It is difficult to determine potential confounders in this scenario without more information about the study and the specific association between age and contact patterns. However, some potential confounders that could influence the association between age and contact patterns in this study could include:
Employment status: If young adults in the study are more likely to be employed or have more social interactions due to their job, this could explain why they have a more active contact pattern.
Education level: If young adults in the study have a higher education level and therefore more social interactions with peers, this could contribute to a more active contact pattern.
Marital status: If young adults in the study are more likely to be single and therefore have more social interactions, this could explain why they have a more active contact pattern.
Health behaviors: If young adults in the study have different health behaviors, such as engaging in more risky behaviors or participating in more social activities, this could contribute to a more active contact pattern.
Location: If young adults in the study live in different geographical areas with different social norms and opportunities for social interactions, this could influence their contact patterns.