How effective is the referral chain for diabetic retinopathy?

Despite the availability of effective photocoagulation treatment, diabetic retinopathy remains the main cause of blindness in persons aged between 20 and 64 years. We have examined the effectiveness of the referral chain for retinopathy by auditing medical records for a representative sample being 226 diabetic patients (35% of attenders) referred to a special photocoagulation clinic. Patients were classified as 'late' or 'not late' by using an algorithm which accounted for the state of retinopathy at referral and the previous frequency of eye examination. Forty-four patients (19%) were considered to have been referred late. These were mainly younger onset patients, aged between 30 and 40, and not attending a diabetic clinic. Patients not attending any other outpatient clinic were 27 times more likely to be referred late.