Table 3

Meta-regression based on questionnaires and quality assessment tools (NOS)

Subgroups	Type of questionnaires	Number of studies	Prevalence of anxiety	Lower	Upper	I²
Questionnaires	GAD-7	6	0.3564	0.2822	0.3972	98.00%
	BAI	9	0.3193	0.2531	0.3798	94.90%
	HADS	14	0.2513	0.2299	0.3334	98.90%
	SAS	4	0.2772	0.2314	0.3951	98.70%
	HAM-A	6	0.3695	0.3056	0.4382	96.50%
	DASS-21	7	0.4264	0.2725	0.5338	70.60%
Quality assessment tool (NOS)	High	27	0.308	0.257	0.366	99.44%
Quality assessment tool (NOS)	Medium	19	0.216	0.189	0.293	95.87%

BAI, Beck Anxiety Inventory; DASS-21, 21-Item Depression, Anxiety and Stress Scale; GAD-7, General Anxiety Disorder-7; HADS, Hospital Anxiety and Depression Scale; HAM-A, Hamilton Anxiety Rating Scale; NOS, Newcastle–Ottawa Scale; SAS, Sedation Agitation Scale.