This manuscript reports the design of a multisource surveillance study of contact lens-related microbial keratitis in Australia and New Zealand. It describes and evaluates a new combination of techniques not previously used in ophthalmic epidemiology, intended to deliver a more robust methodology appropriate to detecting cases of contact lens related microbial keratitis in the light of increased community management of this condition.
Ophthalmic practitioners in Australia and New Zealand were surveyed 6 times over a 12 month period to detect cases of contact lens-related microbial keratitis. Case detection involved both active and passive surveillance, Internet reporting to capture whether or not cases had been seen during the reporting period and audit of major ophthalmic centres.
Good response rates were obtained and maintained using this approach, with an overall participation rate of 95.8% (711/742) of ophthalmologists. Internet reporting was used by 17% and 31% of practitioners in Australia and New Zealand, respectively. However active follow up was required to elicit responses from 72.5% and 63.1% of practitioners, respectively. Twenty-five percent of cases were captured through hospital audit and 33% of cases were managed exclusively in the community.
Active surveillance was essential to maintain response rates. The use of web based reporting and communication via the Internet facilitated data capture. One third of cases were managed exclusively in the community, which supports the surveillance of all ophthalmic practitioners. An additional recommendation to facilitate studies of this type would be the establishment of a national ophthalmic surveillance unit.