Population
Humans with clinically and/or radiologically defined knee osteoarthritis.
PRP Evidence Transparency Initiative
PETI – PRP Evidence Transparency Initiative
PETI documents how transparently randomized PRP/PRGF reports in knee osteoarthritis describe the methods needed to understand and reproduce the intervention. PETI does not assess clinical efficacy, safety, treatment decisions, products, kits, brands, manufacturers or vendors.
Current PETI status
The methodology is prepared for formal approval and blind calibration. Public study assessments remain locked until the freeze gate has been passed.
Method statuscalibration-ready
Codebook v1.0not frozen
Public resultslocked
Page status24 Aug 2026
Why are there no study results yet?
PETI will publish scores, study profiles or aggregate metrics only after scope and methods have been formally approved, the predefined blind double-coding calibration has been completed and the freeze gate has been passed.
01
What PETI examines
PETI examines reporting quality, not the clinical quality of a treatment. The prepared v1.0 scope uses the following boundaries:
Intervention
At least one clearly separable arm using autologous intra-articular PRP or platelet-containing PRGF.
Design
Primary randomized controlled clinical reports; follow-ups only when they contain independently codable methods.
Period
Publications from 1 Jan 2020 through 31 Dec 2025.
Languages
English or German in the frozen PubMed search.
Search
PubMed / NCBI Entrez; PRGF-capable freeze search on 21 Aug 2026 with 305 records.
23MIBO-based reporting fields
305freeze-search records
2full-text languages
2020–2025publication period
02
The 23 reporting fields
PETI uses the 23 MIBO statements as its reference framework and breaks composite fields into traceable atomic subclaims. The groups below show what is assessed.
M01–M03 · Study design & demographics
Reporting guideline; ethics/institutional approval; age and sex.
M04–M08 · Participants & condition
Comorbidities; relevant medication; diagnosis, severity and chronicity; pre-intervention imaging including findings; previous treatments.
M09–M16 · Intervention & processing
Replicability of the intervention; operative findings where applicable; anticoagulant/whole-blood storage; whole-blood cell analysis; processing/centrifugation; platelet recovery; PRP storage; process timing.
M17–M19 · PRP characterization
PRP format; cell analysis of the final product; activation status and, for exogenous activation, agent, volume, concentration and procedure.
M20–M22 · Delivery & aftercare
Timing, number and interval of injections; delivered volume and accompanying materials; immobilization/activity and physiotherapy/rehabilitation.
M23 · Outcomes & complications
Functional outcomes and active capture of complications/adverse events.
03
How PETI codes reporting
The codes describe only whether information is visible and traceable in the verified report. They are not efficacy or quality grades.
Clearly reported
All applicable required subclaims are supported and linked to a source locator.
Partial / unclear
At least one required subclaim is present while at least one other is missing or unclear.
Not reported
No study-specific information was found after the complete field-specific full-text and supplement search.
Not applicable
The field is structurally not applicable under a predefined rule.
Unassessable
The required source basis cannot be verified; this is not treated as N.
04
Quality assurance before public release
Frozen scope
Search, PRGF boundary, follow-up and identity rules are fixed before calibration.
Verified sources
Full text, tables, figures and available supplements form the source basis.
Claim-to-Evidence
Each relevant decision receives a source locator; an N requires a documented search protocol.
Blind double coding
Two reviewers code the same calibration set separately without seeing each other’s decisions.
Comparison & adjudication
Differences are compared, documented and resolved only after both blind files are complete.
Versioned freeze
Only a passed gate permits Codebook v1.0 and later public data releases.
Predefined freeze gate
A freeze requires, among other criteria, at least 90% exact subclaim agreement and at least 90% main-code agreement. In addition, unresolved = 0 and rule_change_required = 0 are mandatory.
05
Transparency & governance
PETI is initiated and published by prpmed.de / prpmed Funkner e.K. Its commercial activity in the PRP market is openly disclosed. PETI is not described as institutionally independent.
Product neutrality
PETI does not assess products, kits, brands, manufacturers or vendors.
Independent second review
Public report-level data must undergo the defined methodologically independent second review and conflict resolution.
Versioning
Changes are documented; published decisions are not silently overwritten.
Corrections
Corrections, retractions and study-identity conflicts are checked again before release.
06
Status & updates
Historical PubMed pilot search: 300 records.
PRGF-capable freeze search v1.1: 305 records; retrieval and delta screening archived.
Methods package recorded as calibration-ready. Public results remain locked.
Formal scope/method approval, followed by a hashed five-report manifest and separated blind double coding.
07
Scientific foundations
PETI uses MIBO as a reference framework and explicitly distinguishes its own operationalization from earlier MIBO adherence reviews.
- Murray et al. 2017. Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO): Platelet-Rich Plasma and Mesenchymal Stem Cells. PubMed ↗
- Stone et al. 2024. Randomized Controlled Trials on Platelet-Rich Plasma for Knee Osteoarthritis Poorly Adhere to the MIBO Guidelines. PubMed ↗
- Nakagawa et al. 2025. Systematic Review of Randomized Controlled Trials Evaluating PRP for Knee Osteoarthritis: Adherence to MIBO. PubMed ↗
PETI. PETI is a PRPmed initiative for transparent documentation of scientific reporting.