8 9 , ‡ 40 years, G 64. Controlling 9 for REE frequency 7or 23 G and costs associated with Y or eye disorder prevalence, 20 Y 9 17,21 65 years and 20 to 8,18 G However, the ideal REE frequency in 17 § vary with age. 6 , Barbara E. Robinson*, Patricia K. Hrynchak ‡ Existing professional guidelines PUBLIC ACCESS (Table 1) are based on expert opinion , Vol. 93, No. 7, July 2016 asymptomatic patients is unknown. Recommendationsage should dependent be as visual outcomes vision deficits optometry. This difference couldommendations arise being from based rec- optometry more may on also disease considerfractive error. detection non-disease Generally, it conditions whereas is such recommended that childrenadults as and have older more re- frequent REEs than youngA and middle conflict age of adults. interest may beexperts perceived for whose guidelines developed profession by benefitsGiven from the a basis highbetween of them, REE and current frequency. the recommendations, potential for the conflict discrepancies of interest, empirical so it is not surprising thatOphthalmology they tends vary by to profession recommend and patient REEs age. less frequently than eye examination frequency. V iagnosis, or a new management. Significant change, assessment 20, and between 1 and 1.5 years for patients Com- G 6,7 reports that 13 , Carolyn M. Machan Susan J. Leat*, and Linda Lillakas † Optometry and Vision Science and Quigley 1.11). FEATURE ARTICLE Y 12 Asymptomatic Patients As well, the economic burden Y there is literature rationalizing 666 Y 5 10 Y 666) 16 1 Y Y 14 Copyright © American Academy of Optometry. Unauthorized reproduction of this article is prohibited. Copyright © American Academy of Optometry. Unauthorized reproduction of this article Value of Routine Eye Examinations in In asymptomatic patients, comprehensive routine optometric eye examinations detect a significant number of American Academy of Optometry The Waterloo Eye Study (WatES) database was created from a retrospective file review of 6397 patients seen at the To determine if routine eye examinations in asymptomatic patients result in spectacle prescription change, new The prevalence of asymptomatic has been Of 2656 asymptomatic patients, 1078 (41%) patients had spectacle prescription changes, 434 (16%) patients had of vision loss has been shown to be significant. ood vision and eye healthperson’s are quality essential of life. components to a 2016 1.037). Similarly, controlling for age and sex, increased assessment interval was associated with having a significant 8,9 * Y

BA OD MSc

For symptomatic patients, few would argue against the need for School of Optometry and Vision Science, University of Waterloo, Waterloo, † ‡ § *PhD Elizabeth L. Irving*, Joel D. Harris Key Words: routine eye examinations, asymptomatic patients, age, diagnostic value, public health new eye conditions and/or result in management(Optom changes. Vis The number Sci detected 2016;93:660 increases with age and assessment interval. change (OR = 1.06,Conclusions. 95% CI 1.02 for assessment interval1.029 and sex, increasing age was associated with having a significant change (OR = 1.03, 95% CI prehensive routine eye examinations (REE)preventative are role believed in to vision play lossdisease. a by screening for asymptomatic eye an eye examination. Similarly, for patients considered at high risk for ocular disorders, e.g. diabetics, less than 50% of patients with know they have it. respectively, approximately 1.5 years for patients 7 to found to be 14 to 26% of patients

Ontario, Canada (all authors). G new critical diagnoses, 809(significant change). (31%) Median assessment patients intervals were had 2.9 and new 2.8 managements, years for and age groups 1535 40 to (58%) patients had at least one of these interval, and age were extractedfrequency from the of database patients for with all significantResults. asymptomatic change patients and presenting the for a median routine assessment eye interval examination. were The determined for different age groups. Methods. University of Waterloo Optometry Clinic. Significant changesa since change the in previous spectacle assessment prescription, presence (significant of change) a were new defined critical d as ABSTRACT Purpose. critical diagnosis, orsessments new (assessment management interval) of impact existing detection rates. conditions. We also investigate whether age and time between as- 1040-5488/16/9307-0660/0 VOL. 93, NO.OPTOMETRY 7, AND PP. VISION 660 SCIENCE Copyright

Downloaded from https://journals.lww.com/optvissci by BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD31kf1ZzWr4Xvi6JM0b2HZz1kQuZVWbPr1Y8oDrC8qUk0Vqre8pXLdhA== on 05/12/2020 Downloaded from https://journals.lww.com/optvissci by BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD31kf1ZzWr4Xvi6JM0b2HZz1kQuZVWbPr1Y8oDrC8qUk0Vqre8pXLdhA== on 05/12/2020 Routine Eye Examinations_ Value in Asymptomatic PatientsVIrving et al. 661 TABLE 1. Summary of guidelines for the frequency of routine eye examinations (REE) from different North American professional bodies: the recommended time between assessments (assessment interval) is in years unless otherwise indicated

American Academy of American Optometric Canadian Association of Canadian Ophthalmological Age Groups (yr) Ophthalmology (AAO)17 Association (AOA)21 Optometrists (CAO)22 Society (COS)23 G2 Newborn 1 exam @ 6 mo 1 exam @ 6Y9mo 2Y5 1 exam @ 3 yr 1 exam @ 3 yr 1 exam @ 2Y5yr 6Y17 1Y22 1 18Y19 Not recommended 2 1 20Y39 Not recommended 2 2Y310 40Y49 2Y42 2 5 50Y54 2Y42 2 5 55Y59 1Y32 2 3 60Y64 1Y31 2 3 Q65 1Y21 1 2 evidence on how REE frequency influences eye disorder detection vision, or flashes and ), are referred to hereafter as asymp- is needed. tomatic REE patients. There were some patients who initially Some research is available to support annual REEs in patients presented for a REE but reported symptoms when specifically 965 years.8,11,18 Older adults having frequent REEs are less likely questioned. These patients were excluded from the main analysis, to experience vision loss.9,24 For individuals G65 years, the related but their overall percentage of significant change is reported for literature is more sparse. Werner25 reviewed the files of 25- to 35-year- comparison. old optometric patients and found Q38% had refractive changes, 4% A spectacle prescription change was considered to be significant had undiagnosed disease, and 15.8% had disorders, if in at least one eye, the sphere, cylinder, or any reading addition when examined within 2 years. Assessment intervals of 2 to 5 years changed by 90.5D from the entering to the exiting spectacle resulted in higher numbers of significant findings (newly diagnosed prescription, or if the cylinder axis changed as follows: 915 degrees disease, Q0.50D change in , failure to meet Sheard’s if the absolute value of the final cylinder value was G1D, 910 Criterion for vergence disorders, and decreased amplitude of ac- degrees if the cylinder was Q1D but G2D, or 95 degrees if the commodation for age). A recent study found that a previous-year eye cylinder was Q2D.30 A critical diagnosis was considered new if it examination was associated with better vision status in 40- to 65-year- was not reported in the clinic file case history or at previous ex- old patients.26 Fraser et al.27 found a 25% increased odds of pa- aminations. For patients whose most recent previous assessment tients (940 years) first presenting with advanced glaucomatous visual was not performed at the University of Waterloo (n = 742), di- field loss for each year since the last visit to an optometrist. In patients agnoses were considered to be new if they were not recorded in the 940 years of age, with normal baseline results, Taylor et al.28 reported case history. New diagnoses were classified as critical if the dis- that over a 5-year period, 2.39% had a loss in visual acuity to poorer order or abnormal finding resulted in vision loss, could progress to than 20/40. Thirty-seven percent of those patients did not notice a vision loss or physical discomfort, or had a systemic implication change in vision. (see Table 2). A management (not including prescription change) The present study is interested in determining the percentage of was considered new if it was not initiated at a previous visit or if asymptomatic patients for which REEs result in spectacle pre- there was a change compared to the last available information. scription change, new critical diagnosis, or new management of New managements included referrals, new treatment, or changes existing conditions for six age groups. We also report the median in monitoring schedule. time intervals between REEs for patients in the different age The numbers of asymptomatic REE patients with significant groups and compare them to currently recommended guidelines. change (defined as one or more of a spectacle prescription change, new critical diagnosis, or new management) since their last assess- ment were determined for each of the following age groups: G4years, METHODS 4toG7years,7toG20 years, 20 to G40 years, 40 to G65 years, and The Waterloo Eye Study (WatES) is a retrospective cross-sectional Q65 years. The time between assessments (assessment interval) was database of patients who presented at the University of Waterloo determined from the number of years between the study assessment Optometry Clinic during a 1-year period from January 2007 to and the patient’s previous eye examination. Assessment intervals were January 2008. The methods and repeatability of WatES data ab- calculated for all patients whose last eye examination was Q1year straction and population representation have been outlined earlier.29 before the study assessment. The median assessment interval was The study was approved by the Office of Research Ethics at the calculated for each age group. The numbers of patients with a spectacle University of Waterloo. Data were extracted for all patients whose prescription change, new critical diagnosis, new management, or any reason for presenting was to have a routine eye examination as of these (significant change) were determined for patients presenting reported in the case history (including those presenting for em- for a first ever assessment as well as for the following assessment in- ployment purposes, to obtain contact lenses, or to replace specta- tervals: 1 to G2, 2 to G3, 3 to G5, 5 to G10, and 10+ years since their cles). Those who did not report any eye-related symptoms, even previous assessment. Odds ratios (OR) were calculated for patient during case history questioning (e.g. headaches, , blurred age, patient sex, assessment interval, and significant change using

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Copyright © American Academy of Optometry. Unauthorized reproduction of this article is prohibited. 662 Routine Eye Examinations_ Value in Asymptomatic PatientsVIrving et al. TABLE 2. Ocular disorders and abnormal findings that were considered to be a critical diagnosis

Ocular Motor or Binocular Vision Disorders Posterior Segment Anterior Segment or Adnexa & & & Anterior or iritis & Browns syndrome & Choroidal melanoma & with associated decrease in visual acuity & Decompensating phoria & Coloboma & Cellulitis (orbital or periorbital) & & Diabetic & Corneal scarring with functional loss & Paresis of an extra-ocular muscle & Disc hemorrhage & Epithelial basement membrane disease & & (s) & & Glaucoma & Infectious & Hollenhorst plaque & coloboma & Lattice degeneration & Pigment dispersion syndrome & & & Macular drusen & Narrow angles & & Progressive corneal dystrophies & Optic atrophy & Pseudoexfoliation & & Pseudophakia & & & & Relative afferent pupillary defect & Posterior uveitis & Retinal hypertensive changes & & Retinal hemorrhage(s) & Retinal hole(s) & Retinal solar burn & Retinal vein occlusion & & Vitreoretinal traction & Vitreoretinal tuft A critical ocular diagnosis was one that causes vision loss, either in the past (so there is a need to protect the remaining vision) or has the potential for progression, or has systemic implications. multivariable logistic regression in SPSS. For this analysis, patient when questioned. Thus, there were 2656 asymptomatic REE patients ages and assessment intervals were modeled as continuous variables. (42% of all patients), and this group is the focus of the study. This group had a median age of 38.5 years, an age range from 0.4 to 93.9 years, with 48% males; comparable to the entire WatES clinic population.29 RESULTS Overall, there were 1078 (41%) asymptomatic REE patients with a The WatES database contains 6397 patients, 3913 (61%) of which spectacle prescription change, 434 (16%) with a new critical diagnosis, presented for a REE. Of these, 1257 patients reported symptoms and 809 (31%) with a new management. In total, 1535 (58%)

FIGURE 1. Asymptomatic patients presenting for a routine eye examination (N = 2656) that had a significant change (defined as one or more of a spectacle pre- scription change, new critical diagnosis, or new management) shown as a percentage of patients within each age group for six different age groups. Percentage values are noted above each bar in the graph. The number of asymptomatic patients in each age group was 9500, except those G4years(n=141)and those 4 to G7years(n=150).

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Copyright © American Academy of Optometry. Unauthorized reproduction of this article is prohibited. Routine Eye Examinations_ Value in Asymptomatic PatientsVIrving et al. 663 patients had one or more of these outcomes. As age increased, so Figure 3 shows the effects of age and assessment interval on the did the likelihood of a patient having a significant change (Fig. 1). prevalence of having a significant change (N = 2345). Breakdown Patients G4 years had the lowest prevalence of significant change by category of change can be found in Table 3. For an assessment (8%), and patients Q65 had the highest (78%). The percentage of interval 1 to G2years,Q38% of patients in age groups Q7hada symptomatic REE patients with a significant change was higher significant change. All previously examined patients 4 to G7yearsof (77%) than that for the asymptomatic REE patients (58%). age had an assessment interval of G5 years, with 86% of this age group Previous assessment dates were available for 2606 (98.1%) of seen at 1 to G2 years from their last assessment; 11% of these had a the asymptomatic REE patients. There were 142 patients having significant change. As necessitated by their age, patients G4yearshad their first ever eye examination. Of these, 93% were G20 years of an assessment interval of G3 years. Approximately 92% of these were age, 69% G7 years, and 46% G4 years. Breakdown by age group seen within 1 to G2 years of their last assessment; close to 5% had a and category of change can be found in Table 3. significant change. Through logistic regression analysis, increasing age The assessment interval was G1 year for 119 patients, and these was found to be significantly associatedwithincreasedoddsofhaving patients along with the first eye examination patients were ex- a significant change (OR = 1.03, 95% CI 1.03Y1.04) while con- cluded from the subsequent analysis. Median assessment interval trolling for assessment interval and sex. For every 1-year increase in values for the remaining 2345 patients, grouped by age, are shown age, there was a 3% increase in the odds of having a significant change. in Figure 2. Median assessment intervals were greatest for patients Similarly, when controlling for age and sex, an increase in assessment in the 20 to G40 and 40 to G65 age groups, at 2.8 and 2.9 years interval was associated with increased likelihood of having a significant between assessments, respectively. The median assessment interval change (OR = 1.06 per year, 95% CI 1.02Y1.11). Patient sex was for patients 7 to G20 years was just over 1.5 years and between 1 not significantly associated with having a significant change (OR = and 1.5 years in patients G7andQ65 years. 1.07 for females, 95% CI 0.90Y1.29).

TABLE 3. The number of asymptomatic study patients (%) with significant changes by category, age group, and assessment interval

0toG4yr 4toG7yr 7toG20 yr 20 to G40 yr 40 to G65 yr Q65 yr Age Group (yr) No. Patients (%) First Assess Spectacle prescription change 1 (2) 4 (12) 9 (26) 3 (43) 2 (100) 1 (100) New critical diagnosis 0 (0) 2 (6) 2 (6) 0 (0) 1 (50) 1 (100) New management 1 (2) 3 (9) 3 (9) 1 (14) 1 (50) 1 (100) Significant change 2 (3) 5 (15) 10 (29) 4 (57) 2 (100) 1 (100) Total Patients with First Assessment (n = 142) 65 33 34 7 2 1 Assessment Intervals (yr) No. Patients (%) 1toG2 Spectacle prescription change 2 (5) 8 (10) 80 (27) 38 (40) 49 (49) 250 (55) New critical diagnosis 0 (0) 1 (1) 9 (3) 10 (10) 13 (13) 128 (28) New management 0 (0) 1 (1) 42 (14) 28 (29) 28 (28) 207 (45) Significant change 2 (5) 9 (11) 114 (38) 56 (58) 67 (66) 351 (77) Total patients 44 80 299 96 101 455 2toG3 Spectacle prescription change 0 (0) 0 (0) 34 (32) 70 (41) 111 (52) 51 (53) New critical diagnosis 0 (0) 0 (0) 3 (3) 16 (9) 48 (22) 34 (35) New management 0 (0) 0 (0) 20 (19) 38 (22) 89 (41) 46 (47) Significant change 0 (0) 0 (0) 48 (46) 95 (56) 157 (73) 75 (77) Total patients 4 10 105 171 215 97 3toG5 Spectacle prescription change 0 (0) 15 (26) 48 (36) 113 (54) 42 (58) New critical diagnosis 0 (0) 4 (7) 18 (13) 43 (20) 35 (49) New management 0 (0) 8 (14) 47 (35) 93 (44) 43 (60) Significant change 0 (0) 19 (33) 86 (64) 162 (77) 58 (81) Total patients 0 3 58 134 210 72 5toG10 Spectacle prescription change 4 (31) 26 (46) 34 (58) 12 (63) New critical diagnosis 1 (8) 4 (7) 16 (27) 10 (53) New management 4 (31) 14 (25) 28 (47) 12 (63) Significant change 7 (54) 34 (61) 45 (76) 17 (89) Total patients 0 0 13 56 59 19 Q10 Spectacle prescription change 0 (0) 3 (15) 7 (41) 2 (33) New critical diagnosis 0 (0) 2 (10) 7 (41) 3 (50) New management 0 (0) 7 (35) 7 (41) 5 (83) Significant change 0 (0) 8 (40) 12 (71) 6 (100) Total patients 0 0 1 20 17 6 Total patients with interval Q1 yr (n = 2345) 48 93 476 477 602 649 Patients with a significant change and interval Q1 yr 2 (4) 9 (10) 188 (39) 279 (58) 443 (74) 507 (78)

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Copyright © American Academy of Optometry. Unauthorized reproduction of this article is prohibited. 664 Routine Eye Examinations_ Value in Asymptomatic PatientsVIrving et al.

FIGURE 2. Median assessment interval per age group, for asymptomatic patients presenting for a routine eye examination for whom the time since their previous eye examination was known (N = 2345). Assessment interval values in years are noted above each bar in the graph.

Figure 4 demonstrates that across all assessment intervals except known age-related ocular changes such as and increasing Q10 years, the most frequent contributor to a significant change prevalence of eye disease.8,18Y20 It also makes sense that as the as- for the 2487 asymptomatic REE patients was a spectacle prescription sessment interval increased, the odds of having a significant change change, followed by a change in management and, lastly, a new critical increased. The longer a patient waits for their next assessment, the diagnosis. The prevalence of any significant change as well as a change older they will be at presentation, increasing the risk of age-related in each category appears to increase with longer assessment intervals conditions. However, we also found an association between assess- (Fig.4,Table3).Exceptionsincludespectacleprescriptionchange ment interval and detection of a significant change when controlling and any significant change at 910 years, and new management for 5 to for age, so although the association between age and assessment in- e10 year interval. At 1 to G2 years, nearly 15% of patients had a new terval does play a role, it is not the sole explanation. Greater assess- critical diagnosis which increased to 27% for an interval Q10 years. ment intervals would allow more time for a disease or condition to Similarly, prevalence of management change ranged from a mini- develop, irrespective of age. mum of 28% between 1 and G2yearstoamaximumof43%at Many factors influence the assessment interval for individual Q10 years. Prescription changes were lowest at 40% for 1 to G2years patients including patient age, cost of examination, insurance and highest at 52% for 5 to G10 years. The frequency of patients coverage, recommendations given by practitioners or professional with any significant change increased from a minimum of 56% be- bodies, practice recalls (not applicable at this clinic), as well as tween 1 and G2 years to a maximum of 70% between 5 and e10 years. patients’ perceived risk of and their under- standing of the consequences of not seeking eye care. The observed median assessment interval for the various asymptomatic REE age DISCUSSION groups (how often patients have an REE, Fig. 2) matches more More than half of the asymptomatic patients (58%) who closely the recommended optometric guidelines21,22 than the age- presented for a REE had a change in ocular status or care compared related trend in significant change outcomes found in the current with 77% of symptomatic REE patients. In asymptomatic patients, study (Fig. 1). Presumably, this is because this is how they are age was a strong predictor of having a significant change. This was instructed by practitioners. REEs for patients aged 20 to 64 years true regardless of the assessment interval and corresponds well with were not publicly funded except for 8 defined medical conditions.

FIGURE 3. Asymptomatic patients presenting for a routine eye examination (N = 2345) that had a significant change (defined as one or more of a spectacle prescription change, new critical diagnosis, or new management) from their previous assessment, shown as a percentage of patients within each age group for six age groups and five assessment intervals.

Optometry and Vision Science, Vol. 93, No. 7, July 2016

Copyright © American Academy of Optometry. Unauthorized reproduction of this article is prohibited. Routine Eye Examinations_ Value in Asymptomatic PatientsVIrving et al. 665

FIGURE 4. Asymptomatic patients presenting for a routine eye examination (N = 2487) with a spectacle prescription change, new critical diagnosis, new management, or any significant change (defined as one or more of a spectacle prescription change, new critical diagnosis, or new management) shown as a percentage of patients within assessment interval for each of six assessment intervals.

Annual REEs for patients G20 and 964 years were publically likely to have a critical diagnosis of which they were unaware than funded. Jin et al.31 showed that de-insurance of eye examinations those Q65 years. reduced the uptake of eye examinations for people in lower income In the WatES clinic population, the detection of significant levels. The WatES clinic is in an area of slightly above average socio- change for patients Q7 years of age is 938% for an assessment interval economic status compared to the province of Ontario overall.32 of 1 to G2 years (Fig. 3). This is substantial and although we have not Patients in funded age groups had smaller time intervals between done an economic analysis, it could be argued that patients 97years assessments than non-funded age groups (Fig. 2), suggesting that should have an eye examination every year. In asymptomatic REE those with above average socio-economic status may also be affected patients G7 years of age, the detection of significant change was by a lack of insurance or public funding. Furthermore, based on data much lower. Given the potential inability of young children to from the Canadian Longitudinal National Population Health communicate symptoms and the impact of disorders on visual Survey, Chan et al.33 found that for patients 65 years or older, provinces development (e.g. amblyopia34), policy makers may wish to choose a where REEs were not funded had reduced patient awareness of lower threshold of detection for this age group when determining glaucoma and cataracts, and increased vision loss. recommended eye examination frequency. Comparing our data to the existing literature is difficult because Limitations of the current study include those inherent in a cross- the age ranges, study populations, conditions evaluated, criteria sectional study design. Although a clinical population may not for change, exclusion criteria, and dates of studies (which may represent the general population, it is representative of those who are reflect scope of practice changes) all vary.12,25,27 Fraser27 studied actually seeking care. The WatES clinic population does compare patients with newly diagnosed glaucoma and found the adjusted favorably in terms of patient age and sex distribution to a nationwide odds ratio of first presenting with advanced glaucoma increased by survey of Canadian optometric practices.11,29 Robinson11 found 1.25 times per year since their last visit to an optometrist. Al- that 32.6% of patients that presented to optometric practices came though Werner’s25 data were derived from an academic optometric for a REE and expressed no concerns compared with 41% of the population, the data covered a more limited age range, potentially a WatES clinic patient population classified as asymptomatic REE different patient demographic, had different exclusion criteria, and patients. Both of these values contradict Michaud and Forcier’s10 was conducted 25 years earlier than WatES. The closest comparison claim that asymptomatic patients are rarely seen in an optometry is our 20 to G40 years age group and 1 to G2 years assessment interval clinic. It is possible that some patient symptoms and/or findings to their 25- to 35-year-old patients and G24 months assessment were not recorded despite routine questioning of every patient. interval. Their finding of 15% of asymptomatic patients having Missed examination findings would result in conservative estimates refractive, disease, or binocular vision problems is considerably lower whereas missed symptoms would overestimate significant changes if than our 58% of asymptomatic patients with a significant change. persons who were not truly asymptomatic were inadvertently included. Wang et al.12 studied patients who were Q40 years of age from a In general, assessment intervals for the various asymptomatic primary care clinic in a teaching hospital. Their population was REE patient age groups closely match the Canadian Optometric predominately African American, had a high prevalence of chronic guidelines. Given an overall 950% detection of significant change, diseases, and had low socioeconomic status. They found a pre- routine eye examinations do appear to be productive in asymp- valence of unknown eye disease of 43% for a 1 to G2yearas- tomatic patients, and this appears to increase with age. sessment interval. WatES new critical diagnosis values for the only comparable assessment interval were lower, 13 and 28% for ACKNOWLEDGMENTS 40 to G65 and Q65 years, respectively. Similar to Wang et al.12,we G None of the authors have any financial interests or relationships to disclose. found an increase in new critical diagnoses for patients 40 to 65 This work was supported by Canada Research Chair #950-202761 and VSP and Q65 years when the assessment interval increased. In contrast Vision Care for Life. to Wang et al.12, we did not find that persons 40 to G65 were more Received July 31, 2015; accepted December 30, 2015.

Optometry and Vision Science, Vol. 93, No. 7, July 2016

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Optometry and Vision Science, Vol. 93, No. 7, July 2016

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