the us national institute on aging currently funds an intervention testing programme, whereby investigators nominate compounds (based on specific molecular aging theories) to have evaluated with respect to their effects on lifespan and age-related biomarkers in outbred mice. previous age-related testing in mammals has proved largely irreproducible, because of small numbers of animals and lax mouse husbandry conditions. the intervention testing programme aims to address this by conducting parallel experiments at three internationally recognised mouse aging-centres, the barshop institute at uthscsa, the university of michigan at ann arbor and the jackson laboratory.