Publication Date



Therapeutic Innovation & Regulatory Science



Neurodegenerative diseases cause developmental delays and loss of milestones in infants and children. However, scalable outcome measures that quantify features meaningful to parents/caregivers (P/CGs) and have regulatory precedence are lacking for assessing the effectiveness of treatments in clinical trials of neurodegenerative disorders. To address this gap, we developed an innovative, blinded strategy for single-arm trials with external controls using expert panel review of home video.


We identified meaningful, observable, and objective developmental milestones from iterative interviews with P/CGs and clinical experts. Subsequently, we standardized video recording procedures and instructions to ensure consistency in how P/CGs solicited each activity. In practice, videos would be graded by an expert panel blinded to treatment. To ensure blinding and quality control, video recordings from interim time points would be randomly interspersed. We conducted a pilot study and a pretest of grading to test feasibility and improve the final strategy.


The five P/CGs participating in the pilot study found the instructions clear, selected activities important and reflective of their children’s abilities, and recordings at-home preferrable to in-clinic assessments. The three grading experts found the videos easy to grade and the milestones clinically meaningful.


Our standardized strategy enables expert panel grading of developmental milestone achievements using at-home recordings, blinded to treatment and post-baseline time points. This rigorous and objective scoring system has broad applicability in various disease contexts, with or without external controls. Moreover, our strategy facilitates flexible, continued data collection and the videos can be archived for future analyses.


Rare disease, Home video recording, Developmental milestones, External control, Clinical trial endpoints, Natural history study

Included in

Neurology Commons



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.