Medication reconciliation showed no clear difference in medication errors ( compared with no medication reconciliation (low certainty).
Medication reconciliation: pharmacist may leads to lower medication errors ( compared with other professionals (low certainty).
It is very uncertain whether medication reconciliation by trained pharmacist technician changes medication errors ( compared with pharmacist (very low certainty).
CPOE/CDSS showed no clear difference in medication errors ( compared with control/paper‐based (moderate certainty).
Improved CPOE/CDSS probably leads to lower medication errors ( compared with standard CPOE/CDSS (moderate certainty).
Barcoding may leads to lower medication errors ( compared with no barcoding (low certainty).
Organisational changes: reduced showed no clear difference in medication errors ( compared with unreduced working hours (low certainty).
Feedback on prescribing errors may leads to lower medication errors ( compared with no feedback (low certainty).
It is very uncertain whether feedback on prescribing errors changes medication errors ( compared with education on prescribing errors (very low certainty).
It is very uncertain whether education changes medication errors ( compared with no education on prescribing or administration (very low certainty).
Dispensing system may leads to lower medication errors (surgical wards) ( compared with control (low certainty).
It is very uncertain whether dispensing system changes medication errors (operating rooms) ( compared with control (very low certainty).