There is a growing need for tools that can be used in clinical practice and research to determine the vision abilities of children with cerebral palsy (CP), as vision has a profound effect on functioning and disability. Vision is a complex construct in itself, and this study reports a method for conceptualizing "visual ability" as a measureable construct. Pre-existing assessments tool were subject to a two-phase process, whereby deductive content analysis linked items on the tools to the ICF-CY, while vision-specific "Activity" items were explored with inductive thematic analysis.  Using this approach, the researchers determined that existing assessment tools can measure vision across ICF-CY domains of Body Functions, Activities and Participation, and Environmental and Personal Factors. Additionally, items identified as vision-specific were defined as "how vision is used," forming the basis for the conceptualization of visual ability. Through thematic analysis, 13 themes that can be organized into 3 categories to reflect a child's observable visual behaviors were identified. In the future, these observable visual behaviors could be used to assess how vision is used in daily activities. Overall, the study was able to demonstrate an approach for explaining complex topics such as vision using language derived from the World Health Organization while building on the current state of knowledge.   Authors:  Deramore Denver B ,  Adolfsson M ,  Froude E ,  Rosenbaum P ,  Imms C . BMC Med Res Methodol. 2017 Mar 21;17(1):46. doi: 10.1186/s12874-017-0316-6.