Water assisted flexible sigmoidoscopy in NHS Bowel Scope Screening Programme

ISRCTN	ISRCTN81466870
DOI	https://doi.org/10.1186/ISRCTN81466870
Protocol serial number	35866
Sponsor	North Tees & Hartlepool NHS Foundation Trust
Funder	NIHR Central Commissioning Facility (CCF); Grant Codes: PB-PG-1215-20035

Submission date: 04/04/2018
Registration date: 12/04/2018
Last edited: 29/06/2021

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Digestive System

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Background and study aims
Bowel cancer is the second most common cause of cancer death in the UK. Around 1 in 14 men and 1 in 19 women will develop bowel cancer. To reduce this risk, the NHS Bowel Screening Programme has started inviting all 55 year olds for a sigmoidoscopy. This involves examining the lower bowel with a thin flexible tube with a camera on it, via the back passage. Research has shown that this test reduces bowel cancer death by 41%. During the test, the bowel is inflated with carbon dioxide, to allow passage of the camera. The problem is that bowel distention can cause pain. National surveys show that over 1 in 3 patients report moderate or severe pain. The aim of this study is to assess whether using water to minimise bowel distension, instead of gas, will make the procedure more comfortable. Early studies suggest this may be effective, but this needs to be confirmed in UK practice. It is hoped that by reducing pain, people will have a better experience, which may increase public uptake of screening. Currently only 43.7% of people participate –more cancers can be prevented if participation increases.

Who can participate?
Healthy volunteers referred for screening flexible sigmoidoscopy via the NHS Bowel Scope Screening Programme

What does the study involve?
Participants are randomly allocated to either have the current standard sigmoidoscopy using carbon dioxide, or to have sigmoidoscopy using water. Participants are then asked how comfortable they found the test. The study also measures which technique finds more polyps (small growths that may have cancerous potential).

What are the possible benefits and risks of participating?
The endoscopists performing the procedure may be able to deliver a more comfortable procedure for patients and may also be able to find more polyps. The study may not benefit the participants now, but the results may help others who have sigmoidoscopy in the future. There have been no safety issues reported with water-assisted sigmoidoscopy in any study so far. Discomfort is a possibility in either type of sigmoidoscopy procedure (normal CO2 sigmoidoscopy and water-assisted sigmoidoscopy). As part of the study side effects (such as discomfort and incontinence during or after the procedure) as well as overall experience during the flexible sigmoidoscopy are measured.

Where is the study run from?
1. North Tees and Hartlepool NHS Foundation Trust (UK)
2. St Mark's Hospital, London (UK)
3. South Tyneside NHS Foundation Trust (UK)
4. Queen Elizabeth Hospital Gateshead (UK)
5. County Durham and Darlington NHS Foundation Trust (UK)

When is the study starting and how long is it expected to run for?
June 2017 to November 2019

Who is funding the study?
National Institute for Health Research (NIHR) (UK)

Who is the main contact?
Mrs Jill Deane
jill.deane@nth.nhs.uk

Contact information

Mrs Jill Deane
Scientific

Research Office
2nd Floor, South Wing
University Hospital of North Tees
Hardwick
Stockton on Tees
TS19 8PE
United Kingdom

Phone	+44 (0)1642 624582
Email	jill.deane@nth.nhs.uk

Study information

Primary study design	Interventional
Study design	Randomised; Interventional; Design type: Treatment, Other
Secondary study design	Randomised controlled trial
Study type	Participant information sheet
Scientific title	The WASH study: water assisted sigmoidoscopy in NHS Bowel Scope Screening Programme: a randomised multicentre study
Study acronym	WASH
Study objectives	1. Water-assisted sigmoidoscopy (WAS) will lead to decreased procedural pain, when compared with standard CO2-assisted (CO2) insertion, resulting in better patient experience during screening 2. WAS improves other key screening performance indicators such as the adenoma (cancer precursor) detection rate
Ethics approval(s)	NRES Committee North East, 10/11/2017, ref: 17/NE/0309
Health condition(s) or problem(s) studied	Other examination or investigation
Intervention	Patients will be randomised using a secure, web-based platform that can be accessed 24 hours a day, which was developed and is maintained by NWORTH. The randomisation uses dynamic allocation to ensure a consistent balance to the allocation ratio of 1:1 and within any stratification variable. Treatment: water-assisted flexible sigmoidoscopy (FSIG) utilising the WAS technique Control: standard CO2 assisted flexible sigmoidoscopy The trialists will then ask patients how comfortable they found the test and measure which technique finds more adenomas. Follow-up is for 14 days following procedure (sigmoidoscopy).
Intervention type	Procedure/Surgery
Primary outcome measure(s)	Pain is measured using a standard Likert scale (4-point) (“None/ Mild / Moderate / Severe”) post-procedure/pre-discharge and 24 hours afterwards via patient questionnaire
Key secondary outcome measure(s)	The key secondary outcome will be the adenoma detection rate (ADR), the key performance indicator for the accuracy of sigmoidoscopy in detecting pre-malignant polyps (adenomas). This is measured at 14 days following review of all histology reports of patient who have polyps removed Other secondary measures include: 1. Procedural pain as rated by patients on a Visual Analogue Scale (VAS) immediately after procedure [post-procedure, pre-discharge] 2. Other aspects of patients’ experience, by a post-discharge questionnaire assessing embarrassment, willingness to repeat the procedure, expected versus experienced pain, overall satisfaction and symptoms post-procedure. 3. The sigmoidoscopy insertion times (SITs) 4. The sigmoidoscopy withdrawal times (SWTs) in negative procedures (i.e. without polyps) 5. The maximum extent of insertion (segment, i.e. rectum, distal sigmoid, proximal sigmoid, distal descending, proximal descending, splenic flexure, distal transverse; as judged by the endoscopist) – this will be the primary means to estimate extent of insertion 6. The final length of scope inserted just prior to withdrawal (scope length in cm) – this will be used as a surrogate for how straight/looped the scope is (stratifying by segment extent) 7. The mean number of adenomas per procedure (MAP) 8. The percentage of procedures where Entonox was used on demand (i.e. as an adjunct in case of procedural pain per patient’s wish). This will not be applicable in procedures where participants prefer to start their procedure with Entonox use 9. The quality of mucosal views on withdrawal using the validated Boston Bowel Preparation Scale 10. The percentage of procedures where a second enema was needed (due to poor mucosal views) 11. The percentage of procedures where hand pressure was required (ancillary manoeuvre to aid insertion) 12. The percentage of procedures where patient position shifts were required (ancillary manoeuvre to aid insertion) 13. The conversion rate from WAS to CO2, or CO2 to WAS technique 14. The volume of water and CO2 used in WAS and CO2 arms 15. The number and type of endoscope loops identified with magnetic scope guide (where scope guide used) 16. The endoscopist learning curve of WAS technique during the training period (prior to commencing the trial) by capturing endoscopists’ reported confidence in performing the procedure, their attitude towards the technique (negative, neutral, positive) before and after completion of training period, as well as procedure times and extent of insertion as the study progresses These outcomes will be analysed on an intention to treat basis. Following this; as per protocol analysis will be considered as appropriate to assess the sensitivity of these results. Exploratory subgroups analyses will be considered for relevant cohorts with previous hysterectomy, irritable bowel syndrome and diverticulosis, as well as for depth of scope insertion (segment and length of scope), scope diameter (adult vs. paediatric) and model (e.g. Olympus 240/260/290) and individual endoscopists all considered.
Completion date	30/11/2019

Eligibility

Participant type(s)	Healthy volunteer
Age group	Adult
Sex	All
Target sample size at registration	1100
Total final enrolment	1125
Key inclusion criteria	1. Referral for screening flexible sigmoidoscopy via the NHS Bowel Scope Screening Programme 2. Ability to give informed consent
Key exclusion criteria	1. Absolute contraindications to sigmoidoscopy 2. Patients lacking capacity to give informed consent 3. Previous left colonic/rectal resection 4. Ongoing antithrombotic treatment (apart from aspirin, which is permitted)
Date of first enrolment	01/12/2017
Date of final enrolment	06/06/2019

Locations

Countries of recruitment

United Kingdom
England
Yemen

Study participating centres

North Tees and Hartlepool NHS Foundation Trust

TS19 8PE
United Kingdom

St Mark's Hospital

London
HA1 3UJ
United Kingdom

South Tyneside NHS Foundation Trust

NE34 0PL
United Kingdom

Queen Elizabeth Hospital

Gateshead
NE9 6SX
United Kingdom

County Durham and Darlington NHS Foundation Trust

DL3 6HX
Yemen

Results and Publications

Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Available on request
IPD sharing plan	Once the trial is complete and all data collection, data cleaning, data analysis and reports are complete the Chief Investigator will be issued with a trial data pack by NOWRTH (all data will be anonymised). Chief Investigator is Professor Matt Rutter (Matt.Rutter@nth.nhs.uk).

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article		07/09/2020	29/06/2021	Yes	No
Protocol article	protocol	01/11/2019	15/11/2019	Yes	No
HRA research summary			28/06/2023	No	No
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes

Editorial Notes

29/06/2021: Publication reference added.
15/11/2019: Publication reference added.
09/07/2019: Internal review.
12/06/2019: The total final enrolment was added.
11/06/2019: The recruitment end date was changed from 31/05/2019 to 06/06/2019.
27/03/2019: The condition has been changed from "Specialty: Gastroenterology, Primary sub-specialty: Endoscopy and imaging; UKCRC code/ Disease: Oral and Gastrointestinal/ Other diseases of the digestive system" to "Other examination or investigation" following a request from the NIHR.