Relevance of Personal Details in Job Applications
In regard to a job applicant, please tell me what relevance family details, height, weight, blood group, etc., have on the potential candidate's ability to do the job. I am very curious about this.
Quite apart from the fact that asking these sorts of questions would be illegal in many other countries, asking for this sort of information is a waste of time and energy. Focus on the skills, ability, and experience of the candidate to do the job. His or her blood group, for example, has no bearing on the ability to sell widgets, process a payroll, clean hotel rooms, code iPhone apps, cook a 10-course banquet for 500 people, or sweep gutters.
There might (and it is a BIG might) be a need to request a small amount of personal information after the candidate has been offered the job and they have accepted and started work. You certainly don't need it beforehand.