{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T04:10:04Z","timestamp":1779423004635,"version":"3.53.1"},"reference-count":32,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Justus-Liebig-Universit\u00e4t Gie\u00dfen"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Speleotherapy (underground climate therapy) is a non-pharmacological intervention for chronic respiratory diseases. This randomized controlled trial investigated whether a 3-week speleotherapy course (6 sessions, 2 h\/week) improves respiratory outcomes in patients on standard background therapy with asthma, COPD, or Long COVID, and whether it affects blood CO\n                    <jats:sub>2<\/jats:sub>\n                    levels. The control group did not receive speleotherapy but continued their standard therapy. A total of 208 patients (asthma: n\u2009=\u2009107; COPD: n\u2009=\u200959; Long COVID: n\u2009=\u200942) were enrolled across nine centers in Germany, Austria, and Italy. Assessments were conducted pre-intervention (T1), post-intervention (T2), and at 3-month follow-up (T3). Outcome measures included airway inflammation (FeNO), pulmonary function parameters (FVC% predicted values, FEV\u2081% predicted values, FEV\u2081\/FVC, PEF% predicted values), and respiratory muscle strength (MIP and MEP in absolute values). In addition the following validated questionnaires were administered: Asthma Control Test (ACT), Asthma Quality of Life Questionnaire (AQLQ), COPD Assessment Test (CAT), St. George\u2019s Respiratory Questionnaire (SGRQ), Nijmegen Questionnaire (NQ), and Fatigue Assessment Scale (FAS), along with the Long COVID questionnaire from the Median Clinic Group. CO\n                    <jats:sub>2<\/jats:sub>\n                    levels were assessed via capillary blood (SpCO\n                    <jats:sub>2<\/jats:sub>\n                    ) and end-tidal CO\n                    <jats:sub>2<\/jats:sub>\n                    (PetCO\n                    <jats:sub>2<\/jats:sub>\n                    ). Between-group comparisons used the Mann\u2013Whitney U test; within-group changes were assessed with the Wilcoxon signed-rank test (Bonferroni-Holm corrected). In patients with asthma, the predefined primary endpoint (FeNO) showed no significant improvement. In contrast, patient-reported outcomes improved significantly, with clinically relevant gains in asthma control (ACT: p\u2009&lt;\u20090.001) and asthma-related quality of life (total AQLQ: p\u2009=\u20090.005). Lung function parameters showed statistically significant but modest improvements at T2 (FVC: p\u2009=\u20090.011; PEF: p\u2009=\u20090.010; FEV\u2081 in participants\u2009&lt;\u200970 years: p\u2009=\u20090.035). In patients with COPD, symptom burden improved according to CAT scores (p\u2009=\u20090.036), while no improvements in lung function were observed. Patients with Long COVID reported significant improvements in dysfunctional breathing (NQ: T2: p\u2009=\u20090.014), dyspnea (T2: p\u2009=\u20090.026; T3: p\u2009=\u20090.001), and \u201cproblems with stair climbing\/muscle exertion\u201d (T2: p\u2009=\u20090.042), as well as improvements in anxiety and sleep-related symptoms (T2: p\u2009=\u20090.021). No improvements in lung function were observed in this group. In the total cohort, the intervention group showed statistically significant improvements compared to controls in respiratory muscle strength (MIP: p\u2009=\u20090.002; MEP: p\u2009=\u20090.018) and dysfunctional breathing (NQ scores at T2: p\u2009=\u20090.007; T3: p\u2009=\u20090.017). In CO\u2082-rich speleotherapy centers, both SpCO\u2082 (p\u2009=\u20090.026) and PetCO\u2082 (p\u2009&lt;\u20090.001) increased at T2. While speleotherapy did not improve FeNO, it was associated with clinically relevant improvements in patient-reported outcomes across disease groups. Changes in lung function and respiratory muscle strength were statistically significant but modest and should be interpreted with caution. Overall, speleotherapy may have direct effects on the airways and breathing regulation, with more consistent evidence for improvements in breathing patterns than for direct effects on the airways.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>Trial registration<\/jats:bold>\n                    : DRKS00033365 (retrospectively registered).\n                  <\/jats:p>","DOI":"10.1038\/s41598-026-52301-4","type":"journal-article","created":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T03:36:23Z","timestamp":1779420983000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A randomized controlled trial of adjunctive speleotherapy in asthma, COPD and long COVID"],"prefix":"10.1038","volume":"16","clinical-trial-number":[{"clinical-trial-number":"drks00033365","registry":"10.18810\/drks"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7971-7407","authenticated-orcid":false,"given":"Joachim","family":"Schwarz","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5715-3422","authenticated-orcid":false,"given":"Madelaine","family":"Eicke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-9685-7191","authenticated-orcid":false,"given":"Nina","family":"Schwedler","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3831-9996","authenticated-orcid":false,"given":"Gerrit","family":"von Komorowski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-3216-3764","authenticated-orcid":false,"given":"Verena","family":"Goldfuss","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0503-6656","authenticated-orcid":false,"given":"Wolfgang","family":"Fladerer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-5331-1165","authenticated-orcid":false,"given":"B\u00e9atrice","family":"Barbolan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-1890-064X","authenticated-orcid":false,"given":"Martin","family":"Mogk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8915-7762","authenticated-orcid":false,"given":"Natascha","family":"Sommer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"issue":"6","key":"52301_CR1","doi-asserted-by":"publisher","first-page":"585","DOI":"10.1016\/S2213-2600(20)30105-3","volume":"8","author":"GBD Chronic Respiratory Disease Collaborators","year":"2020","unstructured":"GBD Chronic Respiratory Disease Collaborators. Prevalence and attributable health burden of chronic respiratory diseases, 1990\u20132017: A systematic analysis from the Global Burden of Disease Study 2017. Lancet Respir. Med. 8(6), 585\u2013596. https:\/\/doi.org\/10.1016\/S2213-2600(20)30105-3 (2020).","journal-title":"Lancet Respir. Med."},{"key":"52301_CR2","unstructured":"Wissenschaftliches Institut der Ortskrankenkassen (WIdO). Gesundheitsatlas Deutschland \u2013 COPD. Available from: https:\/\/www.gesundheitsatlas-deutschland.de\/erkrankung\/copd. Accessed 14 August 2025"},{"key":"52301_CR3","unstructured":"Wissenschaftliches Institut der Ortskrankenkassen (WIdO). Gesundheitsatlas Deutschland \u2013 Asthma. Available from: https:\/\/www.gesundheitsatlas-deutschland.de\/erkrankung\/asthma. Accessed 14 August 2025"},{"issue":"16","key":"52301_CR4","doi-asserted-by":"publisher","first-page":"1604","DOI":"10.1001\/jama.2022.18931","volume":"328","author":"HE Davis","year":"2022","unstructured":"Davis, H. E., McCorkell, L., Vogel, J. M. & Topol, E. J. Estimated global proportions of individuals with persistent fatigue, cognitive, and respiratory symptom clusters following symptomatic COVID-19 in 2020 and 2021. JAMA 328(16), 1604\u20131615. https:\/\/doi.org\/10.1001\/jama.2022.18931 (2022).","journal-title":"JAMA"},{"key":"52301_CR5","doi-asserted-by":"publisher","DOI":"10.1186\/s12931-023-02475-6","volume":"24","author":"Z Wang","year":"2023","unstructured":"Wang, Z. et al. Global, regional, and national burden of asthma and its attributable risk factors from 1990 to 2019: A systematic analysis for the Global Burden of Disease Study 2019. Respir. Res. 24, 169. https:\/\/doi.org\/10.1186\/s12931-023-02475-6 (2023).","journal-title":"Respir. Res."},{"key":"52301_CR6","unstructured":"Bundes\u00e4rztekammer, Kassen\u00e4rztliche Bundesvereinigung, Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften. Nationale Versorgungsleitlinie Asthma, Version 5.0. 2024. Available from: https:\/\/register.awmf.org\/de\/leitlinien\/detail\/nvl-002. Accessed 14 August 2025"},{"issue":"03","key":"52301_CR7","doi-asserted-by":"publisher","first-page":"175","DOI":"10.1055\/a-2085-7328","volume":"72","author":"J Schwarz","year":"2023","unstructured":"Schwarz, J. Heilstollentherapie \u2013 ein traditionelles Naturheilmittel f\u00fcr Atemwegserkrankungen. Erfahrungsheilkunde 72(03), 175\u2013181. https:\/\/doi.org\/10.1055\/a-2085-7328 (2023).","journal-title":"Erfahrungsheilkunde"},{"key":"52301_CR8","unstructured":"Deutscher Heilb\u00e4derverband, Deutscher Tourismusverband. Begriffsbestimmungen\/Qualit\u00e4tsstandards f\u00fcr Heilb\u00e4der und Kurorte. 13. Auflage. 2018\/2019."},{"key":"52301_CR9","doi-asserted-by":"crossref","unstructured":"Lemko O, Lemko I. Speleotherapy, halotherapy, haloaerosoltherapy: definitions, mechanisms of influence, perspectives of usage (Part I). Asthma and Allergy. 2017;2. ISSN 2307\u20133373","DOI":"10.31655\/2307-3373-2018-3-34-41"},{"issue":"5","key":"52301_CR10","doi-asserted-by":"publisher","first-page":"289","DOI":"10.1016\/s0301-0546(04)79257-5","volume":"32","author":"E Kurta","year":"2004","unstructured":"Kurta, E., Bavbeka, S., Pasaoglu, G., Abadoglu, O. & Misirligil, Z. Use of alternative medicines by allergic patients in Turkey. Allergol. Immunopathol. (Madr.) 32(5), 289\u2013294. https:\/\/doi.org\/10.1016\/s0301-0546(04)79257-5 (2004).","journal-title":"Allergol. Immunopathol. (Madr.)"},{"key":"52301_CR11","doi-asserted-by":"publisher","first-page":"144","DOI":"10.1055\/s-0030-1249701","volume":"20","author":"W Gaus","year":"2010","unstructured":"Gaus, W. & Weber, H. Efficacy and safety of speleotherapy in children with asthma bronchiale: A controlled randomized multicentre study. Phys. Med. Rehabil. Kuror. 20, 144\u2013151. https:\/\/doi.org\/10.1055\/s-0030-1249701 (2010).","journal-title":"Phys. Med. Rehabil. Kuror."},{"issue":"1","key":"52301_CR12","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1016\/j.jaci.2003.09.008","volume":"113","author":"RA Nathan","year":"2004","unstructured":"Nathan, R. A. et al. Development of the Asthma Control Test: a survey for assessing asthma control. J. Allergy Clin. Immunol. 113(1), 59\u201365. https:\/\/doi.org\/10.1016\/j.jaci.2003.09.008 (2004).","journal-title":"J. Allergy Clin. Immunol."},{"issue":"2","key":"52301_CR13","doi-asserted-by":"publisher","first-page":"76","DOI":"10.1136\/thx.47.2.76","volume":"47","author":"EF Juniper","year":"1992","unstructured":"Juniper, E. F. et al. Evaluation of impairment of health related quality of life in asthma: Development of a questionnaire for use in clinical trials. Thorax 47(2), 76\u201383. https:\/\/doi.org\/10.1136\/thx.47.2.76 (1992).","journal-title":"Thorax"},{"issue":"3","key":"52301_CR14","doi-asserted-by":"publisher","first-page":"648","DOI":"10.1183\/09031936.00102509","volume":"34","author":"PW Jones","year":"2009","unstructured":"Jones, P. W. et al. Development and first validation of the COPD Assessment Test. Eur. Respir. J. 34(3), 648\u2013654. https:\/\/doi.org\/10.1183\/09031936.00102509 (2009).","journal-title":"Eur. Respir. J."},{"issue":"6","key":"52301_CR15","doi-asserted-by":"publisher","first-page":"1321","DOI":"10.1164\/ajrccm\/145.6.1321","volume":"145","author":"PW Jones","year":"1992","unstructured":"Jones, P. W., Quirk, F. H., Baveystock, C. M. & Littlejohns, P. A self-complete measure of health status for chronic airflow limitation. The St George\u2019s Respiratory Questionnaire. Am. Rev. Respir. Dis. 145(6), 1321\u20131327. https:\/\/doi.org\/10.1164\/ajrccm\/145.6.1321 (1992).","journal-title":"Am. Rev. Respir. Dis."},{"issue":"2","key":"52301_CR16","doi-asserted-by":"publisher","first-page":"199","DOI":"10.1016\/0022-3999(85)90042-X","volume":"29","author":"J van Dixhoorn","year":"1985","unstructured":"van Dixhoorn, J. & Duivenvoorden, H. J. Efficacy of Nijmegen Questionnaire in recognition of the hyperventilation syndrome. J. Psychosom. Res. 29(2), 199\u2013206 (1985).","journal-title":"J. Psychosom. Res."},{"key":"52301_CR17","doi-asserted-by":"publisher","first-page":"345","DOI":"10.1016\/S0022-3999(02)00392-6","volume":"54","author":"HJ Michielsen","year":"2003","unstructured":"Michielsen, H. J., De Vries, J. & Van Heck, G. L. Psychometric qualities of a brief self-rated fatigue measure: The Fatigue Assessment Scale (FAS). J. Psychosom. Res. 54, 345\u2013352 (2003).","journal-title":"J. Psychosom. Res."},{"key":"52301_CR18","unstructured":"Sch\u00fcller PO. Long-COVID-Fragebogen (Medina-Fragebogen) [unver\u00f6ffentlichtes Erhebungsinstrument]. MEDIAN Klinik Flechtingen; 2023."},{"key":"52301_CR19","volume-title":"Nichtparametrische Analyse longitudinaler Daten","author":"E Brunner","year":"1999","unstructured":"Brunner, E. & Langer, F. Nichtparametrische Analyse longitudinaler Daten (Oldenbourg Verlag, 1999)."},{"issue":"5","key":"52301_CR20","doi-asserted-by":"publisher","first-page":"551","DOI":"10.1164\/rccm.201503-0426OC","volume":"192","author":"RM Dunn","year":"2015","unstructured":"Dunn, R. M. et al. Impact of age and sex on response to asthma therapy. Am J Respir Crit Care Med. 192(5), 551\u2013558. https:\/\/doi.org\/10.1164\/rccm.201503-0426OC (2015).","journal-title":"Am J Respir Crit Care Med."},{"key":"52301_CR21","doi-asserted-by":"publisher","unstructured":"Schatz M, Kosinski M, Yarlas AS, et al. The minimally important difference of the Asthma Control Test. J Allergy Clin Immunol. 2009;124(4):719\u2013723 e1. https:\/\/doi.org\/10.1016\/j.jaci.2009.06.053.","DOI":"10.1016\/j.jaci.2009.06.053"},{"issue":"1","key":"52301_CR22","doi-asserted-by":"publisher","first-page":"81","DOI":"10.1016\/0895-4356(94)90036-1","volume":"47","author":"EF Juniper","year":"1994","unstructured":"Juniper, E. F., Guyatt, G. H., Willan, A. & Griffith, L. E. Determining a minimal important change in a disease-specific quality of life questionnaire. J. Clin. Epidemiol. 47(1), 81\u201387. https:\/\/doi.org\/10.1016\/0895-4356(94)90036-1 (1994).","journal-title":"J. Clin. Epidemiol."},{"key":"52301_CR23","doi-asserted-by":"publisher","DOI":"10.1183\/16000617.0137-2019","volume":"29","author":"M Bonini","year":"2020","unstructured":"Bonini, M. et al. Minimal clinically important difference for asthma endpoints an expert consensus report. Eur. Respir. Rev. 29, 190137. https:\/\/doi.org\/10.1183\/16000617.0137-2019 (2020).","journal-title":"Eur. Respir. Rev."},{"issue":"1","key":"52301_CR24","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/13814788.2019.1574742","volume":"25","author":"M Schuers","year":"2019","unstructured":"Schuers, M., Chapron, A., Guihard, H., Bouchez, T. & Darmon, D. Impact of non-drug therapies on asthma control: A systematic review of the literature. Eur. J. Gen. Pract. 25(1), 1\u201312. https:\/\/doi.org\/10.1080\/13814788.2019.1574742 (2019).","journal-title":"Eur. J. Gen. Pract."},{"issue":"2","key":"52301_CR25","doi-asserted-by":"publisher","first-page":"96","DOI":"10.1159\/000287219","volume":"21","author":"A Schuh","year":"2009","unstructured":"Schuh, A. Die Evidenz der Klima- und Thalassotherapie. Ein Review. Schweiz Z Ganzheitsmed. 21(2), 96\u2013104. https:\/\/doi.org\/10.1159\/000287219 (2009).","journal-title":"Ein Review. Schweiz Z Ganzheitsmed."},{"key":"52301_CR26","doi-asserted-by":"publisher","DOI":"10.3389\/falgy.2024.1483430","volume":"5","author":"W Gu","year":"2024","unstructured":"Gu, W. et al. Association of humidity and precipitation with asthma: A systematic review and meta-analysis. Front. Allergy 5, 1483430. https:\/\/doi.org\/10.3389\/falgy.2024.1483430 (2024).","journal-title":"Front. Allergy"},{"key":"52301_CR27","first-page":"149","volume":"2","author":"K Spannnagel","year":"1961","unstructured":"Spannnagel, K. Die medizinische Wirkung der Kluterth\u00f6hle auf das Asthma bronchiale und die chronische Bronchitis. Jahreshefte Karst H\u00f6hlenkd. 2, 149\u2013159 (1961).","journal-title":"Jahreshefte Karst H\u00f6hlenkd."},{"key":"52301_CR28","unstructured":"Huber C. Klimatische und lufthygienische Qualit\u00e4tsstandards f\u00fcr Spel\u00e4otherapieeinrichtungen. Dissertation. Universit\u00e4t Freiburg; 2004. https:\/\/freidok.uni-freiburg.de\/data\/1583. Accessed 14 August 2025"},{"key":"52301_CR29","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1016\/S1615-9071(21)00111-8","volume":"22","author":"T Liem","year":"2021","unstructured":"Liem, T. Vagusaktivierung und Stressreaktion aus Sicht der Osteopathie. Osteopath. Med. 22, 10\u201315. https:\/\/doi.org\/10.1016\/S1615-9071(21)00111-8 (2021).","journal-title":"Osteopath. Med."},{"issue":"9","key":"52301_CR30","doi-asserted-by":"publisher","first-page":"1388","DOI":"10.1016\/j.rmed.2011.05.004","volume":"105","author":"WP de Kleijn","year":"2011","unstructured":"de Kleijn, W. P., De Vries, J., Wijnen, P. A. H. M. & Drent, M. Minimal (clinically) important differences for the Fatigue Assessment Scale in sarcoidosis. Respir. Med. 105(9), 1388\u20131395. https:\/\/doi.org\/10.1016\/j.rmed.2011.05.004 (2011).","journal-title":"Respir. Med."},{"issue":"3","key":"52301_CR31","doi-asserted-by":"publisher","first-page":"195","DOI":"10.1016\/S2213-2600(14)70001-3","volume":"2","author":"SS Kon","year":"2014","unstructured":"Kon, S. S. et al. Minimum clinically important difference for the COPD Assessment Test: A prospective analysis. Lancet. Respir. Med. 2(3), 195\u2013203. https:\/\/doi.org\/10.1016\/S2213-2600(14)70001-3 (2014).","journal-title":"Lancet. Respir. Med."},{"key":"52301_CR32","doi-asserted-by":"publisher","DOI":"10.1055\/a-2776-9933","author":"J Schwarz","year":"2025","unstructured":"Schwarz, J., Banaei, F., Haus, J., Mogk, M. & Sommer, N. Spel\u00e4otherapie im Rahmen einer multimodalen Rehabilitationsbehandlung bei einer Long-Covid-Erkrankung. Phys. Med. Rehabil. Kuror. https:\/\/doi.org\/10.1055\/a-2776-9933 (2026).","journal-title":"Phys. Med. Rehabil. Kuror."}],"container-title":["Scientific Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.nature.com\/articles\/s41598-026-52301-4","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41598-026-52301-4.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41598-026-52301-4.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T03:51:17Z","timestamp":1779421877000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.nature.com\/articles\/s41598-026-52301-4"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,22]]},"references-count":32,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["52301"],"URL":"https:\/\/doi.org\/10.1038\/s41598-026-52301-4","relation":{},"ISSN":["2045-2322"],"issn-type":[{"value":"2045-2322","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,22]]},"assertion":[{"value":"11 December 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"4 May 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"22 May 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Joachim Schwarz is President of the German Speleotherapy Association; he received an honorarium of \u20ac10,000 from the German Speleotherapy Association for organizing and supervising the present study. Martin Mogk, from the company moreData, was commissioned by the German Speleotherapy Association to conduct the statistical analysis of the study and received an honorarium of \u20ac7,735. The remaining authors declare no conflicts of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}},{"value":"Ethics Committee of the State Medical Association of Rhineland-Palatinate: primary review, March 19, 2024; Application number: 2024-17426 \u2013 other research, primary review. Ethics Committee of the State Medical Association of Baden-W\u00fcrttemberg: secondary review, April 12, 2024; Internal reference number: B-F-2024-038; Study protocol code: 2024-17426. Ethics Committee of the State Medical Association of Bavaria: no obligation for consultation or notification in the presence of a primary review. If an opinion on the research project has already been issued by an ethics committee established under state law, the requirements of \u00a715 of the Professional Code of Conduct for Physicians in Bavaria are deemed to be fulfilled (Ethics Committee of the BL\u00c4K acting in an advisory capacity according to \u00a715 BO). Ethics Committee of the State Medical Association of Lower Saxony: approval granted, April 5, 2024; Reference number: Grae\/030\/2024. Ethics Committee of the State Medical Association of Westphalia-Lippe: approval granted, April 11, 2024; Reference number: 2024-203-b-S. Ethics Committee of the State Medical Association of Thuringia: approval granted, April 12, 2024; Reference number: 80961\/2024\/25. Ethics Committee of Carinthia, Austria: study not subject to mandatory application, February 1, 2024; Email dated February 1, 2024. Ethics Committee for Clinical Research of the Autonomous Province of Bolzano, Italy: approval granted, May 15, 2024; Reference number 33-2024.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval"}}],"article-number":"15986"}}