Differences in referral rates from general practice

There are many unexplained differences in the rates at which general practitioners make referrals to other medical specialists. This study investigated 17,586 referrals from 141 general practitioners to specialists in seven specialties in Ringkjøbing county in Denmark. As an expression of the referral rate, a referral index was estimated for every general practitioner. The referral index was the number of referrals to the specialist per 1000 patients per year, including children, standardized for age and sex to the average population in Ringkjøbing county. The following six variables were evaluated in relation to the referral index: specialists in the local area, doctors per practice, consultations per general practitioner per year, patients registered, consultations per 1000 patients per year standardized for age and sex, and supplementary procedures per consultation. Stepwise multiple regression analysis was used. The study showed that the referral index rose both with a better access to specialist and with an increasing number of consultations per practitioner per year. The referral index fell with increased numbers of patients registered. No correlation was found between the referral index and number of supplementary procedures per consultation, number of doctors per practice and number of consultations per 1000 patients per year.