Mobility Atlas research: electric-wheelchair-guide
Data and method for the article at mobilitatlas.com/blog/electric-wheelchair-guide/
License: CC BY 4.0 (credit "Mobility Atlas")
Prepared: 10 October 2026

WHAT WAS READ
FDA MAUDE medical device reports under product code ITI (Wheelchair, Powered), received 1 January 2024 to 27 August 2026 (the latest data in openFDA on 10 October 2026), downloaded through openFDA (api.fda.gov) on 10 October 2026. 1,296 reports downloaded; 29 carry no text; 1,267 coded.
FDA recall records for the same product code, downloaded through openFDA the same day.

HOW IT WAS CODED
1. A codebook (codebook.txt) was written before any report was coded. Its SHA-256 fingerprint, recorded at 2026-10-10T05:55:31Z, is 7da2d5981098428581aa6fa7858d0ee73c33910f5e4643bb3f034e33570ee787. Any later change to the codebook would change this fingerprint.
2. The reports were split into chunks. Two coders (AI language models working separately, each without access to the other's answers) coded every report in every chunk against the codebook.
3. Agreement between the two coders: device 97.2% (kappa 0.932); category 98.5% (kappa 0.965); injury 99.0% (kappa 0.965); fall 99.7% (kappa 0.989); retrospective filing 100% (kappa 1.0). Category among the 371 reports not branded SmartDrive: 95.1% (kappa 0.943).
4. Every report where the coders differed was decided by the lead analyst under written rules (below). 66 disagreements decided under rules R1 to R8; a consistency pass applying R1 to every Pride report changed 50 more.
5. Counts in the article were produced by script from the final table, not by hand. Some sub-counts in the article (for example parts named, places named) are keyword counts over the report text, and the article says so where it matters.

ADJUDICATION RULES
R1: DEVICE: the brand "Pride Mobility Products" alone does not tell a power chair from a scooter; such reports are C only when the narrative names a chair, wheelchair, Jazzy or Quantum, or a power-chair part (joystick, tilt, seat elevator, recline, AFP), and O otherwise. Applied to every Pride report in the consistency pass.
R2: INJURY = y only when the report states harm to the body or medical care: injury, wound, cut, burn, fracture, bruise, scrape, swelling, pain or soreness, concussion, hospital or ER. A stated impact alone ("hit his head", "pinned his hand", "landed on his leg") is n.
R3: A fall or tip-over with no device fault alleged is T even when the maker says the device was not at fault or an outside cause (a bus, a lift, a curb) is named; X is kept for events with no fall and no alleged fault.
R4: Harm from contact with an intact part (a cut, a crushed toe, a pinch) or a fit or supply complaint, with no part failing, is X.
R5: A motor that drives forward or keeps driving without the user intending it (including after the user grabs the rims, or a "bucking" lurch) is M; a power add-on that keeps driving because the user was still commanding it is not M.
R6: Rolling away because the freewheel or motor-lock lever slipped or did not hold, or sliding backwards on a slope or ramp, is B.
R7: One motor stopping, the chair stopping or not moving at all, or a control going dark is E.
R8: FALL = y only when the user left the seat or the device tipped; a belted user thrown forward in the seat is n.

QUALITY NOTES (disclosed in full)
- During coding, some coder runs took shortcuts: a few used scripts on near-identical templated reports instead of reading each one, and two runs briefly shared a scratch folder. Those chunks were re-run with stricter instructions (read every report, no keyword scripts, a private scratch folder). The agreement figures above are for the final runs.
- The article then went through three independent fact-check passes (a full pass, a second pass with a reader review, and a control pass over the changes), each recomputing numbers from the files here and reading quotes against their sources; every error found was corrected before publication.

AMOUNTS
Every report text was searched for money figures. One report (23832001) gives a figure, an owner's out-of-pocket "$2500 to $3000"; there is nothing to tabulate. Prices in the article are list prices from makers', dealers' and retailers' pages and the Mobility Atlas catalog, listed in electric-wheelchair-guide-documents.csv and the article sources.

LIMITS
- Reports are not rates. Nobody publishes how many devices of each model are in use.
- A report is an allegation or a description; the FDA says the submission of a report "itself does not necessarily demonstrate that the device caused or contributed to the adverse outcome or event."
- Counts follow paperwork: some makers filed many reports at once from reviews of old complaints (see the retro column).
- Reports with no text could not be coded.

FILES
codebook.txt        the codebook as fingerprinted
coded_reports.csv   one row per coded report: both coders' answers, the final code, and how a disagreement was resolved (resolution, rule_applied)
report_pool.csv     the reports in the pool with product code, brand, date received and event type
The full report texts are public: search MAUDE or openFDA by report key.
electric-wheelchair-guide-documents.csv  the documents and pages read, with links