A method for an observational screening method or a drug screening method, includes the steps of providing an enclosure for at least one animal with outer sidewalls, preferably 4 outer sidewalls; providing temperature sensing device for sensing a body temperature of at least one animal and/or activity measurement device for measuring at least one parameter related to physical activity of at least one animal; sensing a body temperature of at least one animal and/or measuring at least one parameter related to physical activity of at least one animal; providing data processing device; and processing data related to body temperature and/or to the parameter related to physical activity.