Generalizability Considerations of Intervention Studies

Recruitment siteWere participants recruited from a clinic, the general population, an opt-in from mobile network operator service, or a promotional advertisement?
Enrollment eligibilityWere inclusion/exclusion criteria generalizable to a larger population (e.g., mobile phone ownership was not required to participate in study)?
EquityWere study findings equal across all subgroups? Did interventions reach marginalized populations? Were there trends in sharing mobile phones across some populations, which could have mediated effects?
Follow-up lengthAt what time point was the efficacy of an intervention assessed?
Target denominatorWas the denominator for the target population a known entity?