Ultrasound guidance showed no clear difference in overall success rate compared with anatomical landmarks (moderate certainty).
It is very uncertain whether [Dorsalis pedis] B‐mode ultrasound guidance changes overall success rate compared with palpation and landmarks (very low certainty).
[Radial] B‐mode ultrasound guidance may leads to higher overall success rate compared with palpation and landmarks (low certainty).
[Radial] B‐mode ultrasound showed no clear difference in overall success rate compared with doppler assistance (low certainty).
It is very uncertain whether [Axillary] B‐mode ultrasound guidance changes overall success rate compared with palpation and landmarks (very low certainty).
It is very uncertain whether [Radial] B‐mode ultrasound changes overall success rate compared with near‐infrared laser guidance (very low certainty).
[Radial] B‐mode ultrasound showed no clear difference in overall success rate compared with modified B‐mode ultrasound (low certainty).
[Radial] In‐plane B‐mode ultrasound showed no clear difference in overall success rate compared with out‐of‐plane B‐mode ultrasound (low certainty).
[Radial] Doppler assistance showed no clear difference in overall success rate compared with palpation and landmarks (low certainty).
It is very uncertain whether [Radial] Dynamic out‐of‐plane B‐mode ultrasound changes overall success rate compared with static out‐of‐plane B‐mode ultrasound (very low certainty).
[Radial] Oblique‐axis in‐plane B‐mode ultrasound may leads to higher overall success rate compared with long‐axis in‐plane B‐mode ultrasound (low certainty).
Ultrasound or Doppler guidance showed no clear difference in overall success rate compared with anatomical landmark (low certainty).