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BioMed Central Page 1 of 6 (page number not for citation purposes) BMC Family Practice BMC Family Practice 2002, 3 x Research article Can Australian general practitioners effectively screen for diabetic retinopathy? A pilot study Claire L Jackson* 1 , Laurence Hirst 2 , Inge C de Jong 1 and Nadine Smith 3 Address: 1 Mater University of Queensland Centre for General Practice and Primary Health Care Integration, South Brisbane, Queensland 4101, Australia, 2 University of Queensland Professorial Eye Unit, Princess Alexandra Hospital, Woolloongabba, Queensland, Australia and 3 University of Queensland School of Population Health, Faculty of Health Sciences, Herston Rd, Herston, 4006, Australia E-mail: Claire L Jackson* - [email protected]; Laurence Hirst - [email protected]; Inge C de Jong - [email protected]; Nadine Smith - [email protected] *Corresponding author Abstract Background: Diabetes has been identified as one of the national health priority areas in Australia. After 20 years of diabetes most patients can be expected to develop diabetic retinopathy which, if undetected, is likely to cause significant visual loss or blindness. This paper reports on a pilot study aimed to test the ability of Australian GPs to clinically recognise diabetic retinopathy following a brief training intervention. Method: 17 GPs from a Brisbane Division of General Practice were recruited to participate in a clinical upskilling intervention pilot. Participant scores on clinical assessments were used to analyse GP sensitivity and specificity in screening for diabetic retinopathy. Results were compared with the NHMRC guidelines for acceptable screening accuracy. Results: Ten of the 17 GPs (59%) achieved a screening sensitivity of 25% or less in the pre test, three (18%) a sensitivity of 50%, and four (23%) achieved a sensitivity of 75%. In the post-test, all seventeen GPs achieved between 50 and 100% sensitivity. In the pre-test, thirteen (76%) GPs achieved a screening specificity of less than or equal to 50%, and four (23%) a specificity of 75 %. In the post test, four GPs (23%) rated a screening specificity of less than 50%, six (35%) achieved a specificity of 66%, and seven (41%) 100% specificity. Conclusion: 24% of GPs met the NHMRC diabetic retinopathy screening criterion prior to the workshop, and 94% following this brief training intervention. Australian GPs are capable of a much more significant role in community screening for diabetic retinopathy. Background Diabetes mellitus constitutes a major Australian public health problem. It has been identified as one of our na- tional health priority areas[1], and recent data suggests that up to 7.5% of the Australian adult population now suffers from this condition. After 20 years of diabetes most patients can be expected to develop diabetic retinopa- thy[3] which, if undetected, is likely to cause significant visual loss or blindness. A recent Australian survey record- ed almost 1/3 of patients with self-reported diabetes hav- ing diabetic retinopathy.[4] However, if detected early by appropriate retinal examination, followed and treated by Published: 7 March 2002 BMC Family Practice 2002, 3:4 Received: 19 November 2001 Accepted: 7 March 2002 This article is available from: http://www.biomedcentral.com/1471-2296/3/4 © 2002 Jackson et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any purpose, provided this notice is preserved along with the article's original URL.

Can Australian general practitioners effectively screen for diabetic retinopathy? A pilot study

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BioMed CentralBMC Family Practice

BMC Family Practice 2002, 3 xResearch articleCan Australian general practitioners effectively screen for diabetic retinopathy? A pilot studyClaire L Jackson*1, Laurence Hirst2, Inge C de Jong1 and Nadine Smith3

Address: 1Mater University of Queensland Centre for General Practice and Primary Health Care Integration, South Brisbane, Queensland 4101, Australia, 2University of Queensland Professorial Eye Unit, Princess Alexandra Hospital, Woolloongabba, Queensland, Australia and 3University of Queensland School of Population Health, Faculty of Health Sciences, Herston Rd, Herston, 4006, Australia

E-mail: Claire L Jackson* - [email protected]; Laurence Hirst - [email protected]; Inge C de Jong - [email protected]; Nadine Smith - [email protected]

*Corresponding author

AbstractBackground: Diabetes has been identified as one of the national health priority areas in Australia.After 20 years of diabetes most patients can be expected to develop diabetic retinopathy which, ifundetected, is likely to cause significant visual loss or blindness. This paper reports on a pilot studyaimed to test the ability of Australian GPs to clinically recognise diabetic retinopathy following abrief training intervention.

Method: 17 GPs from a Brisbane Division of General Practice were recruited to participate in aclinical upskilling intervention pilot. Participant scores on clinical assessments were used to analyseGP sensitivity and specificity in screening for diabetic retinopathy. Results were compared with theNHMRC guidelines for acceptable screening accuracy.

Results: Ten of the 17 GPs (59%) achieved a screening sensitivity of 25% or less in the pre test,three (18%) a sensitivity of 50%, and four (23%) achieved a sensitivity of ≥ 75%. In the post-test, allseventeen GPs achieved between 50 and 100% sensitivity. In the pre-test, thirteen (76%) GPsachieved a screening specificity of less than or equal to 50%, and four (23%) a specificity of 75 %. Inthe post test, four GPs (23%) rated a screening specificity of less than 50%, six (35%) achieved aspecificity of 66%, and seven (41%) 100% specificity.

Conclusion: 24% of GPs met the NHMRC diabetic retinopathy screening criterion prior to theworkshop, and 94% following this brief training intervention. Australian GPs are capable of a muchmore significant role in community screening for diabetic retinopathy.

BackgroundDiabetes mellitus constitutes a major Australian publichealth problem. It has been identified as one of our na-tional health priority areas[1], and recent data suggeststhat up to 7.5% of the Australian adult population nowsuffers from this condition. After 20 years of diabetes most

patients can be expected to develop diabetic retinopa-thy[3] which, if undetected, is likely to cause significantvisual loss or blindness. A recent Australian survey record-ed almost 1/3 of patients with self-reported diabetes hav-ing diabetic retinopathy.[4] However, if detected early byappropriate retinal examination, followed and treated by

Published: 7 March 2002

BMC Family Practice 2002, 3:4

Received: 19 November 2001Accepted: 7 March 2002

This article is available from: http://www.biomedcentral.com/1471-2296/3/4

© 2002 Jackson et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any purpose, provided this notice is preserved along with the article's original URL.

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laser photocoagulation, most patients can be saved frommajor visual loss. [5–7]

Our National Health and Medical Research Council (NH-MRC) Guidelines on the management of diabetic retinop-athy, recommend regular ocular review to detect, treat andminimize such visual morbidity. [8] Recent Australianstudies, however, have documented only a relatively smallproportion of Australians with diabetes receiving suchsight-saving examinations. The Melbourne Visual Impair-ment Project, a large population-based epidemiologicalstudy of 4,744 Victorians with diabetes, found that onlyhalf the sample surveyed reported a retinal examinationwithin the last 2 years. Worryingly, participants with dia-betic retinopathy were no more likely to have had an ex-amination than those without (52.9% v 49.3% p =0.66)[3]. The National Divisions Diabetes Program, a sur-vey of the treatment of diabetes in 4,359 patients across 7Divisions of General Practice, recorded 49.6% of patientsto have had an appropriate retinal examination over the24 month reporting period. [9]

A number of strategies have been implemented to increasethe number of Australians with diabetes accessing regulareye checks. Remote clinics with annual "fly-in" ophthal-mologists operate in a number of Australian states. Mo-bile retinal cameras, operated by state health departmentsor Divisions of General Practice, have recently improvedcommunity access to screening,[10] but are expensive topurchase and operate. Australian optometrists are offeringtheir services in the area of diabetic retinopathy screening.However, little attention to date has focused around theuse of appropriately-trained general practitioners in offer-ing effective and accessible screening for diabetic retinop-athy. We aimed to determine whether generalpractitioners could be trained to identify the importantfeatures of diabetic retinopathy in a short training timeand with an acceptable degree of sensitivity and specifici-ty.

MethodSeventeen GPs from the Bayside Division of General Prac-tice self-selected to participate in a Divisional Eye Upskill-ing Project, funded by the Department of Health andHuman Services. As part of this program, the University ofQueensland Departments of Ophthalmology and GeneralPractice were asked to design a brief 'hands-on' education-al intervention to assist GP skill development in the ocu-lar assessment and management of diabetes mellitus andprimary open angle glaucoma. The complete program andits evaluation has been documented in a previous paper.[11] Details of the diabetic retinopathy training interven-tion are displayed in Table 1.

All sessions were highly interactive and used patients forskill demonstration wherever possible. These sessionswere conducted within the Professorial Eye Unit, PrincessAlexandra Hospital, using patients with good clinicalsigns. Doctors were urged to practice and refine skills intheir own practices between workshops, and to commenton barriers and supports to the use of the skills in theirclinical practice.

All GPs underwent a comprehensive practical assessmentof their eye skills prior to undertaking the intervention,and completed an identical assessment at the conclusion(pre and post test). The pre and post evaluation relevantto the diabetes retinopathy skills component consisted ofeight (8) two-minute patient fundal examinations con-ducted a month prior and a month following the skillsprogram. Four (4) of the patients involved in this assess-ment suffered from diabetic retinopathy, and four (4) hadnormal fundi.. The gold standard used to determine thepresence or absence of diabetic retinopathy was the agreedclinical assessment by two academic ophthalmologists.All four diabetic (4) patients had background diabeticretinopathy. Every attempt was made to make pre andpost evaluation assessments for the diabetes patients iden-tical. However, one of the four diabetic patients participat-ing in the pre-test, was unable to return for the finalevaluation session. He was replaced, as closely as possible,by a patient with similar fundal appearance. The four pa-

Table 1: Diabetes segment of the GP Eye Upskilling Program

Workshop 1 Workshop 2

1. Overview diabetic eye disease 30 mins 1. Patient fundoscopy clinic 30 mins2. Fundoscopy video 15 mins 2. Question and answer session 15 mins3. Fundoscopy practice 30 mins 3. Use of skills in the general practice time frame 15 mins4. Slide review session 15 mins 4. Slide review 15 mins5. Patient fundoscopy clinic session 35 mins

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tients with normal fundi were recruited from the ward andoutpatient departments on the day of assessment. One"normal" failed to attend the post-test. The post test wasin all other respects conducted identically to the pre test.GPs were not informed of the retinopathy status of the pa-tients used in the pre-evaluation testing and these patientswere separated from clinical teaching sessions during theeducational intervention.

All patients were unknown to participating GPs. The Uni-versity of Queensland ophthalmology staff supervised alltraining sessions and both assessments. Ethical approvalto conduct the study was sought and received from thePrincess Alexandra Hospital Ethics Committee.

Statistical methodParticipant performance on the patient fundal assess-ment, pre and post educational intervention, was used todetermine sensitivity and specificity of screening for dia-betic retinopathy. Sensitivity was calculated as the ratio ofpatient assessments correctly identified by the GPs as dia-betic, to the total number of diabetic retinopathy positivecases (four subjects in total in both pre and post tests).Specificity was calculated as a ratio of the number of nor-mal cases correctly identified over the total number ofnormals participating in both tests (four subjects in thepre-test, and three subjects in the post-test). [12]

For each GP, sensitivity pre and post educational interven-tion was classified 'not satisfactory' if sensitivity was lessthan 60% and classified 'satisfactory' if sensitivity wasequal to or greater than 60%. For each GP, specificity preand post educational intervention was classified 'not sat-isfactory' if specificity was less than 60% and classified'satisfactory' if specificity was equal to or greater than60%. McNemar's Test was then used to determine if therewas an association between Sensitivity Classification andeducational intervention. This test was used because it ac-

counts for the paired nature of the data. That is, the sameGPs were evaluated Pre- and Post-workshop. Statisticalsignificance is quoted at the conventional p < 0.05 level.All hypothesis testing was based on two-tailed hypothe-ses. Due to small sample sizes exact significance levelswere used.

ResultsSensitivityPre and post intervention sensitivity results are displayedas percentages in Table 3. Ten GPs (59%) achieved ascreening sensitivity of 25% or less in the pre test, three(18%) scored 50%, two (11.5%) scored 75%, and two(11.5%) recorded 100% sensitivity. In the post test, allseventeen GPs achieved between 50 and 100% sensitivity(1 GP achieved 50% sensitivity, 11 GPs (65%) achieved75% sensitivity, and 5 GPs (29%) achieved 100% sensitiv-ity).

The McNemar test (Table 4) was statistically significantand there was an association between sensitivity classifica-tion and educational invention (p = 0.001). There was asignificant increase in the number GPs with 'satisfactory'sensitivity from Pre- to Post-workshop.

SpecificitySpecificity results, pre and post intervention, are displayedin Table 5. As one of our "normals" failed to appear in thepost test, the number of subjects used in the post assess-ment dropped from four to three, hence the specificitiesare expressed in increments of 25% for the pre test com-pared with increments of 33% for the post test. In the pretest, nine GPs (54%) recorded a screening specificity ofless than 50%, four (23%) a specificity of 50% and four(23%) a specificity of 75%. In the post test, only four GPs(23%) recorded a specificity of less than 50%, six (35%) aspecificity of 66%, and seven (41%) 100% specificity. NoGP recorded 100% specificity in the pre test, whilst 7(41%) recorded 100% screening specificity following theintervention.

The McNemar test (Table 6) was statistically significantand there was an association between specificity classifica-tion and educational invention (p = 0.001). There was asignificant increase in the number GPs with 'satisfactory'specificity from Pre- to Post-workshop.

The NH&MRC publication "Management of DiabeticRetinopathy: a guide for general practitioners' [8] nomi-nates that a "60% detection rate of early Diabetic Retinop-athy (DR) may be sufficient for a successful screeningcampaign, so long as diabetic patients deemed to not haveDR are screened at least every two years." In this study,24% of GPs met this criterion prior to the workshop, and94% met it following the intervention.

Table 2: Workshop Modules (National RACGP / RACO GP Eye Skills Workshop)

Module 1 Vision Testing And Ophthalmic ScreeningModule 2 Concepts And Assessment For GlaucomaModule 3 The Slit LampModule 4 OpthalmoscopyModule 5 Incision Of ChalazionModule 6 Removal Of Corneal Foreign BodiesModule 7 Suture Repair Of EntropionModule 8 Ocular First AidModule 9 The Six Point Eye ExaminationModule 10 How Will This Change My Practice?Module 11 Patient Assessment Clinic (Optional)

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DiscussionThe early identification of diabetic retinopathy is crucial,as effective therapy is now available for the maintenanceof vision in most patients. However, the absence of a sys-tematic approach to such identification for Australianswith diabetes limits our ability to provide optimal visualoutcomes. The limited number of ophthalmologists avail-able in the community restricts their role to the confirma-tion of diabetic retinopathy, grading, and eventualtreatment. The use of a mobile fundus camera and centralreading of all photos remains a potential method of iden-tification of retinopathy, although as yet this has not beenwidely embraced in any single large community (outsideremote areas).

GP screening is rarely suggested as an effective means ofimproving the early detection of diabetic retinopathy inAustralia, yet it offers a number of clear benefits. Generalpractitioners have almost universal access to Australianadults with diabetes, as GPs provide the bulk of adult di-abetes diagnosis and care. As well as managing glucosecontrol, medication, and lifestyle issues, GPs perform reg-ular checks for peripheral neuropathy, nephropathy andmacro vascular disease. An assessment for retinopathycould easily be included as part of the existing annual di-

abetes assessment (as nominated under the latest RACGP/ DA Guidelines). This would negate the need to purchaseand move expensive machinery, or arrange separate ap-pointment times and assessments, and would be cost-ef-fective for both the patient and community. A generalpractice screening model also offers the potential to op-portunistically "catch" unscreened diabetics presenting tothe general practitioner in a variety of other situations.General practitioners have a pre-established referral linkwith local ophthalmologists if early diabetic retinopathyis suspected. In most Australian states, this relationshiphas increasingly included an educational element via theRACGP / RACO National GP Eye Skills Program.

A GP screening model thus has the potential to provide awidely-available, holistic and extremely cost effectivescreening service on a population basis – providing gener-al practitioner skills are adequate for the identificationprocess.

Previous work with general practitioners in this area sug-gested to us that GP reluctance to undertake retinal screen-ing was due to concerns about the time taken for theexamination; a long-standing and unfounded fear of theconsequences of pupillary dilatation; and a lack of confi-dence in undertaking funduscopy with a direct ophthal-moscope. McCarty et al (13) identify lack of dilating dropsin the practice, lack of confidence in detecting changes,concern re time taken and the fear of precipitation of an-gle-closure glaucoma as major barriers to GPs performingdilated ophthalmoscopy with their patients. Strategies toaddress all of these issues and perceptions were addressedas part of the "_How will this change my practice?" mod-ule in our educational intervention (Table 2). Follow upof a separate group of GPs taking this intervention as partof the national RACGP / RACO GP Eye Skills Workshophas demonstrated a sustained change in reported practicein this area [14].

We piloted a brief interactive training intervention to ad-dress these issues. Our GP intervention group reviewedand accepted recent data on the rarity of acute glaucomafollowing pupillary dilitation with short-acting mydriat-ics, and rapidly acquired effective skills in dilated diabeticfundal assessment. A focus of the training was the applica-tion of skills in each individual practitioner's work envi-ronment, and the practicing of skills between sessions inthe general practice setting. This pilot aimed to assess theefficacy of this teaching program in raising the skills ofthose involved to the level of the current NHMRC guide-lines for diabetic retinopathy screening. However, untilpatients are screened more regularly, the detection rate fordiabetic retinopathy may need concomitantly to be higherthan the 60% nominated in this guideline.

Table 3: Sensitivity of GP screening for Diabetic Retinopathy (n = 17)

Pre-workshop Post-workshopSensitivity (%) GPs (n) GPs (n)

0 4 025 6 050 3 175 2 11100 2 5

Table 4: Specificity of GP screening for Diabetic Retinopathy (n = 17)

Pre-workshop Post-workshopSpecificity (%) GPs (n) Specificity (%) GPs (n)

0 3 0 125 650 4 33.3 375 4 66.6 6100 0 100 7

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Following training, 94 % of the general practice studygroup reached this level within a two minute patient ex-amination (both eyes). In addition, the specificity of theidentification was such that it would not provide a grossreferral overload to ophthalmologists for more accurateassessment and treatment. The time and effort requiredcould be easily integrated into an annual review for pa-tients with diabetes. The Royal Australian Colleges ofGeneral Practice and Ophthalmology have implementedthis workshop across Queensland in 2000.

With appropriate training, motivation and support, GPscan make a major contribution in the area of effectivescreening for diabetic retinopathy. Clinicians, educators,bureaucrats and economists within our health systemshould be aware of this in framing future strategies in thearea of diabetes.

Competing interestsNone declared

AcknowledgementsThe authors would like to thank the project manager Manjula Reedy, and the Bayside GPs for their contributions.

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partment of Health and Aged Care: National Health Priority Ar-eas 1999 [http://www.health.gov.au/hsdd/nhpq/3rdnhpa.htm]

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Table 5: Sensitivity Classification of GP screening for Diabetic Retinopathy by Pre-and Post-workshop

Pre-workshop Totalnot satisfactory satisfactory

Post-workshop not satisfactory 1 0 1satisfactory 11 5 16

Total 12 5 17

Table 6: Specificity Classification of GP screening for Diabetic Retinopathy by Pre-and Post-workshop

Pre-workshop Totalnot satisfactory satisfactory

Post-workshop not satisfactory 3 1 4satisfactory 10 3 13

Total 13 4 17

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11. Jackson C, Hirst L, Ambler J, Battistutta D: GPs and eye skills – theheralding of a brave new world? Australian Family Physician 1997,26:409-415

12. Hennekens CH, Burning JE: Epidemiology in medicine: Boston: Lit-tle Brown and Company; 1987

13. McCarty , et al: Managemnt of diabetic retinopathy by generalpractitioners in Victoria" Clin Exper Ophthalmol 1987, 29:12-16

14. Jackson CL, de Jong I, Schlutter P: Changing Clinical Practice: theRACGP/RACO National GP Eye Skills Workshop AustralianFamily Physician 2001, 31:285-91

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