A central file would no doubt allow citizens to be informed of the fact that this or that department or organization is using their data, if they were asked for that authorization in order to provide services. For instance, the Canada Revenue Agency could ask for the authorization to access a person's central digital file to solve a problem. Currently, Canadian citizens do not know which departments consult their existing digital data.
I believe that this data belongs to individuals and that they should be aware of the fact that an organization is doing research on them.
Do you think it would be legitimate that the individuals in question ask to be kept abreast of the fact that a department is examining their digital data?