Plain English Summary
Background and study aims
Within the European Union (EU), pharmaceutical licence holders have to make public information on potential adverse effects associated with medicines. EU guidance is that this information should include estimated frequencies of any effects; however, there is uncertainty about the most effective way to do this. In the UK two influential organisations, the MHRA and NICE, have advocated using risk expressions that combine a numerical estimator and a verbal term: e.g. "this side effect is common (it may affect more than 1 in 100 people)". However, there is no apparent evidence to support this recommendation and a concern is that the use of the verbal terms (very common, common, uncommon, rare, very rare) may lead to increased risk estimates. There is also a lack of evidence about the risk qualifier terms. In this case, the recommendation is to use the term 'may', although 'will' would seem more accurate.
Who can participate?
Adults accessing the study via two pages (http://www.cancerresearchuk.org/cancer-help/about-cancer/treatment/cancer-drugs/paclitaxel AND http://www.cancerresearchuk.org/cancer-help/about-cancer/treatment/cancer-drugs/) on the Cancer Help UK website.
What does the study involve?
Participants are randomly allocated to receive information on five side effects of Taxol using either a numerical term only or a combined numerical and verbal term, and using either the word 'will' or the word 'may'. Participants read the information and then estimate the frequency of the 5 side effects and of any side effect occurring. They also give estimates of the severity and 'harmfulness' of the side effects, using 5 Likert scales. Finally participants complete 8 questions intended to measure their numeracy skills.
What are the possible benefits and risks of participating?
Potential benefits of participating are to have a clearer understanding of the risks associated with the medicine, Taxol. There are no risks associated with taking part - just the time given to completing the questionnaire.
Where is the study run from?
The study is the result of a collaboration between researchers at the Universities of York and Leeds, and the website Cancer Help UK (owned by the charity Cancer Research UK). The data are held on a database at the University of Leeds. The PI, Dr Peter Knapp, is based at the University of York, UK.
When is the study starting and how long is it expected to run for?
January 2013 to April 2014
Who is funding the study?
1. University of Leeds (UK)
2. University of York (UK)
Who is the main contact?
Dr Peter Knapp
peter.knapp@york.ac.uk
Trial website
Contact information
Type
Scientific
Primary contact
Dr Peter Knapp
ORCID ID
Contact details
Department of Health Sciences
University of York
York
LS10 9DD
United Kingdom
+44 (0)1904 321675
peter.knapp@york.ac.uk
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
York-Leeds CRUK9
Study information
Scientific title
What is the effect of two framing variables on perceived risks associated with the medicine Taxol?
Acronym
CRUK9
Study hypothesis
That participants' risk perceptions will not be influenced by two potential framing influences: first, providing frequency information using numbers alone or a combination of number and words; second, using different verbal qualifiers to convey risk.
Ethics approval
University of Leeds, Institute of Psychological Sciences research Ethics Committee, 22/06/2012, ref: 12-0127
Study design
Factorial trial (2x2) with concealed random allocation of individual participants
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Other
Trial type
Other
Patient information sheet
There is no PIS - that was approved by the REC. There is brief information on the website before people agree to take part. By agreeing to take part, people are confirming that they have received sufficient information about the study.
Condition
Cancer
Intervention
Information. (Risk frequency information presented in one of four ways).
There are four arms to the trial. Participants read the information about the medicines and then answer some questions about it. That is, 'follow-up' is immediate.
In all four arms of the trial participants receive information about 10 potential side effects of Taxol - the way that that risk is expressed varies across the four trial conditions.
The side effects:
1. May affect more than 1 in 10 people.
2. Very common: may affect more than 1 in 10 people
3. Will affect more than 1 in 10 people.
4. Very common: will affect more than 1 in 10 people.
(The incident rate bands vary according to the SE being portrayed).
The trial is evaluating the effect of adding verbal risk terms to the numerical information. Also, the use of the terms 'may' and 'will' to convey risk.
Intervention type
Other
Phase
Drug names
Primary outcome measure
1. Estimated frequency of any side effect occurring
2. Estimates frequency of 5 individual side effects
Secondary outcome measures
1. Estimated severity and degree of harm from the side effects
2. Participants' numeracy
Overall trial start date
01/01/2013
Overall trial end date
01/04/2014
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
Adults (aged 16 or over) accessing the study via two pages (http://www.cancerresearchuk.org/cancer-help/about-cancer/treatment/cancer-drugs/paclitaxel AND http://www.cancerresearchuk.org/cancer-help/about-cancer/treatment/cancer-drugs/) on the Cancer Help UK website.
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
318
Participant exclusion criteria
Does not meet inclusion criteria
Recruitment start date
01/01/2013
Recruitment end date
01/04/2014
Locations
Countries of recruitment
United Kingdom
Trial participating centre
University of York
York
LS10 9DD
United Kingdom
Funders
Funder type
University/education
Funder name
University of Leeds (UK)
Alternative name(s)
Funding Body Type
private sector organisation
Funding Body Subtype
academic
Location
United Kingdom
Funder name
University of York
Alternative name(s)
Funding Body Type
private sector organisation
Funding Body Subtype
academic
Location
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
2016 results in: https://www.ncbi.nlm.nih.gov/pubmed/25645270