This study aims to investigate and examine PBL treatment duration predicted as a potential factor moderating heterogeneity of students' MCTS. A meta-analysis by selecting the random effect model was employed to conduct this study. Data analysis used the Q Cochrane test and Z test supported by Comprehensive Meta-Analysis (CMA) software. A literature search found 220 documents, and the final literature selection established 23 documents in journal articles and 4 documents in proceeding articles indexed by Scopus, Google Scholar, or Web of Science and published in the period of 2013 – 2021. The results revealed that the p-value of the Q statistic related to the factor of PBL treatment duration was less than 0,05 (p = 0,535). It indicates that PBL treatment duration is not a significant factor moderating heterogeneity of students' MCTS. It interprets that the gap of students' MCTS level through PBL is not caused by the treatment duration factor. Furthermore, PBL treatment in the period of 3 – 6 months was more effective to enhance students' MCTS than PBL treatment duration was less than 3 months or more than 6 months. For a further similar meta-analysis study, other researchers should investigate and examine other potential factors such as PBL class capacity and students’ demography that are able to moderate heterogeneity of students’ MCTS

Ahdhianto, E., Marsigit, M., Haryanto, H., & Nurfauzi, Y. (2020). Improving fifth-grade students’ mathematical problem-solving and critical thinking skills using problem-based learning. Universal Journal of Educational Research, 8(5), 2012–2021. https://doi.org/10.13189/ujer.2020.080539

Alghadari, F. (2013). Pembelajaran berbasis masalah untuk meningkatkan kemampuan dan disposisi berpikir kritis matematis siswa SMA. Jurnal Penelitian Pendidikan UPI, 13(2), 164–171. https://doi.org/10.17509/jpp.v13i2.3428

Alnita, A., & Arifin, R. R. M. (2017). Model pembelajaran berbasis masalah terhadap peningkatan kemampuan berpikir kritis matematis siswa kelas V sekolah dasar. Antologi UPI, 5(1), 178–186. Retrieved from https://media.neliti.com/media/publications/240703-problem-based-learning-model-to-increase-35cff592.pdf

Apriliana, L. P., Handayani, I., & Awalludin, S. A. (2019). The effect of problem-centered learning on student's mathematical critical thinking. Journal of Research and Advances in Mathematics Education, 4(2), 124–133. https://doi.org/10.23917/jramathedu.v4i2.8386

Arifin, S., Setyosari, P., Sa’dijah, C., & Kuswandi, D. (2020). The effect of problem-based learning by cognitive style on critical thinking skills and students’ retention. Journal of Technology and Science Education, 10(2), 271–281. https://doi.org/https://doi.org/10.3926/jotse.790

Arviana, R., Irwan, & Dewi, M. P. (2018). Problem-based learning in mathematics education and its effect on student's critical thinking. Advanced Science Letters, 24(1), 211–213. https://doi.org/10.1166/asl.2018.11962

Ayuni, F. A. P., Syaiful, & Siburian, J. (2021). Kemampuan berpikir kritis siswa pada pembelajaran online inquiry dan problem-based learning ditinjau dari kemampuan awal. Jurnal Cendekia: Jurnal Pendidikan Matematika, 5(1), 274–285. https://doi.org/https://doi.org/10.31004/cendekia.v5i1.450

Bellamy, C. (2007). Online democratic deliberation in a time of information abundance. Fast Capitalism, 2(2), 121–126. https://doi.org/10.32855/fcapital.200701.011

Borenstein, M., Hedges, L. V., Higgins, J. P. T., & Rothstein, H. R. (2009). Introduction to meta-analysis. John Willey and Son Ltd. https://doi.org/10.1007/978-3-319-14908-0_2

Buana, I. M. E. T., Astawan, I. G., & Japa, I. G. N. (2020). Improving students' creative thinking skills in mathematics through PBL based on Catur Pramana by controlling students' numeric skills. Jurnal Ilmiah Sekolah Dasar, 4(3), 440–448. https://doi.org/10.23887/jisd.v4i3.25984

Chaffee, J. (2017). Thinking critically (12th ed.). Cengage Learning.

Cohen, L., Manion, L., & Morrison, K. (2018). Research Methods in Education (8th ed.). Routledge Taylor & Francis Group.

Cooper, H. M., Patall, E. A., & Lindsay, J. J. (2013). Research synthesis and meta-analysis. In L. Bickman & D. J. Rog (Eds.), The SAGE handbook of applied social research methods (pp. 344–370). Sage Publications Inc. https://doi.org/https://dx.doi.org/10.4135/9781483348858

Cumming, G. (2012). Understanding the new statistics: Effect sizes, confidence intervals, and meta-analysis. Routledge Taylor & Francis Group. https://doi.org/10.1111/j.1751-5823.2012.00187_26.x

Dahliana, Marhami, & Mursalin. (2019). Improving students ' mathematical critical thinking abilities through the problem-solving method on the sequences and series course. International Journal for Educational and Vocational Studies, 1(7), 813–816. https://doi.org/10.29103/ijevs.v1i7.2571

Darhim, Prabawanto, S., & Susilo, B. E. (2020). The effect of problem-based learning and mathematical problem posing in improving student’s critical thinking skills. International Journal of Instruction, 13(4), 103–116. https://doi.org/10.29333/iji.2020.1347a

Duval, S., & Tweedie, R. (2000). Trim and fill: A simple funnel-plot-based method of testing and adjusting for publication bias in meta-analysis. Biometrics, 56(June), 455–463. https://doi.org/10.1111/J.0006-341X.2000.00455.X

Epafras, L. C., Djalong, F. A., & Kaunang, H. P. (2019). Beyond signal and noise: Academics go hoax and hoaxtivism. Kawistara, 8(3), 213–309. https://doi.org/10.22146/kawistara.34646

Gunur, B., Ramda, A. H., & Makur, A. P. (2019). Pengaruh pendekatan problem-based learning berbantuan masalah open-ended terhadap kemampuan berpikir kritis ditinjau dari sikap matematis siswa. JOHME: Journal of Holistic Mathematics Education, 3(1), 1–15. https://ojs.uph.edu/index.php/JOHME/article/view/1912

Haerani, I., Winarti, W., & Muftianti, A. (2019). Meningkatkan kemampuan berpikir kritis siswa Sekolah Dasar kelas IV dalam mata pelajaran matematika melalui model problem based learning. COLLASE (Creative of Learning Students Elementary Education), 2(1), 26–32. Retrieved from https://www.journal.ikipsiliwangi.ac.id/index.php/collase/article/viewFile/3085/805

Hanum, L., Istikomah, D. A., & Jana, P. (2019). Perbandingan keefektifan model pembelajaran problem-based learning (PBL) dan discovery learning (DL) ditinjau dari kemampuan pemecahan masalah. EduMa, 8(1), 67 - 74. http://dx.doi.org/10.24235/eduma.v8i1.3203

Hamid, M. M., & Lambertus. (2014). Efektivitas pembelajaran berbasis masalah terhadap peningkatan kemampuan berpikir kritis matematik siswa kelas VII SMP Negeri 14 Kendari. Jurnal Penelitian Pendidikan Matematika, 2(2), 91–110. http://dx.doi.org/10.36709/jppm.v2i2.3096

Happy, N., & Widjajanti, D. B. (2014). Keefektifan PBL ditinjau dari kemampuan berpikir kritis dan kreatif matematis, serta self-esteem siswa SMP. Jurnal Riset Pendidikan Matematika, 1(1), 48–56. https://doi.org/10.21831/jrpm.v1i1.2663

Hendriana, H., Sumarmo, U., & Rohaeti, E. E. (2013). Kemampuan komunikasi matematis serta kemampuan dan disposisi berpikir kritis matematis. Delta-Pi: Jurnal Matematika Dan Pendidikan Matematika, 2(1), 35–45. http://dx.doi.org/10.33387/dpi.v2i1.97

Higgins, J. P. T., Thompson, S. G., Deeks, J. J., & Altman, D. G. (2003). Measuring inconsistency in meta-analysis. British Medical Journal, 327, 557–560. https://doi.org/10.1007/s10844-006-2974-4

Hmelo-Silver, C. E. (2004). Problem-based learning: What and how do students learn? Educational Psychology Review, 16(3), 235–266. https://doi.org/https://doi.org/10.1023/B:EDPR.0000034022.16470.f3

Hunter, J. E., & Schmidt, F. L. (2004). Methods of meta-analysis: Correcting error and bias in research findings (2nd ed.). Sage Publications Inc. http://library1.nida.ac.th/termpaper6/sd/2554/19755.pdf

Islahuddin, Ilyas, M., Basir, F., & Amini, S. F. (2018). Peningkatan kemampuan berpikir kritis matematika siswa dan habits of mind (striving for accuracy) melalui pembelajaran berbasis masalah. Proximal: Jurnal Penelitian Matematika Dan Pendidikan Matematika, 1(2), 107–116. Retrieved from http://journal.uncp.ac.id/index.php/proximal/article/view/1061

Jumaisyaroh, T., Napitupulu, E. ., & Hasratuddin. (2015). Peningkatan kemampuan berpikir kritis matematis dan kemandirian belajar siswa SMP melalui pembelajaran berbasis masalah. AdMathEdu, 5(1), 87–106. Retrieved from http://journal.uad.ac.id/index.php/AdMathEdu/article/view/4778

Jumaisyaroh, T., Napitupulu, E. E., & Hasratuddin. (2014). Peningkatan kemampuan berpikir Kritis matematis dan kemandirian belajar siswa SMP melalui pembelajaran berbasis masalah. Kreano, Jurnal Matematika Kreatif-Inovatif, 5(2), 157–169. https://doi.org/10.15294/kreano.v5i2.3325

Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gøtzsche, P. C., Ioannidis, J. P. A., Clarke, M., Devereaux, P. J., Kleijnen, J., & Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. In Journal of Clinical Epidemiology (Vol. 62, Issue 10). https://doi.org/10.1016/j.jclinepi.2009.06.006

Lipsey, M. W., & Wilson, D. (2001). Applied social research methods series. Sage Publications Inc. https://psycnet.apa.org/record/2000-16602-000

Littell, J. H., Corcoran, J., & Pillai, V. (2008). Systematic review and meta-analysis. Oxford University Press. https://doi.org/10.1016/j.medine.2017.10.012

Marinda, H., Noer, S. H., & Asnawati, R. (2018). Penerapan model pembelajaran berbasis masalah untuk meningkatkan kemampuan berpikir kritis matematis dan self-confidence siswa. Jurnal Pendidikan Matematika Unila, 6(6), 559–570. http://jurnal.fkip.unila.ac.id/index.php/MTK/article/view/16331

Maulana. (2016). Interaksi PBL-Murder, minat penjurusan, dan kemampuan dasar matematis terhadap pencapaian kemampuan berpikir dan disposisi kritis. Mimbar Sekolah Dasar, 2(1), 1–20. https://doi.org/10.17509/mimbar-sd.v2i1.1318

McHugh, M. L. (2012). Interrater reliability : the kappa statistic. Biochemica Medica, 22(3), 276–282. Retrieved from https://hrcak.srce.hr/89395

Moher, D., Liberati, A., Tetzlaff, J., & Altman, D. G. (2009). Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement. BMJ (Online), 339(7716), 332–336. https://doi.org/10.1136/bmj.b2535

Nugraha, T., & Suparman. (2021a). Heterogeneity of Indonesian primary school students' mathematical critical thinking skills through problem-based learning: A meta-analysis. Al Jabar: Jurnal Pendidikan Matematika, 12(2), 1 - 11. https://doi.org/10.24042/ajpm.v12i2.9645

Nugraha, T., & Suparman. (2021b). Does students' demography cause heterogeneity of students' mathematical critical thinking abilities through problem-based learning? A meta-analysis. Journal of Hunan University Natural Science, 48(8), 1 - 10. Retrieved from http://www.jonuns.com/index.php/journal/article/view/687

Nugraha, T. S., & Mahmudi, A. (2015). Keefektifan pembelajaran berbasis masalah dan problem posing ditinjau dari kemampuan berpikir logis dan kritis. Jurnal Riset Pendidikan Matematika, 2(1), 107–120. https://doi.org/10.21831/jrpm.v2i1.7154

Othman, H., Salleh, B. M., & Sulaiman, A. (2013). 5 ladders of active learning: An innovative learning steps in PBL process. The 4th International Symposium on Problem-Based Learning (IRSPBL) 2013, 245–253. Retrieved from http://eprints.uthm.edu.my/id/eprint/4019/1/5_Ladders_of_Active_Learning.pdf

Prihono, E. W., & Khasanah, F. (2020). Pengaruh model problem-based learning terhadap kemampuan berpikir kritis matematis siswa Kelas VIII SMP. EDU-MAT: Jurnal Pendidikan Matematika, 8(1), 74–87. https://doi.org/10.20527/edumat.v8i1.7078

Ramadhani, R., Bina, N. S., Sihotang, S. F., Narpila, S. D., & Mazaly, M. R. (2020). Students’ critical mathematical thinking abilities through flip-problem-based learning model based on LMS-google classroom. Journal of Physics: Conference Series, 1657(012025), 1–8. https://doi.org/10.1088/1742-6596/1657/1/012025

Ratnawati, D., Handayani, I., & Hadi, W. (2020). Pengaruh model pembelajaran PBL berbantu question card terhadap kemampuan berpikir kritis matematis siswa SMP. Edumatica: Jurnal Pendidikan Matematika, 10(1), 44–51. https://doi.org/10.22437/edumatica.v10i01.7683

Rothstein, H. R., Sutton, A. J., & Borenstein, M. (2005). Publication bias in meta-analysis: Prevention, assessment, and adjustments. John Willey and Son Ltd. https://doi.org/10.1002/0470870168

Sanabria, J. C., & Arámburo-Lizárraga, J. (2017). Enhancing 21st-century skills with AR: Using the gradual immersion method to develop collaborative creativity. Eurasia Journal of Mathematics, Science and Technology Education, 13(2), 487–501. https://doi.org/10.12973/eurasia.2017.00627a

Sanders, S. (2016). Critical and Creative Thinkers in mathematics classrooms. Journal of Student Engagement: Education Matters, 6(1), 19–27. Retrieved from https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1043&context=jseem&httpsredir=1&referer=

Sari, Y., Surya, E., & Asmin. (2020). The increasing of student's mathematics critical thinking ability through problem-based learning. 4th Annual International Seminar on Transformative Education and Educational Leadership, 384(Aisteel), 563–566. https://doi.org/10.2991/aisteel-19.2019.126

Savery, J. R. (2006). Overview of PBL: Definitions and distinctions. Interdisciplinary Journal of Problem-Based Learning, 1(1), 9–20. https://doi.org/https://doi.org/10.7771/1541-5015.1002

Shelby, L. B., & Vaske, J. J. (2008). Understanding meta-analysis: A review of the methodological literature. Leisure Sciences, 30(2), 96–110. https://doi.org/10.1080/01490400701881366

Silber-Varod, V., Eshet-Alkalai, Y., & Geri, N. (2019). Tracing research trends of 21st-century learning skills. British Journal of Educational Technology, 50(6), 1–20. https://doi.org/10.1111/bjet.12753

Sitanggang, S. L., Syahputra, E., & Yus, A. (2020). The effect of problem-based learning model on critical thinking ability student mathematics and adversity student quotient on students SMP Negeri 1 Lubukpakam. Budapest International Research and Critics in Linguistics and Education (BirLE) Journal, 3(4), 1814–1822. https://doi.org/10.33258/birle.v3i4.1374

Sumarmo, U., Hidayat, W., Zukarnaen, R., Hamidah, & Sariningsih, R. (2012). Kemampuan dan disposisi berpikir logis, kritis, dan kreatif matematis. Jurnal Pengajaran Matematika Dan Ilmu Pengetahuan Alam, 17(1), 17. https://doi.org/10.18269/jpmipa.v17i1.228

Sunaryo, Y. (2014). Model pembelajaran berbasis masalah untuk meningkatkan kemampuan berpikir kritis dan kreatif matematis siswa SMA di Kota Tasikmalaya. Jurnal Pendidikan Dan Keguruan, 1(2), 41–51. https://www.neliti.com/publications/209679/

Suparman, Juandi, D., & Tamur, M. (2021a). Problem-based learning for mathematical critical thinking skills: A meta-analysis. Journal of Hunan University (Natural Sciences), 48(2), 133–144. Retrieved from http://www.jonuns.com/index.php/journal/article/view/521

Suparman, Juandi, D., & Tamur, M. (2021b). Review of problem-based learning trends in 2010-2020 : A meta-analysis study of the effect of problem-based learning in enhancing mathematical problem-solving skills of Indonesian students. Journal of Physics: Conference Series, 1722(012103), 1–9. https://doi.org/10.1088/1742-6596/1722/1/012103

Suparman, Juandi, D., & Tamur, M. (2021c). Does problem-based learning enhance students' higher-order thinking skills in mathematics learning? A systematic review and meta-analysis. The 4th International Conference on Big Data and Education, 44–51. https://doi.org/https://doi.org/10.1145/3451400.3451408

Suparman, S., Juandi, D., & Martadiputra, B. A. P. (2021c). Heterogeneity of students' mathematical critical thinking ability reviewed from education levels: A meta-analysis. Paedagogial: Jurnal Penelitian Pendidikan, 24(2), 1 - 18. https://doi.org/10.20961/paedagogia.v24i2.53981

Suparman, Tamur, M., Yunita, Wijaya, T. T., & Syaharuddin. (2021a). Using problem-based learning to enhance mathematical abilities of primary school students : A systematic review and meta-analysis. JTAM (Jurnal Teori Dan Aplikasi Matematika), 5(1), 144–161. https://doi.org/https://doi.org/10.31764/jtam.v5i1.3806

Suparman, Yohannes, & Arifin, N. (2021b). Enhancing mathematical problem-solving skills of Indonesian junior high school students through problem-based learning: a systematic review and meta-analysis. Al-Jabar: Jurnal Pendidikan Matematika, 12(1), 1–16. https://doi.org/10.24042/ajpm.v12i1.8036

Tabun, H. M., Taneo, P. N. L., & Daniel, F. (2020). The ability of student math literation on problem-based learning model. EduMa, 9(1), 34 - 42. http://dx.doi.org/10.24235/eduma.v9i1.6036

Torp, L., & Sage, S. (2002). Problems as possibilities: Problem-based learning for K–16 education (2nd ed.). Association for Supervision and Curriculum Development. Retrieved from http://www.ascd.org

Tunjungsari, A. R., & Tasyanti, T. (2017). Penerapan PBL dengan pendekatan RME berbantuan GeoGebra untuk meningkatkan kemampuan berpikir matematis. Seminar Nasional Matematika X, 556–566. Retrieved from https://journal.unnes.ac.id/sju/index.php/prisma/article/view/21564

Umar, U., Kaharuddin, A., Fauzi, A., Widodo, A., Radiusman, R., & Erfan, M. (2020). A comparative study on critical thinking of mathematical problem-solving using problem-based learning and direct instruction. The 1st Annual Conference on Education and Social Science (ACCESS) 2019, 465, 314–316. https://doi.org/10.2991/assehr.k.200827.079

Vevea, J. L., Zelinsky, N. A. M., & Orwin, R. G. (2019). Evaluating coding decisions. In The handbook of research synthesis and meta-analysis (3rd ed., pp. 174–201). Russel Sage Foundation. https://doi.org/https://doi.org/10.7758/9781610448864

Widada, W., Sarwoedi, S., & Herawaty, D. (2019). Pengaruh problem-based learning berbasis etnomatematika Rejang Lebong terhadap kemampuan berpikir kritis siswa SMA. Annals of Mathematical Modeling, 1(1), 31–34. http://dx.doi.org/10.33292/amm.v1i1.39

Yew, E. H. J., & Goh, K. (2016). Problem-based learning: An overview of its process and impact on learning. Health Professions Education, 2(2), 75–79. https://doi.org/10.1016/j.hpe.2016.01.004

Yolanda, F. (2019). The effect of problem-based learning on mathematical critical thinking skills of junior high school students. Journal of Physics: Conference Series, 1397(012082), 1–8. https://doi.org/10.1088/1742-6596/1397/1/012082

Zetriuslita, Z., & Ariawan, R. (2021). Students' mathematical thinking skills viewed from curiosity through problem-based learning models on integral calculus. Infinity: Journal of Mathematics Education, 10(1), 31–40. https://doi.org/10.22460/infinity.v10i1.p31-40

Zetriuslita, Z., Wahyudin, W., & Jarnawi, J. (2017). Mathematical critical thinking and curiosity attitude in problem-based learning and cognitive conflict strategy: A study in number theory course. International Education Studies, 10(7), 65–78. https://doi.org/10.5539/ies.v10n7p65