The PITSTOP study

PIlonidal sinus Treatment: STudying the OPtions (PITSTOP): an observational cohort with nested mixed methods and qualitative design to investigate surgical options for the treatment of pilonidal sinus disease.



Pilonidal disease (PD) is common. It affects about 1 in 3800, predominantly young, working people. It involves a painful abscess in the cleft between the buttocks. Many people need emergency surgery. PD recurs for one in five patients, and need further operations. Ideal management of PD should be simple, safe, cost-effective, easy to perform and lead to a rapid return to normal activities, with low rates of acute wound complications, recurrence, and rapid wound healing.

Before PITSTOP, these aims were not met by the most current surgical practice and there was no consensus on how to manage the disease based on different characteristics.


PITSTOP looked at how surgeons treat people with PSD, including what operations were performed and their outcomes. We interviewed patients about their experiences of treatments. Some patients completed a survey to help us understand what procedures they might prefer in future, based on risks and outcomes.

Surgeons completed a survey to tell us about their experiences of treating pilonidal disease, and we explored whether a new tool could help us tell the difference between ‘mild’ and ‘bad’ PSD. We used findings from these studies to help patients and surgeons agree on priorities for future practice and research.


667 patients joined PITSTOP. People who had a major operation had more pain and a delay in return to normal activities, some of which continued six months after surgery. However, disease recurrence was lower after a major operation. Patients based decisions about treatment on the likelihood of success and time to recover.

The study and the surgeon’s survey showed a lot of variation in practice, and surgeons tended to offer one or two operations learned during training. A classification tool put cases in similar groups, but this did not influence treatment choices. The consensus exercise identified five research and five practice priorities.


No impact yet.


Beal EM, Lee MJ, Hind D, Wysocki AP, Yang F & Brown SR (2019) A systematic review of classification systems for pilonidal sinus. Techniques in Coloproctology, 23(5), 435-443.

Strong, E., Callaghan, T., Beal, E., Moffatt, C., Wickramasekera, N., Brown, S., Lee, M. J., Winton, C., Hind, D., Ali, K., Anderson, J., Bradburn, M., Brady, R., Branagan, G., Chater, T., Chaudri, S., Di Fabio, D., Din, F., Donnelly, D., … Wysocki, P. (2021). Patient decision‐making and regret in pilonidal sinus surgery: a mixed‐methods study. Colorectal Disease, 23(6), 1487–1498.

Wickramasekera, N., Strong, E., Shackley, P., Callaghan, T., Lee, M., Hind, D., & Brown, S. (2023). Patient preferences for pilonidal sinus treatments: A discrete choice experiment survey. Colorectal Disease, 25(5), 984–994.



PITSTOP protocol (PDF, 571KB)

PITSTOP survey (DOC, 30KB)


Central study staff





Professor Steven Brown  Chief Investigator Sheffield Teaching Hospitals NHS Foundation Trust
Emily Strong Research Assistant University of Sheffield
Daniel Hind CTRU Oversight University of Sheffield
Heather Dakin Trial Support Officer University of Sheffield





Catherine Winton Patient Representative  University of Sheffield 
Ryan Edridge Patient Representative University of Sheffield 
Jon Lund Consultant Surgeon  Derby Royal Infirmary
Daniel Hind Assistant Director  University of Sheffield 
Asha Senapati Consultant Surgeon  Portsmouth Hospital 
Jonathon Morton Consultant Surgeon  Addenbrookes Hospital 
Christine Moffatt Professor of Clinical Nursing Research University of Nottingham 
Farhat Din Consultant Surgeon  University of Edinburgh 
Matthew Lee Clinical Research Fellow (Registrar)  Sheffield Teaching Hospitals NHS Foundation Trust
Peter Vaughan-Shaw Clinical Research Fellow (Registrar) University of Edinburgh 
Philip Shackley Reader in Health Economics  University of Sheffield 
Mike Bradburn  Medical Statistician  University of Sheffield 
Ellen Lee Medical Statistician  University of Sheffield 


This study is funded by NIHR Health Technology Assessment (HTA 17/17/02). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.


Sheffield Teaching Hospitals

Centres of excellence

The University's cross-faculty research centres harness our interdisciplinary expertise to solve the world's most pressing challenges.