Seventy-five years on that ambition largely remains, enshrined in the 2011 NHS Constitution of guiding principles and pledges to the public.

But the reality is different, with data revealing access to healthcare is getting worse, inequalities are growing, and stark differences across the country are leaving large sections of the population behind.

Your address, your ethnicity, your gender, and above all else your socio-economic status are strongly tied to how long and healthy your life will be.

Explore your area in the map below:

Postcode lottery - a north-south divide?

One of the places this gap between rich and poor is most pronounced is on The Wirral, which is home to both Birkenhead, an extremely deprived area with one of the lowest life expectancies, and Gayton, an affluent area with above average health.

Dr Laxman Ariaraj, a GP at Fender Way Health Centre who has been working in the Birkenhead area for 20 years, has witnessed health inequalities widen there over time.

He said: "Certainly access has become more difficult over that time, which would probably widen those wider determinants of health.

"The sheer volume of the people that we need to see is going to impact the amount of time we can spend doing things proactively.

"On a positive note, I think we've become more aware of it and that gives us an opportunity to try and do something about it."

The government has committed to cutting NHS waiting lists, however across the country little progress has been made. The North West, where Birkenhead is located, is the worst affected region with the longest waits.

The NHS operational target is that 92% of people should be treated within 18 weeks following referral by a consultant. However, two fifths of the current 7.4 million waitlist for treatments have been waiting for longer.

The North West has experienced the biggest increase in waits in England, from 13% on the list more than four months in April 2019 (around average compared to other areas), up to 46.1% in the latest data for April 2023.

Overall, the waiting list has increased by more than three million from 4,315,000 in April 2019. At that time 87% of would-be patients had been waiting less than 18 weeks.

The situation in the north generally and the North West in particular is of even more concern given the health inequalities that already exist here.

There are some extremely disadvantaged neighbourhoods with higher levels of deprivation than in any areas of the country, such as Blackpool, and this plays a big part in poor health outcomes.

However, this doesn't fully explain the health gap with other areas. At any cross section, London tends to have higher life expectancies, even though the areas are of similar socio-economic status:

There is no settled explanation for the phenomenon, but Dr Bola Owolabi, a GP in the Midlands and director of Health Inequalities at NHS England told Sky News that this may partly be explained by communities who are harder to track in official metrics.

Dr Owolabi said: "We recognise that there are other drivers beyond simply using the Index of Multiple Deprivation.

"For example, people experiencing homelessness or rough sleeping, and migrant communities may not show up in the data."

Deprived areas have less access to resources

The current NHS crisis and treatment backlog affects everyone, but it may not be affecting everyone equally.

Analysis by The Health Foundation has shown a decrease in the proportion of people admitted to hospital after presenting at A&E due to bed rationing.

The most significant drop in emergency admissions was seen among people living in the most deprived areas, by 80,000 between 2019 and 2022. This was more than twice as much as the 35,000 decrease for those living in the least deprived areas.

Although the total number of days patients spent in hospital increased in most areas, it decreased for patients in the most deprived areas.

Patients in the most deprived areas in the country had 107,000 fewer days in hospital beds in 2022 compared to 2019. The net increase in bed days for emergency admissions was 329,000.

The challenge of training and retaining enough doctors and other healthcare staff to plug vacancies has also been a major challenge for the NHS in recent years to meet the needs of a growing and ageing population.

But more deprived areas have additional challenges with recruitment.

Sky News analysis has found that the local GP for someone living in one of England's most deprived areas has, on average, a 61% higher patient workload than the average local GP for residents of the country's wealthiest areas.

This gap has increased slightly since 2015, when it stood at 59%. That's despite the government's efforts to incentivise trainees to take up posts in under-served areas.

"The pressure on the NHS is potentially damaging the health of poorer people."

The Marmot Review on health inequalities, first published in 2010 with a ten year follow up in 2020, concluded that inequalities in health and life expectancy result from social issues including employment, housing and deprivation.

Professor Sir Michael Marmot, director of The UCL Institute of Health Equity, told Sky News: "I've been saying for a long time that given the equity of access in the NHS, it's highly unlikely that difficulties of access to treatment are playing a big role in the inequalities in health. I may need to modify that conclusion in the light of recent history.

"You've got it both ways: that the pressure on the NHS is potentially damaging the health of poorer people. And that the poor health of poorer people - because of social and economic inequalities in society - is potentially putting unbearable burden on the NHS."

Ethnicity based inequalities

People from ethnic minority backgrounds tend to be disproportionately affected by deprivation.

Data from Ministry of Housing, Communities & Local Government suggests that ethnic minorities are far more likely to live in the most deprived 10% of neighbourhoods. 

They are also more likely to live in overcrowded conditions and low-income households - defined as living on less than 60% of the average net disposable household income. 

According to data from the latest census, more than a fifth of people from Asian backgrounds live in overcrowded conditions (having less than the required number of bedrooms).

People from black backgrounds are 6 times more likely to be living in overcrowded households than white people. 

Access to primary care health services is generally equitable for ethnic minority groups.  

However, people from ethnic minority groups are more likely to report being in poorer health and have higher mortality rates.

Research from the Health Foundation's REAL Centre suggests that individuals from South Asian backgrounds, particularly Bangladeshi and Pakistani, have higher incidences of diagnosed chronic pain, diabetes, and cardiovascular disease.  

The prevalence of diagnosed chronic pain is around three fifths higher among Bangladeshi and Pakistani individuals compared to white individuals.

People from black African ethnicities also have a higher prevalence of chronic pain. 

Chronic pain among other conditions is also prevalent in deprived neighbourhoods. The prevalence of diagnosed chronic pain is more than double in the most deprived neighbourhoods compared to the least deprived neighbourhoods. 

However, cancer is more prevalent for people from white backgrounds and almost double than for people from South Asian backgrounds.

Hope for addressing health inequalities

The National Healthcare Inequalities Improvement Programme was set up in 2021 to tackle healthcare inequalities and ensure equitable access to healthcare and it does provide some hope for tackling health inequalities.

The programme works to deliver projects and services targeted at people living in the most deprived areas in England and others who are disadvantaged.

This includes improving access to digital services and helping people gain employment.

Dr Owolabi said: "The NHS, as a commissioner, and provider of services, is able to materially influence health inequalities."

Many cities have decided to focus extensively on implementing the policy changes envisaged by Marmot in his review.

These cities have been named 'Marmot cities' and have seen significant improvement in health inequalities.

There may be some early signs of success with the programme. Coventry was one of the first of these cities to adopt Marmot principles, and in the time since, Professor Marmot says: "The percentage of children aged five with a good level of development went up...

"The percentage of 18 to 24 year olds not in employment, education or training went up. And the proportion of people earning a real living wage went up."

Sky News has contacted the Department of Health and Social Care for a response to our findings.

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The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.