Page 142 - Let them speak Towards a patient reported outcome measure set for

Chapter 6
individuals, caregivers, and experts were provided with an information
letter outlining the purpose of the study (i.e., reaching consensus on the
most relevant PROs). Although the study invitation specified the eligibility
criteria, the research team also verified eligibility after application using
participants’ sociodemographic information.
Survey
The pilot generic core PRO set, including the conceptualisation of each
PRO, was presented in the Delphi survey. The Delphi survey for individuals
with GID and caregivers was provided in Dutch, whereas the survey for
experts was provided in English. The survey for individuals with GID was
written in easy-read language, using simple words and short sentences.
The survey was pilot-tested by one member of each participant group (i.e.,
by an individual with GID, caregiver, and expert) to ensure that the survey
was clearly understandable and easy to complete within the predefined
time span. The survey response options were also tested to ensure they
adequately reflected participants’ ratings. The following adjustments were
made after the pilot-test: the conceptualisation of each PRO was displayed
immediately after the PRO, a concluding sentence was added at the end
of the survey, and the time span of the survey for individuals with GID was
adjusted to 1 hour instead of the earlier set time span of half an hour. The
survey was distributed to the participants through an online web application
(Castor EDC). The Delphi rounds took place between November 2023 and
April 2024. Participants were given 2 weeks to complete each Delphi round,
and received two reminders to complete the Delphi round after 1 week and
after 2 weeks.
Delphi rounds
Round one
When opening the first survey, participants were shown an instruction
form, which also included a link to the list of the excluded PROs and other
outcomes along with the rationale for their exclusion. The first survey
consisted of three parts. In the first part, demographic information (e.g.,
level of intellectual functioning of the affected individual, profession of the
expert) of the participants was gathered. In the second part, the pilot generic
core PRO set was presented to the participants. Participants were asked to
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