Background: This study reviews 33 years of research into referrals made by optometrists, estimates mean referral rates and seeks to interpret what they mean.
Methods: A search of the medical and optometric literature, 1961-1993, disclosed all reports on referrals by optometrists. Techniques of meta-analysis were employed to rationalize results from various research designs. Principal variable: percent of patients referred by optometrists to 1) ophthalmologists and 2) all providers. Mean referral rates were estimated by log-scale weighting and computed separately by type of practice. Also reviewed: referral rates by eye condition and anatomic site.
Results: We found 15 research studies in which referral rates were indicated or could be inferred. On average, optometrists referred 3.83 percent of their patients to ophthalmologists; 5.50 percent to all providers. Cataract and glaucoma were the most common conditions referred; anterior eye and retina the most common anatomic sites.
Conclusions: No time trend was apparent. Referral rates varied by type of practice, with VA clinics high, HMOs and teaching clinics low, and private practices intermediate. Optometrists in private practice appear to be referring patients at rates consistent with referrals by optometrists who practice in more managed environments.