Page 92 - Let them speak Towards a patient reported outcome measure set for

Chapter 4
Discussion
This review provides a comprehensive overview of PROs used for
individuals with GID by identifying PROs used in clinical trials and PROs
included in condition-specific COSs. We identified 66 different PROs used
in clinical trials, which referred to 13 unique PROs, and 22 different PROs
included in condition-specific COSs, which referred to 14 unique PROs.
Overlap existed between the 13 unique PROs used in clinical trials and
the 14 unique PROs included in condition-specific COSs: after integrating
these PROs, only 18 unique PROs remained, which were classified within a
conceptual framework. The most used PROs were quality of life, perceived
health, cognitive functioning, anxiety/stress, and depressive symptoms.
Overlapping PROs
A myriad of PROs is used for GID. This diversity of PROs may arise due to
the heterogeneous phenotype of GID, with a multitude of treatment targets
inherent to syndromic disorders, posing a challenge on selecting relevant
PROs for care and research purposes. However, even though various
PROs are used for individuals with GID, considerable overlap existed
between these PROs. This overlap arises due to various terms used for
the same PRO (e.g., ‘communication’ and ‘speech’), and the utilization of
multidimensional PROs encompassing multiple domains (e.g., ‘anxiety and
depressive symptoms’). This results in an excessive number of PROs being
used for GID, hampering the aggregation and comparison of PRO data both
within and between various genetic subgroups.
One potential explanation for the overlap in PROs could be the presence of
shared comorbidities among different GID subgroups as well, such as autism
(7), epilepsy (6), and sleeping disorders (21). These shared comorbidities
may result in similar PROs, such as communication, pain, and sleep. On the
other hand, it might also be possible that different clinical manifestations still
lead to the same PROs. Fundamentally, all individuals desire to experience
well-being and optimal functioning, such as living without symptoms (e.g.,
pain or fatigue), engaging in activities, and participating in society. This
desire of well-being and optimal functioning can be affected by different
clinical manifestations. For instance, Parkinson’s disease in chromosome
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