Faculty Mentor

Thomas R. Shaffer


Cancellation tests are simple instruments that have traditionally been used to study sustained attention. Common formats follow a test pattern in which rows of letters symbols or numbers are randomly interspersed with designated targets. Test participants are generally asked to identify targets while ignoring similar non-target distracter items. In the current study we present normative data on a new cancellation instrument developed at SDSU. We present guidelines for administration, as well as normative data on omission errors, commission errors, mean target hit rates, processing speed performance, and test-retest reliability for 102 undergraduate participants in the 18-25 year old age range. Statistical analysis suggests that the NIMH-SDSU Letter Cancellation Protocol has high test-retest reliability, but is also susceptible to practice effects when subsequent administrations occur within 5 weeks.

Included in

Psychology Commons



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