Independent prevention evidence, explained with limits
Prevention guidance makes more sense when you can see the numbers and the doubts
Read prevention guidance with context, numbers, and clear limits. Plain guides for adults and caregivers.
Four ways into the evidence
Make sense of study numbers
Plain explanations of risk figures, test-accuracy claims and outcome measures, so you can see what a health study’s numbers do and do not say.
Judge how strong the evidence is
See how study type, size, methods and evidence ratings affect how much confidence a body of research deserves, and where doubt remains.
Trace a claim back to its source
Learn to find where a claim began, tell document types apart, and check publication status, funding, registrations and corrections.
Bring evidence into your own situation
Work out whether information fits your circumstances, then prepare, track and share questions with your care team.
Prevention, vaccine and urinary-prostate topics we cover
We cover adult preventive care, vaccine evidence literacy, and questions about urinary and prostate health. We also write about risk communication and how to interpret guidelines, for adults and caregivers preparing for conversations on prevention, vaccination, urinary health, or prostate health.
Where this publication stops
We do not offer vaccination services or run political campaigns. We do not diagnose, and we do not give individualized screening or vaccine recommendations. We do not provide urology care, represent physicians, or give prescription advice.
How we handle changing evidence
Evidence changes, and sometimes we do not know yet. That is why each substantive guide shows a review date and a route for corrections. Every guide names its sources and separates guidance from evidence that is still uncertain. Our foundation pages carry no affiliate links, rankings, vendor calls to action or paid referrals.
How the research is done · Editorial policy · Corrections · Independence and domain history
Newest evidence explainers
- Best Study Methods for Medical Students: What Research Supports
- Relative vs Absolute Risk: What the Numbers Mean
- How to Calculate Relative Risk: Formula and Examples
- The 4 Phases of Clinical Trials: What FDA Review Means
- Top 5 Study Techniques: A Practical Guide
- Which Clinical Trials Pay the Most? Pay, Risk and Time
- Composite Endpoints: Which Events Actually Drove the Health Claim?
- Number Needed to Harm: Why the Time Period and Baseline Risk Matter
- Why Evidence Gets Downgraded: Five GRADE Questions in Plain Language
- Surrogate Outcome vs. Patient Outcome: What to Ask
- Corrections, Expressions of Concern, and Retractions: What They Mean for a Health Study
- Recommendation Strength vs. Evidence Certainty Explained
Latest guides
- Best Study Methods for Medical Students: What Research Supports
- Relative vs Absolute Risk: What the Numbers Mean
- How to Calculate Relative Risk: Formula and Examples
- The 4 Phases of Clinical Trials: What FDA Review Means
- Top 5 Study Techniques: A Practical Guide
- Which Clinical Trials Pay the Most? Pay, Risk and Time
- Composite Endpoints: Which Events Actually Drove the Health Claim?
- Number Needed to Harm: Why the Time Period and Baseline Risk Matter
- Why Evidence Gets Downgraded: Five GRADE Questions in Plain Language
- Surrogate Outcome vs. Patient Outcome: What to Ask
- Corrections, Expressions of Concern, and Retractions: What They Mean for a Health Study
- Recommendation Strength vs. Evidence Certainty Explained
- Why a Study Protocol and the Published Report May Not Match
- What a P-Value Can—and Cannot—Tell You About a Health Study
- How to Read a Health Test-Accuracy Claim Without Treating It as a Diagnosis
- How to Read a ClinicalTrials.gov Record Before You Read the Headline
- Statistical Significance and Practical Importance: Two Different Questions
- Patient-Generated Health Information: Questions Before Sharing Home Notes With a Care Team
- Questions to Ask When Health Information Seems Relevant but May Not Apply to You
- Why the Outcome Measured Matters in a Health Study