We thank the authors of ‘Critique of Bahorik et al. (Reference Bahorik, Newhill, Queen and Eack2013) – ”Underreporting of drug use among individuals with schizophrenia: prevalence and predictors” ’ (Van Dorn et al. Reference Van Dorn, Desmarais, Swartz, Young and Sellers2013), for taking the time to comment on our paper, as we have uncovered an error in the data coding that may have otherwise gone undetected. Although unrelated to the material in the critique, we are grateful for the opportunity to have re-examined our paper and to have caught an error. Our updated findings are qualitatively consistent with our original results, and the implications still suggest that the under-reporting of drug use is a concern in individuals with schizophrenia (Bahorik et al. Reference Bahorik, Newhill, Queen and Eack2013). Psychological Medicine is correcting the tables that were reported in error, and we hope that interested readers will consider our updated work.

Despite that the field has not achieved consensus on an ideal strategy for combining self-report and biological data, recent reports from the U.S. National Institute on Drug Abuse have indicated that such measures demonstrate optimal agreement when the time-frame covered by the self-report matches the biological window for detection (Donovan et al. Reference Donovan, Bigelow, Brigham, Carroll, Cohen, Gardin, Hamilton, Huestis, Lindbald, Marlatt, Preston, Selzer, Somoza, Wakim and Wells2012). Given that one of our aims was to examine the extent of agreement between self-reports and biological tests (Bahorik et al. Reference Bahorik, Newhill, Queen and Eack2013), employing measures that largely covered the same retrospective index was an important consideration to our study, and this methodological decision is supported by the current state of the evidence (Donovan et al. Reference Donovan, Bigelow, Brigham, Carroll, Cohen, Gardin, Hamilton, Huestis, Lindbald, Marlatt, Preston, Selzer, Somoza, Wakim and Wells2012).

The research that we conducted examined the extent of agreement between self-reports and biological tests for detecting drug use in individuals with schizophrenia, and then determined the predictors of drug use under-reporting (Bahorik et al. Reference Bahorik, Newhill, Queen and Eack2013). Given that there are strengths and weaknesses on every method that is used to assess for drug use in individuals with schizophrenia as well as limitations in the reliability and validity of measures of drug use collected from any source (e.g. Carey, Reference Carey2002; Ziedonis et al. Reference Ziedonis, Smelson, Rosenthal, Batki, Green, Henry, Montoya, Parks and Weiss2005; McHugo et al. Reference McHugo, Drake, Brunette, Essock and Green2006; Donovan et al. Reference Donovan, Bigelow, Brigham, Carroll, Cohen, Gardin, Hamilton, Huestis, Lindbald, Marlatt, Preston, Selzer, Somoza, Wakim and Wells2012), we are glad that this topic is receiving relevant attention. These weaknesses and limitations are reasons why we refrained from stating in our paper that there was a gold standard for collecting drug screen information. Nonetheless, our paper as well as others examining this topic, shed light on an important issue that affects a vulnerable population who essentially are the beneficiaries of this important area of research. We are glad that this topic is receiving the relevant attention it deserves.