Figure 2From: Dementia trials and dementia tribulations: methodological and analytical challenges in dementia research Methods of assigning dementia diagnosis for clinical research. Differing methods of assigning the dementia outcome are described in terms of the time and effort required to make the diagnosis (x-axis) and the external validity of that diagnosis (y-axis). The positions are illustrative only and designed to show the 'trade off' between effort and validity. In assigning validity we assume that expert clinical assessment is the reference standard; hence, neuropathological assessment requires substantial time/effort but validity is relatively low.Back to article page