Authors' reply

We wholeheartedly agree with Dr Sanderson's conclusion that this study provides ‘a useful starting point for future discussion and research’. Clearly, the number of assessed patients was small as was the number of clinician-raters. We acknowledge these points in our discussion and conclude by recommending other large studies using patients from real-life clinical settings. We also agree that perception of ‘normal’ behaviour would vary according to nationality and this might have very real significance when assessing the mental state of an individual. This warrants further research.

Drs Sanderson and Reed both comment on the lack of socio-demographic data on the rating clinicians but unfortunately these data are not available. We disagree with Dr Reed's assertion that we are required to make the assumption that the groups are similar in all respects except culture. We state clearly that ‘we cannot exclude the possibility that other factors, in addition to cultural background, may have influenced these results’, and we go on to prescribe potential confounding influences, including age, gender, psychiatric training, years of experience, etc. Similarly, Dr Reed's suggestion that we minimised the implications of these difficulties is unfounded; in fact, we highlight the possibility that multiple factors, including cultural biases, might affect the accuracy of scores on the Young Mania Rating Scale between clinicians from different countries. It is highly probable that similar variability will be present when this rating scale is used in routine clinical practice by clinicians from diverse cultural backgrounds.

Notwithstanding the preliminary nature of our study and the methodological considerations discussed above, we believe our data support the suggestion that cultural background influences the interpretation of manic symptoms when using the Young Mania Rating Scale.