Table 1. Review characteristics and reliability criteria.

						Reliability criteria
First author, year	Number of included studiesa	Total number of participants across all included studiesb	Participant populations	Years of publication of included studiesc	Number (%) studies measuring problematic gamingd	(1) Defined eligibility criteria?	(2) Conducted a comprehensive search?	(3) Assessed of risk of bias?	(4) Used appropriate methods to combine results? e	(5) Conclusions about depression and anxiety supported by evidence?	(6) Specified which outcomes would be included in the synthesis?
Sugaya 2019 [27]	51	Unclear	Age 0–28	Until 2018	25(56.8)	Yes	Yes	No	Yes	No	No
González-Bueso 2018 [28]	24	53,889	Any	2011–2017	17 (70.8)	Yes	Yes	No	Unclear	No	No
Mihara 2017 [29]	47	127,749	Any	Until 2016	44 (93.6)	Yes	No	No	Yes	No	No
Männikkö 2017 [30]	50	129,430	>12.5 years	2005–2016	41 (82.0)	Yes	Yes	Yes	No	No	No
King 2013 [31]	63	58,415	Any	2000–2012	39 (61.9)	Yes	Yes	No	Yes	No	No
Kuss 2012 [32]	58	Unclear	Any	2000–2010	33 (56.9)	Yes	No	No	Yes	No	No
Kuss 2012 [33]	30	72,825	Children	2000–2011	20 (66.7)	Yes	Yes	No	Yes	No	No

Notes:

^(a) The number of included studies for a review is taken from the PRISMA flow diagram (where possible) or from reports in the text or tables of each review.

^(b)The number of participants was taken directly from the text where possible or calculated from other information that was reported in the review.

^(c) If no years were given, the end year was listed as one year prior to the year of publication.

^(d) Proportion of studies measuring problematic gaming was assessed out of all studies mentioned in the review. This did not always match the number of studies that were said to be included in the review in the abstract, methods, or results.

^(e) most reviews did not combine results quantitatively.