Potential Barriers and Challenges

The panel of world-leading experts that contributed to the content of this Toolkit thought that these are some of the most important potential barriers or challenges relating to ensuring protocol fidelity and the availability of appropriate outcome measures.

protocol fidelity

• Maintaining good study compliance can be a challenge in an ID trial.
• It can be challenging to ensure that caregivers follow the intervention protocol.
• People with ID may refuse to attend an intervention or provide data on a given day due to difficulties tolerating procedures.
• Cognitive or communication difficulties in participants may lead to dosing errors or fidelity problems.
• Retention rates can be low, missing data rates high.

outcome measures

• Many outcome measures do not have reliability and validity in the ID populations.
• Self-report measures are not always reliable when participants have communication, information processing difficulties. 
• Obtaining independent, self-report data can be challenging as support staff often provide input into data collection. 
• People with ID may be hyper-sensitive to touch or sound and therefore extensive feasibility studies may be needed for the use of equipment or devices. 
• Subjective self-report outcome measures which use visual analogue scale scales can be confusing. 
• There is a lack of ID-specific outcome measures. 
• Mainstream adult cognitive assessments may not be appropriate given the ability levels of the participants, and can lead to ceiling/floor effects. 
• Participants’ anxiety levels can influence data collection.