Characteristics of included studies (n = 20)
| No | |
| Type of healthcare provider | |
| General practitioners | 13 |
| Medical specialists | 3 |
| Other healthcare providers | 4 |
| Type of guideline | |
| National | 15 |
| Regional/local | 5 |
| Subject of study | |
| Preventive care | 5 |
| Diagnosis and treatment | 12 |
| Prevention/diagnosis and treatment | 3 |
| Study design | |
| Cluster RCT | 9 |
| Controlled before and after study | 5 |
| Interrupted time series design | 1 |
| Uncontrolled before and after study | 5 |
| Implementation strategy* | |
| Single | 3 |
| Distribution of educational materials | 2 |
| Outreach visits vs audit and feedback | 1 |
| Multifaceted | 17 |
| Distribution of educational materials | 11 |
| Educational meetings | 14 |
| Local consensus processes | 3 |
| Educational outreach visits | 4 |
| Audit and feedback | 11 |
| Reminders | 5 |
| Marketing | 3 |
| Financial intervention | 1 |
| Type of effect measured | |
| Process and/or structure of care | 19 |
| Patient health outcomes | 9 |
RCT, randomised controlled trial.
*Interventions used as part of a single or multifaceted strategy were classified according to the Effective Practice and Organization of Care Group taxonomy of interventions.23