Dermatology: Practical and Conceptual Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 1 Evaluation of the Knowledge of Primary Care Physicians About Important Nail Diseases Before and After a Short Online Training Pauline Greco1,2, Félix Pham1,2, Gérard Duru2, Xavier Lainé2, Stéphane Dalle1,2,3, Luc Thomas1,2,3 1 Dermatology department, Hôpital Lyon Sud, Hospices Civils de Lyon, Lyons, France 2 Claude Bernard Lyon-1 University, Lyon, France 3 Cancer Research Center of Lyon, Lyons, France Key words: nail, primary care physician, education, general practitioner, melanoma Citation: Greco P, Pham F, Duru G, Lainé X, Dalle S, Thomas L. Evaluation of the Knowledge of Primary Care Physicians About Important Nail Diseases Before and After a Short Online Training. Dermatol Pract Concept. 2023;13(3):e2023170. DOI: https://doi.org/10.5826 /dpc.1303a170 Accepted: February 1, 2023; Published: July 2023 Copyright: ©2023 Greco et al. This is an open-access article distributed under the terms of the Creative Commons Attribution- NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: This work was supported in part by grants from Lyon 1 Claude Bernard University (to LT), The Hospices civils de Lyon (to LT) and the Association Vaincre le mélanome (to LT) Competing Interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding Author: Luc Thomas, MD, PhD, Service de dermatologie, Hôpital Lyon Sud, 165 Chemin du Grand Revoyet, 69310 Pierre-Bénite, France. Fax number: +33478865706 Email: luc.thomas@chu-lyon.fr IRB Approval Status: Reviewed and approved by the institutional ethical committee of Lyons (N°20-63) Introduction: Nail diseases are often diagnosed late with a potential prognostic and functional im- pact. This could be partly due to knowledge gaps among primary care physicians (PCPs). Objectives: To evaluate the knowledge about diagnosis and management of ten common/important nail conditions in a population of French PCPs and its improvement after a 31-minute online training session. Methods: We submitted 10 pre-test and post-test clinical cases and an educative online course on the diagnosis and the management of nail diseases to 138 volunteer PCPs; 73 completed the whole training path. Results: Compared to pre-test, more PCPs in the post-test required an urgent second opinion to der- matologist for pigmented melanoma (100% versus 80.3%; P <0.05) and use of inappropriate/danger- ous systemic treatment for trauma-induced nail changes was reduced after the training program (0% versus 6.8%; P <0.05). A lack of knowledge remained after training for amelanotic melanoma with an increase of mycological/bacteriological tests (9.6% versus 0%; P <0.05). Conclusions: Management of nail diseases by our panel of PCPs was suboptimal and was improved after a short online training. ABSTRACT 2 Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 Introduction Nail disorders are very common but might not be very well-known by primary care physicians (PCPs). Although 50% of nail conditions are due to fungal infection, other dis- eases affecting the nail unit are neoplastic, inflammatory, con- genital, traumatic, or related to a systemic disease. Because some of these non-fungal conditions clinically look alike on- ychomycoses, their diagnosis is often missed. Patients may be then exposed to diagnostic delays with important prognostic significance especially in malignant tumors such as subungual melanoma (SUM) or subungual squamous cell carcinoma (SSCC) [1]. Moreover, they are often submitted to inappro- priate treatments. Many publications underline that diagnosis of SUM can be delayed from 9 months to 2.2 years after oc- currence of the first symptoms [2,3]. These diagnostic delays are responsible in part of the apparent worse prognosis of SUM yet, for an equivalent Breslow index, their prognosis is not different from that observed in melanoma occurring else- where on skin [4]. Confounding various nail conditions with fungal infection also led to an inappropriate use of medical resources such as urgent dermatology consultations, imaging, mycology tests and to unnecessary use of antifungal drugs. This is particularly true with repetitive trauma-induced toe- nail changes due to the conflict between the shoe and the tip- toes. This condition not only looks like fungal infection but is also frequently contaminated with fungus, therefore identi- fiable by laboratory tests [5]. In such cases, antifungal treat- ment may show some improvement that is rarely complete and often followed by a relapse since the real cause of the nail change is underestimated. Moreover, subungual glomus-cell tumor (SGCT), a sometimes very painful benign tumor, is known to be frequently left untreated for as long as 1 to 9 years with significant risk of disability and depression [6,7]. Objectives The main objectives of our study were to evaluate the potential lack of knowledge of PCPs about common or prognostically/functionally important nail diseases, to pro- pose an online teaching session and to evaluate its improve- ment, particularly under the perspective of a better use of medical and therapeutic resources. Our secondary goal was to evaluate pieces of knowledge where the improvements were the most significant and to identify topics in which our teaching program could be improved. Methods Study Design We conducted a blinded anonymous study on 138 PCPs over a three-month period from November 2020 to January 2021. This study was approved by the Ethical Committee of the Université Claude Bernard Lyon 1 (Institutional Review Board N°2020-07-07-08, on July the 7th in 2020). We sent by e-mail a web link leading to our online ed- ucative path to all PCPs members of the URPS union of Auvergne/Rhone-Alpes region and Grand Est region hosted by Claroline®, the official educational website of Lyon 1 Claude Bernard University. It was first composed of a 10-clinical-case pre-test, followed by a 31-minute educative video (https://clarolineconnect.univ-lyon1.fr/resource/open/ file/4776658 in French) and lastly a distinct 10-case post-test. The link for the post-test was only available when the ap- plicant had validated the pre-test and completely watched the educative video. Pre- and post-test, for each case, in- cluded a multiple-choice question with pre-determined an- swers about management and a single choice question with pre-determined answer for the diagnostic orientation. Both pre- and post-test included distinct cases of one pigmented SUM, one amelanotic SUM, one SSCC, one trauma-induced nail change, one onychomycosis, one nail unit psoriasis, one SGCT, one nail case of alopecia areata, one periungual viral wart and one subungual hemorrhage. Management propos- als for each case were (one or more answer boxes could be ticked): “clinical follow-up”, “radiology imaging”, “myco- logical or bacteriological test”, “non-urgent dermatologist second opinion”, “orthopedic surgeon second opinion”, “podiatrist consultation”, “topical antifungal”, “other topi- cal treatment”, “systemic treatment”, and “urgent dermatol- ogist second opinion”. The diagnostic proposal for each case (only one answer box could be ticked) were the 10 conditions listed above. During the teaching video, all these conditions were covered by vocal explanations and images of several examples and five simple rules to improve diagnostic strat- egy in nail disease was taught : (1) thinking about nail tumor when a condition is monodactylic, (2) referring to derma- tologist for brown or black but also red or white-yellowish longitudinal nail band, (3) spontaneous nail plate erosion is not banal, (4) referring to dermatologist for non resolutive and painful nail condition and (5) evaluate the static and the dynamic of feet for toenail disease. The answers to the pre- and the post-test were pre-determined before the launch of the educative program by a consensus of nail diseases experts and were classified as “compulsory” (+15 points), “correct” (0 points), “ac- ceptable” (-5 point), “inappropriate” (-10 points) or “dan- gerous” (-30 points). An example of “compulsory” answer was an urgent dermatologist second opinion for pigmented or amelanotic SUM or podiatrist consultation in case of trauma-induced nail change. An example of “dangerous an- swer” was clinical follow-up for SSCC. For onychomycosis and psoriasis, no “dangerous” management were consid- ered. An example of “acceptable” answer was an orthopedic Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 3 surgeon second opinion for SUM, an example of “inappro- priate” answer was imaging for nail psoriasis. Although our study was more focused on the management of the cases, diagnostic orientation was also evaluated during pre- and post-tests. A correct answer was given 5 points. Rating for all answers was discussed with our biostatistician (GD). Some other common nail conditions were also briefly covered during the course (ingrown nail, pyogenic granu- loma, mucoid pseudocyst, ungual changes in systemic dis- ease, onychotillomania and some benign nail tumors). All cases shown during the pre-test were included in the teaching examples during the video course and expected answers to the questionnaire were then disclosed for each. Indeed, none of the cases used for the post-test were included in the video as examples. Study Population Participating PCPs were asked about their gender, age, geo- graphic setting (urban, suburban, or rural area), number of years after initial medical certification, attendance to post-university training session dermatology during the last 2 years. Although we had the results of the pre-test of all the enrolled population, we only retained for statistical analy- sis the 73 for whom we had the complete sequence of tests and training. The 65 PCPs who did not completed the entire study were only compared to the 73 others to determine if the two populations could be any different. Statistics Statistical analysis was performed by an independent biostat- istician (GD) who also reviewed the questionnaire before its online launch. Statistical unit was the PCP. Statistical anal- ysis was conducted using the IBM IPSS Statistic software, version 19 (IBM). Distribution comparisons were made by the Chi-2 test, Fisher test for qualitative variables, Student t test or paired Student t test for quantitative variables. P value <0.05 was considered significant. Results Training path web link was sent to 10,205 PCPs. One hun- dred and thirty-eight PCPs were initially enrolled in the study and finished the pre-test. However, only 73 (52.9%) among them completed the whole training program. Comparison with national statistics disclosed that our tested population, as usual in many medical surveys, included a slightly higher number of female (51/73 (69.3%); P = 0.0007) and younger (<40 years-old) (40/73 (54.7%); P = 1.0 10-12) PCPs than found in their general population in France. Comparing each PCP with himself, we demonstrated that the pre-test mean score was 15.2/20 and raised to 16.9/20 in the post-test (P = 2.25 10-18). Comparison of the pre-test scores of the participants who did not complete the whole training path to the others did not show significant difference. When comparing pre and post-test, the number of com- pulsory and correct answers was significantly higher in the post-test. For management, the correct answer (ie “clinical follow up”) raised from 6/73 (8.2%) to 19/73 (26%) in warts (P=0.002), from 16/73 (21.9%) to 33/73 (45.2%) in trauma-induced nail changes (P = 0.002; Table 1). A podiatrist consultation for trauma-induced nail changes was proposed in only 13/73 (17.8%) of the pre-test but raised to 55/73 (75.3%) in the post-test (P < 0.001). For pigmented SUM, 59/73 (80.3%) of PCPs required an urgent dermatologist second opinion in the pre-test whereas all recommended it 73/73 (100%) in the post-test (P < 0.001; Table 1). In onychomycosis, the choice of a systemic treatment was made by 16/73 (21.9%) PCPs in the pre-test while 54/73 (74%) prescribed it in the post-test (P < 0.001). For SGCT, the use of radiology imaging raised from 18/73 (24.7%) in the pre-test to 43/73 (58.9%) in the post-test (P < 0.001; Table 1). We also observed a decrease of using dangerous manage- ment in the post-test especially in malignant tumors. Seven dangerous managements were initially proposed in the pre- test (4/73 in SSCC, 2/73 in amelanotic SUM and 1/73 in pigmented SUM) then was reduced to 3 after completion of the training program (3/73 in amelanotic SUM), (P = 0.324; Table 3). The use of inappropriate/dangerous systemic treatment was reduced after the training program: from 4/73 (5.5%) to 1/73 (1.4%) in warts (P = 0.085); and from 18/73 (24.7%) to 10/73 (13.7%) in alopecia areata (P = 0.045; Table 3). A decrease in the unnecessary consumption of medical resources was also observed (Table 4). Mycological/bacte- riological tests decreased after the training program: from 29/73 (39.7%) to only 3/73 (4.1%) in warts (P < 0.001) and from 40/73 (54.8%) to 4/73 (5.5%) in trauma-induced nail changes (P < 0.001). Moreover, emergency referral (urgent second opinion) to dermatologists decreased from 20/73 (27.4%) to 5/73 (6.2%) (P < 0.001) and from 6/73 (8.2%) to 0% (P = 0.005) in subungual hemorrhage and alopecia areata respectively. Of note, the number of mycological/bacteriological tests slightly increased in the post-test (Table 4): 0/73 versus 7/73 (9.6%) in case of amelanotic SUM (P = 0.03). Similarly, the number of prescriptions of topical antifungals as well as the number of urgent dermatologist referrals slightly in- creased in the post-test in case of nail psoriasis (Table 4): 4/73 (5.5%) versus 1/73 (1.4%) (P = 0.085) and 2/73 (2.7%) versus 0/73 (P = 0.076) respectively, which was not statisti- cally significant. We can however observe that the post-test 4 Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 delay to initial treatment often long, from 15 months to 30 years [8,9]. SSCC, s also often diagnosed late, from 2 to 480 months (mean : 55 months) [10]. These important delays might be partially responsible of an apparent worse prognosis of SUM with a 33% overall survival rate at 15 years. Moreover, since conservative surgical treatments can be offered to early-stage SUM and SSCC, these delays could also result in a higher number of amputations and subse- quent disabilities [11,12]. Part of the problem could be initial wrong management strategies by PCPs [13]. However, little is known in the liter- ature about the global knowledge of PCPs about common or functionally important nail diseases [14-16]. For unknown reasons, the most widely acknowledged nail conditions by health professionals are fungal infections. Indeed, many ony- chomycoses do exist since it is claimed that about 10 to 50% of all nail diseases could be due to dermatophytic nail bed case of psoriasis nail could have been found more difficult to identify by the panel of PCPs since it was correctly diagnosed in only 45/73 (61.6%) versus 72/73 (98.6%) for the pre-test (P < 0.001) (Table 2). Lastly, in case of nail unit wart, the rate of urgent dermatologist referral increased from 12/73 (16.4%) to 23/73 (31.5%) (P = 0.015) after the training as well as the use of radiology imaging which increase from 3/73 (4.1%) to 13/73 (17.8%) (P = 0.003) (Table 4). Conclusions Most of the studies about SUM, SSCC and, to a lesser extent, SGCT, underline that diagnostic delay is often long and gen- erates losses of chance for curative and functional surgery in the two cancers and an unnecessary long delay towards func- tional and pain relief in the latter case. SUM is frequently discovered at advanced stage and the average reported Table 1. Pre-to-post-test evolution of correct or compulsory management answers in the panel. Correct or compulsory answers, N (%) P valueNail disorders Pre-test (N = 73) Post-test (N = 73) Wart Clinical follow-up 6 (8.2) 19 (26.0) 0.002 Trauma-induced nail change Clinical follow-up 16 (21.9) 33 (45.2) 0.001 Podiatrist consultation 13 (17.8) 55 (75.3) 0.001 Onychomycosis Mycological or bacteriological test 36 (49.3) 53 (72.6) 0.001 Non-urgent dermatologist second opinion 27 (37.0) 13 (17.8) 0.004 Systemic treatment 16 (21.9) 54 (74.0) < 0.001 Squamous cell carcinoma Radiology imaging 16 (21.9) 22 (30.1) 0.128 Urgent dermatologist second opinion 56 (76.7) 66 (90.4) 0.012 Amelanotic nail melanoma Radiology imaging 39 (53.4) 14 (19.7) <0.001 Urgent dermatologist second opinion 71 (97.3) 68 (93.2) 0.122 Glomus tumor Radiology imaging 18 (24.7) 43 (58.9) <0.001 Non-urgent dermatologist second opinion 43 (58.9) 41 (56.2) 0.369 Subungual hemorrhage Clinical follow-up 52 (71.2) 60 (82.2) 0.057 Pigmented subungual melanoma Urgent dermatologist second opinion 59 (80.3) 73 (100) <0.001 Alopecia areata Non-urgent dermatologist second opinion 53 (72.6) 61 (83,6) 0.053 Psoriasis Non-urgent dermatologist second opinion 58 (79.5) 60 (82,2) 0.337 Systemic treatment 11 (15.1) 10 (13,7) 0.407 Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 5 Table 3. Pre-to-post test evolution of “dangerous” management in the panel. “Dangerous” answer, N (%) P valuePre-test (N = 73) Post-test (N = 73) Wart Systemic treatment 4 (5.5) 1 (1.4) 0.085 Trauma-induced nail change Systemic treatment 5 (6.8) 0 0.010 Squamous cell carcinoma Clinical follow-up 2 (2.7) 0 0.076 Topical antifungal 0 0 NA Other topical treatment 1 (1.4) 0 0.157 Systemic treatment 1 (1.4) 0 0.157 Amelanotic nail melanoma Clinical follow-up 0 0 NA Non-urgent dermatologist second opinion 2 (2.7) 3 (4.1) 0.324 Topical antifungal 0 0 NA Other topical treatment 0 0 NA Systemic treatment 0 0 NA Glomus tumor Systemic treatment 0 0 NA Subungual hemorrhage Systemic treatment 0 0 NA Pigmented nail melanoma Clinical follow-up 1 (1.4) 0 0.157 Alopecia areata Systemic treatment 18 (24.7) 10 (13.7) 0.045 NA = not applicable. Table 2. Pre-to-post test evolution of correct diagnosis in the panel. Correct diagnosis, N (%) Pre-test (N = 73) Post-test (N = 73) P value Wart 19 (26.0) 31 (42.5) 0.017 Trauma-induced nail change 24 (32.9) 70 (95.9) <0.001 Onychomycosis 44 (60.3) 72 (98.9) <0.001 Squamous cell carcinoma 12 (16.4) 28 (38.4) 0.001 Amelanotic subungual melanoma 12 (16.4) 34 (46.6) <0.001 Glomus tumor 49 (67.1) 56 (76.7) 0.097 Subungual hemorrhage 53 (72.6) 68 (93.2) <0.001 Pigmented subungual melanoma 62 (84.9) 71 (97.3) 0.004 Alopecia areata 49 (67.1) 48 (65.8) 0.430 Psoriasis 72 (98.6) 45 (61.6) <0.001 invasion [17]. However, many authors believe that this con- dition is often not the primary nail disease and that many of them in fact complicate a pre-existing nail disease or injury [18]. Damaged nail by inflammatory nail disease like psoria- sis are often secondarily contaminated by dermatophytes that can subsequently be evidenced in the nail table by mycological laboratory tests [19,20]. Trauma-induced nail changes are much more common on toenails with the exception of on- ychotillomania. Evaluation of nail disease must always be done keeping in mind that any trouble of the foot static or any use of traumatizing shoes can result in nail injury and chronic changes too often confused with nail fungal infection. 6 Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 and painful nail condition and (5) evaluate the static and the dynamic of feet for toenail disease and eventually refer to a podiatrist. Our study showed a global poor level of knowledge with a relatively high frequency of inappropriate proposed man- agement. We also observed a misuse of medical resources in We believe that a wider diffusion of five simple rules can avoid many misdiagnoses: (1) thinking about nail tumor when a condition is monodactylic, (2) referring to derma- tologist for brown or black but also red or white-yellowish longitudinal nail band, (3) spontaneous nail plate erosion is not banal, (4) referring to dermalogist for non resolutive Table 4. Pre-to-post-test evolution of inappropriate use of medical resources in the panel. Incorrect answer, N (%) Pre-test (N = 73) Post-test (N = 73) P-value Wart Radiology imaging 3 (4.1) 13 (17.8) 0.003 Mycological or bacteriological test 29 (39.7) 3 (4.1) <0.001 Urgent dermatologist second opinion 12 (16.4) 23 (31.5) 0.015 Trauma-induced nail change Radiology imaging 0 0 NA Mycological or bacteriological test 40 (54.8) 4 (5.5) <0.001 Topical antifungal 37 (50.7) 1 (1.4) <0.001 Urgent dermatologist second opinion 1 (1.4) 1 (1.4) 0.500 Onychomycosis Radiology imaging 3 (4.1) 1 (1.4) 0.154 Orthopedic surgeon second opinion 0 0 NA Urgent dermatologist second opinion 4 (5.5) 2 (2.7) 0.202 Squamous cell carcinoma Mycological or bacteriological test 9 (12.3) 1 (1.4) 0.004 Amelanotic nail melanoma Mycological or bacteriological test 0 7 (9.6) 0.003 Glomus tumor Mycological or bacteriological test 1 (1.4) 0 0.157 Topical antifungal 0 0 NA Subungual hemorrhage Radiology imaging 6 (8.2) 2 (2.7) 0.071 Mycological or bacteriological test 1 (1.4) 0 0.157 Orthopedic surgeon second opinion 1 (1.4) 0 0.157 Urgent dermatologist second opinion 20 (27.4) 5 (5.8) <0.001 Pigmented nail melanoma Mycological or bacteriological test 1 (1.4) 0 0.157 Alopecia areata Radiology imaging 1 (1.4) 1 (1.4) 0.500 Mycological or bacteriological test 14 (19.2) 8 (11) 0.081 Topical antifungal 3 (4.1) 0 0.038 Urgent dermatologist second opinion 6 (8.2) 0 0.005 Psoriasis Radiology imaging 2 (2.7) 0 0.076 Topical antifungal 1 (1.4) 4 (5.5) 0.085 Urgent dermatologist second opinion 0 2 (2.7) 0.076 NA = not applicable. Original Article | Dermatol Pract Concept. 2023;13(3):e2023170 7 References 1. Lipner SR, Scher RK. Onychomycosis – a small step for qual- ity of care. Curr Med Res Opin. 2016;.;32(5):865-867. DOI: 10.1185/03007995.2016.1147026. PMID: 26807603. 2. Nguyen JT, Bakri K, Nguyen EC, Johnson CH, Moran SL. Sur- gical management of subungual melanoma: mayo clinic experi- ence of 124 cases. Ann Plast Surg. 2013;71(4):346-354. DOI: 10.1097/SAP.0b013e3182a0df64. PMID: 24025653. 3. Wollina U, Tempel S, Hansel G. Subungual melanoma: A single center series from Dresden. Dermatol Ther. 2019;32(5):e13032. DOI: 10.1111/dth.13032. PMID: 31344289. 4. Phan A, Touzet S, Dalle S, Ronger-Savlé S, Balme B, Thomas L. Ac- ral lentiginous melanoma: a clinicoprognostic study of 126 cases. Br J Dermatol. 2006;155(3):561-569. DOI: 10.1111/j.1365 -2133.2006.07368.x. PMID: 16911282. 5. Natarajan V, Nath AK, Thappa DM, Singh R, Verma SK. Coex- istence of onychomycosis in psoriatic nails: a descriptive study. 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Tips to treat the 5 most common nail disorders: brittle nails, onycholysis, paronychia, psoriasis, onychomycosis. Derma- tol Clin. 2015;33(2):175-183. DOI: 10.1016/j.det.2014.12.001. PMID: 25828710. many benign conditions. In our view, the rate of pre-test mis- diagnoses does not reflect the current practice of nail consul- tations in our department and cannot completely explain the observed management delays especially for nail unit cancers. This might be due to a recruitment bias since we cannot ex- clude that the volunteer participants chose to enter the study because of their specific interest in onychology. However, we observed significant improvement in the management strate- gies of most tested conditions. Some points could deserve a revision of our teaching strat- egy: more thorough training for amelanotic SUM seems to be necessary. However, this diagnosis often remains difficult even for trained dermatologists. High level of prescription of radiol- ogy imaging and urgent dermatology consultation in nail unit viral warts appears to be an unexpected unwanted effect of the sensibilization of our public about the diagnosis of SSCC. We do not consider this as a poor outcome of our training pro- gram since it is always better to insist on the possible malignant counterpart. Maybe an age and disease-duration threshold could be proposed in our teaching to help counter this effect. Our study has several possible biases. Our sample did not reflect the general population of French PCPs since women were overrepresented and our population was younger. This is a common finding in medical practice surveys and prob- ably reflect the greater interest for online educational tools of young health professionals, who are more often women in our country. As mentioned earlier, we cannot exclude a selection bias, yet our questionnaire revealed that only few of them had received a specific training in dermatology in general and on nail diseases during the two previous years. A framing bias cannot be excluded since our teaser message to enter the study specifically mentioned the risk of misdiagnos- ing nail unit cancer in general and SUM in particular. In conclusion, correct diagnosis of a nail disease can be delayed especially in primary care. Onychomycosis is often over-diagnosed, since there is a lot of commercial communi- cation about it. A short online training focusing on five simple rules significantly improved the management abilities of sev- eral nail conditions including life threatening ones by PCPs. Acknowledgements This work is supported in part by grants from Lyon 1 Uni- versity (to LT), the Hospices Civils de Lyon (to LT) and by the foundation “vaincre le mélanome” (to LT). 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