IN POPULATION-BASED PREVALENCE SURVEYS, UNDETECted

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1 Community Screening for Eye Disease by Laypersons: The Hoffberger Program HARRY A. QUIGLEY, MD, CHAN KEE PARK, MD, PATRICIA A. TRACEY, BLA, AND IRVIN P. POLLACK, MD Accepted for publication Nov 14, From the Glaucoma Service and the Dana Center for Preventive Ophthalmology and the Departments of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland (H.A.Q., C.K.P., P.A.T., I.P.P.); Sinai Hospital of Baltimore, Baltimore, Maryland (I.P.P.). Supported in part by grants from the Aaron Straus and Lillie Straus Foundation, Baltimore, MD, the Hoffberger Foundation, Baltimore, MD, and the Local Initiatives Program of the Robert Wood Johnson Foundation, Princeton, NJ. Reprint requests to Wilmer 122, Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287; fax: ; PURPOSE: To describe the results of a communitybased eye screening program in Baltimore. DESIGN: Cross-sectional study. METHODS: This was a retrospective study of the results of screening both eyes of 5352 persons who presented at multiple community sites. The screening examination had eight risk factor questions, visual acuity measurement, and a screening field test and was carried out by technicians and lay volunteers. Screened persons (screenees) received a definitive eye examination at no out-of-pocket cost, transportation was offered, and inexpensive eyeglasses were provided if needed. The main outcome measures were the rate of appointment keeping and the eye diseases identified. Telephone interviews were used to assess reasons for missing appointments and satisfaction with visits. RESULTS: Screenees had a median age of 45 years, were 71% black, 59% female, and had estimated median annual family income of $24,000. Among 1331 screenees who scheduled a definitive examination appointment, 552 (41%) completed the visit. Data on definitive diagnosis was available in 480 out of 552 persons (87%). Reasons given for failing to come for definitive examination were: no appointment given (26%), forgot (20%), lack of transportation (9%), and lack of insurance coverage (6%). Of those who accepted a second visit date after defaulting, only 25% (41/167) appeared. Of 17 persons identified with glaucoma at screening, 4 had previously been diagnosed, but had ceased active care. CONCLUSION: After community screening for eye disease, efforts to provide definitive ophthalmic examination were only modestly effective. Failure of screenees to come for examination and loss to follow up were identified as serious problems. (Am J Ophthalmol 2002;133: by Elsevier Science Inc. All rights reserved.) IN POPULATION-BASED PREVALENCE SURVEYS, UNDETECted eye disease is common, even in developed countries with national health care schemes that provide care at no cost. Nearly half of those with glaucomatous optic nerve damage are undiagnosed in the developed world, while in developing countries, the rate of undiagnosed glaucoma ranges from 70% to 100%. 1 Even ocular diseases with symptoms that should be apparent to the affected person, such as cataract and diabetic retinopathy, are not diagnosed or cared for appropriately. 2,3 Screening outside the typical health care facility has been a frequent activity among nongovernmental organizations. Often, such programs use low technology equipment and are staffed by laypersons. 4 To our knowledge, the predictive power of this approach has not been evaluated by detailed examinations of large numbers of positive and negative screenees. In many programs, positive screenees are advised to seek eye care, but specific appointments are not given and minimal follow-up information is received. A community-based screening program for eye disease was carried out in Baltimore, Maryland, for 4 years using lay screeners. We provided incentives for participants to undergo definitive examination by offering visits at no out-of-pocket cost, transportation, and discounted cost for eyeglasses. Telephone interviews were conducted with those who did and did not come for definitive care. This report describes the screenees, presents the rates of appointment keeping, and the results of telephone interviews with screenees. Subsequent reports will detail the predictive power of specific screening strategies. METHODS THE HOFFBERGER PROGRAM FOR THE PREVENTION OF Blindness is a community-based vision screening program BY ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED /02/$22.00 PII S (01)

2 TABLE 1. Questions Asked at Screening 1. Are you over age 65? 2. Do you have a blood relative with glaucoma? 3. Have you ever been told you have glaucoma? 4. Have you ever been told you have diabetes? 5. Have you ever taken prescription eyedrops? 6. Have you ever had eye surgery? 7. Was your last eye exam more than 1 year ago? 8. Are you now receiving regular eye care? begun in Baltimore, Maryland, in 1996 and is funded by three charitable foundations. In this report, a retrospective review of cross-sectional data are presented to evaluate specific program outcomes. In particular, the outcomes of greatest interest were the proportion of screened persons (screenees) who came for definitive examination and what eye diseases they exhibited. Among nearly 13,000 screenees in the overall Hoffberger program, 5352 persons were screened in East Baltimore and definitive examinations were offered to this group at Johns Hopkins. These data comprise the present report. The data analysis was approved by the Joint Committee on Clinical Investigation of the Johns Hopkins School of Medicine and abided by the tenets of the Declaration of Helsinki. The Hoffberger program is a partnership between: (1) community organizations, including the Clergy United for the Renewal of East Baltimore; (2) Departments of Ophthalmology at Johns Hopkins University, Sinai Hospital of Baltimore, and University of Maryland; and (3) Penn Optical Co. Eye screenings were conducted at churches, senior housing complexes, community centers, and health fairs by trained teams consisting of at least one neighborhood health worker and one or more community volunteers. Neighborhood health workers were full-time employees who were trained in visual acuity and visual field testing. They organized and publicized screenings, recruited volunteers for the event, counseled positive screenees on scheduling of definitive eye care, and led training sessions for volunteers. Community volunteers underwent 6 hours of written and oral training in screening techniques and ocular diseases, including a practical test with screening instruments. They signed an agreement to participate in six screenings out of year. Clergy in neighborhood churches publicized the importance of preventive eye examinations and incorporated screenings into church activities. Seven neighborhood health workers and over 150 community volunteers were trained and certified. Methods were adapted from the Prevent Blindness America screening program. We used a questionnaire seeking information on eight risk factors for eye disease (Table 1). The majority of persons screened (screenees) were black and we did not use ethnicity as an independent risk factor question. Visual acuity was tested at distance with an ETDRS chart, typically at 6 m, in the two eyes separately with habitual eyeglasses. Pinhole correction was used if acuity was worse than 20 out of 30 in either eye. Binocular near visual acuity was tested with an acuity card at 14 inches with present eyeglasses. Finally, a screening visual field test was performed in each eye with better than 20 out of 200 vision. Initially, the Damato OKP test was used. 5 This was replaced during the second half of the program by the FDT screening test. 4,6 Referral for definitive eye examination was offered if any of the following criteria were met: (1) 1 positive answer to risk factor questions; (2) 20 out of 30 distance acuity despite pinhole or 20 out of 40 near acuity; (3) 1 missed point on either the Damato or the FDT field test in one eye. Additionally, we offered definitive examination to any screenee who requested an examination, thereby providing a convenience sample of screenees who had definitive evaluation without meeting any of the positive screening criteria. For those without an eye care provider, we provided a specific referral appointment to the nearest project facility (Wilmer Institute, Johns Hopkins [East Baltimore], Sinai Hospital of Baltimore [North Baltimore], or University of Maryland [West Baltimore]). Alternatively, we provided screening results to the eye care provider chosen by the screenee. We used several strategies in an attempt to increase attendance at definitive examinations. The need to undergo examination was encouraged by a neighborhood health worker or volunteer, who was a member of the community. Screenees were informed that there would be no out-of-pocket cost for definitive examination at our facilities if the cost exceeded their insurance coverage. Transportation to the examination was offered. Available times for examinations included night and Saturday clinic hours. Bifocal eyeglasses, if needed, were provided for $40 to those undergoing definitive examination. A standard form was used by ophthalmology residents who performed and recorded the definitive examination findings, including best corrected visual acuity, need for eyeglass correction, prescribed medical and out of or surgical treatment, and date of follow-up visit. The ophthalmologist provided a clinical diagnosis: normal examination, refractive error, or one of a list of ocular diagnoses. Refractive error was defined by referral criteria as distance vision worse than 20 out of 30 or near vision worse than 20 out of 40 that was correctable by spectacles. Glaucoma was diagnosed when the patient had one of the following in at least one eye: (1) a Zeiss Humphrey threshold field test with a glaucoma hemifield test result of outside normal limits or a PSD index probability value of P.5% or worse and an optic disk compatible with the field defect; or (2) a cup out of disk ratio 0.7 and nerve fiber layer atrophy, but without a visual field test performed. Glaucoma suspects had one or more of the VOL. 133, NO. 3 COMMUNITY SCREENING FOR EYE DISEASE 387

3 TABLE 2. Demographic Information on Participants Screened Offered Exam Had Definitive Exam Number 5,352 2, Mean age Median age n for age data 4,938 1, Race % n % n % n Black 70.6% % % 438 White 15.7% % % 34 Other 1.3% % % 4 Not given 12.5% % % 4 Gender Female 59.2% % % 267 Male 39.3% % Not given 1.4% % 6 0.2% 1 following: IOP 20 mm Hg, exfoliation, cup out of disk ratio 0.6, or a family member with glaucoma. A standard telephone interview was administered to those who completed definitive examinations and to those who failed to appear for scheduled visits (defaulters). Questions assessed the experience of those who completed care, including what diagnosis that they had been given and what recommendations for follow-up care that they remembered. For defaulters, we asked the reasons for failure to attend the examination and we listed their attitudes toward rescheduling a visit. Data were recorded on a Microsoft Access file and evaluated biostatistically on PC-based standard programs, including 2 and the Fisher exact test. RESULTS FROM 1996 TO 2000, DATA FOR 5352 SCREENEES IN THE EAST Baltimore program were available for analysis, representing 97.7% of the total of 5473 screenees. Of these, 3155 met one or more of the referral criteria. Our staff found that 2000 of these were not receiving regular eye care and were offered an examination within the program. A total of 1331 persons agreed to be scheduled for a definitive examination at the Wilmer Institute (25% of all screenees, 42% of those who met one or more screening criteria [Table 2]). The rest of the positive screenees either refused to schedule an appointment or stated that they preferred examination by another physician. While we attempted to obtain definitive examination data from these evaluations, there were too few for analysis. There were 552 screenees who completed the definitive examination at the Wilmer Institute (41% of all attempted referrals) and 480 of these had complete visit records for review (36% of referrals, 87% of definitive examinees). The demographic data for those screened, referred, and examined, respectively, are given in Table 2. In 1998, Baltimore City had an estimated population of 645,000 (United States Census Bureau), with 220,000 persons over age 45, 67% black, and 24% below the Federal poverty level. The screenees were similar to the Baltimore population in the proportion who were black (67.4%). Among screenees over 45 years of age, 60% were female, and 18.1% of screenees were over 65 years of age. Using 1990 U.S. Census data for median annual family income, we estimated a weighted average family income from the zip code of screenees. The weighted average was $26,148 per year for all screenees and $24,278 per year for those who underwent definitive examination. Median family income for the Baltimore Metropolitan Statistical Area was $42,206 and for Baltimore City alone it was $28,217 (U.S. Census data, 1989). Thus, our patients were poorer by this measure than the average city family. Fifty-six percent of screenees had not had an eye examination within the last year (3007 out of 5352) and only 26.5% identified a specific eye care provider (1416 out of 5352). The diagnoses assigned at definitive examination included 17 persons with glaucoma, 44 glaucoma suspects, 10 with diabetic retinopathy, and 3 with age-related macular degeneration. Those with an eye disease were less likely to have had an eye examination in the last year than all screenees or than those who had a definitive examination, but did not have eye disease (differences not statistically significant; Table 3). Of 1331 persons scheduled for a definitive examination, 779 did not appear for the visit (overall default rate for first visit, 59%). Of these, 236 were successfully contacted by telephone (30%). Many of those who could not be contacted were homeless, residents of temporary housing, had moved, or had no telephone. Hence, responders may have higher socioeconomic status than those not contacted. The most important reasons selected for defaulting on definitive examination were not receiving an appoint- 388 AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2002

4 TABLE 3. No Eye Examination Within Preceding 12 Months Percent Proportion All screenees 56.2% 3007/5352 Those with any eye disease 67.7% 176/260 Glaucoma with field loss 76.5% 13/17 Glaucoma suspect 65.9% 29/44 Retinal disease 64.3% 9/14 Difference between all screenees and those with any eye disease is borderline in statistical significance, chi square, P TABLE 5. Diagnoses at Definitive Examination Diagnosis Number (Percent) Refractive error % Cataract 71 15% Glaucoma suspect 44 9% Normal exam 23 5% Other 39 8% Glaucoma 17 4% Retinal diseases 14 3% Diabetes 10 2% Total 480 TABLE 4. Reasons for Not Attending Definitive Eye Examination (Telephone Interview) Answers Percent (Number) No appointment letter received 26% (49) Forgot to come 20% (38) Other 13% (25) No transport, need escort 9% (17) Work conflict 9% (16) Fear of cost 6% (11) Personal problem 6% (11) Sick 5% (10) Preferred another doctor 5% (10) Problem not believed serious 1% (1) Total 188 ment and not remembering to come (Table 4). Only 6% cited fear of the cost of the visit, confirming that we had successfully communicated that the visit would be free of charge. Each screenee who defaulted on the first definitive appointment was contacted by telephone and offered a second definitive examination, with a specific date given by telephone and followed up by a mailed reminder. Of these, 167 screenees out of 236 (71%) scheduled a second visit and none stated that they needed transportation assistance. All were reassured that there would be no out-of-pocket cost for the visit. Several months later, 62% of these (103 out of 167 persons) had either failed to come for the second scheduled visit (90 persons, 54%) or had cancelled it without rescheduling (13 persons, 8%). The visit was kept by 25% (41 persons) and 23 persons are presently listed as having a pending visit (14%). We successfully contacted for a telephone interview 218 screenees out of 480 (45%) of those who came for definitive examination. More than half reported no eye examination for more than 2 years before program screening. The prior examination was reported to have been conducted by an optometrist in 55% (103 out of 189) and an ophthalmologist in 42% (80 out of 189). Laypersons may have difficulty in distinguishing the professional credentials of eye care providers. Hence, we asked for the name or location of the previous examiner. Among these, 46% (38 out of 83) were names of optometrists practicing in Baltimore City or were facilities that have only optometric staff. Another 49% (41 out of 83) were names of known ophthalmologists in the community or were facilities in medical centers staffed by medical doctors. The remaining four names were not identifiable. The telephone interview identified possible factors that might prevent persons from seeking eye care, including lack of transportation, high cost, problem not serious enough, bad past experience with eye examinations, and conflict with work or family schedule. Over 74% (89 out of 120) listed cost of examination or lack of insurance coverage for eye care as the most important reason that they had not had more frequent examinations before our program. The most common clinical diagnosis for those undergoing definitive examination was refractive error, listed as the sole diagnosis after examination in 255 screenees out of 480 (53%) of persons at definitive examination (Table 5). Ophthalmologists indicated that 72% (343 out of 480) of examinees needed new glasses. At telephone interview, clients were asked if they were given a prescription for eyeglasses at the definitive examination and 68% (135 out of 198) stated that they had been given a prescription. The program provided glasses at a cost of $40; we found that 72% of those given a prescription did utilize the $40 eyeglass arrangement (65 of 90 responses to this question). Those who purchased these glasses were asked if the glasses were satisfactory or unsatisfactory. None chose unsatisfactory as the response. Among those who underwent definitive examination, the degree of monocular and binocular visual impairment and the rate of bilateral legal blindness was similar to that detected in the Baltimore Eye Survey population of black persons over age 40. 6,7 The prevalence of bilateral blindness was 0.6% (3 of 480 persons) and visual impairment (worse than 20 out of 60 in better eye) was 3.8% (18 out VOL. 133, NO. 3 COMMUNITY SCREENING FOR EYE DISEASE 389

5 TABLE 6. Comparison of Physician Diagnosis Codes and Patient Recall of Diagnosis Given Patient Report Physician Diagnosis Refractive Error Cataract Glaucoma* Diabetic Retinopathy Eyeglasses 90% (69) 25% (7) 50% (11) Cataract 46% (13) Glaucoma 27% (6) Diabetic retinopathy 25% (1) Other 8% (6) 21% (6) 18% (4) 50% (2) Total interviewed Total diagnosed Percent is the percentage of the total interviewees in each diagnostic group who correctly identified the diagnosis that was coded by the ophthalmologist at definitive examination. Thirty to fourty percent of each diagnosis group were successfully interviewed for this question. *Includes glaucoma and glaucoma suspect. of 480). Cataract accounted for two out of five persons with bilateral visual impairment and one out of three persons with bilateral blindness. The other two persons with bilateral blindness had macular degeneration. The diagnoses given to the 480 persons who underwent definitive examination could be grouped into 53% (255) with refractive error only, 42% (202) with an eye disease and 5% (23) with normal examinations and no need for eyeglasses (Table 5). Cataract and the combination of glaucoma and glaucoma suspect were most common, while fewer persons had retinal diseases. There were a variety of other diagnoses, including strabismus, trauma, disorders of the eyelids, and neurologic findings. Twenty-four percent (4 out of 17) of those with glaucomatous field loss and 5% (2 out of 44) of glaucoma suspects reported that they had previously been told that they might have the disease. Among those with diabetic retinopathy, only 3 out of 10 reported having an eye examination within the last year. In the telephone interview, those who had undergone definitive examination were asked to describe specific aspects of the visits, including what diagnosis the ophthalmologist gave them, what therapy was suggested, and when they were asked to return. This was matched against the data recorded by physicians at the visit. Of those asked to come back for a follow-up visit due to an eye disorder, 26 out of 43 (60%) of those asked to come back in 3 months (and successfully interviewed) correctly stated that this was the time for the next visit. The 4 to 6 month visit was correctly remembered by 64% (9 out of 14) and a 1-year visit interval was correctly recalled by 84% (26 out of 31). Subjects did not do so well in identifying what the physician had prescribed as treatment. Of 18 persons who were given prescriptions for medications, only 2 out of 10 of those interviewed (20%) correctly said they received instructions to take eye medicine. This was, however, higher than the 5% (8 out of 163) who said they received a prescription medicine, but were not coded as receiving drug therapy. Of 37 persons who were recommended to have a laser or surgical procedure, 3 out of 11 (33%) of those surveyed said that surgery was suggested. Physicians did not recommend surgery to 150 persons, yet 8 of these (5%) stated that surgery had been offered. We asked if the doctor had told the participant that he or she had an eye disease and, if so, what disease. If no name was immediately offered, the list of diagnoses used by our ophthalmologists was provided for the participant to use as possible choices (Table 6). Those interviewed who had only refractive error were 90% accurate in stating their diagnosis, while those with cataract as their clinical diagnosis were less accurate (46%), and only 27% of those interviewed who were coded as glaucoma suspect or glaucoma identified one of these as what they were told. One year after definitive examination, 5 out of 17 (29%) glaucoma patients (all of whom were recommended to have therapy) had failed to return to the Wilmer clinic for 1 year or more. Among glaucoma suspects, 3 out of 7 who were prescribed eye drops did not come back (43%), while 25 out of 37 (68%) of the suspects who were told that therapy was not necessary were lost. This shows a trend toward greater cooperation with follow-up visits when treatment is prescribed and when a more serious diagnosis is given. (P.13, 2 for trend). DISCUSSION IN THE UNITED STATES, HIGHER RATES OF VISUAL IMPAIRment and blindness are associated with lower socioeconomic status, minority ethnic status, and older age. 7 9 While genetic makeup may explain some differences in disease prevalence, 10,11 the higher rates of eye disease among economically disadvantaged persons may be related to barriers to eye care access. Black Americans have lower rates of eye care visits and surgery for glaucoma than would be estimated from the age-specific prevalence of the condition compared with whites The barriers to the provision of treatment could be structural issues in the health care system and/or a result of the behavior and 390 AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2002

6 beliefs of those at risk for eye disease. Our program attempted to assess barriers to care in a community-based screening program with facilitated access to a delivery care system. We recognize that the positive predictive power of a screening examination administered by laypersons is limited. Questionnaire methods have modest success in identifying eye disease, 16 visual acuity testing misses most cases of glaucoma, and screening field tests can be ineffective. Despite these limitations, positive screenees represented a group that was enriched for eye disease relative to the general population of East Baltimore. We tried to maximize the likelihood that a positive screenee would receive care. First, we referred to a local facility at no out-of-pocket cost utilizing a program employee who was a member of the community. The program was well known to be supported by religious community organizations. We offered transportation and scheduled appointments on weekends. Bifocal eyeglasses were available at $40. The rate at which participants accessed care was increased by these efforts compared with typical rates of keeping appointments in the Wilmer General Eye Service. Yet, fewer than half of those who agreed to schedule a definitive examination ultimately did come for the visit. In their telephone interviews, 75% of respondents stated that before our program the cost of an eye examination had been a barrier to seeking care. Many in our target group have no medical insurance and those with insurance (including Medicare) rarely have coverage for routine eye examination, eyeglasses, or prescription eye medications. Despite the fact that some barriers were minimized, we were unable to induce many positive screenees to schedule a visit and half of those who scheduled did not attend. Defaulters predominately blamed poor memory, failure to receive an appointment, confirmation letter, or personal scheduling conflicts as the reasons that they did not come. However, among those who rescheduled visits after missing the first one, many failed to attend the rescheduled visit after agreeing to come at a specific date, even with a reminder letter. Perhaps, fear of the medical care system or of our health care facility is deeper than is expressed. An important barrier to accessing care is denial of the potential seriousness of an eye problem. Symptoms are minimal in glaucoma, early phases of diabetic retinopathy, and macular degeneration. Participants were more likely to continue to come for visits with a diagnosis of glaucoma compared with glaucoma suspect. This tendency was observed in a similar patient population at our institution. 17 It is conceivable that the more definitive diagnosis and the prescription of medication improved compliance with visits by implying greater seriousness of the disease. However, there was attrition even among persons diagnosed with glaucoma. For example, 4 out of 17 persons found to have glaucoma had previously been diagnosed, but were lost to follow up at the time of screening. One investigation showed that 23% of those receiving initial glaucoma medication in the New Jersey medical assistance program did not fill a second prescription. 18 Those started on more than one medical agent were more often compliant, supporting the concept that cooperation increases when the person perceives the problem as more serious. The same research group found that managed care patients were more compliant with glaucoma eye-drop refilling when they had more frequent visits to the ophthalmologist. 19 Frequent physician contact may confirm for the patient that the disease is severe enough to merit higher compliance. Both of these studies were carried out in settings in which cost was a minimal barrier to cooperation with treatment (medical assistance patients and health maintenance organization patients). The experience of the community-based Hoffberger program demonstrates that a substantial effort is required to seek out persons who are at the greatest risk for eye disease and who are least likely to be part of the health care system. Those who are more needy are more difficult to access, particularly senior citizens with multiple disabilities and those without family support. The easiest sites at which to screen (for example, health fairs) are not the best ones in which to locate the underserved. The homeless are the most difficult to help, as they rarely have transportation to a future examination and cannot be contacted at a fixed site or by telephone. We found that it was important to identify social service agencies that have frequent contact with senior citizens. We mapped census tracts using available data to identify areas with higher concentrations of the poor and older citizens. We used radio broadcasts to announce screening programs on stations that have a demographic distribution of listeners that matches those with higher risk of eye disease. We trained screeners at fixed sites that can access the high-risk participant on a recurring basis. We screened and examined persons during evening and weekend hours. Other programs have had only limited success in increasing patient participation in eye examination. The Health Care Financing Administration mailed letters to known diabetic Medicare recipients that encouraged them to undergo eye examination. This produced no significant sustained increase in visits coded as retinal examinations. 21 An Australian program used a combination of targeted mailings and broadcast and print media announcements to increase those in a sample population who were examined for diabetes. They measured only a modest improvement, as 55% had undergone examination at baseline increasing to 70% after the intervention. 22 In summary, community screening for eye disease in an urban setting identifies many persons with visual impairment and eye diseases meriting management. The relatively low efficiency of this approach should be studied further by examinations of similar programs in other locations. Despite removal of some existing barriers to care, it is difficult to induce some persons to access examination and treatment. Maintenance of continuity in VOL. 133, NO. 3 COMMUNITY SCREENING FOR EYE DISEASE 391

7 care is not optimal and further research into improvements in these areas should be conducted. ACKNOWLEDGMENTS The authors thank Adrian Mosley, Lane Cameron, Laura McKiernan, Ondra Walker, Patrice Tucker, Yvonne Blake, Yana Rachinskaya, Felicia Keel, Eve Higginbotham, MD, Nancy Ellish, PhD, and the other members of the Hoffberger Program staff, Irvin Fuss, OD, the clergy of East Baltimore, the Maryland Society for Sight, and our many volunteers for their hard work and devotion to their community and to this program. REFERENCES 1. Quigley HA. The number of persons with glaucoma worldwide. Br J Ophthalmol 1996;80: Wang F, Javitt JC. Eye care for elderly Americans with diabetes mellitus. Failure to meet current guidelines. Ophthalmology 1996;103: Mukamel DB, Bresnick GH, Wang Q, Dickey CF. Barriers to compliance with screening guidelines for diabetic retinopathy. Ophthalmic Epidemiol 1999;6: Sponsel WE, Ritch R, Stamper R, Higginbotham EJ, Anderson DR, Wilson MR, Zimmerman TJ. Prevent Blindness America visual field screening study. The Prevent Blindness America Glaucoma Advisory Committee. Am J Ophthalmol 1995;120: Damato BE Chyla J, McClure E, Jay JL, Allan D. A hand held OKP chart for screening of glaucoma. Eye 1990;4: Quigley HA. Identification of glaucomatous visual field abnormality with the screening protocol of frequency doubling technology. Am J Ophthalmol 1998;125: Tielsch JM, Sommer A, Witt K, Katz J, Royall RM, The Baltimore Eye Survey Research Group. Blindness and visual impairment in an American urban population: the Baltimore Eye Survey. Arch Ophthalmol 1990;108: Rahmani B, Tielsch JM, Katz J, Gottsch J, Quigley H, Javitt J, Sommer A. The cause-specific prevalence of visual impairment in an urban population. The Baltimore Eye Survey. Ophthalmology 1996;103: Munoz B, West SK, Rubin GS, Schein OD, Quigley HA, Bressler SB, Bandeen-Roche K, SEE study team. Causes of blindness and visual impairment in a population of older Americans: the SEE study. Arch Ophthalmol 2000;118: Tielsch JM, Sommer A, Katz J, Royall RM, Quigley HA, Javitt J. Racial variations in the prevalence of primary open angle glaucoma: the Baltimore Eye Survey. JAMA 1991;266: Buhrmann RR, Quigley HA, Barron Y, West SK, Oliva MS, Mmbaga BBO. The prevalence of glaucoma in a rural east African population. Invest Ophthalmol Vis Sci 2000;41: Javitt JC, McBean AM, Nicholson GA, Babish JD, Warren JL, Krakauer H. Undertreatment of glaucoma among black Americans. N Engl J Med 1991;325: Chiang YP, Wang F, Javitt JC. Office visits to ophthalmologists and other physicians for eye care among the U.S. population, Public Health Rep 1995;110: Wang F. Javitt JC, Tielsch JM. Racial variations in treatment for glaucoma and cataract among Medicare recipients. Ophthalmic Epidemiol 1997;4: Devgan U, Yu F, Kim E, Coleman A. Surgical undertreatment of glaucoma in black beneficiaries of Medicare. Arch Ophthalmol 2000;118: Strahlman E, Ford D, Whelton P, Sommer A. Vision screening in a primary care setting. A missed opportunity? Arch Intern Med 1990;150: Kosoko O, Quigley HA, Vitale S, Enger C, Kerrigan LA, Tielsch JM. Risk factors for non-compliance with glaucoma follow-up visits. Ophthalmology 1998;105: Gurwitz JH, Glynn RJ, Monane M, Everitt DE, Gilden D, Smith N, Avorn J. Treatment for glaucoma: adherence by the elderly. Am J Public Health 1993;83: Gurwitz JH, Yeomans SM, Glynn RJ, Lewis BE, Levin R, Avorn J. Patient noncompliance in the managed care setting. The case of medical therapy for glaucoma. Med Care 1998;36: Prela CM, Smilie JG, McInerney MJ, Harwell TS, Helgerson SD. Direct mail intervention to increase retinal examination rates in Medicare beneficiaries with diabetes. Am J Med Qual 2000;15: Lee SJ, McCarty CA, Sicari C, Livingston PM, Harper CA, Taylor HR, Keeffe JE. Recruitment methods for communitybased screening for diabetic retinopathy. Ophthalmic Epidemiol 2000;7: AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2002