Journals / Kırklareli Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi / 2026 / Cilt: 14 Sayı: 1

Determinants and Consequences of After-Hours Work-Related Communication: A Systematic Review

Mesai Saatleri Dışı İşle İlgili İletişimin Belirleyicileri ve Sonuçları: Bir Sistematik Derleme

Merve Gerçek(KOCAELİ ÜNİVERSİTESİ, HEREKE ÖMER İSMET UZUNYOL MESLEK YÜKSEKOKULU)0000-0002-7076-8192
Pages
40–71
Publication Date
2025-03-27
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Through an analysis of 31 empirical studies following PRISMA protocol, findings indicate that after-hours work-related communication frequently results in adverse effects, including stress, anxiety, fatigue, diminished job satisfaction, and work-family conflict.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Developments in information and communication technologies have facilitated work-related communication with managers and colleagues independent of time and location.
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Key Findings & Data:Through an analysis of 31 empirical studies following PRISMA protocol, findings indicate that after-hours work-related communication frequently results in adverse effects, including stress, anxiety, fatigue, diminished job satisfaction, and work-family conflict.
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Conclusion & Impact:This review offers critical insights for managers, employees, human resource professionals, and researchers, serving as a guide to effectively manage after-hours work-related communication while reducing its negative implications.
🔬Design:Review & Systematic Survey
📍Scope:Comprehensive Sample
⚙️Variables:Mesai saatleri dışı işle ilgili iletişim · mesai sonrası bağlantı · bilgi ve iletişim teknolojileri

Abstract

Developments in information and communication technologies have facilitated work-related communication with managers and colleagues independent of time and location. However, engaging in such communication beyond regular working hours often blurs the boundaries between professional and personal life, resulting in continuous mental engagement with work. This phenomenon disrupts recovery processes and frequently leads to negative outcomes such as stress, fatigue, and reduced job satisfaction. On the other hand, some studies emphasize the potential advantages of spatial flexibility, suggesting after-hours work-related communication enables employees to manage personal responsibilities. To explore these dynamics, a systematic review was conducted to identify the conditions under which after-hours work communication leads to positive or negative outcomes for employees. Through an analysis of 31 empirical studies following PRISMA protocol, findings indicate that after-hours work-related communication frequently results in adverse effects, including stress, anxiety, fatigue, diminished job satisfaction, and work-family conflict. However, findings also show that after-hours work-related communication has the potential to enhance employee innovativeness and increase work-life flexibility in specific contexts. This review offers critical insights for managers, employees, human resource professionals, and researchers, serving as a guide to effectively manage after-hours work-related communication while reducing its negative implications.

Özet

Bilgi ve iletişim teknolojilerinde yaşanan gelişmeler, çalışanların zaman ve mekândan bağımsız bir şekilde yöneticiler ve iş arkadaşlarıyla işle ilgili iletişime geçebilmesini sağlamıştır. Ancak bu iletişim süreçlerinin rutin mesai saatleri dışında gerçekleşmesi, çeşitli iş taleplerinin bireysel özel alana taşmasına yol açarak çalışanlarda zihinsel olarak sürekli işe bağlı kalmaya, iş sonrası yenilenmeyi engelleyerek stres ve yorgunluk gibi olumsuz sonuçlara yol açabilmektedir. Diğer yandan mesai saatleri dışında telekomünikasyon araçlarıyla işle ilgili iletişim olanaklarının bulunmasının sağladığı mekânsal özgürlüğün, özel yaşam taleplerini daha iyi yönetmeyi sağladığına yönelik görüşler de bulunmaktadır. Bu bağlamda hangi durumlarda mesai dışı işle ilgili iletişimin olumlu veya olumsuz çalışan çıktılarına yol açtığını anlayabilmek ve bu konudaki araştırmaların mevcut durumunu belirleyebilmek amacıyla bir sistematik derleme yapılmıştır. PRISMA protokolü çerçevesinde çalışmaya dahil edilen 31 görgül makalenin incelenmesi sonucunda mesai saatleri dışında işle ilgili iletişimin stres, kaygı, yorgunluk, düşük iş tatmini, iş ve aile çatışması gibi olumsuzluklara yol açabildiği belirlenmiştir. Ayrıca mesai saatleri dışı işle ilgili iletişimin çalışan yenilikçiliğini arttırabileceği ve iş-özel yaşam esnekliği sağlayabileceğine yönelik bulgular da mevcuttur. Bu derleme, yöneticiler, çalışanlar, insan kaynakları uzmanları ve araştırmacılar için mesai saatleri dışında işle ilgili iletişimi etkili bir şekilde yönetmeye ve bu iletişim türünün olumsuz etkilerini azaltmaya yönelik önemli bilgiler sunmaktadır.

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Cite This Article

Gerçek, M. (2025). Determinants and Consequences of After-Hours Work-Related Communication: A Systematic Review. Kırklareli Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi, Cilt: 14 Sayı: 1, 40–71. https://doi.org/10.53306/klujfeas.1590150

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References (71)

  1. Aljabr, N., Chamakiotis, P., Petrakaki, D., & Newell, S. (2022). After‐hours connectivity management strategies in academic work. New Technology, Work and Employment, 37(2), 185-205. https://doi.org/10.1111/ntwe.12217
  2. Ashforth, B. E., Kreiner, G. E., & Fugate, M. 2000. All in a day’s work: Boundaries and micro role transitions. Academy of Management Review, 25, 472-491. https://doi.org/10.5465/amr.2000.3363315
  3. Baumeister V. M., Kuen L. P., Bruckes M., Schewe G. (2021). The relationship of work-related ICT use with well-being, incorporating the role of resources and demands: A meta-analysis. Sage Open, 11(4), 21582440211061560. https://doi.org/10.1177/21582440211061560
  4. Baumeister, R. F., Bratslavsky, E., Muraven, M., & Tice, D. M. (2018). Ego depletion: Is the active self a limited resource?. In Self-regulation and self-control (pp. 16-44). Routledge.
  5. BBC (2024, Kasım). French workers get 'right to disconnect' from emails out of hours, https://www.bbc.com/news/world-europe-38479439 adresinden erişilmiştir.
  6. Boswell, W. R., & Olson-Buchanan, J. B. (2007). The use of communication technologies after hours: The role of work attitudes and work-life conflict. Journal of Management, 33(4), 592-610.
  7. Boswell, W. R., Olson-Buchanan, J. B., Butts, M. M., & Becker, W. J. (2016). Managing “after hours” electronic work communication. Organizational Dynamics, 45(4), 291-297. https://doi.org/10.1016/j.orgdyn.2016.10.004
  8. Chen, A., & Casterella, G. I. (2018). After-hours work connectivity: Technological antecedents and implications. IEEE Transactions on Professional Communication, 62(1), 75-93. https://doi.org/10.1109/TPC.2018.2867129
  9. Cheng, K., Cao, X., Guo, L., & Xia, Q. (2022). Work connectivity behavior after-hours and job satisfaction: examining the moderating effects of psychological entitlement and perceived organizational support. Personnel Review, 51(9), 2277-2293. https://doi.org/10.1108/PR-06-2020-0413
  10. Chu, F., Zhang, J., Pellegrini, M. M., Wang, C., & Liu, Y. (2024). Staying connected beyond the clock: a talent management perspective of after-hours work connectivity and proactive behaviours in the digital age. Management Decision.Vol. ahead-of-print No. ahead-of-print. https://doi.org/10.1108/MD-07-2023-1186
  11. Çankır, E., Çiğdem, M., Zaralioğlu, F. B.(2024). Sağlık Çalışanlarında İş Motivasyonunun İş Performansı Üzerindeki Etkisinde Çalışmaya Tutkunluğun ve İşyerinde Can Sıkıntısının Aracılık Rolü, İşletme Araştırmaları Dergisi, 16(3), 1313-1329. https://doi.org/10.20491/isarder.2024.1857
  12. Desrochers, S., & Dahir, V. (2000). Ambition as a motivational basis of organizational and professional commitment: Preliminary analysis of a proposed career advancement ambition scale. Perceptual and Motor Skills, 91, 563-570. https://doi.org/10.2466/pms.2000.91.2.563
  13. Diaz I., Chiaburu D. S., Zimmerman R. D., Boswell W. R. (2012). Communication technology: Pros and cons of constant connection to work. Journal of Vocational Behavior, 80(2), 500–508. https://doi.org/10.1016/j.jvb.2011.08.007
  14. Dong, M., Zhang, T., Li, Y., & Ren, Z. (2022). The effect of work connectivity behavior after-hours on employee psychological distress: the role of leader workaholism and work-to-family conflict. Frontiers in Public Health, 10, 722679. https://doi.org/10.3389/fpubh.2022.722679
  15. Elmas-Atay, S., & Gerçek, M. (2021). İş-yaşam çatışmasının Koronavirüs (COVID-19) pandemisi sürecinde yeniden değerlendirilmesi: Kadın akademisyenler açısından nitel bir araştırma. Balıkesir Üniversitesi Sosyal Bilimler Enstitüsü Dergisi, 24(45), 203-241. https://doi.org/10.31795/baunsobed.865298
  16. Fenner, G. H., & Renn, R. W. (2004). Technology‐assisted supplemental work: Construct definition and a research framework. Human Resource Management: Published in Cooperation with the School of Business Administration, The University of Michigan and in alliance with the Society of Human Resources Management, 43(2‐3), 179-200. https://doi.org/10.1002/hrm.20014
  17. Fujimoto, Y., Ferdous, A. S., Sekiguchi, T., and Sugianto, L. F. (2016). The effect of mobile technology usage on work engagement and emotional exhaustion in Japan. Journal of Business Research, 69, 3315–3323. https://doi.org/10.1016/j.jbusres.2016.02.013
  18. Gadeyne, N., Verbruggen, M., Delanoeije, J., & De Cooman, R. (2018). All wired, all tired? Work-related ICT-use outside work hours and work-to-home conflict: The role of integration preference, integration norms and work demands. Journal of Vocational Behavior, 107, 86-99. https://doi.org/10.1016/j.jvb.2018.03.008
  19. Gerçek, M. (2018). Yöneticilerin babacan (paternalist) liderlik davranışlarının psikolojik sözleşme bağlamındaki beklentileri üzerindeki etkilerine yönelik bir çalışma. Eskişehir Osmangazi Üniversitesi İktisadi ve İdari Bilimler Dergisi, 13(2), 101-118. https://doi.org/10.17153/oguiibf.390533
  20. Gerçek, M., & Özveren, C. G. (2023). Yapay zekâ araçları İKY için nasıl değer yaratabilir? Çalışan duygu analizinin uygulama alanlarının incelenmesi. Yönetim Bilimleri Dergisi, 21(50), 1048-1076. https://doi.org/10.35408/comuybd.1285706
  21. Greenhaus, J. H., & Beutell, N. J. 1985. Sources of conflict between work and family roles. Academy of Management Review,10, 76-88. https://doi.org/10.5465/amr.1985.4277352
  22. Hobfoll, S. E. (1989). Conservation of resources: a new attempt at conceptualizing stress. American Psychologist, 44(3), 513. https://doi.org/10.1037/0003-066X.44.3.513
  23. Hu, Y., Kuang, T., & Lu, Y. (2024). The effect of work connectivity behavior after-hours on emotional exhaustion: The role of psychological detachment and work-family segmentation preference. SAGE Open, 14(3), 21582440241281417. https://doi.org/10.1177/21582440241281417
  24. Huo, W., Xu, X., Li, X., Xie, J., & Sun, L. (2023). Work-related use of information and communication technologies after-hours (W_ICTs) and employee innovation behavior: a dual-path model. Information Technology & People, 36(6), 2259-2279. https://doi.org/10.1108/ITP-06-2021-0500
  25. Ikeda, H., Kubo, T., Nishimura, Y., & Izawa, S. (2023). Effects of work-related electronic communication during non-working hours after work from home and office on fatigue, psychomotor vigilance performance and actigraphic sleep: observational study on information technology workers. Occupational and Environmental Medicine, 80(11), 627-634. https://doi.org/10.1136/oemed-2023-108962
  26. Kim, K. H., & Chon, M. G. (2022). When work and life boundaries are blurred: the effect of after-hours work communication through communication technology on employee outcomes. Journal of Communication Management, 26(4), 386-400. https://doi.org/10.1108/JCOM-06-2022-0073
  27. Lanaj, K., Johnson, R. E., & Barnes, C. M. (2014). Beginning the workday yet already depleted? Consequences of late-night smartphone use and sleep. Organizational Behavior and Human Decision Processes, 124(1), 11-23. https://doi.org/10.1016/j.obhdp.2014.01.001
  28. Lee, S., Zhou, Z. E., Xie, J., & Guo, H. (2021). Work-related use of information and communication technologies after hours and employee fatigue: the exacerbating effect of affective commitment. Journal of Managerial Psychology, 36(6), 477-490. https://doi.org/10.1108/JMP-12-2019-0677
  29. Li, J., Chen, H., Wang, L., & Bao, J. (2024). Tit for tat? A study on the relationship between work connectivity behavior after-hours and employees’ time banditry behavior. Frontiers in Psychology, 14, 1322313. https://doi.org/10.3389/fpsyg.2023.1322313
  30. Liao, G., Feng, L., Zheng, X., & Zhou, J. (2024). Buffering or boosting? The dynamic curvilinear relationship between work-related use of information and communication technologies after-hours and wok procrastination. Heliyon, 10(10). https://doi.org/10.1016/j.heliyon.2024.e30565
  31. Liao, Y., Yang, Z., Wang, M., & Kwan, H. K. (2016). Work–family effects of LMX: The moderating role of work–home segmentation preferences. The Leadership Quarterly, 27(4), 671–683. https://doi.org/10.1016/j.leaqua.2016.03.003 Liu, Y., Bai, Q., Yuan, Y., Li, B., Liu, P., Liu, D.,. & Zhao, L. (2024). Impact of work connectivity behavior after-hours on employees’ unethical pro-family behavior. Current Psychology, 43(13), 11785-11803. https://doi.org/10.1007/s12144-023-05291-9
  32. Luna-Arocas, R., Danvila-Del Valle, I., & Lara, F. J. (2020). Talent management and organizational commitment: the partial mediating role of pay satisfaction. Employee Relations: The International Journal, 42(4), 863-881. https://doi.org/10.1108/ER-11-2019-0429
  33. Luthans F., Avolio B. J., Walumbwa F. O., Li W. (2005). The psychological capital of Chinese workers: Exploring the relationship with performance. Management and Organization Review, 1(2), 249–271. https://doi.org/10.1111/j.1740-8784.2005.00011.x
  34. Mahood, Q., Van Eerd, D., & Irvin, E. (2014). Searching for grey literature for systematic reviews: challenges and benefits. Research Synthesis Methods, 5(3), 221-234. https://doi.org/10.1002/jrsm.1106
  35. Meijman, T. F., & Mulder, G. (2013). Psychological aspects of workload. In A handbook of work and organizational psychology (pp. 5-33). Psychology press.
  36. Mellner, C. (2016). After-hours availability expectations, work-related smartphone use during leisure, and psychological detachment: The moderating role of boundary control. International Journal of Workplace Health Management, 9(2), 146-164. https://doi.org/10.1108/IJWHM-07-2015-0050
  37. Munn, Z., Peters, M. D., Stern, C., Tufanaru, C., McArthur, A., & Aromataris, E. (2018). Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Medical Research Methodology, 18, 1-7. https://doi.org/10.1186/s12874-018-0611-x
  38. Murphy, C., Marcus-Quinn, A., & Hourigan, T. (2021). Exploring the ripple effect of ‘always on’digital work culture in secondary education settings. In Handbook for online learning contexts: digital, mobile and open: Policy and practice (pp. 339-353). Springer International Publishing.
  39. Murray, W. C., & Rostis, A. (2007). Who’s running the machine? A theoretical exploration of work stress and burnout of technologically tethered workers. Journal of Individual Employment Rights, 12(3), 249-263. https://doi.org/10.2190/IE.12.3.f
  40. Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D.,. & Moher, D. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372. https://doi.org/10.1136/bmj.n71
  41. Park, Y., Liu, Y., & Headrick, L. (2020). When work is wanted after hours: Testing weekly stress of information communication technology demands using boundary theory. Journal of Organizational Behavior, 41(6), 518-534. https://doi.org/10.1002/job.2461
  42. Rau, B. L., and Hyland, M. M. (2002). Role conflict and flexible work arrangements: the effects on applicant attraction. Personnel Psychology 55, 111–136. https://doi.org/10.1111/j.1744-6570.2002.tb00105.x
  43. Reinke, K., Niederkrome, L., & Ohly, S. (2023). Boundary work tactics and their effects on information and communication technology use after hours and recovery: Taking action when boundaries are blurring. Journal of Personnel Psychology. https://doi.org/10.1027/1866-5888/a000335
  44. Ren, S., Hu, J., Tang, G., & Chadee, D. (2023). Digital connectivity for work after hours: Its curvilinear relationship with employee job performance. Personnel Psychology, 76(3), 731-757. https://doi.org/10.1111/peps.12497
  45. Richardson K. M., Thompson C. A. (2012). High tech tethers and work-family conflict: A conservation of resources approach. Engineering Management Research, 1(1), 29–43. http://doi.org/10.5539/emr.v1n1p29.
  46. Rosenbloom, T., & Eldror, E. (2017). Perfectionism as a moderator of the association of work connectivity behavior after-hours (WCBA) and burnout. North American Journal of Psychology, 19(2), 461–476. https://psycnet.apa.org/record/2017-24005-013
  47. Schlachter, S., McDowall, A., Cropley, M., & Inceoglu, I. (2018). Voluntary work‐related technology use during non‐work time: A narrative synthesis of empirical research and research agenda. International Journal of Management Reviews, 20(4), 825-846. https://doi.org/10.1111/ijmr.12165
  48. Shi, Y., Zhang, H., Xie, J., & Ma, H. (2021). Work-related use of information and communication technologies after hours and focus on opportunities: The moderating role of work-family centrality. Current Psychology, 40, 639-646. https://doi.org/10.1007/s12144-018-9979-3
  49. Skinner, N., & Pocock, B. (2008). Work—life conflict: Is work time or work overload more important?. Asia Pacific Journal of Human Resources, 46(3), 303-315.
  50. Şen, H. (2024). Innovation and Human Resources Management in the Health Sector: Systematic Review Study. Yönetim Bilimleri Dergisi, 22(53), 1038-1059. https://doi.org/10.35408/comuybd.1409833
  51. Şahin, S., Çankır, B., & Arslan, B. S. (2021). Effect of implicit voice theories on employee constructive voice and defensive silence: A study in education and health sector. Organizacija, 54(3), 210-226. https://sciendo.com/article/10.2478/orga-2021-0014
  52. Sonnentag, S., & Fritz, C. (2015). Recovery from job stress: The stressor‐detachment model as an integrative framework. Journal of Organizational Behavior, 36(S1), S72-S103. https://doi.org/10.1002/job.1924
  53. Tao, A., Xu, Q., Zhou, C., Wang, W., & Yu, F. (2023). Work Connectivity Behavior After-Hours and Turnover Intention: A Configuration Perspective. SAGE Open, 13(4), 21582440231218847. https://doi.org/10.1177/21582440231218847
  54. van Zoonen, W., Sivunen, A., & Rice, R. E. (2020). Boundary communication: How smartphone use after hours is associated with work-life conflict and organizational identification. Journal of Applied Communication Research, 48(3), 372-392. https://doi.org/10.1080/00909882.2020.1755050
  55. Wajcman, J. and Rose, E. (2011). Constant Connectivity: Rethinking Interruptions at Work, Organization Studies, 32(7), 941–961. https://doi.org/10.1177/0170840611410829
  56. Wang, H., Liu, P., Zhao, X., Li, A., & Xiao, C. (2022). Work-related use of information and communication technologies after hours (W_ICTs) and work-family conflict: a moderated mediation model. Sage Open, 12(3), 21582440221120169. https://doi.org/10.1177/21582440221120169
  57. Wang, F., Zhang, Z., & Shi, W. (2023a). Relationship between daily work connectivity behavior after hours and work–leisure conflict: Role of psychological detachment and segmentation preference. PsyCh Journal, 12(2), 250-262. https://doi.org/10.1002/pchj.625
  58. Wang, F., Zhang, Z., & Shi, W. (2023b). Effects of segmentation supply and segmentation preference on work connectivity behaviour after hours: a person–environment fit perspective. Current Psychology, 42(32), 28146-28159. https://doi.org/10.1007/s12144-022-03899-x
  59. Wang, R., Li, Z., Bu, C., & Zhu, W. (2023c). Work connectivity behavior after-hours spills over to cyberloafing: The roles of motivation and workaholism. Journal of Managerial Psychology, 38(8), 597-610. https://doi.org/10.1108/JMP-11-2022-0602
  60. Weinberger, M. (2022). What is metaverse?—a definition based on qualitative meta-synthesis. Future Internet, 14(11), 310. https://doi.org/10.3390/fi14110310
  61. Xie, J., Ma, H., Zhou, Z. E., & Tang, H. (2018). Work-related use of information and communication technologies after hours (W_ICTs) and emotional exhaustion: A mediated moderation model. Computers in Human Behavior, 79, 94-104. https://doi.org/10.1016/j.chb.2017.10.023
  62. Xu, C., Yao, Z., & Xiong, Z. (2023). The impact of work-related use of information and communication technologies after hours on time theft. Journal of Business Ethics, 187(1), 185-198. https://doi.org/10.1007/s10551-022-05167-1
  63. Yang, N., Chen, C. C., Choi, J., & Zou, Y. (2000). Sources of work‐family conflict: A Sino‐US comparison of the effects of work and family demands. Academy of Management Journal, 43(1), 113-123. https://doi.org/10.2307/1556390
  64. Yang, Y., Yan, R., & Meng, Y. (2022). Can’t disconnect even after-hours: how work connectivity behavior after-hours affects employees’ thriving at work and family. Frontiers in Psychology, 13, 865776. https://doi.org/10.3389/fpsyg.2022.865776
  65. Yang, Y., Yan, R., Li, X., Meng, Y., & Xie, G. (2023). Different results from varied angles: The positive ımpact of work connectivity behavior after-hours on work engagement. Behavioral Sciences, 13(12), 971. https://doi.org/10.3390/bs13120971
  66. Yue, C. A. (2022). The paradox of using public social media for work: The influence of after-hours work communication on employee outcomes. Journal of Business Research, 149, 748-759. https://doi.org/10.3389/fpsyg.2022.865776
  67. Yue, C. A. (2023). Exploring employees’ after-hour work communication on public social media: Antecedents and outcomes. Social Science Computer Review, 41(3), 827-847. https://doi.org/10.1177/08944393211055322
  68. Zhang, L., Tekleab, A. G., Piszczek, M., & Qiu, Y. (2023). Does after-hours work-related information and communication technology use promote work engagement? A preliminary daily dairy study. Journal of Business Research, 157, 113551. https://doi.org/10.1016/j.jbusres.2023.113876
  69. Zhu, F., Gao, Y., & Chen, X. (2024). Freedom or bondage? The double-edged sword effect of work connectivity behavior after-hours on employee occupational mental health. Chinese Management Studies, 18(1), 265-285. https://doi.org/10.1108/CMS-01-2022-0008
  70. Liao, Y., Yang, Z., Wang, M., & Kwan, H. K. (2016). Work–family effects of LMX: The moderating role of work–home segmentation preferences. The Leadership Quarterly, 27(4), 671–683. https://doi.org/10.1016/j.leaqua.2016.03.003 Liu, Y., Bai, Q., Yuan, Y., Li, B., Liu, P., Liu, D.,. & Zhao, L. (2024). Impact of work connectivity behavior after-hours on employees’ unethical pro-family behavior. Current Psychology, 43(13), 11785-11803. https://doi.org/10.1007/s12144-023-05291-9
  71. Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D.,. & Moher, D. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372. https://doi.org/10.1136/bmj.n71