Reliability and validity testing of the ASSIST functional performance index

Area of Science:

• Assistive Technology
• Rehabilitation Engineering
• Disability Studies

Background:

• Persons with physical disabilities (PwPD) can benefit from Mainstream Smart Home Technologies (MSHT) as Assistive Technology (AT).
• A validated tool is needed to assess PwPD's needs for MSHT and measure the impact of AT service delivery models.
• The ASSIST Functional Performance Index (AFPI) was developed to address this need.

Purpose of the Study:

• To conduct reliability and validity testing of the AFPI for PwPD.
• To evaluate the AFPI's utility as an assessment tool and outcome measure for MSHT.

Main Methods:

• The AFPI, comprising 46 items across functional domains, was administered twice to 22 PwPD (median 4-day interval).
• Test-retest reliability was assessed using the Intraclass Correlation Coefficient (ICC, 3.1).
• Item analysis used weighted kappa coefficients; validity was examined by correlating AFPI scores with SCI-FI questionnaires.

Main Results:

• The AFPI demonstrated moderate to substantial agreement across most items.
• Good to very good test-retest reliability was found for overall AFPI scores.
• The AFPI showed good to very good validity as an assessment and outcome measure for MSHT.

Conclusions:

• The AFPI is a valid and reliable tool for assessing MSHT needs and impact in PwPD.
• The AFPI can aid in recommending and evaluating MSHT interventions.
• Further research with diverse populations is recommended to establish broader clinical utility.