Dear Editor,

We read with interest the recent report by Barry and Murray on unregistered visual impairment. It is important to note, however, that this paper relates to registration instigated by completion of BD8 certificates. In September 2003, Stephen Ladyman, the then Health Minister, Department of Health, announced changes to the process of registration, referral and identification for visual impairment in England stating that the BD8 was trying to do too much. The BD8 certificate was replaced by the Certificate of Visual Impairment 2003 in November 2003 and two referral letters were introduced for use by eye clinics and high street optometrists to alert social services to the needs of people with vision impairments in advance of certification. The Welsh Assembly Government is reported to be awaiting final revisions of the forms before deciding whether this approach will be adopted also in Wales.

A further issue worth consideration is that any study that attempts to assess coverage of certification by application of certification criteria to visual status at one point in time will detect under-registration and "inappropriate" registration. Measures of visual function show variability – visual acuity can fluctuate greatly in an individual with diabetic eye disease and the point at which someone becomes certifiable due to visual field loss in glaucoma is not easy to determine. Patients need time to come to terms with their loss of vision and consultants need time to determine whether an individual is certifiable. One should not underestimate the distress faced by an individual when told that their condition is certifiable for registration as blind or partially sighted.