Funding

No sources of funding were used to conduct this study or prepare this manuscript.

Conflict of interest

Tiago Torres has received honoraria for acting as a consultant and/or speaker for AbbVie, Almirall, Amgen, Arena Pharmaceuticals, Biocad, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Fresenius Kabi, Janssen, LEO Pharma, Eli Lilly, MSD, Mylan, and Novartis. Luis Puig has received honoraria for acting as a consultant and/or speaker for AbbVie, Almirall, Amgen, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Janssen, Leo-Pharma, Lilly, Novartis, Pfizer, Sandoz, Sanofi, and UCB. Ron Vender has received grants/research support from, and/or acted as a speaker/consultant for AbbVie, Amgen, Arcutis, Bausch-Health, BMS, Boehringer Ingelheim, Celgene, Centocor, Dermira, Dermavant, Galderma, GSK, Innovaderm, Janssen, Kabi-Care, Leo, Lilly, Takeda, Novartis, Merck, Palladin, Pfizer, Regeneron, Sandoz, Sanofi, Sun, UCB, and Viatris-Mylan. Jensen Yeung has been a speaker, consultant, and investigator for AbbVie, Allergan, Amgen, Astellas, Boehringer Ingelheim, Celgene, Centocor, Coherus, Dermira, Eli Lilly, Forward, Galderma, GSK, Janssen, Leo, Medimmune, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi Genzyme, Takeda, UCB, Valeant, and Xenon. José-Manuel Carrascosa has participated as a PI/SI, member of steering committees, advisor, and/or invited speaker for Celgene, Amgen, AbbVie, Almirall, Novartis, Leo-Pharma, Lilly, Sandoz, Mylan, Janssen, Boehringer Ingelheim, UCB, and BMS. Stefano Piaserico has been a consultant and/or speaker for AbbVie, Almirall, Amgen, Janssen, LEO Pharma, Eli Lilly, Merck Sharp & Dohme, Novartis, Pfizer, Sandoz, and UCB. Paolo Gisondi has received honoraria for acting as a consultant and/or speaker for AbbVie, Almirall, Amgen, Biogen, Bristol Myers Squibb, Celgene, Janssen, LEO Pharma, Eli Lilly, MSD, Novartis, Pierre Fabre, Sanofi, and UCB. Charles Lynde has been a speaker and/or consultant for AbbVie, Altius, Amgen, Aralez, Arcutis, Bausch Health, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Cipher, Dermavant, Devonian, Eli Lilly, Fresnius Kabi, Galderma, GSK, Innovaderm, Intega Skin, Janssen, Kyowa Kirin, La Roche Posay, LEO Pharma, L'Oreal, Medexus, MedX, Merck, Novartis, P&G, Pediapharm, Pfizer, Regeneron, Roche, Sanofi Genzyme, Sandoz, Sentrex, TEVA, Tribute, UCB, Valeant, Viatris, and Volo Health. Paulo Ferreira has received honoraria for acting as a consultant and/or speaker for AbbVie, Janssen, LEO Pharma, Eli-Lilly, Novartis, and Pfizer. Pedro Mendes-Bastos has received honoraria for acting as a consultant and/or speaker for AbbVie, Pfizer, Janssen, LEO Pharma, Novartis, Sanofi, Teva, Bayer, and L’Oreal. Esteban Dauden has been an advisory board member and consultant, participated in clinical trials, and received grants, research support, and honorarium for speaking from AbbVie/Abbott, Almirall, Amgen-Celgene, Janssen-Cilag, Leo Pharma, Novartis, Pfizer, MSD-Schering-Plough, Lilly, UCB, Bristol Myers, and Boehringer Ingelheim. Elena del Alcazar-Viladomiu has participated as an SI and/or invited speaker for AbbVie, Janssen, Novartis, Lilly, Leo Pharma, Almirall, Amgen, UCB, and Sanofi. Eva Vilarrasa Rull has received honoraria for acting as a consultant and/or speaker for AbbVie, Almirall, Boehringer, Celgene, Janssen, Leo Pharma, Eli Lilly, MSD, Novartis, Pfizer, and UCB. Mar Llamas-Velasco has received honoraria for acting as a consultant and/or speaker for AbbVie/Abbott, Almirall, Amgen-Celgene, Janssen-Cilag, Leo Pharma, Novartis, Pfizer, and Lilly. Jan Hugo has received honoraria for acting as a consultant/speaker for AbbVie, Amgen, and Novartis. Anna Balato has received honoraria for acting as speaker and consultant for Sanofi, AbbVie, and Eli Lilly. Marco Romanelli has been an advisory board member and consultant, received fees and speaker’s honoraria, or participated in clinical trials for AbbVie, Abiogen, Almirall, Lilly, Mundipharma, Novartis, Leo Pharma, Smith & Nephew, Urgo Medical, Hartman, and Sanofi. Francesca Prignano has served as an advisory board member and consultant, received fees and speaker's honoraria, or participated in clinical trials for AbbVie, Almirall, Leo Pharma, Lilly, Janssen, Novartis, Biogen, and Sanofi Genzyme. Spyridon Gkalpakiotis has received honoraria for acting as a consultant and/or speaker for AbbVie, Amgen, Eli Lilly, Novartis, Leo Pharma, and Janssen-Cilag. Curdin Conrad has served as a scientific adviser, clinical study investigator, and/or paid speaker for AbbVie, Actelion, Almirall, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Eli Lilly, Galderma, Incyte, Janssen, LEO Pharma, MSD, Novartis, Pfizer, Samsung, and UCB. Elizabeth Lazaridou has received honoraria for acting as a consultant and/or speaker for AbbVie, Eli Lilly-Galderma, Leo, Novartis, Janssen, UCB, Pfizer, Genesis Pharma, and Sanofi. Natalia Rompoti has received honoraria for lectures from Janssen, AbbVie, Genesis Pharma, Leo, Lilly Pharmaserve, Novartis, and UCB, and support for scientific congress attendance from AbbVie, Janssen, Leo, Lilly Pharmaserve, Novartis, and UCB. Marina Papoutsaki has received honoraria for advisory boards and lectures from Janssen, Leo Pharma, MSD, Genesis Pharma, Pfizer, Novartis, AbbVie, and UCB, and support as an investigator in clinical studies from AbbVie, Novartis, Leo Pharma, and Janssen. Miguel Nogueira has received honoraria for acting as a consultant/speaker for Abbvie and Leo Pharma. Andrea Chiricozzi has served as an advisory board member and consultant, received fees and speaker's honoraria, or participated in clinical trials for AbbVie, Almirall, Biogen, Fresenius Kabi, Leo Pharma, Lilly, Janssen, Novartis, Sanofi Genzyme, and UCB Pharma. Luiz Leite, Joana Valerio, Federico Pirro, Francesco Messina, Manfredo Bruni, Gaetano Licata, Federica Ricceri, Alessia Nidegger, Asfandyar Mufti, Athina-Ioanna Daponte, Laetitia Teixeira have no conflicts of interest to declare.

Ethics

The present study was conducted in accordance with the Declaration of Helsinki (initially published in 1964) on Ethical Principles for Medical Research Involving Human Subjects and after approval by the local ethical committees.

Consent to participate

Informed consent was waived due to the study’s retrospective design. Data were properly anonymized before the analysis.

Consent for publication

Not applicable.

Availability of data and materials

Not applicable.

Code availability

Not applicable.

Author contributions

TT and AC contributed to the study conception and design. TT, LP, LT, MN and AC conducted the statistical analyses on the data. All authors participated in data collection and interpretation of the data, provided critical feedback on the manuscript, approved the final manuscript for submission, and were accountable for the accuracy and integrity of the article.