Condition category
Nervous System Diseases
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Professor AC Williams


Contact details

Department of Clinical Neurology
University of Birmingham
Queen Elizabeth Hospital
B15 2TH
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title



Study hypothesis

PD SURG will evaluate whether STN surgery has a cost-effective role in the treatment of PD and will also investigate the optimal timing of such surgery. The trial will compare surgery with active medical therapy (with surgery delayed for as long as possible) with respect to patient and carer Quality of Life (QoL), control of the symptoms of PD (short and long term), safety and costs.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type

Not Specified

Patient information sheet

Available in


Neurosciences, psychiatry


Patients in both arms will receive active intervention:
1. In the surgery arm, Subthalamic nucleus stimulation (STN) surgery by stimulation (or possibly lesioning after the start up phase)
2. In the medical therapy arm, drugs will be prescribed as considered appropriate (this will often include continuous apomorphine)

Intervention type



Not Specified

Drug names

Primary outcome measure

Patient's self-evaluation of functional status (using the PDQ-39 questionnaire). It is important that the trial assesses the patients' own perceptions of their functioning and addresses matters of most concern to them. The PDQ-39 is a self-completed questionnaire, specifically developed and tested for use in clinical trials by two of the applicants/collaborators. It reflects patients' concerns in eight aspects of PD: mobility, activities of daily living, emotional well-being, stigma, social support, cognition and bodily discomfort. It has been extensively tested for validity, reproducibility and sensitivity. Affective and cognitive changes are detected by PDQ-39

Secondary outcome measures

1. Quality of life. In addition to PDQ-39, the EuroQoL EQ-5D will be used as the main outcome measure for the Health Economic evaluation (see below) as this permits incremental quality adjusted life-years (QALYs) to be calculated.
2. Dementia screen. The trial aims to determine whether therapies prevent or decrease the decline of cognitive function as measured by the DRS-II. The DRS has the ability to assess the level of cognitive impairment in different clinical populations and to differentiate between types of dementia.
3. Clinical assessment of functioning. The Unified Parkinson's Disease Rating Scale (UPDRS - both on and off drug therapy) and Hoehn & Yahr staging system will provide a standard neurological assessment against which to validate further the PDQ-39 in a subset of patients.
4. Neuropsychology. A semi-structured neuropsychiatric interview and psychometric measures of depression/anxiety, and cognition (pre-morbid/current IQ, language, attention-executive functions, memory and spatial skills) in a subset of patients.
5. Burden on carers. Little is known about the effects of PD and its treatment on carers. The person identified by the patient as their primary carer, if they have one, will be asked to complete the SF36, a well validated measure of health status.
6. Institutionalisation rates and other measures of individual and societal cost.
7. Toxicity and side-effects of surgery, including mortality, stroke and other serious adverse events. Toxicity and side-effects of medical therapy will also be recorded.
8. Death from all causes and specifically from PD and the surgical procedure. Patients will be flagged with the Office for National Statistics (ONS) for long-term mortality follow-up.
Some centres will wish to undertake additional investigations (e.g. more detailed clinical assessments, including video records, neuropsychology, physiology and imaging) and we will encourage such scientific add-on studies, although they will not be part of the main trial.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. They have PD that is not controlled by current medical therapy
2. They are considered fit enough for surgical intervention
3. They are unlikely to be considered to definitely require, and be able to receive, surgery within 1 year of entry
4. They are not demented
5. They are able to understand and complete the trial questionnaires (non-English speaking patients may be entered if they have a carer, relative or other person who can help them)
6. They have given written informed consent

Definite indications for, or contraindications against, any of the therapies in the trial are not specified by the protocol, but by the responsible clinician. Eligibility will be based on the 'uncertainty principle'.

Participant type


Age group

Not Specified


Not Specified

Target number of participants

400-600. Closed to recruitment - in follow-up

Participant exclusion criteria

Not provided at time of registration

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Department of Clinical Neurology
B15 2TH
United Kingdom

Sponsor information


University of Birmingham (UK)

Sponsor details

B15 2TT
United Kingdom

Sponsor type




Funder type

Research council

Funder name

Medical Research Council (MRC) (UK)

Alternative name(s)


Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

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

2010 results in

Publication citations

  1. Results

    Williams A, Gill S, Varma T, Jenkinson C, Quinn N, Mitchell R, Scott R, Ives N, Rick C, Daniels J, Patel S, Wheatley K, , Deep brain stimulation plus best medical therapy versus best medical therapy alone for advanced Parkinson's disease (PD SURG trial): a randomised, open-label trial., Lancet Neurol, 2010, 9, 6, 581-591, doi: 10.1016/S1474-4422(10)70093-4.

Additional files

Editorial Notes