[Self-Report Altruism Scale Distinguished by the Recipient (SRAS-DR): validity and reliability].

This study describes the development and evaluation of the Self-Report Altruism Scale Distinguished by the Recipient (SRAS-DR). The relationship between an actor and a recipient is important for evolutionary studies of altruistic behavior. However, the existing scale for Japanese undergraduates does not distinguish recipients of altruistic behaviors. We developed a new self-report altruism scale based on an evolutionary viewpoint. In Study 1, undergraduate students described their altruistic behaviors in daily life, which we classified according to the recipients (family members, friends or acquaintances and strangers). Then we chose 21 items (7 items for each recipient class) to construct the SRAS-DR by using exploratory factor analyses. In Study 2, we investigated validity and reliability of the scale. The scores were significantly correlated with other relevant scales as well as with behavioral indicators. Test-retest reliability was high. These results indicate that the SRAS-DR has acceptable reliability and validity, and can be used in evolutionary studies of human altruism.