Responding to a written question from shadow health minister Jamie Reed (Lab, Copeland), junior health minister George Freeman said 1.8% of patients had registered a 'type one' objection to their data being shared outside their GP practice 'for purposes other than their direct care'.
The figures quoted by Mr Freeman are based on data from 61% of practices involved in the care.data pathfinder programme. He said that the majority of practices had opt-out levels in the range from 0.5% to 2.5%, although some practices had higher rates.
Read more: What next for care.data?
Early last year, plans to launch the care.data scheme - which would have led to extraction of a huge range of patient data from GP records - were put on hold.
The decision came after widespread concerns from patient groups and GP leaders that patients had not been adequately informed or consulted about the implications of sharing their information and about their right to opt out.
Last year the information commissioner also ruled that GP practices would not be in breach of data protection rules if they chose to impose a blanket opt out of all their patients from the care.data scheme.