Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Retrospectively 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

Prof Theresa Marteau


Contact details

Psychology Dept. (at Guy's)
Health Psychology Section
Psychology & Genetics Research Group
5th Floor Thomas Guy House
Guy's Campus
London Bridge
United Kingdom
+44 (0)20 7188 0192

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Didactic versus informed choice invitations to screening: balancing public health benefits and individual choice



Study hypothesis

We propose to develop a feasible and effective informed choice strategy and to evaluate its impact on attendance at screening and motivation to follow subsequent advice, both overall and stratified by social deprivation. The work is set within the important public health context of screening for type two diabetes. We will test two hypotheses:
1. Uptake of screening for diabetes is higher following a traditional, didactic invitation compared with an informed choice invitation.
2. Amongst those who attend for screening, intentions to change behaviour to reduce risks are stronger following an informed choice invitation compared with a traditional invitation.

Ethics approval

Cambridgeshire 1 Research Ethics Committee gave approval on the 5th May 2006 (ref: 06/Q0104/17)

Study design

Multicentre single-blind randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Informed choice for screening for type two diabetes


1. Traditional invitation:
This will be a brief letter based on previous invitations for screening tests, including diabetes and coronary heart disease. It will include:
a. name of the condition i.e. type two diabetes
b. aims of screening i.e. to reduce risks of diabetes and associated cardiovascular disease
c. procedure i.e. review of risk including blood tests and clinical measures, advice and treatment as indicated

2. Informed choice invitation:
This will comprise the same brief letter but with additional detailed information based on General Medical Council (GMC) guidelines, and linked to a self-administered informed choice aid based on similar tools successfully used to facilitate personal decisions in other health care contexts.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Uptake of screening, which will be recorded by the practice nurses conducting the screening.

Secondary outcome measures

1. Intention to change behaviour to reduce risks of diabetes: behavioural intentions are good predictors of behaviour change. Three core behavioural intentions will be assessed in those attending:
a. increasing physical activity
b. restricting calories by eating low fat foods
c. taking preventive medication, if indicated
d. stopping smoking will also be assessed, when relevant
2. Self-reported behaviour assessed using standard questionnaires:
a. physical activity
b. diet
c. smoking and use of medication to reduce risk of diabetes
3. Attendance for post screening blood tests and subsequent practice nurse advice will be recorded
4. Social deprivation: area (post code) and individual level measures (education, home ownership and access to car) will be used. Age, gender, and ethnic group and risk factors known before screening will also be recorded.
5. Risk stratification: all those attending will be given a risk score to indicate their risks of developing diabetes and experiencing a cardiovascular event over the next ten years. Those with confirmed diabetes, expected to be about 30 individuals, will also receive their Coronary Heart Disease (CHD) risk scores
6. Informed choice: choices to participate in screening will be classified as informed to the extent that they are based on understanding diabetes screening and reflect the decision-maker’s values, using a standardised method we have developed and validated in other screening contexts

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. 1200 men and women aged 40 to 69 years
2. In the top 20% of risk of undiagnosed diabetes on practice registers, defined by a validated risk score applied to routine data on general practice population registers. The Cambridge Diabetes Risk Score includes the following risk variables:
a. age
b. gender
c. family history of diabetes
d. smoking status
e. prescription of steroid or anti-hypertensive medication
f. body mass index

Participant type


Age group




Target number of participants

1200 - but the study is sufficiently powered at 585

Participant exclusion criteria

Patients considered by the practice nurse or General Practitioner to be unsuitable for the project, for example, people who are severely ill, will be excluded from the study.

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Psychology Dept. (at Guy's)
United Kingdom

Sponsor information


King's College London (UK)

Sponsor details

Institute of Psychiatry
De Crespigny Park
United Kingdom

Sponsor type




Funder type


Funder name

The Wellcome Trust (UK) (ref: 076838)

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. 2009 protocol in
2. 2010 results in
3. 2011 results in

Publication citations

  1. Protocol

    Mann E, Prevost AT, Griffin S, Kellar I, Sutton S, Parker M, Sanderson S, Kinmonth AL, Marteau TM, Impact of an informed choice invitation on uptake of screening for diabetes in primary care (DICISION): trial protocol., BMC Public Health, 2009, 9, 63, doi: 10.1186/1471-2458-9-63.

  2. Results

    Marteau TM, Mann E, Prevost AT, Vasconcelos JC, Kellar I, Sanderson S, Parker M, Griffin S, Sutton S, Kinmonth AL, Impact of an informed choice invitation on uptake of screening for diabetes in primary care (DICISION): randomised trial., BMJ, 2010, 340, c2138.

  3. Results

    Kellar I, Mann E, Kinmonth AL, Prevost AT, Sutton S, Marteau TM, Can informed choice invitations lead to inequities in intentions to make lifestyle changes among participants in a primary care diabetes screening programme? Evidence from a randomized trial., Public Health, 2011, 125, 9, 645-652, doi: 10.1016/j.puhe.2011.05.010.

Additional files

Editorial Notes