Purpose
Assess how strong the evidence actually is behind a social program or intervention — classifying each study by research design, scoring validity, and assigning an overall evidence tier — so program leaders can defend impact claims, prioritize interventions, and know exactly what evidence is still missing.
When to Use
Invoke this skill when the user asks to:
- Evaluate whether a program's impact claims are backed by credible evidence
- Rate an intervention against an evidence-tier framework before adopting or funding it
- Distinguish causal evidence (RCTs, quasi-experimental) from weaker correlational or anecdotal claims
- Prepare an evidence summary for a funder, board, or grant application
- Identify gaps in the evidence base and plan studies to close them
- Compare several programs on evidence strength to prioritize investment
Inputs Required
Before starting, collect:
- Program/intervention name: What is being evaluated and what it aims to change
- Theory of change or intended outcome: The primary outcome(s) the program claims to affect
- Evidence sources: The studies, evaluations, reports, or data available — titles, designs if known, sample sizes, findings
- Population and context: Who the program serves and where (setting, geography, scale)
- Decision at stake: What this evaluation will inform (funding, adoption, scaling, reporting)
- Standard to apply: Preferred evidence framework if any (e.g., ESSA tiers, HomVEE, What Works Clearinghouse) — otherwise the default tiered framework is used
If study designs or sample sizes are not provided, infer them from the source descriptions and flag every inference as an assumption to verify.
Instructions
Step 1: Inventory and Classify Each Evidence Source
For every study or source provided, capture and classify:
- Design type, using this hierarchy from strongest to weakest:
- RCT (Randomized Controlled Trial): Random assignment to treatment/control — strongest for causal claims
- Quasi-Experimental (QED): Comparison group without randomization (matched groups, regression discontinuity, difference-in-differences, interrupted time series)
- Pre-Post / Single-Group: Same group measured before and after, no comparison group — cannot isolate cause
- Observational / Correlational: Cross-sectional or cohort analysis showing association, not causation
- Descriptive / Monitoring Data: Outputs, participation counts, satisfaction — describes activity, not impact
- Anecdotal / Testimonial: Stories, case examples, single-participant reports
- Outcome measured: Does it match the program's primary intended outcome, or a proxy?
- Sample size and attrition: Note underpowered samples (small N) and high dropout
- Independence: Was the study independent or self-conducted/funder-commissioned?
- Replication: Has the finding been reproduced in another sample or setting?
Step 2: Score Internal Validity (Can We Trust the Causal Claim?)
For each study, flag threats to internal validity:
- No comparison/control group (cannot rule out that change would have happened anyway)
- Selection bias (participants differ systematically from non-participants)
- High or differential attrition (over ~20% dropout, or dropout differing between groups)
- Confounding events during the study period
- Outcome measured only immediately, with no durability check Rate internal validity: Strong / Moderate / Weak / None.
Step 3: Score External Validity (Does It Transfer to This Context?)
Assess how well the evidence applies to the buyer's population and setting:
- Population match: Study sample vs. the population this program serves
- Setting match: Delivery context, dosage, and scale
- Implementation fidelity: Was the studied version the same as what will be delivered? Rate external validity: High / Partial / Low.
Step 4: Assign the Overall Evidence Tier
Based on the strongest credible evidence and its consistency, assign one tier:
- Tier 1 — Well-Built (Strong) Evidence: At least one well-conducted RCT, or two or more strong QEDs, showing a favorable effect on the intended outcome, with acceptable sample size, low attrition, and ideally independent replication
- Tier 2 — Moderate Evidence: A single well-conducted QED, or an RCT with notable limitations, showing favorable effects but not yet replicated or with external-validity concerns
- Tier 3 — Preliminary Evidence: Pre-post or correlational studies suggesting a favorable trend, or a promising pilot, but no comparison group to establish cause
- Tier 4 — No Reliable Evidence: Only descriptive, monitoring, or anecdotal information; or studies with fatal validity threats; or a compelling theory of change with no impact evaluation yet State the tier plainly and give a 2–3 sentence justification tied to the specific studies.
Step 5: Gap Analysis
Identify what is missing to reach the next tier:
- The single most important design weakness across the current evidence
- Whether the primary outcome is even being measured (vs. proxies or outputs)
- Whether findings have been replicated or tested at scale
- Whether the evidence applies to the actual population served
Step 6: Evidence-Strengthening Plan
Recommend concrete next steps ranked by cost and rigor gain:
- The most feasible study design to move up one tier (e.g., add a matched comparison group)
- What to measure and when (baseline, endline, follow-up for durability)
- Quick wins to improve current data quality (fidelity tracking, standardized outcome measures)
- What to say honestly to funders/boards given the current tier
Output Format
- Structure: An evidence-classification table for all sources, followed by narrative scoring, a single overall tier verdict, and forward-looking recommendations
- Length: 800–1,200 words
- Format: Table for the source inventory; structured bullets for validity scoring; prose for the tier verdict and plan
- Sections: Evidence Inventory (table) → Internal Validity → External Validity → Overall Evidence Tier (verdict) → Gap Analysis → Evidence-Strengthening Plan
- Tone: Rigorous and candid — a MEL specialist who will not overstate weak evidence, delivering an honest tier even when it's Tier 4
Quality Checklist
Before delivering output, verify:
- [ ] Every source provided is classified by one of the six design types
- [ ] Each study has both an internal-validity rating and an external-validity rating
- [ ] A single overall evidence tier (1–4) is assigned with justification tied to specific studies
- [ ] Any inferred study designs or sample sizes are explicitly flagged as assumptions
- [ ] The gap analysis names the specific weakness blocking the next tier — not a generic "more research needed"
- [ ] The strengthening plan specifies at least one concrete, feasible study design to advance one tier
Notes
- Do not inflate the tier to be encouraging — a Tier 4 verdict delivered honestly is more useful than a Tier 2 verdict that collapses under funder scrutiny
- A strong theory of change is not evidence of impact; classify it as Tier 4 until an outcome evaluation exists
- Watch for outcome-swapping: programs often cite strong evidence for a proxy (e.g., attendance) while claiming impact on the real goal (e.g., graduation)
- When multiple studies conflict, weight by design strength and independence, not by recency or headline effect size
- If the buyer names a specific framework (ESSA, WWC, HomVEE), map the overall tier to that framework's language in the verdict so it's usable in their reporting
How to use this skill
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Installing in Claude Code:
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- Drag this file into a new chat, or copy and paste its contents
- Send your task or request as your next message — the AI will apply the skill where it fits
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