In order to improve the quality of the PGD and CU retrospective measures which have the potential for recall bias and telescoping effects (56), the interview utilized a Life History Calendar format developed by Thornton (57). This method has been empirically shown to improve the accuracy of retrospective reporting by providing multiple cues to improve the chances of accurate recall (57, 58). This makes the task more akin to the accurate and well-retained process of recognition than to the less reliable task of free recall.
