Abstract
Background
Recent studies have shown deficiencies in resident knowledge concerning transgender healthcare. However, there has not been an updated survey examining transgender healthcare training by medical residency directors. We assessed whether accredited residency programs in the United States and Canada were providing education on the healthcare needs of transgender patients.
Methods
We performed an exploratory descriptive survey study in 2022 of residency programs in the United States and Canada to assess residency education on transgender health using program directors listed in the website directory of the Accreditation Council for Graduate Medical Education.
Results
Out of 1680 residency program directors, 160 programs responded (response rate, 10%). Among the residency programs, education in transgender health was taught periodically throughout the curriculum (52.5%), in discrete modules (34.4%), or not taught at all (10.6%). However, 60% of residency program directors who responded reported that their program lacked any clinical rotation in which residents directly work with transgender patients. The most common areas of transgender care omitted from residency education on transgender health were barriers associated with chronic illness and mental health.
Conclusion
There remains a need for robust transgender medical training in residency programs through clinical rotations on transgender health.
Keywords: Accreditation Council for Graduate Medical Education, graduate medical education, transgender health, undergraduate medical education
Recent studies have indicated deficiencies in resident knowledge concerning the healthcare needs of transgender patients.1–3 A survey of medical school deans in the United States and Canada showed that few hours of residency training were dedicated to addressing health issues of the transgender community.1–3 Furthermore, the quantity, content, and perceived quality of instruction on transgender health varied substantially in the academic programs,1–3 despite the fact that transgender individuals face substantial challenges in the healthcare system.1,2,4–10 In contrast to undergraduate medical education, residency programs may have an opportunity to help correct the deficiencies in treatment of transgender patients through increased education. The American Academy of Medical Colleges provided a roadmap for education on transgender healthcare in 2015.11 Literature from the areas of medical humanities and ethics suggests the deficient treatment of transgender patients mandates a deeper understanding of transgender healthcare, requiring knowledge of the social construction of illness.12 This disparity in transgender healthcare is likely due to several causes, including lack of provider education during residency, lack of faculty who are comfortable and willing to teach transgender healthcare, and lack of perceived need to offer education on this topic.3
There has been only one study on undergraduate education on transgender health education. This survey from 2011 examined the current state of education in transgender health in the United States and Canada. However, there has not been a survey investigating the content of transgender healthcare in Accreditation Council for Graduate Medical Education (ACGME)-accredited residency programs. Therefore, we conducted a national survey of family medicine, internal medicine, obstetrics and gynecology, pediatrics, psychiatry, and urology residency program directors at all ACGME-accredited programs in the United States and Canada. The survey aimed to ascertain what is currently being taught in residencies about transgender health issues and the receptivity of faculty to this teaching. The data provide insight into whether education in transgender health has expanded in residency programs or remained the same.
Methods
Approval for this survey study was given by the institutional review board at Texas Tech University Health Sciences Center, Lubbock, Texas (FWA #00006767 TTUHSC Lubbock/Odessa IRB #00000096). Informed consent was also obtained.
The study population consisted of US and Canadian residency programs in specific specialties, obtained from the ACGME website (https://apps.acgme.org/ads/public/; accessed 8/28/2020). The list included 120 programs in family medicine, 140 programs in internal medicine, 220 programs in obstetrics, 320 programs in pediatrics, 400 programs in psychiatry, and 480 programs in urology. Therefore, a total of 1,680 email invitations were sent to the residency directors from the aforementioned programs with a link to the survey. For a response rate of 10%, 168 responses were required to have an adequate sample size for meaningful analysis. Our study excluded residency programs not in the United States or Canada or not ACGME accredited, as well as residents, medical students, nurses, and healthcare professionals other than residency directors.
We utilized a modified version of the 2011 JAMA survey to assess education in transgender health in various specialties and residency programs.3 The original JAMA survey was directed toward deans of undergraduate medical education. We modified question wording to focus on residency program directors for ACGME-accredited residency programs. Specifically, the questions used in the survey were designed to collect information in the following areas:
Affiliation of program: allopathic, osteopathic, or private/nonacademic
The amount of time dedicated to teaching transgender content during the residency
How the content on specific aspects of transgender health was dispersed during the residency training and characteristics of the training (lectures, small group sessions, whether a clinical rotation was specifically dedicated to transgender patient care, whether faculty development was offered on transgender health)
Specific subjects included in the curriculum on transgender patient care
Perceptions of the survey respondents on the amount of coverage of specific transgender patient care subjects in their residency program
Methods of evaluation of the efficacy of education in transgender health at the respondents’ institutions/programs
Respondents’ assessment of strategies for increasing transgender-specific content at their institutions/programs
The full questionnaire appears in the Supplemental Material.
Each subject’s responses were collected anonymously. Thirty days were allowed for responses, after which a follow-up email for additional responses was sent. The survey was closed after 60 days. Data were collected using the Qualtrics survey program.
Since this was an exploratory descriptive survey study, data were summarized in descriptive statistics as means with standard deviations and counts with percentages as appropriate based on the examined variable level of measurement. Pearson’s chi square test was used to examine the associations between categorical variables, and a one-way ANOVA test was used to examine group differences on continuous-level variables (total hours dedicated to teaching transgender content by program type). A P value < 0.05 was considered statistically significant.
Results
A total of 160 residency program directors from 108 allopathic (MD-granting), 18 osteopathic (DO-granting), and 34 private/nonacademic programs responded to the survey. The full results are shown in the Supplemental Material. The survey response rate for the survey was approximately 10%. Based on the participants’ responses, the average amount of time spent on transgender health topics was 10.7 hours (Table 1). There was no statistically significant difference in resident training hours between private, allopathic, or osteopathic graduate medical residency programs (Supplemental Material). Among the residency programs, education in transgender health was taught periodically throughout the curriculum (52.5%), in discrete modules (34.4%), or not taught at all (10.6%). Furthermore, 63.1% of residency program directors had required lectures or small-group sessions that directly addressed transgender-specific health issues in the clinical curriculum. However, 60% of residency program directors reported that their program lacked any clinical rotation for residents to directly work with transgender patients. In addition, only 36.9% of faculty reported that their program provided faculty members teaching development opportunities to learn more about transgender health. Among the various methods for feedback on mastering transgender health, only 14.1% used patient evaluations. Most residency directors reported that peer-to-peer evaluations were the most common form of feedback for residents on transgender health (38.5%).
Table 1.
Hours of education in transgender health for private, allopathic, and osteopathic graduate residency programs
| Program | N | Mean (hours) | Standard deviation | Standard error | 95% CI for mean |
Min | Max | |
|---|---|---|---|---|---|---|---|---|
| Lower bound | Upper bound | |||||||
| MD-granting | 108 | 10.269 | 17.2879 | 1.6635 | 6.971 | 13.566 | 0.0 | 120.0 |
| DO-granting | 18 | 10.444 | 14.4150 | 3.3976 | 3.276 | 17.613 | 0.0 | 50.0 |
| Private/nonacademic | 34 | 12.156 | 18.1227 | 3.1080 | 5.833 | 18.479 | 0.0 | 100.0 |
| Total | 160 | 10.689 | 17.0908 | 1.3511 | 8.021 | 13.358 | 0.0 | 120.0 |
As shown in Figure 1, residency directors most frequently reported chronic disease risks, body image, drug use, unhealthy relationships, and coming out as areas of omission in their curriculum on transgender health. In contrast, residents received extensive training in most programs on understanding gender identity, access to care for transgender patients, transitioning, mental health issues, and HIV infections among transgender patients. Despite differences in content area, there was consistent agreement among residency directors (30%–50%) that many areas of transgender health receive too little coverage for residents (Figure 2). A subgroup analysis of allopathic, osteopathic, and private/nonacademic programs found no significant difference in residency director assessments of transgender healthcare opportunities or coverage among resident trainees.
Figure 1.
Content areas in transgender education that are not required for resident training, as reported by program directors.
Figure 2.
Areas in transgender education that receive too little coverage, as reported by program directors.
As shown in Figure 3, the most common interventions suggested by residency directors to improve transgender-specific medicine included (1) curricular material focusing on transgender-related health/health disparities; (2) clinical faculty willing and able to teach transgender-related curricular content; (3) more time in the curriculum to be able to teach transgender-related content; and (4) more evidence-based research on transgender health/health disparities. Among the different transgender health content areas surveyed, the main content areas that did not have content provided in discussing transgender care included barriers to accessing medical care for transgender people, chronic disease risk for transgender people, mental health in transgender people, and body image in transgender people (Table 2).
Figure 3.
Residency director strategies to increase transgender-specific content, with bars showing percentage of program directors in agreement.
Table 2.
Binomial analysis of transgender healthcare content at residency programs
| N | Observed prop. | Exact sig. (2-tailed) | ||
|---|---|---|---|---|
| Transgender-specific content | Taught | 139 | .87 | <.001 |
| Not taught | 21 | .13 | ||
| Total | 160 | 1.00 | ||
| Lectures or small-group sessions that include transgender-specific content | No small group | 10 | .06 | <.001 |
| Small group | 150 | .94 | ||
| Total | 160 | 1.00 | ||
| Clinical rotation to facilitate transgender patient care | No rotation | 101 | .63 | .001 |
| Rotation | 59 | .37 | ||
| Total | 160 | 1.00 | ||
| Faculty development for teaching about transgender health | No faculty development | 40 | .26 | <.001 |
| Faculty development | 113 | .74 | ||
| Total | 153 | 1.00 | ||
| Barriers to accessing medical care for transgender people | No content | 62 | .44 | .153 |
| Content | 80 | .56 | ||
| Total | 142 | 1.00 | ||
| Alcohol, tobacco, or other drug use among transgender people | No content | 56 | .38 | .006 |
| Content | 90 | .62 | ||
| Total | 146 | 1.00 | ||
| Safer sex for transgender people | No content | 97 | .66 | <.001 |
| Content | 50 | .34 | ||
| Total | 147 | 1.00 | ||
| Sexually transmitted infections (not HIV) in transgender people | No content | 99 | .68 | <.001 |
| Content | 46 | .32 | ||
| Total | 145 | 1.00 | ||
| HIV in transgender people | No content | 57 | .41 | .034 |
| Content | 83 | .59 | ||
| Total | 140 | 1.00 | ||
| Chronic disease risk for transgender populations | No content | 68 | .47 | .507 |
| Content | 77 | .53 | ||
| Total | 145 | 1.00 | ||
| Coming out | No content | 120 | .77 | <.001 |
| Content | 35 | .23 | ||
| Total | 155 | 1.00 | ||
| Gender identity | No content | 40 | .27 | <.001 |
| Content | 110 | .73 | ||
| Total | 150 | 1.00 | ||
| Transitioning (e.g., male-to-female, female-to-male) | No content | 56 | .38 | .003 |
| Content | 93 | .62 | ||
| Total | 149 | 1.00 | ||
| Sex reassignment surgery | No content | 61 | .40 | .018 |
| Content | 91 | .60 | ||
| Total | 152 | 1.00 | ||
| Transgender adolescent health | No content | 43 | .28 | <.001 |
| Content | 109 | .72 | ||
| Total | 152 | 1.00 | ||
| Mental health in transgender people | No content | 62 | .42 | .069 |
| Content | 85 | .58 | ||
| Total | 147 | 1.00 | ||
| Body image in transgender people | No content | 63 | .44 | .156 |
| Content | 81 | .56 | ||
| Total | 144 | 1.00 | ||
| Unhealthy relationships (e.g., intimate partner violence) among transgender people | No content | 146 | .91 | <.001 |
| Content | 14 | .09 | ||
| Total | 160 | 1.00 | ||
Many residency directors reported the need for specific training on caring for transgender patients in minority populations (BIPOC—Black, Indigenous, and People of Color), incarcerated transgender patients, and transgender patients in the military. Most residency directors reported greater need for advanced training in transgender patients on hormone therapy, surgeries, mental health treatment, social support, fertility treatment, risk for infections, and health screenings. To address this need, several residency directors reported that their programs required training sessions, rotations, or clinical encounter simulations to provide their resident trainees experience treating transgender patients. However, residency directors reported that barriers to achieving these goals need to be addressed. For example, one residency director reported that their hospital system, which is associated with a Catholic institution, discourages transgender healthcare or training to directly address the barriers of care to this population.
Discussion
The total number of hours in residency training dedicated to transgender healthcare was greater than the amount of time reported by undergraduate medical deans in the 2011 JAMA survey by Obedin-Maliver et al.3 The increased amount of time spent on transgender healthcare in graduate medical education compared with undergraduate medical education is likely related to the direct clinical exposure and responsibility of resident trainees for the care of transgender patients, particularly with regards to initiating hormone replacement therapy and other medical concerns in this patient population. Similar to Obedin-Maliver et al’s study,3 this survey also did not find a statistically significant difference in the number of hours dedicated to education in transgender health between private, allopathic, or osteopathic residencies. The top five areas of deficient content areas in transgender healthcare were related to training on transitioning, body image, sex reassignment surgery, chronic disease risk, and substance use among transgender patients. According to this survey, the results were similar to those of Obedin-Maliver et al, with most residency directors reporting body image, drug use, and chronic disease risks among transgender patients as content areas deficient in their residency training program. Specifically, chronic illnesses, such as HIV and mental health, as well as barriers to accessing medical care for transgender people were content areas that were frequently overlooked in these residency programs. In addition, the residency directors in this survey reported that topics on unhealthy relationships and coming out were discussed less frequently than in the JAMA study.3 Overall, there is a lack of training in both undergraduate and graduate medical education with regards to addressing barriers to medical care and chronic illnesses, including mental health, among transgender patients. Given the restrictions in some states to transgender healthcare, the lack of content focused on chronic illnesses and access to care remains an area in graduate medical training that should be added and/or expanded in current residency training programs as well as undergraduate studies on transgender healthcare.13,14
With regards to strategies to increase LGBTQ-related content in the graduate medical education curriculum, respondents in both the JAMA study and this survey suggested adopting curricular material focusing on transgender-related health/health disparities, greater faculty involvement teaching transgender-related curricular content, and more clinical and academic time dedicated to transgender-related content with a particular focus on evidence-based research on transgender health/health disparities. This is particularly the case with regards to handling chronic illnesses among transgender patients and overcoming institutional barriers that may discourage training in transgender healthcare due to lack of resources, training, or other social factors (e.g., religion and politics). As such, there is a greater need to invest and divert further academic and clinical resources to expand transgender clinical education to residents across private, allopathic, and osteopathic graduate medical education residency programs. This is particularly important with introducing transgender medical education early in undergraduate medical education to help lay the foundations of transgender healthcare that can be built upon through graduate medical training programs. Together, these results indicate that there remains a widespread lack of transgender healthcare training in both graduate and undergraduate medical education programs in the United States and Canada.
Current status of transgender healthcare in the United States and Canada
Despite efforts to increase LGBTQ content in medical education, there are still large knowledge gaps on transgender patients.3,15–17 The inability of clinical faculty members to teach transgender-related material is another barrier toward improving training on transgender health for medical students and residents.15 Furthermore, lectures on transgender health education are typically quick sessions that cover sexual health among LGBTQ patients, focusing primarily on the transmission of sexually transmitted diseases, such as HIV.16 This is further compounded by the lack of dedicated clinical settings, preceptors, or leadership to train medical students and residents in transgender care. Additionally, many medical and residency programs lack funding to directly address the gap in resources toward training future physicians in transgender health. Currently, the ACGME does not consider education in transgender health as a required component of residency education programs. The absence of transgender-specific health needs from many medical school and residency curricula also contributes to health inequalities among transgender communities.16 However, little content is directed toward mental health or other socioeconomic disparities faced by the transgender community.3,15,17–19 In contrast, more directed educational initiatives, such as lectures delivered during clinical clerkships, increase medical students’ understanding and comfort discussing health issues with transgender patients.15,17,20–23
Similar results were observed in a systematic review on transgender health training among medical students and residents.1,2 The greatest improvement in medical students’ and residents’ confidence and knowledge on transgender health was achieved through practice (clerkships and rotations) or mock practice (role play, case studies, and standardized patients) rather than didactic lectures alone.1,2 Despite these results, there is a lack of long-term studies on the impact of transgender-specific health training on patient outcomes.1,2 In addition, none of the available studies included cross-sectional, longitudinal, case-control, randomized controlled, or retrospective experimental designs to evaluate the impact of affirming and inclusive care training modalities on knowledge.1,2 There are also disagreements over the optimum educational intervention formats and timing to support learning about transgender healthcare among medical students and residents.2 This is further complicated by the meshwork of different intervention modalities used to train medical students and residents.2
Limitations
Although this survey achieved the desired survey response rate, our sample size was small. A larger sample size of residency program directors may provide additional information on deficiencies and preferred interventions depending on the type of residency program. In addition, we were not able to perform a subgroup analysis based on residency program subspecialty due to the sample size of our survey. Furthermore, our study did not examine resident trainees and whether exposure to education in transgender health in their undergraduate training provided additional benefit to their care of transgender patients. Assessing and comparing resident trainee and director perspectives on transgender healthcare content and application would be beneficial toward directing effective interventions at improving transgender healthcare training for future trainees. Lastly, our survey compared transgender healthcare training between graduate and undergraduate medical education. Further studies that examine changes in both graduate and undergraduate medical education training would help monitor how education in transgender health is applied across medical training.
Conclusion
Overall, there remains a need to improve transgender medical training in graduate medical education. Current residency programs focus a greater proportion of their transgender healthcare coverage on medical issues of transgender patients without a greater appreciation of unique behavioral challenges and perspectives. Further incorporation of transgender patients in the evaluation and training of residents may provide a unique opportunity to build relationships with LGBTQ patients and improve resident interactions with this patient population. Additional clinical rotations and faculty development opportunities for continued transgender health training may further address the lack of transgender health coverage. Future investigations into education in transgender health should focus on (1) metropolitan vs nonmetropolitan training; (2) geographic location of training (North vs South, Coastal vs Midwest or inland); (3) size of training program (university or tertiary center vs nonuniversity setting or secondary center); (4) affiliation of training (religious organization affiliation vs nonreligious affiliation).
Supplementary Material
Disclosure statement
The authors report no funding or conflicts of interest.
References
- 1.Cooper RL, Ramesh A, Radix AE, et al. Affirming and inclusive care training for medical students and residents to reducing health disparities experienced by sexual and gender minorities: a systematic review. Transgen Health. 2022. doi: 10.1089/trgh.2021.0148. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Nolan IT, Blasdel G, Dubin SN, Goetz LG, Greene RE, Morrison SD.. Current state of transgender medical education in the United States and Canada: update to a scoping review. J Med Educ Curric Dev. 2020;7:2382120520934813. doi: 10.1177/2382120520934813. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Obedin-Maliver J, Goldsmith ES, Stewart L, et al. Lesbian, gay, bisexual, and transgender-related content in undergraduate medical education. JAMA. 2011;306(9):971–977. doi: 10.1001/jama.2011.1255. [DOI] [PubMed] [Google Scholar]
- 4.Liang JJ, Gardner IH, Walker JA, Safer JD.. Observed deficiencies in medical student knowledge or transgender and intersex health. Endocr Pract. 2017;23(8):897–906. doi: 10.4158/EP171758.OR. [DOI] [PubMed] [Google Scholar]
- 5.Reisner SL, Hughto JM, Dunham EE, et al. Legal protections in public accommodations settings: a critical public health issue for transgender and gender-nonconforming people. Milbank Q. 2015;93(3):484–515. doi: 10.1111/1468-0009.12127. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Streed CG Jr, McCarthy EP, Haas JS.. Association between gender minority status and self-reported physical and mental health in the United States. JAMA Intern Med. 2017;177(8):1210–1212. doi: 10.1001/jamainternmed.2017.1460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Herbst JH, Jacobs ED, Finlayson TJ, McKleroy VS, Neumann MS, Crepaz N, HIV/AIDS prevention research synthesis team . Estimating HIV prevalence and risk behaviors of transgender persons in the United States: a systematic review. AIDS Behav. 2008;12(1):1–17. doi: 10.1007/s10461-007-9299-3. [DOI] [PubMed] [Google Scholar]
- 8.Radix A, Sevelius J, Deutsch MB.. Transgender women, hormonal therapy and HIV treatment: a comprehensive review of the literature and recommendations for best practices. J Int AIDS Soc. 2016;19(3):20810. doi: 10.7448/IAS.19.3.20810. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Operario D, Nemoto T.. HIV in transgender communities: syndemic dynamics and a need for multicomponent interventions. J Acquir Immune Defic Syndr. 2010;55(Suppl 2):S91–S93. doi: 10.1097/QAI.0b013e3181fbc9ec. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Clements-Nolle K, Marx R, Guzman R, Katz M.. HIV prevalence, risk behaviors, health care use, and mental health status of transgender persons: implications for public health intervention. Am J Public Health. 2001;91(6):915–921. doi: 10.2105/AJPH.91.6.915. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Rubin R. Minimizing health disparities among LGBT patients. JAMA. 2015;313(1):15–17. doi: 10.1001/jama.2014.17243. [DOI] [PubMed] [Google Scholar]
- 12.Kessler SJ. The medical construction of gender: case management of intersex infants. Signs. 1990;16(1):3–26. doi: 10.1086/494643. [DOI] [Google Scholar]
- 13.Liu M, Sandhu S, Keuroghlian AS.. Achieving the triple aim for sexual and gender minorities. N Engl J Med. 2022;387(4):294–297. doi: 10.1056/NEJMp2204569. [DOI] [PubMed] [Google Scholar]
- 14.Malina S, Warbelow S, Radix AE.. Two steps back – rescinding transgender health protections in risky times. N Engl J Med. 2020;383(21):e116. doi: 10.1056/NEJMp2024745. [DOI] [PubMed] [Google Scholar]
- 15.Click IA, Mann AK, Buda M, et al. Transgender health education for medical students. Clin Teach. 2020;17(2):190–194. doi: 10.1111/tct.13074. [DOI] [PubMed] [Google Scholar]
- 16.Dubin SN, Nolan IT, Streed CG Jr, Greene RE, Radix AE, Morrison SD.. Transgender health care: improving medical students’ and residents’ training and awareness. Adv Med Educ Pract. 2018;9:377–391. doi: 10.2147/AMEP.S147183. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Sequeira GM, Chakraborti C, Panunti BA.. Integrating lesbian, gay, bisexual, and transgender (LGBT) content into undergraduate medical school curricula: a qualitative study. Ochsner J. 2012;12(4):379–382. [PMC free article] [PubMed] [Google Scholar]
- 18.Mandap M, Carrillo S, Youmans SL.. An evaluation of lesbian, gay, bisexual, and transgender (LGBT) health education in pharmacy school curricula. Curr Pharm Teach Learn. 2014;6(6):752–758. doi: 10.1016/j.cptl.2014.08.001. [DOI] [Google Scholar]
- 19.Lim F, Johnson M, Eliason M.. A national survey of faculty knowledge, experience, and readiness for teaching lesbian, gay, bisexual, and transgender health in baccalaureate nursing programs. Nurs Educ Perspect. 2015;36(3):144–152. doi: 10.5480/14-1355. [DOI] [Google Scholar]
- 20.Dowshen N, Nguyen GT, Gilbert K, Feiler A, Margo KL.. Improving transgender health education for future doctors. Am J Public Health. 2014;104(7):e5–e6. doi: 10.2105/AJPH.2014.301978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Park JA, Safer JD.. Clinical exposure to transgender medicine improves students’ preparedness above levels seen with didactic teaching alone: a key addition to the Boston University model for teaching transgender healthcare. Transgen Health. 2018;3(1):10–16. doi: 10.1089/trgh.2017.0047. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Sanchez NF, Rabatin J, Sanchez JP, Hubbard S, Kalet A.. Medical students’ ability to care for lesbian, gay, bisexual, and transgendered patients. Fam Med. 2006;38(1):21–27. [PubMed] [Google Scholar]
- 23.Mason-Suares H, Sweetser DA, Lindeman NI, Morton CC.. Training the future leaders in personalized medicine. J Pers Med. 2016;6(1):1. doi: 10.3390/jpm6010001. [DOI] [PMC free article] [PubMed] [Google Scholar]
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