Initial Validation and Reliability of the CDKL5 Deficiency Disorder Hand Function Scale (CDD-Hand)

Area of Science:

• Genetics and Neurology
• Clinical Outcome Measures
• Pediatric Neurological Disorders

Background:

• CDKL5 deficiency disorder (CDD) is a severe neurodevelopmental condition.
• Early-onset epilepsy and developmental delay are hallmarks of CDD.
• Validated outcome measures are crucial for advancing CDD research and therapeutic development.

Purpose of the Study:

• To adapt the Rett Syndrome Hand Function Scale for CDD.
• To evaluate the feasibility, acceptability, content validity, and reliability of the adapted scale.
• To establish a reliable tool for assessing hand function in CDD patients.

Main Methods:

• Modified the Rett Syndrome Hand Function Scale based on expert and patient group consultations.
• Collected video data of hand function from 86 children with CDD.
• Assessed intra- and interrater reliability through video coding by two researchers.

Main Results:

• The adapted scale, named CDD-Hand, was developed with input from specialists and a consumer group.
• Data from 86 families provided initial evidence of the scale's validity and reliability.
• The CDD-Hand scale demonstrated suitability across various ages and functional abilities in CDD.

Conclusions:

• The CDD-Hand scale is a feasible and reliable measure for assessing hand function in CDKL5 deficiency disorder.
• This validated tool can support future clinical trials and therapeutic interventions for CDD.
• The adapted scale shows potential for broad application in the CDD population.