Methods for evaluating the extent to which different ways of presenting evidence of the effects of health care help people make decisions that are consistent with their own values: a randomised trial

ISRCTN	ISRCTN14949974
DOI	https://doi.org/10.1186/ISRCTN14949974
Protocol serial number	HIPPO 1
Sponsor	Norwegian Research Council (Norway)
Funder	Norwegian Research Council (Norway) (project 135210 - A series of randomised trials comparing different ways of presenting health evidence on the Internet)

Submission date: 04/01/2007
Registration date: 28/02/2007
Last edited: 03/10/2007

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Other

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr Andrew Oxman
Scientific

Norwegian Knowledge Centre for the Health Services
P.O. Box 7004
St Olavs Plass
Oslo
0130
Norway

Study information

Primary study design	Interventional
Study design	Randomised controlled trial
Secondary study design	Randomised controlled trial
Scientific title
Study acronym	HIPPO pilot
Study objectives	Pilot study - development of methodology to: 1. Analyse which of several presentations of evidence of treatment effects best help people to make treatment decisions congruent with their own values 2. Compare visual analogue scales and category rating scales as value elicitation instruments
Ethics approval(s)	This study was approved by the ethics review board at the University at Buffalo on the 15 May 2002 with several renewals.
Health condition(s) or problem(s) studied	N/A
Intervention	Six different summary statistics presenting ten year risk reduction effect of statins on coronary heart disease in the treatment of hypercholesteremia. The methodological aspects reported in this study include comparison of two value elicitation instruments (visual analogue scales and category rating scales), four theory-grounded approaches to weighting elicited values, and six summary statistics to evaluate the extent to which they promote decisions consistent with elicited values. In addition, we report hypothesis generation and sample size calculation for a randomised controlled trial comparing the same six summary statistics for communicating evidence of reduced risk of coronary heart disease, as well as on the feasibility of conducting this type of Internet-based randomised trial.
Intervention type	Other
Primary outcome measure(s)	1. Acceptance or rejection of statin treatment 2. Estimated probability to accept or reject statin treatment in relation to value score
Key secondary outcome measure(s)	1. To investigate the feasibility of conducting Internet-based randomised trials comparing different risk reduction presentations 2. To compare two methods of eliciting values 3. Four ways of weighting the elicited values to calculate a total value 4. To generate hypotheses and calculate sample size for a confirmatory study comparing six summary statistics for communicating evidence of reduced risk of Coronary Heart Disease (CHD) with statin therapy for treatment of high cholesterol
Completion date	04/12/2002

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	All
Target sample size at registration	770
Key inclusion criteria	1. 18 years old 2. Fluent in English or Norwegian 3. Must give informed consent
Key exclusion criteria	Not meeting inclusion requirements
Date of first enrolment	31/10/2002
Date of final enrolment	04/12/2002

Locations

Countries of recruitment

Norway
United States of America

Study participating centre

Norwegian Knowledge Centre for the Health Services

Oslo
0130
Norway

Results and Publications

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan