We would like to thank Dr. Sachdev for his interest in our study. We concur with his argument that traumatic brain injury (TBI) is a significant risk factor for psychosis that deserves further study. Studies of monozygotic twins report that the concordance rate for schizophrenia is roughly 50%.^R446171 This would suggest that environmental factors are also important. Thus far much of the attention in environmental factors has focused on birth complications and illness or maternal stressors during gestation.^R446171 The size effects for these factors, however, are relatively small (between 2 and 3).^R446171 Results from Dr. Sachdev's study as well as ours would suggest that TBI may be another significant risk factor for persons with and without a genetic predisposition for schizophrenia.^{R446172,R446173} Indeed there is evidence that many psychiatric patients have sustained TBI within one year prior to hospitalization.^R446174 Moreover, in many other cases a prior TBI is undocumented in the medical chart.^R446174 We hope that both studies will motivate further investigations into the relationship between traumatic brain injury and psychosis.