Condition category
Urological and Genital Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Prof David Neal


Contact details

University of Newcastle
Department of Surgery
Framlington Place
Newcastle upon Tyne
United Kingdom
+44 (0)191 222 7067

Additional identifiers

EudraCT number number

Protocol/serial number

941003 r245/02340

Study information

Scientific title


The CLasP Study

Study hypothesis

Ten to fifteen percent of men aged 40 undergo transurethral prostatectomy (TURP) in their lifetime.
About 20% do not achieve satisfactory symptomatic results, 5% to 10% suffer major morbidity and 0.2% to 1% die from the procedure. The annual cost of TURP in the USA is in excess of $3,000,000,000. New, less invasive treatments are now available including laser treatment which may be provided as a day-case procedure. It is unclear how laser treatment compares with TURP or indeed with conservative treatment (watchful waiting - reassurance and advice) in terms of cost, effectiveness, improvement in quality of life and urodynamic outcome. These deficiencies in knowledge are clearly very important to the NHS which cannot afford to take up high cost, high technology treatments unless they are shown to be of clear benefit. We propose carrying out a randomised controlled trial comparing TURP, laser treatment and watchful waiting in men who would normally undergo TURP.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet


Bladder outflow obstruction in men


1. Laser therapy with a noncontact, side firing neodymium:YAG probe
2. TURP (standard transurethral prostatic resection)
3. Watchful waiting (conservative management, including monitoring without active intervention)

Intervention type



Not Specified

Drug names

Primary outcome measure

1. International Prostate Symptom Score (I-PSS)
2. Maximum urinary flow rate
3. A composite measure of success based on I-PSS and maximum urinary flow rate categories
4. I-PSS quality of life score
5. Post-void residual urine volume

Secondary outcome measures

1. Treatment failure
2. Hospital stay
3. Major complications.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Men with uncomplicated lower urinary tract symptom that is not acute or chronic urinary retention.

Participant type


Age group




Target number of participants

106 (added 15/01/10; see publication [2])

Participant exclusion criteria

Does not match inclusion criteria

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

University of Newcastle
Newcastle upon Tyne
United Kingdom

Sponsor information


NHS R&D Regional Programme Register - Department of Health (UK)

Sponsor details

The Department of Health
Richmond House
79 Whitehall
United Kingdom
+44 (0)20 7307 2622

Sponsor type




Funder type


Funder name

NHS Executive Northern and Yorkshire (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

1. 2000 results for men with chronic urinary retention in
2. 2000 results for men with symptoms associated with benign prostatic enlargement in
3. 2001 results in
4. 2002 economic evaluation in
5. 2003 results in

Publication citations

  1. Results for men with chronic urinary retention

    Gujral S, Abrams P, Donovan JL, Neal DE, Brookes ST, Chacko KN, Wright MJ, Timoney AG, Peters TJ, A prospective randomized trial comparing transurethral resection of the prostate and laser therapy in men with chronic urinary retention: The CLasP study., J. Urol., 2000, 164, 1, 59-64.

  2. Results for men with symptoms associated with benign prostatic enlargement

    Donovan JL, Peters TJ, Neal DE, Brookes ST, Gujral S, Chacko KN, Wright M, Kennedy LG, Abrams P, A randomized trial comparing transurethral resection of the prostate, laser therapy and conservative treatment of men with symptoms associated with benign prostatic enlargement: The CLasP study., J. Urol., 2000, 164, 1, 65-70.

  3. Results

    Chacko KN, Donovan JL, Abrams P, Peters TJ, Brookes ST, Thorpe AC, Gujral S, Wright M, Kennedy LG, Neal DE, Transurethral prostatic resection or laser therapy for men with acute urinary retention: the ClasP randomized trial., J. Urol., 2001, 166, 1, 166-70; discussion 170-1.

  4. Economic evaluation

    Noble SM, Coast J, Brookes S, Neal DE, Abrams P, Peters TJ, Donovan JL, Transurethral prostate resection, noncontact laser therapy or conservative management in men with symptoms of benign prostatic enlargement? An economic evaluation., J. Urol., 2002, 168, 6, 2476-2482, doi: 10.1097/

  5. Results

    Brookes S, Peters T, Campbell R, Featherstone K, Neal D, Abrams P, Donovan J, Including a 'no active intervention' arm in surgical trials is possible: evidence from the CLasP randomised trial., J Health Serv Res Policy, 2003, 8, 4, 209-214, doi: 10.1258/135581903322403272.

Additional files

Editorial Notes