteria. Survey responders had a mean age of 42.7 ± 8.8 years, and 88.8% were male. Responses mainly came from surgeons employed at university/teaching hospitals (85.1%) in Germany (22.0%), France (12.5%), the United Kingdom (UK; 8.3%), Switzerland (7.7%), and Greece (7.1%). Most responders graduated in the years between 2011 and 2019 (57.7%). Thirty-eight responders (22.6%) graduated before and 130 responders (77.4%) after the European WTD 2003/88/EC came into effect. The mean number of surgical procedures performed independently, supervised or assisted throughout residency was 540 (95% CI 424–657), 482 (95% CI 398–568), and 579 (95% CI 441–717), respectively. Detailed numbers for cranial, spinal, adult, and pediatric subgroups are presented in the article. There was an annual decrease of about 33 cases in total caseload between 1976 and 2019 (coeff. − 33, 95% CI − 62 to − 4, p = 0.025). Variables associated with lesser total caseload during residency were training abroad (1210 vs. 1747, p = 0.083) and female sex by trend (947 vs. 1671, p = 0.111), whereas case numbers were comparable across the EANS countries (p = 0.443).

Conclusion
The final results of this survey largely confirm the previously reported numbers. They provide an opportunity for current trainees to compare their own case logs with. Again, we confirm a significant decline in surgical exposure during training between 1976 and 2019. In addition, the current analysis reveals that female sex and training abroad may be variables associated with lesser case numbers during residency.