A method includes: performing a scanning measurement of a female thread along first and second axes extending along a center axis of the thread and opposed to each other across the center axis; determining characteristic values of the thread from contour data of the thread obtained through the measurement; obtaining the contour data including first contour data associated with the first axis and second contour data associated with the second axis by performing the measurement; detecting a thread displacement along the center axis between a crest associated with the first axis and a crest associated with the second axis at each of first position and second position on the center axis; calculating inclination and deviation of the first and second axes from the thread displacements detected at the first and second positions; and adjusting an attitude of the thread for the measurement to eliminate the inclination and deviation.