Complete firstSound survey design
Question, selection, analysis and anonymity are settled beforehand.
Otherwise criteria can be adjusted to favor a desired result.
Method guideDecision Making
Delphi Method
A practical method guide: clarify prerequisites and materials, understand the complete process, and look up outputs, pitfalls, and stop criteria.
ComplexityHigh
Time1-4 Wochen
Participants6-30 Experten
FormatAsync
MaturityCanonical
01
Prerequisite
What needs to be finished first
02
Preparation
What needs to be ready before start
Materials
Panel criteria, questionnaire, anonymous IDs and a procedure for medians, dispersion and arguments.
People / roles
Study lead, independent expert panel and analysts; disclose interests and affiliations.
Pre-read
Definitions of customer share and digital evidence, baseline information and the forecast horizon.
Time needed
2–3 rounds over several weeks; about 20–40 minutes per response.
Setup
Pilot the questionnaire, announce feedback and deadlines, and keep identities separate from published answers.
03
Core question
The one question this method answers
What share of our customers will require digital evidence by the end of 2028?
04
Flow
Phases with goal, actions, output and pitfall
Delphi elicits judgments from a deliberately selected panel whose members remain anonymous to one another. Following an independent first round, everyone receives the same aggregated feedback and may revise their judgment with reasons. Prespecified rules determine sufficient stability or consensus.
Delphi
Fictional example
Delphi elicits judgments from a deliberately selected panel whose members remain anonymous to one another. Following an independent first round, everyone receives the same aggregated feedback and may revise their judgment with reasons. Prespecified rules determine sufficient stability or consensus.
Question and panel
What defined quantity is judged by which expert perspectives?
Customer share requiring digital evidence by end-2028; five people from sales, compliance, purchasing, product and industry research.
Prespecified rules
Which scale, feedback and stopping rules apply?
0–100%; median, range and arguments. Stop after round 2 if median changes by ≤5 percentage points; otherwise maximum 3 rounds. Stability is not consensus.
Round 1
What anonymous judgments and reasons were submitted?
P1 30%, P2 40%, P3 50%, P4 60%, P5 80%; median 50%, range 50 points. Different assumptions about procurement cycles.
Feedback and round 2
What was returned and how did judgments change?
Everyone receives the same distribution and counterarguments. New estimates: 40, 45, 50, 55, 70%; median 50%, range 30 points; no attrition.
Conclusion
Which stopping rule applies and what remains uncertain?
Median change 0 points meets the stability rule. Report a stable panel midpoint of 50%, not consensus; P5 expects faster regulatory adoption.
All situations and people are fictional.
- 1
Protocol
Set panel and rules
Goal
Prespecified survey rules
Inputs for this step
- Question and selection criteria
Actions
- Pilot an unambiguous question with a horizon and scale; specify expertise and panel perspectives.
- Document anonymity, interests, feedback, a three-round maximum and stability threshold before responses.
Output
Prespecified survey rules
A purposively selected panel is not a random sample.
Quality check
Are selection, scale and stopping rules set before answers arrive?
Pitfall
Convenient contacts are presented as a representative expert panel. Recruit missing perspectives deliberately and report selection limitations.
Timing: 60–120 minutes
- 2
Elicit
Collect independent judgments
Goal
First-round distribution
Inputs for this step
- Piloted questionnaire
Actions
- Members respond without seeing other judgments; collect estimates and reasoning separately.
- Check completeness and clarify ambiguities without influencing the answer.
Output
First-round distribution
Independence precedes the first feedback.
Quality check
Were initial judgments independent of group feedback?
Pitfall
Participants coordinate answers outside the survey. Reinforce independence and rerun an affected round if necessary.
Timing: 20–40 minutes per person
- 3
Feedback
Return distribution and reasons
Goal
Reasoned subsequent round
Inputs for this step
- Anonymous distribution and reasoning
Actions
- Return median, range and balanced anonymous counterarguments, including minority views.
- Ask everyone the same question again and request reasons for changes or retained judgments.
Output
Reasoned subsequent round
Minority reasoning is relevant information.
Quality check
Does feedback include dispersion and counterarguments, not just the median?
Pitfall
Feedback implies that outliers should conform. Use neutral wording and explicitly allow unchanged, reasoned judgments.
Timing: 1–2 weeks response window per round
- 4
Conclude
Report stability and disagreement
Goal
Panel report with limits
Inputs for this step
- All rounds and attrition log
Actions
- Compare rounds against prespecified criteria, accounting for attrition and panel changes.
- Publish judgment, uncertainty, remaining disagreement and limitations without claiming forecast certainty.
Output
Panel report with limits
Stability concerns changes across rounds; consensus concerns agreement.
Quality check
Are stopping rules, attrition and remaining disagreement traceable?
Pitfall
A stable median conceals widely dispersed individual judgments. Separate stability from consensus and report the full distribution.
Timing: 60–90 minutes
05
Artifact
What comes out at the end
Sketch: what the artifact looks like
Form
A comparison of rounds including response counts, distributions, reasoning, attrition and uncertainty.
Versioning / ownership
Archive each questionnaire and feedback version; disclose changes to questions separately.
Tool alternatives
- Survey system
- Anonymous response table
- Analysis protocol
delphi-method-working-template.md
Refine independent expert judgments through feedback rounds while retaining disagreement.
Delphi Method: Worksheet
Question
To be confirmed
Desired outcome
To be confirmed
Scope
Plan the survey Time: 2–3 rounds over several weeks; about 20–40 minutes per response.
Complete this worksheet on paper or in your own document during the work.
Preparation for this scope
Method setup
- Materials: Panel criteria, questionnaire, anonymous IDs and a procedure for medians, dispersion and arguments.
- Roles: Study lead, independent expert panel and analysts; disclose interests and affiliations.
- Advance information: Definitions of customer share and digital evidence, baseline information and the forecast horizon.
- Overall time needed: 2–3 rounds over several weeks; about 20–40 minutes per response.
- Setup: Pilot the questionnaire, announce feedback and deadlines, and keep identities separate from published answers.
Prepare for the work steps
Protocol: Set panel and rules
- Question and selection criteria
Elicit: Collect independent judgments
- Piloted questionnaire
Feedback: Return distribution and reasons
- Anonymous distribution and reasoning
Conclude: Report stability and disagreement
- All rounds and attrition log
Delphi
Question and panel
What defined quantity is judged by which expert perspectives?
...
Prespecified rules
Which scale, feedback and stopping rules apply?
...
Round 1
What anonymous judgments and reasons were submitted?
...
Feedback and round 2
What was returned and how did judgments change?
...
Conclusion
Which stopping rule applies and what remains uncertain?
...
Enter your own information; connect open commitments to a next action.
RAND · Methodological Guidance for Delphi Panels
Protocol: Set panel and rules
Expected artifact: Prespecified survey rules
A purposively selected panel is not a random sample.
Entry:
...
- Are selection, scale and stopping rules set before answers arrive?
Elicit: Collect independent judgments
Expected artifact: First-round distribution
Independence precedes the first feedback.
Entry:
...
- Were initial judgments independent of group feedback?
Feedback: Return distribution and reasons
Expected artifact: Reasoned subsequent round
Minority reasoning is relevant information.
Entry:
...
- Does feedback include dispersion and counterarguments, not just the median?
Conclude: Report stability and disagreement
Expected artifact: Panel report with limits
Stability concerns changes across rounds; consensus concerns agreement.
Entry:
...
- Are stopping rules, attrition and remaining disagreement traceable?
Open questions and next steps
...
Method guide: https://methodatlas.meierhoff-systems.de/en/methods/delphi-method/run-sheet
06
Example output
Concrete filled scenario, fictional example
Fictional example for orientation. Counts and timings describe this case and are not universal requirements.
delphi-method-beispiel.md
Concrete filled scenario, fictional example
Fictional example
Question and panel: Customer share requiring digital evidence by end-2028; five people from sales, compliance, purchasing, product and industry research.
Prespecified rules: 0–100%; median, range and arguments. Stop after round 2 if median changes by ≤5 percentage points; otherwise maximum 3 rounds. Stability is not consensus.
Round 1: P1 30%, P2 40%, P3 50%, P4 60%, P5 80%; median 50%, range 50 points. Different assumptions about procurement cycles.
Feedback and round 2: Everyone receives the same distribution and counterarguments. New estimates: 40, 45, 50, 55, 70%; median 50%, range 30 points; no attrition.
Conclusion: Median change 0 points meets the stability rule. Report a stable panel midpoint of 50%, not consensus; P5 expects faster regulatory adoption.
07
Pitfalls
Recognize symptoms and steer against them
Quick overview, the full text is in the matching phase in the flow
- Set panel and rulesConvenient contacts are presented as a representative expert panel.View in phase
- Collect independent judgmentsParticipants coordinate answers outside the survey.View in phase
- Return distribution and reasonsFeedback implies that outliers should conform.View in phase
- Report stability and disagreementA stable median conceals widely dispersed individual judgments.View in phase
Trap
Set panel and rules
Symptom
Convenient contacts are presented as a representative expert panel.
What to do
Recruit missing perspectives deliberately and report selection limitations.
Trap
Collect independent judgments
Symptom
Participants coordinate answers outside the survey.
What to do
Reinforce independence and rerun an affected round if necessary.
Trap
Return distribution and reasons
Symptom
Feedback implies that outliers should conform.
What to do
Use neutral wording and explicitly allow unchanged, reasoned judgments.
Trap
Report stability and disagreement
Symptom
A stable median conceals widely dispersed individual judgments.
What to do
Separate stability from consensus and report the full distribution.
08
Stop criteria
When to pause, resolve prerequisites, or choose another approach
Add missing expert perspectives or limit the claimed scope before starting.
At the maximum number of rounds, report disagreement rather than forcing convergence.
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