What is the effect of alternative summary statistics for communicating risk reduction on decisions about whether to take statins?

ISRCTN ISRCTN85194921
DOI https://doi.org/10.1186/ISRCTN85194921
Secondary identifying numbers N/A
Submission date
09/03/2007
Registration date
04/05/2007
Last edited
02/09/2009
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Circulatory System
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Ms Cheryl Carling
Scientific

PO box 7004
St Olavs Plass
Oslo
N-0130
Norway

Phone +47 (0)98627327
Email cheryl.carling@kunnskapssenteret.no

Study information

Study designRandomised controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Not specified
Study typeOther
Scientific title
Study acronymHIPPO 2 (Health Information Project, Presentation Online)
Study objectivesIn terms of congruence between decisions and values:
1. "Relative risk reduction" is inferior to the “absolute” summary statistics
2. "Absolute risk reduction" is superior to other “absolute” summary statistics, and
3. There is no congruence between decisions and values for "event rates"
Ethics approval(s)Ethics approval received from the University at Buffalo (New York, USA), Health Sciences Institutional Review Board, approved on 15 May 2002.
Health condition(s) or problem(s) studiedHypercholesterolaemia (hypothetical scenario)
InterventionPresentations of summary statistic showing evidence of statins' effectiveness in preventing coronary heart disease over ten years.

The participants viewed one of the following six presentations:
1. Relative risk reduction (RRR)
2. Absolute risk reduction (ARR)
3. Numbers needed to treat (NNT)
4. Event rates (ER)
5. Tablets needed to take (TNT)
6. Whole numbers (WN)
Intervention typeOther
Primary outcome measureHypothetical treatment decision to take or not to take statins.
Secondary outcome measuresUnderstanding of and satisfaction with information, and preferred summary statistic.
Overall study start date01/06/2003
Completion date31/07/2005

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participants4,800
Key inclusion criteria1. At least 18 years of age
2. Fluent in English or Norwegian
Key exclusion criteriaPrevious participation in this trial
Date of first enrolment01/06/2003
Date of final enrolment31/07/2005

Locations

Countries of recruitment

  • Canada
  • Norway
  • United States of America

Study participating centre

PO box 7004
Oslo
N-0130
Norway

Sponsor information

Norwegian Knowledge Centre for the Health Services (Norway)
Other

PO box 7004
St Olavs Plass
Oslo
N-0130
Norway

Phone +47 (0)23 25 50 00
Email post@kunnskapssenteret.no
Website http://www.kunnskapssenteret.no/
ROR logo "ROR" https://ror.org/01thff661

Funders

Funder type

Research council

Norwegian Research Council (Norway)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 01/11/2008 Yes No
Results article results 01/08/2009 Yes No