BackgroundProactive interventions for patients with mild cognitive impairment (MCI) are required. We aimed to determine the staff‐rated ability to provide post‐diagnosis support for patients with MCI at a medical centre for dementia and the related factors.MethodsWe conducted a web‐based survey on post‐diagnosis support for patients with MCI among healthcare personnel, such as mental health social workers and public health nurses (hereafter referred to as ‘staff’), in consultation and support roles at medical centres for dementia nationwide. The latent characteristic value for ‘staff's self‐rated ability to provide post‐diagnosis support to patients with MCI’, which was estimated using the one‐parameter logistic model of item response theory, was used as the dependent variable. Multivariate linear regression analysis was used to examine the factors associated with the dependent variable.ResultsWe conducted the study at 482 medical centres for dementia. We received responses from 162 participants, 158 of which were valid. We applied item response theory to 45 staff‐rated items regarding post‐diagnosis support for patients with MCI and found that item difficulty ranged from −2.56 to 1.02; 40 items had negative values and were deemed relatively easy. The staff‐rated ability to provide post‐diagnosis support was significantly higher for ‘The role in assisting patients with MCI is clear’ (P < 0.005), ‘A reasonable number of personnel is available to assist immediately after MCI diagnosis’ (P = 0.001), and ‘Collaboration with family physician available immediately after MCI diagnosis’ (P < 0.001).ConclusionsThe results of this study showed that staff rated their ability to provide post‐diagnosis support for patients with MCI as relatively easy. The staff‐rated ability to provide post‐diagnosis support to patients with MCI may be enhanced by increased availability of staff immediately after MCI diagnosis, clarification of staff roles, and collaboration with family doctors.