Portal Home
Tips for Using:
SPH Portal
Using EBM Filters in Ovid MEDLINE
A filter or hedge is a standardized search strategy that is designed to be used in conjunction with a subject search to retrieve valid studies from the primary medical literature. All of the below filters can be used in the Medline/OVID search system. To utilize these filters combine the appropriate filter with your subject search using the Boolean operator AND to obtain relevant articles with high validity.
Therapy Questions
Recommended Subject Headings:
| Research | Clinical Protocols | Feasibility Studies |
| Pilot Projects | Reproducibility of Results | Research Design |
| Double-blind Method | Randomized Controlled Trials | Patient Selection |
| Random Allocation | Sample Size | Comparative Study |
| Placebos | Clinical Trials |
Example:
Atrial Fibrillation AND Warfarin AND Randomized Controlled Trials
Recommended Subheadings (attach to subject):
| Drug therapy (dt) | Example: Lyme Disease/dt |
| Therapeutic use (tu) | Example: Aspirin/tu |
Please note that for therapy questions it is also useful to use the following recommended publication types, which can be applied as limits in the "more limits" section.
| Multi-center Study | Meta-analysis | Clinical Trials |
| Clinical Trials, Phase IV | Controlled Clinical Trials | Randomized Controlled Trials |
Diagnosis Questions
Recommended Subject Headings:
| Sensitivity and Specificity | False Negative Reactions | False Positive Reactions |
| Pilot Projects | Reproducibility of Results | Research Design |
| Predictive Value of Tests | Differential Diagnosis | Likelihood Functions |
Example: International Normalized Ratio AND Sensitivity and Specificity
Recommended Subheadings (attach to subject):
| Diagnostic use (du) | Example: Sulfur/du |
| Diagnosis (di) | Example: Alzheimer's Disease/di |
Prognosis Questions
Recommended Subject Headings:
| Cohort Studies | Longitudinal Studies | Prospective Studies |
| Survival Analysis | Morbidity | Death |
| Follow-up Studies | Prognosis | Treatment Outcome |
| Infant Mortality | Maternal Mortality | Cause of Death |
| Medical Futility | Treatment Failure | Mortality |
Example: Diabetes Mellitus AND Survival Rate
Recommended Subheadings (attach to subject):
| Mortality (mo) | Example: Diabetes Mellitus/mo |
| Epidemiology (ep) | Example: Lyme Disease/ep |
Etiology Questions
Recommended Subject Headings:
| Cross-sectional Studies | Odds Ratio | Risk Factors |
| Risk | Analytic Studies | Case-control Studies |
| Retrospective Studies | Cohort Studies | Longitudinal Studies |
| Prospective Studies | Follow-up Studies | | >
Example:Diabetes Mellitus AND Survival Rate
Recommended Subheadings (attach to subject):
| Etiology (et) | Example: Lung Neoplasms/et |
| Chemically induced (ci) | Example: Cirrhosis/ci |
