Comparison 7. Patient satisfaction.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
7.1 Difficulty levels defined by original studies	6	423	Std. Mean Difference (IV, Random, 95% CI)	0.37 [‐0.03, 0.77]
7.1.1 Difficult	5	333	Std. Mean Difference (IV, Random, 95% CI)	0.49 [0.07, 0.92]
7.1.2 No restriction by intravenous access difficulty level	1	90	Std. Mean Difference (IV, Random, 95% CI)	‐0.19 [‐0.60, 0.23]
7.2 Difficulty levels defined by the success rate with the landmark method	6	423	Std. Mean Difference (IV, Random, 95% CI)	0.37 [‐0.03, 0.77]
7.2.1 Difficult	4	286	Std. Mean Difference (IV, Random, 95% CI)	0.52 [‐0.01, 1.05]
7.2.2 Moderate	2	137	Std. Mean Difference (IV, Random, 95% CI)	0.08 [‐0.51, 0.66]