Page 37 - Let them speak Towards a patient reported outcome measure set for

Outcomes and instruments
or when it was not further specified. Otherwise, terminology for specific
behavior was reported, such as ‘repetitive behavior’. When version of the
outcome measurement instrument was specified, information is provided
in the Supplemental tables when reported by the authors of the included
clinical studies. Due to limited reporting and the large number of different
instruments used, numbers corresponding to the outcome measurement
instruments were used regardless of different versions.
Outcome measurement instruments were classified based on the
reported outcomes and information provided in the articles using a
conceptual model of health outcomes from Valderas and Alonso, which
is a combination of the classification system of Wilson and Cleary and the
International Classification of Functioning, Disability and Health [Figure
1(b)].12,36 Domains included symptoms, physical function, mental function,
social function, general health perceptions, and HR-QoL. Additionally,
cognitive function was included as a separate domain to better distinguish
mental health domains, considering the target population.
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Results
Of 4,507 identified citations, 312 studies met the inclusion criteria, with 251
research articles and 61 trial protocols in registers.
Study characteristics, population, interventions, methodology
Study populations differed across the studies, including heterogeneous
populations with ID of unstated etiology (n=143, 46%), GNDs (n=135, 43%),
and neurometabolic disorders (n=34, 11%). Specific genetic or metabolic
diagnoses that were included are presented in Table 1.
Sample sizes of identified trials ranged from 1 to 452 (median=40)
participants. Interventions included drug (n=123, 39%), diet or supplement
(n=14, 4%), and non-drug interventions such as behavioral interventions
(n=175, 56%). Randomization was used in 224 (72%) of the studies. Studies
were not blinded (n=155, 50%), single-blinded (n=10, 3%), double-blinded
(n=85, 27%) or blinding was unclear (n=62, 20%).
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