Are open educational resources (OER) and practices (OEP) effective in improving learning achievement? A meta-analysis and research synthesis

Table 3 Meta-regression results for the learning achievement of response from subject

Model	Coefficient	Standard Error	95% lower	95% upper	Z-value	Two-sided p-value
Intercept	− 0.04	0.11	− 0.26	0.18	− 0.33	0.74	Q^b = 17.15, df = 9, p = 0.05*
Subject^a
1 = Business	0.24	0.26	− 0.28	0.75	0.90	0.37
2 = Chemistry	0.06	0.27	− 0.47	0.59	0.21	0.83
3 = Computer science	− 0.40	0.29	− 0.97	0.16	− 1.40	0.16
4 = History	1.14	0.33	0.49	1.78	3.46	0.001**
5 = Mathematics	0.02	0.17	− 0.31	0.36	0.14	0.89
6 = Physics	0.18	0.23	− 0.27	0.63	0.79	0.43
7 = Politics	− 0.02	0.28	− 0.57	0.53	− 0.08	0.94
8 = Sociology	0.12	0.39	− 0.64	0.87	0.30	0.76
9 = Varied	0.16	0.15	− 0.14	0.46	1.06	0.29