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The STOP-AB trial protocol: efficacy and safety of discontinuing patient antibiotic treatment when physicians no longer consider it necessary
  1. Carl Llor1,
  2. Ana Moragas2,
  3. Carolina Bayona3,
  4. Josep M Cots4,
  5. José M Molero5,
  6. Joana Ribas6,
  7. Julio Francisco Fóthy7,
  8. Isabel Gutiérrez8,
  9. Coro Sánchez9,
  10. Jesús Ortega10,
  11. Javier Arranz11,
  12. Jenifer Botanes12,
  13. Purificación Robles13
  1. 1 Primary Healthcare Centre Barcelona-2B (Via Roma), Barcelona, Spain
  2. 2 Universitat Rovira i Virgili, Primary Healthcare Centre Jaume I, Tarragona, Spain
  3. 3 Primary Healthcare Centre La Marina, Barcelona, Spain
  4. 4 Universitat of Barcelona, Primary Healthcare Centre La Marina, Barcelona, Spain
  5. 5 Primary Healthcare Centre San Andrés, Madrid, Spain
  6. 6 Primary Healthcare Centre Hospital Son Llàtzer, Palma, Spain
  7. 7 Primary Healthcare Centre Coll d'en Rabassa, Palma, Spain
  8. 8 Primary Healthcare Centre Rondilla I, Valladolid, Spain
  9. 9 Primary Care Centre Virxe da Peregrina, Pontevedra, Spain
  10. 10 Primary Healthcare Centre Rincón de Soto, Rincón de Soto, Spain
  11. 11 Primary Healthcare Centre Arquitecte Bennàssar, Palma, Spain
  12. 12 Primary Healthcare Centre Cornellà de Llobregat, Barcelona, Spain
  13. 13 Primary Care Centre Can Vidalet, Esplugues de Llobregat, Spain
  1. Correspondence to Dr Carl Llor; carles.llor{at}


Introduction Since 2011, the Spanish Society of Family Medicine has recommended general practitioners (GPs) to ask their patients to stop taking antibiotics when they suspect a viral infection. However, this practice is seldom used because uncertainty about diagnosis, and fear of consequences of discontinuing antibiotic therapy, as well as perceived pressure to continue prescribing antibiotics and potential conflict with patients are more of a concern for GPs than antibiotic resistance. The main objective of this study is to determine whether discontinuation of antibiotic therapy when a GP no longer considers it necessary has any impact on the number of days with severe symptoms.

Methods and analysis This is a multicentre, open-label, randomised controlled clinical trial. The study was conducted in 10 primary care centres in Spain. We included patients from 18 to 75 years of age with uncomplicated acute respiratory tract infections—acute rhinosinusitis, acute sore throat, influenza or acute bronchitis—who had previously taken any dose of antibiotic for <3 days, which physicians no longer considered necessary. The patients were randomly assigned to the usual strategy of continuing antibiotic treatment or to discontinuing antibiotic therapy. A sample size of 240 patients per group was calculated on the basis of a reduction of 1 day in the duration of severe symptoms being a clinically relevant outcome. The primary outcome was the duration of severe symptoms, that is, symptoms scored 5 or 6 by means of validated symptom diaries. Secondary outcomes included antibiotics taken, adverse events, patient satisfaction and complications within the first 3 months.

Ethics and dissemination The study was approved by the Ethical Board of Fundació Jordi Gol i Gurina (reference number: 16/093). The findings of this trial will bedisseminated through research conferences and peer-reviewed journals.

Trial registration number NCT02900820; pre-results.

  • Clinical trials
  • Respiratory infections
  • Public health

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

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  • Contributors CL, AM, JMC and CB were involved in the conception and design of the study. JFF, JMM, JR, IG, JA, JO, CS, JB and PR have made substantial contributions to conception and design. AM, JFF, JMM, JR, IG, JA, JO, CS, JB and PR were involved in trial conduct and recruitment. CL drafted the manuscript and all authors read and approved the final manuscript.

  • Funding This work is supported by the Catalan Society of Family Medicine, grant number FAP1601. Neither the funding society nor the sponsor – Spanish Society of Family and Community Medicine – had any role in the design of the study.

  • Competing interests CL reports receiving research grants from the European Commission (Sixth and Seventh Programme Frameworks), Catalan Society of Family Medicine and Instituto de Salud Carlos III (Spanish Ministry of Health).

  • Ethics approval The study was approved by the Primary Care Research and Ethics Committee of the Jordi Gol i Gurina Foundation, Barcelona, Spain (reference number, 16/093).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement All data created during this research will be openly available from the Spanish Society of Family Medicine.

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