About this model

Dr. Ahmed Hamdy Oreaba, FRCOphth, FRCS, MRCS

Participating centres

229

Eligible operations

546,974

Recorded PCR events

3,849

Observed PCR rate (unadjusted)

0.70%

Preceding audit-year observed PCR rate

0.69%

Audit period

1 April 2024 to 31 March 2025

Audit label

2024 NHS year

Document

2026/NOD/535, September 2026

The latest national observed rate and the model-development rate answer different questions. The 0.70% figure describes the unadjusted proportion of eligible operations affected by PCR in the 2024 NHS audit year. CataractStar calculates an individual estimated probability using the Report 17 coefficients derived from an earlier development dataset. The annual-report figure does not replace or recalibrate those coefficients.

Observed PCR fell from 1.36% in 2015 to 0.70% in 2024. This is historical national context, not an individual threshold or a target for every surgeon.

For the National Cataract Audit, PCR is a collective term covering posterior capsule rupture with or without vitreous prolapse, or zonular rupture with vitreous prolapse.

The 2026 NOD report describes PCR as being associated with:

• 20-fold risk of retinal detachment in the year after surgery.
• 17-fold risk of acute intraoperative suprachoroidal haemorrhage.
• 16-fold risk of losing at least 0.60 LogMAR from pre- to postoperatively.
• 7-fold risk of postoperative endophthalmitis.
• 6-fold risk of losing at least 0.30 LogMAR from pre- to postoperatively.

These are population-level associations and are not individual prognostic estimates produced by CataractStar.

The annual audit excludes operations that are not comparable with primary phacoemulsification, including cataract extraction undertaken as part of:

• Combined phaco-trabeculectomy
• Keratoplasty
• Pars plana vitrectomy

It also excludes relevant traumatic and posterior polar cataracts where the risk of PCR is considered independent of surgical care. These exclusions account for approximately 4.5% of submitted procedures.

• The model provides an estimated probability, not certainty.
• Important clinical variables may be absent from the model.
• The model does not replace assessment of the individual patient, surgeon competence, supervision or local governance.
• Posterior polar and traumatic cataracts were excluded from the development dataset where PCR was expected as part of the surgery.
• This prototype uses rounded publicly reported coefficients, so its figures differ very slightly from the source’s worked examples.
• Full-precision coefficients and regulatory validation would be required before routine clinical deployment.

Model version: RCOphth-NOD-Report17-published-rounded-coefficients-2025-09-10

The published coefficient table gives +0.107 per mm of anterior chamber depth, while the accompanying narrative discusses increased observed risk with shallow anterior chambers. This prototype follows the published coefficient table exactly and this discrepancy must be clarified with RCOphth NOD before any clinical release. The 2026 Annual Report does not resolve this discrepancy; CataractStar follows the published coefficient table exactly pending clarification from RCOphth NOD.

Every calculation runs in your browser. There is no database, authentication, server function, analytics, cookie, local storage or external API, and no patient-identifiable field exists anywhere in the application. Nothing you enter leaves your device, and nothing is retained once you close or reset the page.

• Report 17 full article (PMC11621766)
• RCOphth NOD Posterior Capsular Rupture statistical model — 2025/NOD/526, 10 September 2025 (PDF)
• RCOphth NOD Ninth Annual Report of the National Cataract Audit 2026 — 2026/NOD/535, September 2026 (PDF)
• RCOphth NOD Case Complexity Adjustment — 2026/NOD/530, February 2026 (PDF)
• MHRA guidance on clinical calculators (PDF)

Before public or commercial release, confirm permission to reproduce the model content and terminology and obtain written clarification of any coefficient or documentation uncertainty from RCOphth NOD.