This study was designed to assess the appropriateness of current standardized checklists used to measure stressful life events in a noninstitutionalized population aged 65-74 years of age. Previous studies, sampling from a younger aged population, have demonstrated a temporal association between an increase in stressful life events and psychophysiological disease. Before stress can be studied as a precipitator of disease onset in the aged, it must be determined if the instruments designed to measure stress are reliable and valid for use with the aged. Specifically, the following questions were examined: (1) Reliability--Are the checklists reliable for use with this population? (2) Relevance--Are the checklists valid for use with this population? (3) Are these events considered to be stressful for this population? (4) Does the scoring system used influence the results? (5) Are the events included on the checklists events that occur in the lives of people aged 65-74? (6) Are there other events, not on the checklists, which are stressful for older people? The data base for this study consisted of responses from 185 subjects aged 65-74 years. Each respondent completed three standardized checklists designed to measure stressful life events and a demographic sheet which included provision for respondents to write any stressful event(s) that had occurred. Results were analyzed by subscale. As a result of this study it was determined that: (1) Reliability coefficients across subscales were not sufficiently large to warrant using these checklists with this aged population. (2) The three checklists were not valid for use with this aged population. (3) Respondents in this study perceived most events as being more stressful than did a younger age standardized group. (4) Standardized weights for the events should be assigned by people aged 65-74 years. (5) Stressful life events are different for people aged 65-74 years than for younger aged people. It was recommended that the checklists be revised for use with this age population. This revision includes modifying events on the checklist and having people aged 65-74 years assign standardized weights that reflect the stressfulness of the events.