Wearable smart devices have become ubiquitous in modern society, extensively researched for their health monitoring capabilities and convenience features. However, the "wearability" of these devices remains a relatively understudied area, particularly in terms of design informed by clinical trials. While wearable devices hold significant potential to enhance daily life, it is crucial to understand and validate design factors influencing their comfort, usability, and integration into everyday routines. This review aimed to evaluate the “wearability” of smart devices through a mixed-methods scoping review of the literature. By analyzing studies on comfort, usability, and daily integration, it sought to identify design improvements and research gaps to enhance user experience and system design. From 130 publications (1998-2024), 19 were included. The review revealed that most findings were qualitative, lacking the quantitative studies needed for validated design criteria. While qualitative data provides rich insights, the absence of quantitative research limits a comprehensive understanding of design issues in the field. This underscores the need for future studies to use quantitative methodologies to better assess and validate design guidance, improving wearability.