Page 67 - Let them speak Towards a patient reported outcome measure set for

Protocol for developing a core PRO set
Participant groups will align with those in the focus groups and interviews.
Healthcare professionals and European patient representatives will be
merged into one stakeholder group: experts. Participants of the Dutch
and European focus groups and interviews will be contacted again if they
have given their consent. Additional individuals with GID, caregivers, and
experts will be contacted through Dutch patient organizations dedicated
to a specific GID and ERN-ITHACA. To ensure a representative sample, the
socio-demographic characteristics of the participants will be checked.
There is currently no established guideline for determining the optimal
sample size for a Delphi survey (45, 46). The Study Management Group will
aim at including 60 participants in the Delphi survey in order to represent
the GID population as best as possible, ensuring the representation of
20 individuals with GID, 20 caregivers, and 20 experts. The pilot generic
core PRO set will be presented in the Delphi survey. The survey will be
kept as concise as possible. Additionally, participants, especially affected
individuals, will have the option to complete the survey at multiple times
to prevent overburdening. The Delphi survey will first be pilot-tested with
one member of each participant group to ensure that the survey is clearly
understandable.
3
Round one
In the first survey round, PROs will be prioritized. The pilot generic core
PRO set will be presented to participants, including a list of excluded PROs
or other outcomes along with the reason for their exclusion. Participants
will be asked to determine why a PRO is important enough to be included
in the generic core PRO set, or why a PRO should be excluded: response
options will be ‘Yes’, ‘Unsure/I do not know’, and ‘No’. They may also provide
a rationale for their decision, respond to the proposed conceptualization of
the PROs to ensure that no shared experiences are overlooked, and will be
asked for additional PROs.
The ‘70/15%’ consensus definition (i.e., including an outcome in the COS
when at least 70% of participants score an outcome as ‘very important’
and less than 15% as ‘not important’), which is described by Williamson
et al. (2012) (47), has previously been used by other COS developers (48-
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