Pick 3–5 core databases for health research, then add field-specific sources based on your question, study designs, and region to build a complete search.
Database choice shapes what you find, what you miss, and how long screening takes. Pick too few and you risk gaps. Pick too many and noise buries the signal. The sweet spot is a focused set that matches your topic, methods, and audience. This guide lays out a simple path you can reuse on any project.
Choosing Databases For Systematic Review In Health Research: Practical Steps
Start With A Clear Question
Write your question with a structure such as PICO or PEO. List the main concepts and acceptable variants. Note the study designs you need, from randomized trials to qualitative work. Add any limits on language, setting, participant age, and publication years. This one page becomes your map for the search plan.
Shortlist Core Databases
Most health topics benefit from a blend of biomedical, trials, and subject-focused sources. The set below covers the usual starting point for clinical and public health reviews. You can remove or add items later after a quick scoping check.
| Database | Strength In SRs | When It’s A Must |
|---|---|---|
| MEDLINE (via PubMed or Ovid) | Gold-standard biomedical coverage; MeSH terms; strong indexing | Any clinical, epidemiology, or health services question |
| Embase | Broader drug and device coverage; Emtree terms; more conference abstracts | Pharmacology, devices, or when sensitivity matters |
| Cochrane CENTRAL | Trials register built from multiple sources | Any review of randomized trials |
| CINAHL | Nursing and allied health journals; subject headings tailored to practice | Nursing, rehabilitation, allied health interventions |
| PsycInfo | Psychology and mental health focus | Mental health, behavior change, sleep, pain, substance use |
| Web Of Science or Scopus | Citation tracking and cross-disciplinary reach | Methodological breadth, forward citation chasing |
Run A Quick Scoping Pass
Test two or three hallmark articles you already trust. Where are they indexed? If your set fails to retrieve them with reasonable terms, adjust the mix before building the full strategy. A five-minute scoping pass often saves hours later.
Core Biomedical Databases: What Each Adds
MEDLINE
MEDLINE remains the backbone for health topics. It uses Medical Subject Headings (MeSH), phrase mapping, and rich publication types. Whether you search via PubMed or a vendor platform, learn how the interface handles subject headings, explosion, field tags, and filters. Keep filters gentle at first, especially for study design, so you do not trim away eligible records.
Embase
Embase brings wider coverage for drugs, devices, and European journals, plus conference abstracts and its own Emtree vocabulary. Many MEDLINE journals are included, yet the indexing differs. Running both often yields extra relevant records and better recall on drug names and device terms. Plan for deduplication across platforms after export.
Cochrane CENTRAL
CENTRAL aggregates trials from multiple sources, including registers and handsearching, and is quick to screen. For questions centering on randomized trials, CENTRAL is low effort with a high return, and it pairs well with MEDLINE and Embase.
CINAHL And PsycInfo
CINAHL shines for nursing, rehabilitation, and health education. PsycInfo anchors mental health, behavior change, cognition, and sleep. When your PICO leans into care delivery, patient experience, or psychological outcomes, these two add depth you won’t get elsewhere.
Match Databases To Your Question
Interventions And Trials
For drug, device, or procedure questions, MEDLINE, Embase, and CENTRAL form the core. Add topic sources where practice lives: CINAHL for nursing-led care, PsycInfo for mental health components, or specialty indexes such as SportDiscus for exercise topics.
Diagnostics And Screening
Diagnostic accuracy work benefits from MEDLINE and Embase, with careful use of subject headings for sensitivity and specificity, predictive values, and index tests. Add CENTRAL for trial-like evaluations and consider specialty sources tied to the body system, such as IEEE Xplore for device algorithms when relevant.
Public Health And Policy
Questions on prevention, services, or policy require a wider lens. Keep MEDLINE and Embase, then add Scopus or Web of Science for policy and social science spillover. Global Health and WHO sources help when the setting spans multiple regions.
Qualitative And Mixed Methods
When experiences or implementation matter, CINAHL and PsycInfo help locate qualitative studies and mixed-methods work. Use text-word variants for interviews, focus groups, and thematic analysis, plus headings for qualitative research where available.
Use Standards And Report Clearly
Two resources set the bar for transparent searching. The Cochrane Handbook technical supplement explains how to plan sources, design strategies, record platform details, and save full search strings. The PRISMA-S checklist lists the items to report so others can reproduce your process without guesswork.
Balance Sensitivity And Precision
Work Back From Your Screening Load
Set a target for how many records you can screen given team size and time. If your first pilot pulls far too many, tighten fields, add proximity operators, or restrict to title/abstract for the broadest concepts while keeping subject headings expanded. If yield seems thin, broaden synonyms and remove narrow limits before adding new databases.
Know Where Overlap Happens
Embase includes many MEDLINE records but indexes them with different terms, which changes retrieval. That’s why running both is still common. CENTRAL also overlaps with MEDLINE and Embase but can surface trials missed by text-word searching. Deduplicate after export and keep a log of how many records each source contributed.
Build Search Strategies That Travel
Use Both Headings And Text Words
Combine controlled vocabulary with free-text synonyms for each concept. Map brand and generic names for drugs, model names for devices, lay terms for conditions, and common abbreviations. Keep the structure modular so you can translate it across platforms with minor tweaks.
Record Platform Details
Note the interface (PubMed, Ovid, EBSCO, Elsevier), the exact years searched, and any human limits used. Save the full strategy and the export settings. These details matter for reproducibility and let peers understand differences in yield across teams.
Sample Database Menus By Review Type
Use the matrix below as a starting menu. Tune based on scope, language, and access.
| Review Type | Core Databases | Extras To Consider |
|---|---|---|
| Drug Or Device RCTs | MEDLINE; Embase; CENTRAL | ClinicalTrials.gov; WHO ICTRP; Web Of Science |
| Nursing Interventions | MEDLINE; CINAHL; CENTRAL | Embase; PsycInfo |
| Mental Health Treatments | MEDLINE; PsycInfo; Embase | CENTRAL; Web Of Science |
| Public Health Programs | MEDLINE; Embase; Scopus | Global Health; government and NGO sites |
| Diagnostics | MEDLINE; Embase | CENTRAL; specialty indexes by organ system |
| Qualitative Evidence | CINAHL; PsycInfo; MEDLINE | Scopus; Social Science indexes |
Grey Sources And Registers
Trial Registers
For unmet outcomes or harms, trial registers add protocols and results that never reach journals. ClinicalTrials.gov and the WHO ICTRP are fast to scan and help reduce publication bias. When trials drive your review, always add at least one register.
Guidelines And Reports
Health technology reports, guideline banks, and agency sites can reveal data not present in journals. Use them as supplements, not substitutes for database searching, and capture the search dates and terms just as you do elsewhere.
Plan Deduplication And Data Flow
Keep A Transparent Count
Export each database to a reference manager or a screening tool, mark the source, and deduplicate in a consistent order. Store raw exports so you can recheck counts. Keep a running tally of imported, deduplicated, screened, and included records by source to make your PRISMA flow quick to build.
Note Interface Quirks
Some platforms cap export sizes, collapse author names, or strip abstracts. Test early and adjust. If a vendor limits batch size, schedule multiple exports and name files with clear date-time stamps.
Quality Checks Before You Lock The Plan
Run A Known-Item Test
List ten must-have studies across years and designs. Confirm your strategy retrieves them in each core database. If one keeps missing a must-have, review your headings, synonyms, and field tags, or add a targeted extra database that clearly fits the gap.
Pilot Screening With The Team
Screen a small random slice to judge noise. Tweak only one element at a time and note the change in yield. Stop tuning once you hit an acceptable balance between missed hits and screening load.
Write It Up With Reproducibility In Mind
Document Choices, Not Just Results
State why each database was chosen, the platform used, years covered, and any language or study-type limits. Include the full strategies in an appendix or repository. Align write-up items with PRISMA-S so peers can repeat the process without guesswork.
Quick Checklist You Can Reuse
- Define the question and concepts with PICO or PEO.
- Pick 3–5 core databases that match the topic.
- Add subject databases tied to care setting or method.
- Draft modular strategies with headings and text words.
- Scoping pass with known items; adjust the mix.
- Record platforms, dates, and export settings.
- Search trial registers and note terms and dates.
- Export, deduplicate, and log counts by source.
- Pilot screening; tune for manageable precision.
- Report with PRISMA-S items and share full strings.
Final Checks Before You Search
Ask two quick questions: Does your set reflect where your topic lives, and can your team screen what it will produce? If yes, you’re ready to run the full strategies, export clean sets, and move into screening with confidence.