Cross-interview synthesis is the highest-leverage AI task in discovery — and the one with the signature failure mode: hallucinated evidence. This playbook extracts themes from a batch of transcripts where every theme carries quote-level citations, then spot-verifies each quote against its source before anything reaches a strategy doc.
Workflow area: Discovery & Research · Tier: Foundation · Hands-on time: ~30 minutes
Six interviews used to mean an afternoon with sticky notes. A model does the first clustering pass in minutes — but a model asked for themes will produce confident themes whether or not the transcripts support them, complete with plausible-sounding quotes no one ever said. The citation-and-audit discipline in this playbook is not optional polish; it is the difference between synthesis and fiction.
Assemble the reviewed notes or full transcripts with stable IDs. Label each source (INT-01, INT-02...) with persona and date. Stable IDs are what make citations checkable later.
Run the synthesis prompt with citations mandatory. In Claude (large context handles a full batch) or ChatGPT:
You are synthesizing user research for a product team.
Research question: [WHAT WE WANTED TO LEARN — e.g. "why do mid-market
customers stall in onboarding?"]
Below are [N] interview transcripts labeled INT-01 through INT-[N].
Produce:
1. THEMES — 4-7 themes, each with:
- a one-line claim stated as a finding, not a recommendation
- how many of the [N] interviews support it (count + IDs)
- 2-3 verbatim quotes as evidence, each cited as
(INT-ID, timestamp)
2. CONTRADICTIONS — where interviewees disagree with each other,
with cited quotes on both sides.
3. OUTLIERS — strong signals from only one interview.
4. NOT FOUND — questions from the research question the transcripts
do not answer.
Rules: every quote must appear verbatim in a transcript — never
compose, merge, or clean up quotes. A theme supported by fewer than
2 interviews goes to OUTLIERS. If evidence is thin, say so.
[PASTE ALL TRANSCRIPTS, EACH PRECEDED BY ITS ID LINE]
Read the output for shape before trusting content. Good output looks like:
THEME 3 — Admins fear bulk actions they can't undo (4/6: INT-01,
INT-03, INT-04, INT-06)
- "I exported everything to a spreadsheet first, just in case your
tool wrecked it" (INT-03, 18:40)
- "There's no undo, right? So I do ten records at a time" (INT-06,
09:12)
CONTRADICTIONS
- Pricing sensitivity: INT-02 calls the price "trivial" (22:10)
while INT-05 says it "nearly killed the renewal" (31:44).
A contradictions section with content and a non-empty NOT FOUND list are health signals. A synthesis where six humans agree on everything is a synthesis the model smoothed.
Run the citation audit — this is the step that earns your signature. For every theme, pick at least one cited quote and find it in the source transcript at the given timestamp. Log each check in a small table: quote, source, found-verbatim / found-paraphrased / NOT FOUND. One fabricated quote means you audit every quote in the doc, not just samples.
Demote or delete anything that fails. A theme whose evidence was paraphrased gets its real quotes substituted. A theme whose evidence doesn't exist dies, however plausible it sounds — plausible-but-unsupported is precisely what hallucination looks like.
Hand-write the "so what." The implications section — what this means for the roadmap — is judgment, and it is yours. AI clusters evidence; it does not know your strategy, your constraints, or your appetite for risk.
A batch of transcripts is a batch of personal data — synthesize only in your approved AI workspace with training disabled, and keep interviewee identities out of the synthesis doc itself; readers need personas, not names.
AI makes synthesis fast; the citation audit makes it true. A themes doc where every quote has survived a spot-check against source is evidence — anything less is a well-formatted opinion wearing your users' voices.