A Review of the Literature: Does the Inverse Care Law Still Apply Today?

This literature review will first describe what is meant by the ‘Inverse Care Law’ as defined by Julian Tudor-Hart in his original paper and assess whether or not this law is still in effect. In order to do this, five studies exploring the Inverse Care Law will be evaluated, including one that shows evidence against the existence of the Inverse Care Law. It is eventually concluded that the majority of sociological studies as well as the literature on the subject, provide support for the argument that the Inverse Care Law still exists today, though it is less clear that its source is in market forces as Hart maintained. Instead it is suggested that the source of the problem lies in the socioeconomic status of individual patients and the interpersonal relations between General Practitioners (GPs) and patients that correspond to this. Finally further research to test this hypothesis is considered.

What is the Inverse Care Law?

In 1971 Julian Tudor Hart coined the term ‘Inverse Care Law’ (Hart, 1971:1), though the theory itself had already been recognised by previous writers such as Titmuss, that ‘higher income groups know how to make better use of the service; they tend to receive more specialist attention’ and overall better care (Hart, 1971:1). It was known, even then, that those of a lower socio-economic background tended to have poorer health and so Hart formalised these observations with his theory that ‘The availability of good medical care tends to vary inversely with the need for the population served’ (Hart, 1971:1) – those who require the most care actually receive the least, and of a lesser standard. This first part of Hart’s theory is often quoted, but as Hart recently recognised himself, most forget the second half of his theory (Hart, 2000:18), that the Inverse Care Law ‘operates more completely where medical care is most exposed to market forces, and less so where such exposure is reduced’ (Hart, 1971:1), namely that this pattern of inequality is driven by profit.

Whilst Hart did not present data of his own in his first writings, he did draw on the findings of others to support his theory, such as Ann Cartwright’s study of 137 randomly sampled adults and their 552 doctors, which found that middle class patients were ‘both more critical and better served’ (Hart 1971:4); there were three times as many middle class patients who were ‘critical of the fullness of explanations’ given to them about their illness; arguing that as it is unlikely that they actually received less explanation than ‘working-class’ patients, this suggests that in fact they ‘expected, sometimes demanded, and usually received much more’ (Hart, 1971:5). As well as the middle classes expecting and demanding more from the health service, they are also likely to have the best GPs, according to the same study; Hart concludes this to show that doctors most able to choose where they work (and thereby likely to be better) tend to opt to work in more affluent areas, making it unlikely to ‘distribute the doctors with highest morale to the places where that morale is most needed’ (Hart, 1971:5). Hart notes that the problem of GP recruitment to poorer areas is worsened by the overrepresentation of ‘professional families’ in medical students (Hart, 1971:5) as they would lack the loyalty to disadvantaged areas that a ‘working class’ doctor might have. All this results in a accumulation of superiority in more affluent (and thereby usually more healthy) areas, as Hart describes: ‘the better-endowed, better-equipped, better-staffed areas of the service draw to themselves more and better staff, and more and better equipment, and their superiority is compounded ‘ (Hart, 1971:5). The ‘morale’ of the doctors in disadvantaged areas is then further weakened by the stress caused by expanding lists, (Hart observes that alcoholism ‘is an evident if unrecorded occupational hazard among those doctors’), presumably also affecting the quality of their work (Hart, 1971:6). Hart gives a useful summary of his ‘Inverse Care Law’:

In areas with most sickness and death, general practitioners have more work, larger lists, less hospital support, and inherit more clinically ineffective traditions of consultation, than in the healthiest areas; and hospital doctors shoulder heavier case-loads with less staff and equipment, more obsolete buildings, and suffer recurrent crises in the availability of beds and replacement staff. These trends can be summed up as the Inverse Care Law: that the availability of good medical care tends to vary inversely with the need of the population served.

(Hart, 1971:12).

Though Hart’s original writing does not provide a hard base of evidence in support of the theory he proposes, and has been described more as a ‘polemic describing the effect of market forces on healthcare’ (Watt, 2002:253), since 1971 much evidence has been collected in favour of the inverse relationship of healthcare, to the point where the ‘Inverse Care Law’ has even been said to have become ‘conventional wisdom’ (Asthana et al, 2008:720). As is evident from the selection of studies discussed in this literature review, a lot of the studies which provide support for his theory tend to be in relation to specific conditions, rather than overall quality of healthcare for all conditions; whilst this may indicate a need for more research to be done to test the validity of the Inverse Care Law overall, I would argue that the variety of specific cases the Inverse Care Law has been found to affect, is itself suggestive of the pervasive nature of the ‘law’ – that evidence of the Inverse Care Law is found in relation to the recognition and treatment of depression, coronary heart disease and health promotion clinics, amongst other specific cases could perhaps be demonstrative of the continuing relevance of the theory .

Whilst the original theory by Hart focuses on GP and resource distribution, in the past thirty-eight years the term ‘Inverse Care Law’ has also been used to describe how those in poorer areas are also disadvantaged in terms of access, consultation length, quality of service, likelihood of diagnosis, referrals to specialists or secondary and tertiary services, waiting time, health promotion clinics and patient enablement and more, despite higher rates of comorbidity, psychological distress and chronic illness. In this study the ‘Inverse Care Law’ is taken to meanany way in which those who need more care, receive less, or receive care of a lesser quality. Whilst there is a vast array of studies concerned with the Inverse Care Law, a selection of five recent studies from the UK will be considered in this literature review; in evaluating these studies I will demonstrate that the evidence shows that the Inverse Care Law holds true today and suggest that this may stem from GP-patient relationships in the context of socio-economic class, rather than the deprivation of the practice’s area.

The Inverse Care Law and Waiting Time and Classification Type for Cardiac Surgery

Recognising that it has already been established that those from lower socio-economic backgrounds are firstly more likely to develop coronary heart disease and die from it, and secondly (despite this) less likely to be investigated for this disease or referred on for surgery following diagnosis, Pell et al (2000) conducted a retrospective study to investigate whether socio-economically deprived patients are further disadvantaged by considering whether there was any association between patients’ socio-economic status and the priority given to them once referred for cardiac surgery. Participants comprised of 26,642 patients waiting for cardiac surgery in Scotland between 1 January 1986 and 31 December 1997 (Pell et al, 2000:15). Multivariate logistic regression analysis was used to distinguish an association between deprivation and classification of urgency and multivariate linear regression analysis was employed to discover any association between deprivation and waiting time (in both cases allowing for age, sex and type of operation) (Pell et al, 2000:15). It was found that as mean waiting time for surgery increased in line with deprivation, patients in the most deprived categories (6 and 7) waited roughly three weeks longer for surgery than the least deprived (category 1) (Pell et al, 2000:16). It was also found that deprived patients were less likely to have their operations classified as urgent compared to the more affluent patients, suggested as the primary reason for the difference in waiting time (Pell et al, 2000:16/17).

This study builds on previous findings and uncovers further inequalities in healthcare in relation to coronary heart disease, providing more evidence in favour of the Inverse Care Law; Hart himself has described the study as ‘representative of the best “Inverse Care Law literature”’, providing the empirical evidence that his original paper lacked (Hart, 2000:18). However, it is not without its limitations; one of these limitations is recognised in the study itself, that the dataset does not include information on the ‘severity of cardiac disease’ and the ‘presence of comorbidity’; this means that there is no way of determining whether the difference in the length of waiting time actually reflects clinical need rather than a socio-economic bias (Pell et al, 2000:17).

Another issue to be wary of is that the data used starts from 1986 and even the most recent figures will be over ten years old. Since this data was recorded there will have been numerous health care initiatives and changes in policy which bring the validity of these results into question. Though perhaps outdated this study should not be disregarded as it alerts us to further ways in which the Inverse Care Law can be seen to be in effect.

The Inverse Care Law and the Diagnosis and Treatment of Depression in Primary Care

Whilst health as a whole tends to follow a social gradient, mental health has been found to have a particularly strong link with deprivation and inequality (Rogers and Pilgrim, 2005:47). Chew-Graham et al studied the attitudes that GPs held towards the management of patients with depression, comparing those from deprived and affluent areas (Chew-Graham et al, 2002:632). They collected qualitative data from semi-structured interviews of the two groups of GPs and compared the verbatim transcripts until thematic categories were identified; agreement on interpretation of the data was then reached through discussion between all authors (Chew-Graham et al, 2002:633). It was found that whilst GPs from affluent areas perceived depression as ‘a treatable illness’ and ‘rewarding work’, GPs from inner-city areas saw the on-going management of depressed patients as an ‘interactional problem’ (Chew-Graham, 2002:632). As diagnosis of depression requires the GP to distinguish between a natural reaction to environment or events and an actual illness, it was concluded in the study that for patients living in deprived environments ‘the problems, and therefore the depression are seen to be insoluble’, one GP even stated ‘living in crap surroundings…is a potent cause of depression’ and another admitting ‘yes, I think a lot of depression is circumstantial’ (Chew-Graham, 2002:632/3).

Identifying environment as a common cause of depression is certainly defensible, however the pessimistic views of doctors in deprived areas further hinder the diagnosis and treatment of such vulnerable patients (Chew-Graham et al, 2002:636). It was found that some doctors even ‘recognized their own reluctance to recognize and respond to such patients in depth because of the much wider structural and social factors’ (Chew-Graham et al, 2002:635), whilst GPs from more affluent areas were not only more positive about treating depression but also optimistic about ‘talking therapies’ and their likely success (though it was clear some of this care was received privately) (Chew-Graham et al, 2002:635). This again serves to demonstrate that those in more need of healthcare, in this case treatment for depression, are less likely to receive it or likely to receive a poorer quality of care. Not only is socio-economic deprivation associated with a ‘higher prevalence of psychological distress’ but also with shorter consultations and this is if it is diagnosed in the first place (Chew-Graham et al, 2002:633, 636). As explained by Stirling et al (2001) the importance of consultation length should not be under-estimated as a further problem in mental health care; not only was it found the consultation length increased with greater affluence, but recognition of psychological distress was greater in longer consultations: a ‘50% increase in consultation length associated with 32% increase in recognition’(Stirling et al, 2001:456).

In terms of the merits and drawbacks of the study by Chew-Graham et al, they only took a sample from the North West of England, which one would expect to be the most deprived and disadvantaged in terms of health; perhaps it would have been more representative to compare practices from different areas of the country. More importantly the sample of GPs was extremely small (only 35 GPs were interviewed) and unbalanced as there were 22 GPs from inner-city areas and only 13 from more affluent areas. The two groups were consulted a year apart from each other (the first in May 2000 and the second in May 2001), making it an unfair comparison. However overall the study is still particularly valuable, not only because due to the strong social patterning of depression the management of depression deserves to be explored in its own right in relation to the Inverse Care Law, but also because it highlights the importance of GPs’ views and how this affects the diagnosis and management of depression; this suggests it is not only a case of investing more resources into healthcare in poor areas in order to combat the Inverse Care Law, the attitudes of doctors themselves needs to be considered.

The Inverse Care Law and the Availability of Health Promotion Clinics

A study by S J Gillam explored the possible relationship between the provision of health promotion clinics and indicators of health need within the practice population (Gillam, 1992:54). Whilst it was found that there was ‘no direct correlation between the number of health promotion clinics run and the measures of need’, it was found that practices receiving deprivation payments as well as practices whose standardised mortality ratio was greater than 100 were less likely to be offering health promotion clinics (Gillam, 1992:55). This has been put down to the fact that most single-handed practitioners are located in deprived and ‘historically unhealthy wards’, as well as suffering lack of time and lack of support staff to make these clinics possible (Gillam, 1992:54/5). This invites doubt as to whether health promotion clinics really reach those who need them the most, Gillam maintaining that ‘If effective, health promotion clinics will have tended to benefit populations in Bedfordshire at lower risk of ill-health’ (Gillam, 1992:54). This Inverse Care Law also applies to check-ups: ‘Within practices, patients at greater risk of ill health, for example those in social classes 4 and 5, are less easily persuaded to attend for health checks’ (Gillam, 1992:54). These findings echo those of the Acheson Report, which describes the ‘Inverse Prevention Law’: that ‘Communities most at risk of ill health tend to experience the least satisfactory access to the full range of preventive services’ such as cancer screening, immunisation programmes and health promotion (Acheson, 1998).

There are of course methodological limitations: ward standardized mortality ratios were used to assign levels of need to practices, yet these ratios do not necessarily refer to the current health status of the practice population (Gillam, 1992:55). Also practices’ receipt of deprivation payments is not necessarily an accurate reflection of their socio-economic context – these payments are based on the ‘Jarman index’ as a measure of deprivation which is of questionable validity (Gillam, 1992:54). This study is important however, in exposing the scope of the Inverse Care Law – it is not just in the likelihood of diagnosis or quality of treatment people receive that healthcare is found to be inequitable, but before these stages of illness are even reached, those with more need miss out on such services that could prevent (or at least lead to early detection of) illnesses.

The Inverse Care Law in Clinical Primary Care

Motivated by the lack of research on how the Inverse Care Law operates, Stewart Mercer and Graham Watt carried out a questionnaire study on 3,044 NHS patients attending 26 general practitioners, 16 of which were in the most deprived areas and 10 of which were in the least deprived areas of West Scotland (Mercer and Watt, 2007:503). Results were analysed in SPSS and unsurprisingly it was found that patients from the more deprived areas ‘had a greater number of psychological problems, more long-term illness, more multimorbidity, and more chronic health problems’ (Mercer and Watt, 2007:503). Interestingly it was found that for patients in deprived areas access to appointments took longer, satisfaction was ‘significantly’ lower, whilst patients had more problems to discuss, (especially of a psychosocial nature), consultations were shorter and satisfaction with consultation length was considerably lower,  GP stress was higher and patient enablement (in dealing with psychosocial problems) was lower. It was concluded that these were all some of the ways that the Inverse Care Law continues to operate within the NHS (Mercer and Watt, 2007:503).

It is noted in the study itself that this was carried out before the introduction of the 48 hour access target set by the UK Government, which may have had a significant effect on access as well as patient satisfaction with access (Mercer and Watt, 2007:508). Also it is worth mentioning that the recruitment rate of general practices was only 37% which brings into question the representativeness of the sample and thereby the validity of the findings. Furthermore, that the sample was only taken from West Scotland, brings more doubt to the representativeness; it was commented by Watt himself in a recent report of a special meeting of practitioners from deprived areas in Scotland that practices in this area are in fact uniquely characterised by ‘high quality (as measured by the Quality of Outcomes Framework), high morale (as demonstrated by involvement in additional professional activities) and high commitment to improving services for patients’ (evident from the discussions at the meeting) (Watt, 2009:12). However, if this description holds true then if anything this study can be said to possibly underestimate the effects of the Inverse Care Law in primary care.

Not only is this study the most recent of those discussed but it is also comprehensive; in analysing a more extensive range of ways in which the Inverse Care Law can be said to affect health care it provides the strongest support for the argument that the Inverse Care Law is still relevant today.

Evidence Against the Inverse Care Law in Provision of Care for Coronary Heart Disease

Whilst the studies discussed so far are characteristic of the majority of studies on the Inverse Care Law it is important to consider research findings against the Inverse Care Law. Using data from the UK Quality of Outcomes Framework, (a voluntary scheme set up to encourage good practice and quality of service amongst doctors, by offering financial rewards for points achieved from a range of good healthcare indicators (NICE, 2010; The NHS Information Centre, 2010), Strong, Maheswaran and Radford present an ecological study, testing previous findings that the provision of healthcare for patients with coronary heart disease is unequal (Strong et al, 2006:39). Whilst it was found that coronary heart disease was more prevalent in deprived practices, contrary to previous findings and predictions of the Inverse Care Law, they found no evidence of inequality in healthcare for coronary heart disease, in fact the only quality of care indicator that did correlate with deprivation was in the case of smoking status and this showed a positive relationship, suggesting the possibility of better care in deprived areas for this condition (Strong et al, 2006:39-41). However, as the findings of this study appear to be the exception rather than the rule more evidence needs to be collected in support of these conclusions, especially considering that the Quality of Outcomes Framework appears to be a controversial measure of the quality of healthcare provided (Guthrie et al, 2006).

Summary of the Studies and Literature

Whilst one study discussed has found evidence contradictory to the Inverse Care Law the overall consensus of the studies is that the Inverse Care Law still exists today, whether it is in the case of diagnosis and management of depression, availability of health promotion clinics, access and consultation length or waiting time for surgery. As well as further studies there is much literature that supports these findings, such as Nick Seddon’s book Quite Like Heaven? Options for the NHS in a consumer age (2007). Drawing on a range of studies Seddon argues that it has ‘repeatedly and conclusively been demonstrated, that the poor and ethnic minorities are significantly disadvantaged in their access to, and use of, the NHS’ (Seddon, 2007:10). As well as issues already raised by the studies discussed, Seddon adds to the significance of the association between socio-economic deprivation and longer waiting times; he reasons that longer waiting times are not merely an inconvenience but stresses that the waiting itself can actually make you ill, referring to one study that found 21 per cent of lung cancer patients to be unsuitable for curative treatment following their wait for radiotherapy (Seddon, 2007:57). Seddon also discusses a study on total elective hip replacement which shows a clear mismatch between those who showed greater prevalence and severity of hip disease and those who received surgery (Seddon, 2007:82). In emphasising the importance of this issue of healthcare inequity, Seddon quotes the estimated number of avoidable deaths in relation to one study of emergency procedure on fractured neck of femur (Seddon, 2007:84).

Beyond problems of access to primary care, in relation to secondary and tertiary services Seddon alludes to the problem of lower referral rates for lower-socioeconomic groups (Seddon, 2007:87). An important point made in the book which relates to all of the studies mentioned is that Britain currently has what he refers to as a ‘two-tier health care system’; as private healthcare utilisation is concentrated among areas of higher socioeconomic class and there is little data available on this, all these studies can be said to be actually underestimating socioeconomic inequalities in healthcare (Seddon, 2007:10, 83).

Whilst the literature discussed supports Hart’s case for the existence of the Inverse Care Law there are two reasons why it is less convincing of the second part of his theory (that it is simply due to market forces (Tudor-Hart, 2000:19)). Firstly that this relationship between need and health services continues despite numerous policies put in place since 1971 which have actively sought to invest extra resources and money into poorer areas, for example the Allocation of Resources to English Areas (Sutton et al, 2002) which sought to calculate and distribute resources to areas based on need.

Secondly a lot of the literature considered so far has suggested that a possible source of the Inverse Care Law actually lies within the dynamics of the GP-patient relationship which would suggest that an individual’s socioeconomic status is much more important in determining the type of service they will receive rather than the overall deprivation of the area in which their health services are situated. For example the study of depression by Chew-Graham et al highlighted the significance of GP attitudes and bias on the process of diagnosis and treatment (2002). Similarly the study by Pell et al (2000) that found deprived patients were less likely to have their cardiac surgery classified as urgent and consequently wait longer, also identifies the importance of the GP’s role in health care inequities. Seddon comments on the difference in referral rates, again at the hands of the doctor (2007:87) and reinforcing the literature already discussed, a comprehensive analysis of both macro and micro studies of health care equity by Le Grand et al concludes that the GP-patient relationship is the source of the problem: access to specialist services are ‘controlled’ by GPs (Le Grand et al, 2007:108). Le Grand et al suggest there are two potentially influential aspects to this relationship:  ‘Firstly, GPs may find it easier to deal with more affluent people and to respond to their concerns; secondly, by virtue of their education, articulacy and general self-confidence, the better-off may simply be better at persuading GPs’ of their need for specialist services (2007:108). In other words, a ‘major’ reason for the inequity in health care services may be that the middle classes are more likely to have ‘a ‘voice’ that is more likely to be heard, understood, and indeed even empathized with, by the professionals concerned’ (Le Grand, 2007:108). Overall the interaction between socioeconomic class and the GP-patient relationship may play a serious role in the inequity of health services.

Implications for Further Research

It is clear from the literature reviewed that the current consensus is that the Inverse Care Law still plays a significant role in the NHS. The majority of studies focus on the Inverse Care Law in relation to one particular condition and a lot of the samples are based in Scotland and not representative of the whole of the UK. Moreover, considering there have been recent changes to healthcare policies and initiatives, including the implementation of the Qualities and Outcomes Framework, a lot of this data is already outdated. As well as the need for up-to-date research, the literature reviewed has cast doubt on the second part of Hart’s theory, that the problem lies in market forces, indicating rather that it lies in the GP-patient relationship, though this has not been specifically tested.  Further research is therefore needed to not only assess whether the Inverse Care Law is still relevant to the NHS following recent policy changes, but also to test whether it is the economic context of the health service or an individual’s socioeconomic class that has more effect on the type of service they receive; essentially having found overwhelming support for the first part of Hart’s theory, the often overlooked second part of the theory requires testing. This is important to investigate because if the problem does stem from GP-patient relationships and the clashing of social class then it suggests that rather than redirecting resources to solve the problem, it would be more beneficial to educate GPs to make them aware and reflective of these issues, as well as specifically target and encourage those from lower socioeconomic backgrounds to use the health services; the implications for policy are therefore great.