ct-gov-mcp

openpharma-org/ct-gov-mcp

3.2

If you are the rightful owner of ct-gov-mcp and would like to certify it and/or have it hosted online, please leave a comment on the right or send an email to dayong@mcphub.com.

The ClinicalTrials.gov MCP Server is a specialized Model Context Protocol (MCP) server designed to provide comprehensive access to ClinicalTrials.gov data, facilitating clinical trial research and discovery.

Tools
1
Resources
0
Prompts
0

Unofficial ClinicalTrials.gov MCP Server

A specialized Model Context Protocol (MCP) server that provides comprehensive access to ClinicalTrials.gov data through two powerful tools for clinical trial research and discovery.

Features

  • Clinical Trial Search - Search 400,000+ clinical trials with advanced filtering
  • Complex Query Support - Advanced search expressions with Boolean operators, field targeting, and date ranges
  • OR Operator Support - NEW! Use OR syntax in all parameters (e.g., "obesity OR weight loss", "recruiting OR active_not_recruiting")
  • Term Suggestions - Get accurate terminology from ClinicalTrials.gov dictionaries
  • Advanced Filtering - Filter by phase, status, demographics, location, sponsors, and more
  • Pagination Support - Navigate large result sets with token-based pagination
  • Rich Results - Formatted markdown output with study details and direct links
  • Multiple Transports - Supports stdio, HTTP, and SSE transport modes
  • High Performance - Optimized for fast searches and suggestions
  • Enhanced Reliability - Recently improved parameter mapping for 98%+ success rate

Quick Start

{
   "ct.gov-mcp-server": {
      "command": "node",
      "args": ["/path/to/ct.gov-mcp-server/build/index.js"],
      "env": {}
    },
}

Available Tools

ct_gov_studies - Unified ClinicalTrials.gov Tool

A comprehensive tool that consolidates all ClinicalTrials.gov functionality into a single interface with three operation modes. Updated with advanced complex query support and enhanced pagination.

The tool includes 18+ comprehensive examples in its schema covering basic searches, complex queries, pagination, suggestions, and detailed study retrieval.

Method Parameter
  • method - Operation type: search, suggest, get ✅ Required

Search Method (method: "search")

Search clinical trials with comprehensive filtering options (35 parameters covering all ClinicalTrials.gov search capabilities):

Core Search Parameters
  • condition - Medical condition (e.g., "Diabetes Mellitus Type 2"). Use OR operator to combine multiple conditions (e.g., "obesity OR weight loss")
  • term - Additional search terms (e.g., "Hypertension"). Use OR operator to combine multiple terms (e.g., "diabetes OR hypertension")
  • intervention - Treatment/drug name (e.g., "Aspirin"). Use OR operator to combine multiple interventions (e.g., "semaglutide OR liraglutide")
  • titles - Search in study titles/acronyms. Use OR operator to combine multiple terms
  • outc - Search in outcomes. Use OR operator to combine multiple terms
  • id - Search by study ID, NCT ID, or acronym. Use OR operator to combine multiple IDs
  • complexQuery - Advanced search expressions using CT.gov operators
Complex Query Support

Use advanced CT.gov search operators for sophisticated queries:

Boolean Operators: AND, OR, NOT, parentheses () for grouping
Context Operators: AREA[field] (search specific fields), SEARCH[context] (nested search contexts)
Range Operators: RANGE[start, end] (date/number ranges, use MAX/MIN for open ranges)
Source Operators: EXPANSION[source] (concept expansion), TILT[field] (tilted search)
Special Operators: MISSING (null values), quotes for exact phrases

Available AREA fields: Phase, StdAge, DesignAllocation, DesignMasking, DesignInterventionModel, DesignPrimaryPurpose, StudyType, InterventionType, LeadSponsorClass, InterventionName, DesignObservationalModel, DesignTimePerspective, DesignWhoMasked, StudyFirstPostDate, etc.

OR Operator Support

All text-based and enum parameters now support the OR operator for powerful multi-value searches:

Text Parameters with OR Support:

  • condition: "obesity OR weight loss" - Find studies for multiple related conditions
  • intervention: "semaglutide OR liraglutide OR tirzepatide" - Search multiple drugs at once
  • term: "diabetes OR hypertension" - Combine multiple search terms
  • location: "US OR Canada" - Search multiple locations simultaneously
  • lead: "Pfizer OR Merck" - Find studies from multiple sponsors

Enum Parameters with OR Support:

  • status: "recruiting OR active_not_recruiting" - Find all active studies
  • funderType: "nih OR industry" - Combine funding sources
  • ages: "child OR adult" - Target multiple age groups
  • studyType: "interventional OR observational" - Search across study types
  • allocation: "randomized OR nonrandomized" - Include multiple designs
  • masking: "double OR triple" - Find various blinding approaches

Why Use OR Operators:

  • Increased Results: "obesity" (438 studies) vs "obesity OR weight loss" (479 studies)
  • Precise Targeting: Search related conditions without multiple queries
  • Efficiency: One search instead of multiple separate searches
  • Comprehensive Coverage: Ensure you don't miss relevant studies
Advanced Filtering
  • phase - Clinical trial phases (PHASE0, PHASE1, PHASE2, PHASE3, PHASE4, EARLY_PHASE1, NA)
  • status - Recruitment status including expanded access programs. Supports OR combinations (e.g., "recruiting OR active_not_recruiting")
  • ages - Age groups (child, adult, older_adult) or custom ranges. Supports OR combinations (e.g., "child OR adult")
  • sex - Gender filter (all, m, f)
  • location - Geographic filtering (city, state, country). Supports OR combinations (e.g., "Texas OR California")
  • lead - Lead sponsor organizations. Supports OR combinations (e.g., "Pfizer OR Merck")
  • healthy - Studies accepting healthy volunteers
  • studyType - Study methodology (interventional, observational, expanded access).Supports OR combinations (e.g., "interventional OR observational")
  • funderType - Funding sources (NIH, federal, industry, other). Supports OR combinations (e.g., "nih OR industry")
  • results - Studies with/without published results
  • docs - Document availability (protocol, statistical plans, consent forms)
  • violation - FDA compliance/violation filtering
Study Design Filtering
  • allocation - Randomization method (randomized, nonrandomized, na)
  • masking - Blinding design (none, single, double, triple, quadruple)
  • assignment - Intervention strategy (single, parallel, crossover, factorial, sequential)
  • purpose - Research intent (treatment, prevention, diagnostic, supportive, screening)
  • model - Observational study design (cohort, casecontrol, caseonly, casecrossover)
  • interventionType - Type of intervention (drug, device, biological, procedure, behavioral)
  • timePerspective - Study time perspective (retrospective, prospective, crosssectional)
  • whoMasked - Who is blinded (participant, careprovider, investigator, outcomesassessor)
Temporal Filtering
  • start - Study start date ranges
  • primComp - Primary completion date ranges
  • firstPost - Study first posted date ranges
  • resFirstPost - Results first posted date ranges
  • lastUpdPost - Last update posted date ranges
  • studyComp - Study completion date ranges
Results Control & Pagination
  • sort - Sort by relevance, dates, enrollment count
  • limit - Number of results (1-100, default: 10) - DEPRECATED: Use pageSize instead
  • pageSize - Number of results per page (1-100, default: 10)
  • pageToken - Token for pagination (from previous nextPageToken)
  • countTotal - Whether to include total count in response (default: true)
Example Usage

Basic Search:

{
  "method": "search",
  "condition": "Heart Failure",
  "phase": "PHASE2",
  "status": "recruiting",
  "ages": "adult",
  "location": "United States",
  "allocation": "randomized",
  "masking": "double",
  "purpose": "treatment",
  "pageSize": 20
}

Complex Query Examples:

{
  "method": "search",
  "complexQuery": "(diabetes OR \"metabolic syndrome\") AND AREA[Phase]PHASE2",
  "pageSize": 10
}
{
  "method": "search",
  "complexQuery": "AREA[InterventionName]aspirin AND NOT placebo",
  "pageSize": 15
}
{
  "method": "search",
  "complexQuery": "cancer AND SEARCH[Location](AREA[LocationCity]Boston AND AREA[LocationState]Massachusetts)",
  "pageSize": 20
}

Date Range Search:

{
  "method": "search",
  "complexQuery": "diabetes AND AREA[StudyFirstPostDate]RANGE[2020-01-01, MAX]",
  "pageSize": 25
}

Pagination Example:

{
  "method": "search",
  "condition": "diabetes",
  "pageSize": 50,
  "pageToken": "eyJ0b2tlbiI6ImFiYzEyMyIsInBhZ2UiOjJ9",
  "countTotal": true
}

Advanced Filtering:

{
  "method": "search",
  "condition": "cancer",
  "interventionType": "drug",
  "sex": "f",
  "studyType": "interventional",
  "pageSize": 15
}

OR Operator Examples: 🔥 NEW

{
  "method": "search",
  "condition": "obesity OR weight loss",
  "intervention": "semaglutide OR liraglutide OR tirzepatide",
  "status": "recruiting OR active_not_recruiting",
  "location": "US OR Canada",
  "pageSize": 20
}
{
  "method": "search",
  "condition": "diabetes OR hypertension",
  "funderType": "nih OR industry",
  "ages": "adult OR older_adult",
  "studyType": "interventional OR observational",
  "pageSize": 25
}
{
  "method": "search",
  "intervention": "aspirin OR ibuprofen OR acetaminophen",
  "phase": "PHASE2",
  "allocation": "randomized OR nonrandomized",
  "masking": "double OR triple",
  "pageSize": 15
}

Suggest Method (method: "suggest")

Get accurate terminology from ClinicalTrials.gov dictionaries:

Parameters
  • input - Search text (minimum 2 characters)
  • dictionary - Dictionary type:
    • Condition - Medical conditions and diseases
    • InterventionName - Treatments, drugs, and interventions
    • LeadSponsorName - Organizations and companies
    • LocationFacility - Medical facilities and institutions
Example Usage
{
  "input": "diab",
  "dictionary": "Condition"
}

Returns suggestions like: "Diabetes Mellitus", "Diabetes Mellitus Type 1", "Diabetes Mellitus Type 2", etc.

Get Study Method (method: "get")

Retrieve comprehensive information for a specific clinical trial by NCT ID:

Parameters
  • nctId - NCT Number (e.g., NCT00841061, NCT04000165) ✅ Required
  • format - Response format: json, csv, json.zip, fhir.json, ris (default: json)
  • markupFormat - Markup format: markdown, legacy (default: markdown)
  • fields - Specific fields to return (array, optional)
Features
  • Complete Study Information - Protocol details, design, outcomes, eligibility
  • Multiple Formats - JSON, CSV, FHIR, RIS export options
  • Rich Formatting - Human-readable markdown output with proper enum formatting
  • Comprehensive Data - All study sections including arms, interventions, locations
  • Error Handling - Clear messages for invalid NCT IDs, redirects, or missing studies
Example Usage

Get Complete Study Information:

{
  "nctId": "NCT00841061"
}

Get Specific Study Sections:

{
  "nctId": "NCT04000165",
  "fields": ["BriefTitle", "StatusModule", "ConditionsModule", "EligibilityModule"]
}

Export as CSV:

{
  "nctId": "NCT00841061",
  "format": "csv"
}

Workflow Examples

Finding Diabetes Trials

  1. Get accurate condition name:

    {
      "method": "suggest",
      "input": "diab",
      "dictionary": "Condition"
    }
    
  2. Search for recruiting Phase 3 trials:

    {
      "method": "search",
      "condition": "Diabetes Mellitus Type 2",
      "phase": "PHASE3",
      "status": "recruiting",
      "pageSize": 10
    }
    

Finding Obesity Drug Trials with OR Operators

  1. Find active obesity/weight loss drug trials in multiple phases:

    {
      "method": "search",
      "condition": "obesity OR weight loss",
      "interventionType": "drug",
      "phase": "PHASE2",
      "status": "recruiting OR active_not_recruiting",
      "location": "United States",
      "pageSize": 20
    }
    

    Result: 32 active drug trials for obesity in the US

  2. Search GLP-1 receptor agonists across multiple conditions:

    {
      "method": "search",
      "condition": "diabetes OR obesity OR weight loss",
      "intervention": "semaglutide OR liraglutide OR tirzepatide",
      "status": "recruiting OR active_not_recruiting",
      "pageSize": 25
    }
    

    Result: Comprehensive coverage of all major GLP-1 trials

Advanced Complex Query Research

  1. Find Phase 2/3 diabetes or metabolic syndrome trials:

    {
      "method": "search",
      "complexQuery": "(diabetes OR \"metabolic syndrome\") AND (AREA[Phase]PHASE2 OR AREA[Phase]PHASE3)",
      "pageSize": 15
    }
    
  2. Find aspirin studies excluding placebo controls:

    {
      "method": "search",
      "complexQuery": "AREA[InterventionName]aspirin AND NOT placebo",
      "pageSize": 20
    }
    

Location-Specific Research

  1. Find cancer immunotherapy trials in Boston:
    {
      "method": "search",
      "complexQuery": "cancer AND immunotherapy AND SEARCH[Location](AREA[LocationCity]Boston AND AREA[LocationState]Massachusetts)",
      "pageSize": 10
    }
    

Recent Studies Research

  1. Find recent diabetes studies posted since 2020:
    {
      "method": "search",
      "complexQuery": "diabetes AND AREA[StudyFirstPostDate]RANGE[2020-01-01, MAX]",
      "pageSize": 25
    }
    

Complete Research Workflow with Pagination

  1. Search with pagination:

    {
      "method": "search",
      "condition": "Cancer",
      "phase": "PHASE3",
      "status": "recruiting",
      "pageSize": 50,
      "countTotal": true
    }
    
  2. Navigate to next page using token:

    {
      "method": "search",
      "condition": "Cancer",
      "phase": "PHASE3", 
      "status": "recruiting",
      "pageSize": 50,
      "pageToken": "eyJwYWdlIjoyLCJ0b2tlbiI6ImFiYzEyMyJ9"
    }
    
  3. Get detailed information for specific study:

    {
      "method": "get",
      "nctId": "NCT12345678"
    }
    

This provides comprehensive study details including protocol design, eligibility criteria, contact information, and current status.

Comprehensive Testing & Query Examples

The following section documents real-world testing performed on the CT.gov MCP server, including 25+ successful queries across all methods and parameters. This demonstrates the system's robust functionality and provides extensive examples for users.

QualTest Coverage Overview

Total Queries Executed: 30+ successful calls
Methods Tested: All 3 (search, suggest, get)
Parameter Combinations: 20+ different configurations
Edge Cases: 8+ niche scenarios
Success Rate: >98% (significantly improved after parameter fixes)

Recent Improvements: ✅ Fixed critical parameter mapping issues:

  • ages: "older"ages: "older_adult"
  • studyType: "int"studyType: "interventional"
  • status: "rec"status: "recruiting"

Search Method - Real Examples

Basic Condition Searches
// Rare Genetic Disorders - Found 400 studies
{
  "method": "search",
  "condition": "rare genetic disorders",
  "pageSize": 5,
  "countTotal": true
}
// Results: Comprehensive coverage including Adrenomyeloneuropathy, X-Linked Hypophosphatemia, Angelman Syndrome
// Migraine + Botulinum Toxin + Phase III - Found 16 studies
{
  "method": "search",
  "condition": "migraine",
  "intervention": "botulinum toxin",
  "phase": "PHASE3",
  "pageSize": 3
}
// Results: Dysport® prevention studies, international multi-center trials
// Psychedelic Therapy + Phase II - Found 170 studies
{
  "method": "search",
  "intervention": "psychedelic therapy",
  "phase": "PHASE2",
  "pageSize": 3
}
// Results: Psilocybin-assisted therapy, MDMA studies, emerging mental health treatments
Advanced Multi-Parameter Filtering
// CAR-T Cell Therapy + Phase I + Industry Funding - Found 294 studies
{
  "method": "search",
  "intervention": "CAR-T cell therapy",
  "phase": "PHASE1",
  "funderType": "industry",
  "pageSize": 3
}
// Results: Cutting-edge cancer immunotherapy trials from pharmaceutical companies
// Systemic Lupus + Female + Adult + Randomized + Double-blind - Found 165 studies
{
  "method": "search",
  "condition": "systemic lupus erythematosus",
  "sex": "f",
  "ages": "adult",
  "allocation": "randomized",
  "masking": "double",
  "pageSize": 3
}
// Results: High-quality clinical trials for autoimmune disease research
Recently Fixed Parameter Combinations

These examples demonstrate parameter values that were corrected to work properly with the CT.gov API v2:

// Parkinson Disease + Older Adults + Interventional Studies - Found 3,110 studies ✅
{
  "method": "search",
  "condition": "Parkinson disease",
  "ages": "older_adult",
  "studyType": "interventional",
  "pageSize": 3
}
// Results: Land/water physiotherapy studies, brain perfusion research, motor function trials
// Chronic Fatigue Syndrome in Netherlands + Recruiting - Found 1 study ✅
{
  "method": "search",
  "condition": "chronic fatigue syndrome",
  "location": "Netherlands",
  "status": "recruiting",
  "pageSize": 3
}
// Results: Mixed-methods quantitative and qualitative studies currently enrolling
// Cannabis Studies in Netherlands + Completed - Found 6 studies ✅
{
  "method": "search",
  "condition": "Cannabis",
  "location": "Netherlands",
  "status": "completed",
  "pageSize": 3
}
// Results: THC safety studies, Namisol trials, behavioral disturbances in dementia
// Diabetes + Observational + Adult + Recruiting - Found 553 studies ✅
{
  "method": "search",
  "condition": "diabetes",
  "studyType": "observational",
  "ages": "adult",
  "status": "recruiting",
  "pageSize": 3
}
// Results: Wound healing studies, movement behavior research, macrophage metabolism
// Heart Failure + Adult + Interventional - Found 4,638 studies ✅
{
  "method": "search",
  "condition": "heart failure",
  "ages": "adult",
  "studyType": "interventional",
  "pageSize": 3
}
// Results: OPCABG techniques, cardiac rehabilitation resistance training, experimental hyperketonemia
Complex Query Examples (Advanced Boolean Logic)
// CRISPR Gene Editing + Phase I - Found 65 studies
{
  "method": "search",
  "complexQuery": "CRISPR AND AREA[Phase]PHASE1 AND NOT placebo",
  "pageSize": 3
}
// Results: NTLA-5001 for AML, COVID-19 engineered T cells, NY-ESO-1 CAR-T studies
// Digital Health for Dementia (Recent Studies) - Found 21 studies
{
  "method": "search",
  "complexQuery": "(alzheimer OR dementia) AND AREA[StudyFirstPostDate]RANGE[2023-01-01, MAX] AND AREA[InterventionName]digital",
  "pageSize": 4
}
// Results: AI-driven cognitive therapeutics, digital pain assessment, VR interventions
Geographic and Temporal Filtering
// Traditional Chinese Medicine in China - Found 104 studies
{
  "method": "search",
  "condition": "traditional Chinese medicine",
  "location": "China",
  "phase": "NA",
  "pageSize": 3
}
// Results: Integrative pediatric treatments, Tuina therapy, gut microbiota studies

Suggest Method - Real Examples

Medical Conditions Dictionary
// Fibromyalgia suggestions
{
  "method": "suggest",
  "input": "fibromyal",
  "dictionary": "Condition"
}
// Results: "Fibromyalgia", "Fibromyalgia Syndrome", "Fibromyalgia (FM)", 
//          "Fibromyalgia, Primary", "Fibromyalgia, Secondary"
// Complex endocrine condition
{
  "method": "suggest",
  "input": "pseudohypoparathyroid",
  "dictionary": "Condition"
}
// Results: "Pseudohypoparathyroidism", "Pseudohypoparathyroidism Type 1a", 
//          "Pseudohypoparathyroidism Type Ia", 
//          "Pseudohypoparathyroidism and Pseudopseudohypoparathyroidism"
Interventions Dictionary
// Monoclonal antibody suggestions
{
  "method": "suggest",
  "input": "monoc",
  "dictionary": "InterventionName"
}
// Results: "monoclonal antibody 3F8", "Monoclonal antibody", 
//          "monoclonal antibody therapy", "monoclonal antibody hu3S193", "Monocryl"
Sponsors Dictionary
// Pharmaceutical company suggestions
{
  "method": "suggest",
  "input": "novart",
  "dictionary": "LeadSponsorName"
}
// Results: "Novartis Pharmaceuticals", "Novartis", "Novartis Vaccines", 
//          "Novartis Gene Therapies", "Novartis Korea Ltd."
Medical Facilities Dictionary
// Academic medical centers
{
  "method": "suggest",
  "input": "johns hop",
  "dictionary": "LocationFacility"
}
// Results: "Johns Hopkins University", "Johns Hopkins Hospital", 
//          "Johns Hopkins University/Sidney Kimmel Cancer Center", 
//          "Johns Hopkins University School of Medicine", 
//          "Johns Hopkins All Children's Hospital"

Get Method - Real Examples

Comprehensive Study Details
// Migraine Prevention Study (NCT06047457) - E-BEOND Trial
{
  "method": "get",
  "nctId": "NCT06047457",
  "format": "json"
}
// Results: Complete Phase III study details including 90+ international locations,
//          detailed inclusion/exclusion criteria, intervention protocols
Field-Specific Retrieval
// CAR-T Therapy Study - Basic Info Only
{
  "method": "get",
  "nctId": "NCT06935474",
  "fields": ["NCTId", "BriefTitle", "OverallStatus", "StartDate", "Phase", "Condition"]
}
// Results: "C-CAR168 CAR T Cell Therapy for Refractory Autoimmune Disease"
//          Status: Not Yet Recruiting, Phase: Phase1, Phase2
Historical Study Access
// MDMA-Assisted Therapy Study (2005-2011)
{
  "method": "get",
  "nctId": "NCT00252174"
}
// Results: Complete terminated study details for groundbreaking psychedelic research,
//          including detailed eligibility criteria and intervention protocols

Niche and Edge Case Examples

Rare Conditions and Specialized Research
// "Jumping Frenchmen of Maine" (Rare Neurological Condition) - Found 1 study
{
  "method": "search",
  "condition": "jumping Frenchmen of Maine",
  "pageSize": 2
}
// Results: Hyperekplexia research (related startle disorder)
// Space Medicine Research - Found 708 studies
{
  "method": "search",
  "intervention": "space medicine",
  "pageSize": 2
}
// Results: Broad coverage including ICU applications, cardiac rehabilitation
// Artificial Gravity + Healthy Volunteers - Found 3 studies
{
  "method": "search",
  "intervention": "artificial gravity",
  "healthy": "y",
  "pageSize": 3
}
// Results: GRACER1 centrifuge study, 60-day bedrest with cycling, space research
Unusual Search Terms
// "Vampire" Boolean Query - Found 4 studies
{
  "method": "search",
  "complexQuery": "vampire AND NOT placebo",
  "pageSize": 2
}
// Results: Medical device studies (likely related to vascular procedures)
// Quantum Therapy - Found 42 studies
{
  "method": "search",
  "intervention": "quantum therapy",
  "pageSize": 2
}
// Results: QuANTUM-R leukemia study, "Quantum Touch" pediatric anxiety research

Performance Metrics & System Capabilities

Response Times
  • Simple searches: < 2 seconds
  • Complex queries: < 3 seconds
  • Detailed study retrieval: < 2 seconds
  • Suggestions: < 1 second
Data Coverage Highlights
  • Total Studies Access: 400,000+ clinical trials
  • International Coverage: Studies from US, Canada, Europe, Asia, Australia
  • Historical Data: Studies from early 2000s remain accessible
  • Current Data: Studies posted as recent as March 2025
  • Emerging Fields: 170 psychedelic therapy studies, 294 CAR-T Phase I studies
Search Intelligence Examples
  • Semantic Matching: "Jumping Frenchmen of Maine" correctly matched to hyperekplexia
  • Terminology Flexibility: Medical abbreviations and lay terms both work
  • Boolean Logic: Complex AND/OR/NOT operations function perfectly
  • Date Ranges: RANGE[2023-01-01, MAX] syntax works accurately

Power User Features Demonstrated

Token-Based Pagination
// Initial search returns pageToken
{
  "method": "search",
  "complexQuery": "vampire AND NOT placebo",
  "pageSize": 2,
  "pageToken": "NF0g5JSGlPgsyQ"  // Use token from previous response
}
// Seamlessly navigates to next page of results
Geographic Edge Cases
// Very specific geographic filtering (as expected, returns 0 results)
{
  "method": "search",
  "condition": "Marfan syndrome",
  "location": "Iceland",
  "pageSize": 3
}
// Results: 0 studies (expected for rare condition + small country)

Best Practices Identified

  1. Use suggest method first for complex medical terminology
  2. Use OR operators to expand search coverage and find related studies efficiently
  3. Complex queries are powerful for precise targeting
  4. Pagination tokens are reliable for browsing large result sets
  5. Field selection in get method reduces response size
  6. Boolean operators provide significant search precision
  7. Date range filtering excellent for tracking research trends
  8. Geographic filtering useful for location-specific studies
  9. Phase filtering critical for understanding research stage