We read with interest the article by Abbasi-Ghahramanloo et al, shedding light on the relationship between risk-taking behaviours and attention deficit and hyperactivity disorder (ADHD) in Iranian workers.1 The study identified 4 latent classes from low to high-risk, finding that 6.6% of the workers showed behaviours related to moderate or high-risk classes. Conclusions drawn also stated that a diagnosis of ADHD increased the chance of falling into the moderate and high classes, consistent with the core symptoms of ADHD and exhibition of impulsivity, inattention and hyperactivity that go hand-in-hand with risk-taking behaviour. We thank the authors for adding to a growing pool of knowledge encompassing ADHD and the likelihood of partaking in risk-taking behaviours. Here, we would like to offer some opinions on the study.The authors state in their methods section that ADHD was measured using the Conner’s Adult ADHD Rating scales (CAARS) 30-item questionnaire, with a score of >15 considered to show ADHD.1 This scale was used to “diagnose” workers with ADHD, and conclusions were drawn based on this questionnaire, such as comparison of ADHD prevalence. Typically, CAARS is used as a screening tool for ADHD and is not validated for diagnostic purposes,2 nor does it encompass any form of recommended measure for diagnosis of ADHD.Because of this, we feel that the data on the “prevalence” of ADHD in these Iranian workers cannot be compared to the other studies referenced looking at ADHD prevalence, for example, in prisoners. The latter paper used a clinical interview based on the DSM-V criteria for ADHD, and a psychiatric interview alongside an ADHD screening questionnaire.3 This method would be more in line with recommendations for diagnosing ADHD, and therefore more reliable data to be compared to other studies. Additionally, a recent meta-analysis by Young et al showed that the prevalence of ADHD in jails is five to tenfold more than that of the general population,4 so it could be seen as imbalanced to compare the prevalence of ADHD in workers and prisoners.The second study referenced looks at the presence of ADHD “symptoms” in university students, defined by CAARS, rather than diagnosis.5 This paper has more similarities to Abbasi-Ghahramanloo et al’s methods section and therefore statistical comparison between the two papers is more appropriate. We would therefore urge future research to ensure there is clarification between formal diagnosis of ADHD and presence of ADHD symptoms when comparing statistics from previous studies and make this distinction clear in their methodology.