Childhood maltreatment is linked to deleterious outcomes, whereby post-traumatic stress disorder (PTSD) has been identified as one of the most debilitating. This retrospective chart review examined whether self-reported affective measures (anxiety, depression, trauma), type of maltreatment (sexual, physical, emotional/verbal abuses), and demographics predicted a diagnosis of anxiety or PTSD among 169 children in a psychiatric inpatient hospital. Secondly, this study identified significant predictors of a PTSD diagnosis. Results indicated self-reported anxiety predicted a diagnosis of PTSD, while self-reported depression predicted PTSD only in maltreated children. Self-reported trauma predicted an anxiety diagnosis. PTSD risk variables including duration of stay, sex, self-reported anxiety, presence of sexual abuse, and presence of emotional/verbal abuse, showed sound sensitivity/specificity as predictors of risk for a PTSD diagnosis in an inpatient setting. Clinical implications are discussed.