Levels of CDS relating to error prevention and the associated impact on prescriber workflow
| Level of CDS | Description | Impact on workflow | |
| 5 | Restricted | The prescriber is prevented from proceeding with the prescription with a hard-stop alert. | Interruptive |
| 4 | Permitted | An alert appears where a reason needs to be given by the prescriber to over-ride it in order to progress. | Interruptive |
| 3 | Guided | Elements of the prescription order are auto-populated for the prescriber (eg, dose, frequency, route). | Interruptive/ passive* |
| 2 | Alert | An alert appears, but the prescriber does not need to over-ride this with adding a reason in order to progress. | Passive |
| 1 | None | No CDS appears at the point of prescribing. | None |
*Passive if the guided decision support is accepted, or interruptive if it is over-ridden.
CDS, clinical decision support.