“…Previous research has highlighted different areas of similarity, such as being in a similar geographical location, culture, employment status, marital status, age, and recency of childbirth, as contributors to peer relationship building [ 23 , 27 ]. Having similar experiences, however, seems to be one important aspect for successful relationships identified by many studies (e.g., [ 23 , 37 , 40 ]). Research on similarity-attraction suggests that surface-level (e.g., age, ethnicity) and deep-level (e.g., attitude, values) have impact on quality of social relation with peers and program adherence behaviours [ 60 , 61 ].…”