Eye test prices fell last year according to the Optical Confederation's annual Optics at a Glance data.
The average charge to patients for a private sight test was £21.30 for the year ending March 31 2010, compared to £23.05 during the prior year. Practice data excluded 'no charge', discounts and special offers.
The 30th annual edition of Optics at a Glance paper also found that 63 per cent of sight tests resulted in a changed or new prescription during the period, from 69 per cent in 2008-09.
NHS sight tests numbers in the UK increased 4.3 per cent to 14.7 million during the period, from 14.1 million last year, research showed.
It also identified a shortfall between the number of patients who are likely to be entitled to NHS domiciliary eye care and the number of patients receiving the service.
A spokesperson for the Federation of Ophthalmic and Dispensing Opticians said: 'Although the FODO survey does not record the reasons behind the [eye test price] decrease, common sense would suggest it is probably due to increasing competition on the high street.
'The increase in NHS sight tests could be due to a number of factors. A large proportion of people receiving NHS services are 60 and above, and so with a rising older population we would expect to see a rise in numbers year on year.
'There could also be an increase in awareness of the importance of regular sight tests and/or NHS eligibility. In addition, low costs of spectacles in some high street practices might also encourage some patients to access the service.'
Statistics for Optics at a Glance were drawn from a survey of FODO members, together with government figures and data from the Association of Contact Lens Manufacturers, College of Optometrists and General Optical Council.
The number of patients choosing contact lenses was found to be unchanged compared to the year before, at 6 per cent, the Optical Confederation reported. Meanwhile, 5 per cent of patients were referred to a GP or hospital, up from 4 per cent in 2008-09.
Other findings by FODO showed that the average interval between sight tests was 26 months, unchanged from the year before.