When: waypoints/meta.json exists, waypoints/epidemiology.json doesn't.
Characterize this patient population: how they're identified, how many there are, and what happens to them over time.
Step 1: Diagnostic criteria and population definition - WebSearch for consensus diagnostic criteria (e.g., EWGSOP2 for sarcopenia, GOLD for COPD) - Identify how this population is clinically identified and distinguished from related populations - Note if criteria are evolving or contested - For non-standard indications: document what proxy definitions exist (research criteria, clinical trial enrollment criteria, expert consensus)
Step 2: Prevalence and incidence - Search pubmed MCP for recent systematic reviews and meta-analyses on prevalence - WebSearch for CDC, WHO, or national registry data - Capture: global prevalence, US prevalence, incidence rates, trends over time - Distinguish between community-dwelling and clinical populations where relevant - Note data quality: are estimates from large epidemiological studies or small single-center studies?
Step 3: Demographics and risk factors - Age distribution, sex differences, racial/ethnic disparities - Key risk factors and comorbidities - Geographic variation if significant
Step 4: Natural history and disease progression - Typical disease course (acute vs chronic, progressive vs relapsing) - Staging systems if applicable - Mortality and morbidity data - Key inflection points in disease trajectory (when intervention matters most)
Step 5: Write waypoints/epidemiology.json
Follow the schema from references/waypoint-schemas.md. For each subsection, note coverage level.