Frequency and strategicness of clock-checking explain detrimental age effects in time-based prospective memory.

= 17.24; 70% women) had to remember to push the ENTER key every 60 s while performing a two-back picture decision task. Together, relative and absolute clock-checking fully mediated the negative age effect on TBPM and explained 53.6% of the variance of TBPM performance. Complementary analyses revealed that both indicators were needed to fully mediate the effect of age on TBPM, but that strategic (i.e., relative) clock-checking was a stronger predictor of TBPM performance than absolute clock-checking. These results stress the importance of considering both aspects of clock-checking to investigate time monitoring in laboratory TBPM tasks and age effects therein, and provide avenues of intervention for improving older adults' TBPM. (PsycInfo Database Record (c) 2022 APA, all rights reserved).