Development and validation of the deep brain stimulation impairment scale (DBS-IS)

Area of Science:

• Neurology
• Neurosurgery
• Medical Device Technology

Background:

• Subthalamic nucleus deep brain stimulation (STN-DBS) significantly impacts Parkinson's disease (PD) motor and non-motor symptoms.
• Existing quality of life assessments inadequately capture STN-DBS-specific impairments.
• A need exists for a specialized tool to measure STN-DBS-related challenges.

Purpose of the Study:

• To develop and validate a novel questionnaire for measuring STN-DBS-related impairments.
• To create a reliable and valid instrument for assessing both motor and non-motor deficits associated with STN-DBS in PD patients.
• To facilitate better patient follow-up and comparative studies.

Main Methods:

• The development involved semi-structured interviews, pilot testing, and two multicenter surveys.
• Principal Component Analysis (PCA) and exploratory factor analysis were employed for item reduction and factor determination.
• Reliability (internal consistency) and construct validity were rigorously examined.

Main Results:

• The final (STN-)DBS Impairment Scale (DBS-IS) comprises 22 items across six factors: postural instability/gait, cognitive impairment, speaking problems, apathy, impulsivity, and device-related difficulties.
• The scale demonstrated high reliability (Cronbach's alpha 0.71-0.90) across all subscales.
• Strong construct validity was confirmed (r > 0.50, p < 0.001).

Conclusions:

• The DBS-IS is a reliable and valid instrument for measuring STN-DBS-specific impairments in Parkinson's disease.
• This questionnaire enables adequate follow-up of patients undergoing STN-DBS.
• The DBS-IS facilitates comparisons between patients with and without STN-DBS.