The study concludes by assessing the significance of the historical development of the Table of the Forms, its use within asylum statistics on psychological diagnosis and the legacy left on mental health statistics. This study has attempted to understand how the principal representative body for asylum medical superintendents in Britain developed psychological diagnostic concepts, and how the debates surrounding the Table of the Forms were motivated by its use in asylum statistics. The debates contained in this study constitute a crucial chapter in the history of the classifications used by the fledging British psychiatric profession, one which has been overlooked by historians of psychiatry and which had left a significant gap in scholarship on the history of classification. In approaching these questions through an examination of the fundamental categories used to gather the data of insanity, and placing them in relation to larger systems of health data collection that came to interest population research, this volume has linked the history of psychiatric classification to that of public health administration, governmentality and population control. The case of the Table of the Forms shows how classification and standardisation are linked to the development of data collection frameworks, and broader shifts towards statistical understandings of mental health.