Reliability and Validity of Prisoner Self-Reports Gathered Using the Life Event Calendar Method.

Data collection using the life event calendar method is growing, but reliability is not well established. We examine test-retest reliability of monthly self-reports of criminal behavior collected using a life event calendar from a random sample of minimum and medium security prisoners. Tabular analysis indicates substantial agreement between self-reports of drug dealing, property, and violent crime during a baseline interview (test) and a follow-up (retest) approximately three weeks later. Hierarchical analysis reveals that criminal activity reported during the initial test is strongly associated with responses given in the retest, and that the relationship varies only by the lag in days between the initial interview and the retest. Analysis of validity reveals that self-reported incarceration history is strongly predictive of official incarceration history although we were unable to address whether subjects could correctly identify the months they were incarcerated. African Americans and older subjects provide more valid responses but in practical terms the differences in validity are not large.