Table 2.

Publication bias test results.

Influencing factors	K	N	Fail-safe N			Egger’s test
			Nfs	Z-value	p-value	Egger’s intercept	SE	p
Education level	37	17,71,854	1,029	56.792	p < 0.001	9.640	6.789	0.164
Higher education participation	12	5,15,979	7,802	98.859	p < 0.001	−28.333	9.456	0.130
Lifelong learning engagement	10	30,299	2,948	46.268	p < 0.001	−7.753	2.844	0.433

*p < 0.05, **p < 0.01, ***p < 0.001. K = number of studies; N = total sample size; Nfs = fail-safe N; SE = standard error; Egger’s intercept = regression-based intercept used in publication bias test.