Effectiveness, Efficiency and Efficacy

02 May

As I reflect upon my student days at The Welsh School of Medicine, Cardiff (now known as Cardiff University School of Medicine)  I realise how I was oblivious to the great opportunity of listening attentively to the lectures of Archie Cochrane , an epidemiologist who has dictated how Western Medicine is practised today. I have to say I was not enthralled by his lectures, which were largely composed of quoting various statistics, tables and numbers and certainly not my idea of studying medicine so it was not unheard of to dodge going to his lectures along with many of my peers. I vividly remember him strolling along the corridors usually smoking a pipe and I am afraid many of us were more interested in watching him roll up in his top of the range Jaguar than attending the lectures!

Archie joined the scientific staff of the recently formed Medical Research Council’s Pneumoconiosis Research Unit in Llandough Hospital, Penarth, near Cardiff (South Wales), in 1948 and initially conducted groundbreaking comparative studies of dust levels in the coal mines of South Wales.

Around one in twenty miners suffered some sort of disability from working in the pits. It was these men he recruited for the study. They were the key to its success, ensuring an astonishing response – more than 90 per cent of the population agreed to take part. Initially, he conducted groundbreaking comparative studies of dust levels in the coal mines of South Wales. Two years later, he launched the Rhondda Fach – Aberdare Valley (‘two valleys’) scheme to investigate the aetiology of progressive massive fibrosis.

Its main aim was to see if the common miners’ disease progressive massive fibrosis (PMF) was due to an interaction between pneumoconiosis and tuberculosis. In the end, it concluded that tuberculosis had relatively little or no impact.

Another of his main interests were the X ray classification of coal workers’ pneumoconiosis and the relationship he demonstrated between X ray categories, dust exposure and disability. His interest in this field continued for the rest of his life, as reflected in the completion during 1974-1986 of 20- and 30-year follow-up studies of the population of the Rhondda Fach.

Its real impact was to demonstrate that epidemiology – looking at the pattern of disease – could be carried out effectively in large-scale field studies as well as the laboratory. If Tredegar, the birthplace of Aneurin Bevan was the cradle of the NHS, the Rhondda Fach was its nursery.

Under Archie’s direction, the MRC Epidemiology Unit quickly established an international reputation for the quality of its surveys and studies of the natural history and aetiology of a wide range of common diseases, including anaemia, glaucoma, asthma and gallbladder disease. Indeed, the Vale of Glamorgan became the epidemiologically most well-defined area of the UK. These studies led naturally to Archie’s interest in the validation of screening strategies within the National Health Service. Indeed, he became a leading critic of the introduction of screening for cancer of the cervix on what he regarded as seriously inadequate evidence of its effects.

I  clearly remember this controversy and it made me understand the relevance of randomised controlled trials. An RCT, at its most elementary level, involves assigning patients to either the experimental group or the control group by using some method independent of human influence. This is the only way of proving a treatment is effective and it is the practice of carrying out RCT that has formed the backbone of Evidence Based Medicine.

It was assumed that an abnormal smear if left untreated would develop into a Cervical cancer but this had not been shown by carrying out a randomised trial but as screening was now well established at that time it would have been unethical to carry out such a trial. Otherwise, it had not been shown categorically that screening was beneficial in reducing the incidence of cervical cancer. Since that time trials have been carried out in other parts of the World comparing the death rate in a screened population and an unscreened population and proved the efficacy of cervical cancer screening.

I also remember at this time a trial was carried out comparing the death rate of those having heart attacks being hospitalised or staying at home. Those staying at home had a better survival rate. As a result of this publication  there was a policy that  patients were to be kept at home unless they developed complications or  needed to be hospitalised for other reasons. Subsequent trials around the country came up with different outcomes  as well as significant advances in cardiology so that the policy was reversed and Coronary Care Units evolved.

The uncomfortable truth which he highlighted in his 1971 Rock Carling lecture Effectiveness and Efficiency: Random reflections on health services,  was there was no good evidence for many medical intervention and treatments. Too often it was based on subjective ignorance (from fellow doctors, which didn’t endear Archie to many colleagues) rather than objective evidence from randomised controlled trials. The conclusions of the lecture given 44 years ago makes fascinating reading and bear a striking resemblance to how our Health Service is evolving today.

Since this time countless randomised controlled  trials of medical interventions and treatments have been carried out and now form the basis of evidence medicine which dictates how we practise medicine today. As I reflect on this I feel amazed that those lectures that I dodged along with many fellow students more than 40 years ago would be so significant. But somehow it has always been engrained in my thinking as a doctor simply because we had to remember the basics from the lectures in order to pass an examination. When I had a recent chest X-ray it showed that I must have had sub – clinical tuberculosis – so that I along with many others also proudly carry the scars of working with miners in South Wales. . Hence without realising it I was experiencing the influence of one of the most important pioneers of scientific method in medicine, Archie Cochrane.

Moreover, it is a sobering thought to think that it took nearly 30 years of Archie Cochrane’s extensive work with miners in demonstrating the association of mining  with disabling pneumoconiosis, the management of which played a major part in my early medical career, to be recognised as a disease warranting compensation.



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