Despite the widespread use of distress screening instruments in cancer care, the reliability and validity of these instruments for a diverse population of cancer patients have not been well established. This is a systematic review of the conceptual and statistical equivalence of screening instruments of 148 psycho-oncology studies that included distress screening instruments. The findings indicate that screening measures of distress have comparable reliability, sensitivity, and specificity for White, Latino, and Asian samples. However, it is unclear if equivalent psychometrics are found among minority ethnic groups (e.g., African American) and immigrants within countries. Given the ethnic diversity among cancer patients and the lack of representation of this diversity in the current research, it is critical that researchers begin to include cancer patients of minority ethnic/racial groups in their samples so that health care providers can screen for distress with cultural sensitivity.