Final answer:
Direct and indirect costs should be included when conducting a study from a societal perspective.
Step-by-step explanation:
When conducting a study from a societal perspective, the costs that should be included are direct and indirect costs. Direct costs are the expenses that are directly related to the study, such as research materials and participants' compensations. Indirect costs, on the other hand, are the broader expenses that are not easily quantifiable but have an impact, such as the cost of lost productivity or the cost of social support systems.