Behavioral forecasts do not improve the prediction of future behavior: a prospective study of self-injury

Clinicians are routinely encouraged to use multimodal assessments incorporating information from multiple sources when determining an individual's risk of dangerous or self‐injurious behavior; however, some sources of information may not improve prediction models and so should not be relied on in such assessments. The authors examined whether individuals' prediction of their own future behavior improves prediction over using history of self‐injurious thoughts and behaviors (SITB) alone. Sixty‐four adolescents with a history of SITB were interviewed regarding their past year history of SITB, asked about the likelihood that they would engage in future SITB, and followed over a 6‐month period. Individuals' forecasts of their future behavior were related to subsequent SITB, but did not improve prediction beyond the use of SITB history. In contrast, history of SITB improved prediction of subsequent SITB beyond individuals' behavioral forecasts. Clinicians should rely more on past history of a behavior than individuals' forecasts of future behavior in predicting SITB. © 2008 Wiley Periodicals, Inc. J Clin Psychol 64:1–11, 2008.