📊 StepChangeAnalysis.com — StepChange Analyzer

Built for healthcare improvers who need honest evidence of change  ·  Test your data, avoid tampering, know what to do when nothing changes.

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Statistical Evidence Table

📰 Articles & Case Studies

🏥️ NHS Healthcare Policy · Prospective Analysis

Corridor Care 2029 — What Bootstrap CUSUM Will and Won’t Find

The government aims to eradicate corridor care by end of Parliament. Four initiatives — Joiner level analysis applied in advance. The pre-committed prediction: Bootstrap CUSUM will not find a structural change point unless the discharge constraint is addressed at system level.

🏥️ NHS Healthcare Policy

The 66% Target: What the Dementia Diagnosis Data Actually Shows

England exceeded the dementia diagnosis target from 2017–2020. Then COVID produced the largest single-year fall in the series. Bootstrap CUSUM finds one stage, mean 65.39%. By March 2025 England is still 1.1 percentage points below a target set in 2012.

🏥️ NHS Healthcare Policy

More GP Appointments Recorded, Fewer Patients Feeling Seen

Bootstrap CUSUM on 80 months of NHS GP appointments data finds one finding that cuts through the political noise: GP doctor contact rates have not changed since 2018. The system grew. The GP contact rate didn’t. A system problem, not a people problem.

Healthcare Quality Improvement

Same Data, Three Charts, Three Very Different Stories

How X-mR, Run Chart, and Bootstrap CUSUM tell radically different stories from 488 weeks of clinical data — and why it matters for governance reporting.

🇬🇧 Economic Analysis

The Chart That Changes How You See 77 Years of UK Economic History

What Bootstrap CUSUM reveals about the long deceleration of UK GDP — and why conventional analysis has been telling us the wrong story.

⚙️ Industrial Process Monitoring

The Hydrogen Plant Problem — How Residual CUSUM Catches What Other Charts Miss

Two identical plants, a 17% efficiency gap, and the residual CUSUM monitoring system — built on one reading per shift, pen and paper — that solved it.

🏥️ NHS Healthcare Policy

Why Nothing Has Worked: NHS A&E and the Promise That Wasn’t Kept

Bootstrap CUSUM applied to 15 years of monthly data reveals four structural stages of decline. Not one policy intervention is detectable as an improvement. Tony Blair promised four-hour waits in 2000. Twenty-five years later, performance is worse.

🌿 Environment & Policy

ULEZ Worked — But Not When Anyone Expected

Bootstrap CUSUM on a decade of Marylebone Road NO2 data finds the ULEZ signal appeared 18 months before the scheme launched. But the biggest single change was COVID — and the London-wide expansion improved air quality at a site already in the zone for four years.

💊 Healthcare & Patient Safety

More Patients, Fewer Bleeds? What the Data Shows About Anticoagulation Safety Since DOACs Arrived

Bootstrap CUSUM finds three structural change points in NHS anticoagulation safety data. The DOAC adverse event rate fell 96% from peak. But even by 2019, half of DOAC prescriptions were still not adjusted for renal function. The improvement is real. The job is not done.

💊 Patient Safety · Never Events

Wholly Preventable: Ten Years of a Never Event That Never Stopped

The engineering solution has existed since 2010. The NHS declared wrong-route medication administration “wholly preventable.” Bootstrap CUSUM on six years of Never Events data finds one stage, no change point, mean 17.5 per year. Paul O’Neill fixed this at Alcoa. The difference is method.

🌿 Environment & Policy

The Grid Fixed Itself. Transport Didn’t.

The UK cut emissions 53% since 1990. Bootstrap CUSUM identifies three causes: energy market liberalisation (1998), the global financial crisis (2008), and the carbon price floor (2015). Only the last is climate policy. Transport shows no structural change at 95% confidence across 34 years.

💊 Patient Safety · Clinical QI

The Sepsis Six: Does Public Data Show Whether It Worked?

Six bedside actions. 96% of NHS hospitals. 37 countries. Bootstrap CUSUM on 22 years of ONS mortality data finds one stage and no change point in either clinical series. But the ratio between the two series shows a structural change point in 2013 at 95.5% confidence — the year the CQUIN coding incentive was introduced. Better coding. Not better outcomes. Not worse. The study step of PDSA was never completed.

📰 Articles & Case Studies

🏥️ NHS Healthcare PolicyCorridor Care 2029 — What Bootstrap CUSUM Will and Won’t Find 🏥️ NHS Healthcare PolicyThe 66% Target: What the Dementia Diagnosis Data Actually Shows 🏥️ NHS Healthcare PolicyMore GP Appointments Recorded, Fewer Patients Feeling Seen Healthcare Quality ImprovementSame Data, Three Charts, Three Very Different Stories 🇬🇧 Economic AnalysisThe Chart That Changes How You See 77 Years of UK Economic History ⚙️ Industrial Process MonitoringThe Hydrogen Plant Problem — How Residual CUSUM Catches What Other Charts Miss 🏥️ NHS Healthcare PolicyWhy Nothing Has Worked: NHS A&E and the Promise That Wasn’t Kept 🌿 Environment & PolicyULEZ Worked — But Not When Anyone Expected 💊 Healthcare & Patient SafetyMore Patients, Fewer Bleeds? Anticoagulation Safety Since DOACs Arrived 💊 Patient Safety · Never EventsWholly Preventable: Ten Years of a Never Event That Never Stopped 🌿 Environment & PolicyThe Grid Fixed Itself. Transport Didn’t. 💊 Patient Safety · Clinical QIThe Sepsis Six: Does Public Data Show Whether It Worked?