The North Colchester Healthcare Centre, open from 7am until 10pm seven nights a week, has already had 2,629 visits in its first month, according to the DoH.
A £250m access fund was announced in 2007 to pay for a GP-led health centre in every PCT and 100 new APMS practices in under-doctored areas.
The BMA believes the imposed health centres will draw investment away from existing practices and services.
Mr O'Brien said: 'Centres like this one are opening up and down the country, complementing services provided by existing practices and are already proving popular with patients.
‘The North Colchester Healthcare Centre will offer any member of the public the greater choice and flexibility they want, being able to see a doctor or nurse between 7am and 10pm, seven days a week, while still remaining registered with their own GP or they can choose to register at the centre if they find it more convenient.'
Last month GP newspaper reported that the latest polyclinic to open in London has attracted 1,000 visits in its first month.
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