The implementation of e-Health initiatives aimed at improving medication adherence has shown limited success. This may be attributed to inadequate participant selection in evaluation studies. The objective of this evidence-based commentary is to examine the inclusion criteria of participants in e-Health interventions for medication adherence. In May 2021, we identified two systematic reviews, encompassing a total of 44 randomized controlled trials (RCTs) evaluating e-Health interventions for medication adherence. These interventions were aimed to diabetes (n=10), immunosuppressive therapy (n=6), and cardiovascular diseases (n=29). Participants in interventions utilizing digital apps had a lower mean age compared to those using telephones (53.9 ± 7.5 years vs. 63.4 ± 6.3 years). Most papers (91.0%) did not report participants' level of digital literacy, and educational background was only mentioned in 57.8% of the studies. Exclusion criteria associated with age, education, health conditions, were identified in the assessment of e-Health interventions, while digital literacy was seldom assessed. It is recommended incorporating the assessment and reporting of digital literacy into participant selection procedures in RCTs to address the digital divide and obtain more accurate information regarding the efficacy of e-Health interventions. Keywords: Medication adherence, e-Health evaluation, digital divide, health inequities, digital health