. 2020 Aug 21;8:481. doi: 10.3389/fped.2020.00481
Copyright © 2020 Borysewicz-Sańczyk, Sawicka, Wawrusiewicz-Kurylonek, Głowińska-Olszewska, Kadłubiska, Gościk, Szadkowska, Łosiewicz, Młynarski, Kretowski and Bossowski.
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Figure 1.
The study selection process.