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GCRI · How Nexus works

Evidence

The evidence step decides what a question will be answered with: which methods and which data. Each assertion is labelled, so a reader can tell an observation from a model run or an expert judgement.

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01Sequence

The order things happen in.

  1. 01QuestionNational, regional or institutional priority
  2. 02EvidenceSTEM foundation of the platform
  3. 03BuildFoundry
  4. 04OrganiseNexus ecosystem
  5. 05TestUniverse (independent site)
  6. 06PublishReports
  7. 07DecideCompetent authorities and institutions, through NXS-RLS (participants, agreements and handoffs)
  8. 08RenewCorrections and the next annual agenda
02Six pillars

This step runs in Foundry.

Where methods, data and models become reproducible builds, each run with its inputs, version and limits on record. Go to Foundry.

Select pillars · hover lines18 / 18 handoffs

Route

Around Foundry

The pillars Foundry hands work to and receives it from.

L · F · U · S · R · A

Pillars
6 of 6
Handoffs
18 of 18
Loops
17 closed

Handoffs in play

  • F01Universe → Foundry · Admitted mission becomes a cycle project with a decision caseReadiness preparation
  • F02Foundry → Universe · Core Build Report and go or no-go evidenceControlled build
  • F03Foundry → Reports · Sealed observations and indicator series behind a profileCloseout
  • F04Universe → Reports · After-action and scenario findings for chapters 10 and 13After-action review

and 14 more

F01 to F14 are the recorded handoffs of the programme year, each with the artefact that moves and its phase; R1, R2, R3 and R4 carry work around the ring. A loop counts when every pillar on it is selected. Every pillar is led by the Nexus Consortium.
  1. LabsWhere questions become experiments and prototypes: new methods, data and tools are tried in the open, with their limits on record, before the Foundry builds them, under the Nexus Consortium.Labs at GCRI: Labs
  2. FoundryWhere methods, data and models become reproducible builds, each run with its inputs, version and limits on record.Foundry at GCRI: Foundry
  3. UniverseWhere a build is tested under controlled conditions with independent evaluators, so a method’s skill is measured, not assumed.Universe at GCRI: Universe technical officeuniverse.nexus
  4. Nexus StandardsWhere methods, identifiers and data schemas are codified in the open and corrected when a test finds a fault.Nexus Standards
  5. ReportsWhere findings are published with their method, uncertainty and evidence class, and corrected as new versions.Reports at GCRI: PublishReports
  6. Risk AcademyWhere methods and systems are taught on real data and real places, by working the case, on Risk Academy.Risk Academy
03Evidence labels

Every assertion carries the kind of evidence behind it.

A finding that mixes gauged river flow, a reanalysis product and a scenario projection is three different kinds of claim. The evidence step tags each assertion as observed, published statistics, modelled, estimated or expert judgement, and records the source, date and licence beside it.

LabelWhat it meansTypical check
ObservedMeasured by an instrument or survey with a known protocolInstrument metadata, gaps, homogenisation
Published statisticsPublished by a competent authority under its own rulesEdition, revision history, definitions
ModelledProduced by a model run with stated inputs and assumptionsValidation period, skill score, ensemble spread
Expert judgementElicited from named experts with a stated protocolElicitation method, calibration, dissent recorded
04Process

How the process runs.

Process

Evidence: PRISMA 2020 review reporting

PRISMA 2020 is a reporting guideline for systematic reviews; the steps follow its checklist, not a mandated sequence, and no Nexus document adopts it.

  1. 01 Plan

    1. 01Registration and protocolRecord · The review teamThe guideline asks for registration details, access to the protocol and any amendments.
    2. 02Eligibility criteriaRecord · The review teamThe guideline asks for the inclusion and exclusion criteria and how studies were grouped.

  2. 02 Find and select

    1. 03Search: sources and strategiesStep · The review teamThe guideline asks for the information sources and the full search strategies. It does not fix which sources are used.
    2. 04Selection of studiesStep · The review teamThe guideline asks how studies were judged eligible, including how many reviewers screened. It does not fix the number of reviewers.
    3. 05Flow diagramRecordThe flow diagram shows the number of records found, the number of studies included and the reasons for exclusion.

  3. 03 Analyse

    1. 06Data collectionStep · The review teamThe guideline asks how data were collected from reports and which data items were sought.
    2. 07Risk of biasStep · The review teamThe guideline asks for the methods and tools used to assess risk of bias.
    3. 08SynthesisModel · The review teamThe guideline asks for the effect measures and the synthesis methods. It does not prescribe meta-analysis.
    4. 09Certainty of evidenceStep · The review teamThe guideline asks for the methods used to assess certainty, and reports the result per outcome. It does not name a grading scale.

  4. 04 Report

    1. 10Review reportRecordThe guideline helps authors report why the review was done, what they did and what they found.

ReportsOutline of an externally published reporting guideline, not a Nexus process and not a record of operation. PRISMA 2020 mainly covers reviews of intervention effects. No Nexus page names it. Every programme is at service level R0.

05Appraisal

How evidence is weighed before it reaches a build.

Uncertainty language follows the IPCC calibrated language for confidence and likelihood where climate evidence is concerned, and certainty of evidence in health questions follows GRADE. Risk assessment technique selection is read against IEC 31010, the companion to ISO 31000.

  • Methods come from the STEM Commons, where each method page states its validation and limits.
  • Data products enter through Registry with provenance and licence recorded.
  • Gaps are written down as gaps: an unanswered part of the question is not filled with a proxy without saying so.
06Across the institutions

Each pillar’s contribution.

07Next

Then: build.

Build: foundry

08Sources

Where this page’s references lead.

The bodies and documents this page is read against. Status and editions change; each link goes to the issuing body.

The Global Centre for Risk and Innovation

Bring a method, a dataset or a question.

Information and enquiries are open today. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.

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