Five years of surveillance.

service Email alerting the top right corner of the online article. T he British Ophthalmological Surveillance Unit (BOSU) has now been in existence for 5 years and has been actively involved in the surveillance of rare ophthalmological disorders for most of this time. It is now an appropriate time to consider what relevance it has to practising ophthal-mologists. The unit was set up to facilitate national surveillance of rare conditions that were either important for the public health or whose natural history or management was of clinical or scientific interest to the ophthalmo-logical community as a whole. The system of active case ascertainment is well known to be the most effective way of gathering information in these types of studies 1 and is used in a number of medical subspecialties in both the United Kingdom and abroad, most notably by paediatricians on whose model the unit is based. The BOSU currently actively surveys 1062 ophthalmologists. This number is made up of 828 consultants and senior lecturers, 156 associate specialists, and 78 ophthalmologists in the Repubic of Ireland, all of whom have clinical autonomy. Over the past 12 months 342 have maintained a 100% response rate by returning all report cards, while only 72 (7%) have failed to return a single card. The response rate has risen steadily since the inception of the unit and is now consistently more than 70%. There is still quite a marked variation in this response with South and West, Scot-land, and Northern Ireland regions being the best responders (over 85%), but even in other regions the rate has slowly improved. In the early days it was probable that unfamiliarity with the system, particularly the need to report even when no case had been seen, accounted for this. Our current reporting rate is now equivalent to that achieved by other surveillance units (neurological, gastroenterology), but we aim to improve this to a consistent rate of better than 90% in the future. This is what is routinely achieved through the Paediatric Surveillance Unit and is certainly possible in ophthalmology as shown by the current rate in Northern Ireland (>90%). In terms of output the unit has now aided 15 separate studies leading to seven peer reviewed publications and 24 reports to national meetings. Although this output is somewhat low, it is largely accounted for by the types of studies being run rather than from a lack of …