Data Exploration

Learn how to explore and filter the EHDS systematic review dataset.

Loading the Database

from ehdslens import EHDSAnalyzer

analyzer = EHDSAnalyzer()
analyzer.load_default_data()

db = analyzer.db
print(f"Loaded {len(db)} studies")

Accessing Individual Studies

By ID

study = db.get_study(1)
if study:
    print(f"Authors: {study.authors}")
    print(f"Year: {study.year}")
    print(f"Title: {study.title}")
    print(f"Journal: {study.journal}")
    print(f"DOI: {study.doi}")

Iterating All Studies

for study in db.studies:
    print(f"{study.authors} ({study.year})")

Searching

Search across authors, titles, and journals:

# Keyword search
results = analyzer.search_studies("privacy")

# Case-insensitive
results = analyzer.search_studies("GDPR")

# Partial matches work
results = analyzer.search_studies("feder")  # finds "federated"

Filtering

By Thematic Axis

from ehdslens.data import ThematicAxis

governance = db.filter_by_axis(ThematicAxis.GOVERNANCE_RIGHTS_ETHICS)
pets = db.filter_by_axis(ThematicAxis.SECONDARY_USE_PETS)

By Quality Rating

from ehdslens.data import QualityRating

high_quality = db.filter_by_quality(QualityRating.HIGH)

By Year Range

recent = db.filter_by_year(2024, 2025)

Combined Filters

# Using the analyzer's filter method
filtered = analyzer.filter_studies(
    axis=ThematicAxis.FEDERATED_LEARNING_AI,
    year_start=2023,
    min_quality=QualityRating.MODERATE,
    study_type=StudyType.EMPIRICAL
)

Custom Filters

# Direct filtering with comprehensions
empirical_2024 = [
    s for s in db.studies
    if s.year >= 2024
    and s.study_type in [StudyType.QUALITATIVE, StudyType.QUANTITATIVE]
]

Statistics

stats = analyzer.get_statistics()

# Available statistics
print(stats['total'])           # Total number of studies
print(stats['year_range'])      # (min_year, max_year)
print(stats['by_axis'])         # Count per thematic axis
print(stats['by_quality'])      # Count per quality rating
print(stats['by_type'])         # Count per study type

Citation Generation

study = db.get_study(1)

# APA format
print(study.get_citation(style="apa"))

# Vancouver format
print(study.get_citation(style="vancouver"))

Export Options

# To dictionary
study_dict = study.to_dict()

# Database to JSON
import json
data = [s.to_dict() for s in db.studies]
json_str = json.dumps(data, indent=2)