Table 2.

Definitions and interpretations of acceptability and scale-up components

Component	Definition	Interpretation/Application
Acceptability [1]
Burden	“the perceived amount of effort that is required to participate in the intervention”	Depictions of workload burden associated with STI POCT
Self-efficacy	“The participants confidence that they can perform the behaviour(s) required to participate in the intervention”	Competence/confidence in operating and implementing STI POCT
Perceived effectiveness	“The extent to which the intervention is perceived as likely to achieve it’s purpose”	Effectiveness of STI POCT compared with standard pathology/existing STI test-and-treat pathways
Scale up [2]
Compatibility	“how well the intervention fits with the systems, services and practices of the new environment or setting”	Broader health systems, operations, and clinics within which STI POCT is being implemented
Reach	“the level of contact with or individual participation of an intended target population in an intervention”	Patient engagement for implementation of STI POCT