The requirements of the role of purchasing authorities (whether health authorities or primary care groups or others) has the following effects:
First, need for health care must be distinguished from the need for health. The need for health care is much more specific than the need for health. The latter concerns who is needy in general terms, and can be measured by morbidity, deprivation and socio-demographic measures. Health problems with no realistic treatments are included here. But these measures alone have little to say that helps the specification of health care services, except perhaps in distinguishing relative levels of need between large areas. The need for health care is much more specific and is now widely accepted to mean the population's ability to benefit from health care.(21-23) It depends on the potential of preventive or treatment services to remedy health problems.
Second, needs assessment for practical purchasing requires a useable level of detail for those who will subsequently specify services. The definition, the population's ability to benefit from health care, leaves open the level of detail at which health care is defined. However, it is important not to specify needs so generally that different populations and interventions cannot be distinguished, nor to specify needs in so much detail that the activity of health care needs becomes overwhelming. A reasonable compromise should be sought.
Third, need is quite different from supply and demand. Put simply, need is what people might benefit from, demand is what people would be willing to pay for in a market or might wish to use in a system of free health care, and supply is what is actually provided. Although this distinction is uncontroversial, the difficulty of measuring need makes it tempting to measure supply and demand as surrogates for need. This is complicated by the price being zero for services free at the point of use. Supply and demand are not tempered by each other as they might be in a market with a price mechanism. Furthermore supply is the consequence of historical patterns mixed with the consequences of political pressure for change. It is clearly misleading to measure the existing service provision as though it were an indicator for need. Similarly, the measurement of waiting lists, reflecting as they do demand mediated by doctor as agent, is also misleading. Figure 1 illustrates how need, demand and supply might overlap or differ.(9) It shows eight fields of services divided into (i) those for which there is a need but no demand and supply, (ii) those for which there is a demand but no need or supply, (iii) those for which there is a supply but no need or demand, and then (iv-vii) the various degrees of overlap.
The diagram indicates where work is required not just in assessing health care needs, but also in attempting to make the three circles of need, demand and supply more congruent. This includes demand management and changing supply as well as better definition of need. Demand management may involve curtailing it where it is inappropriate (areas 2 and 5 in Figure 1), stimulating it (areas 1 and 6), or coping better with it (area 4).(24) Varied mechanisms with which demand can be influenced include: the accessibility and organisation of services, the provision of health information, education, and financial incentives.(25-27) Supply changes may require subtle mechanisms not easily captured in service agreements. Where the cause of the mis-match between supply and need is clinical practice, effective strategies to promote behaviour change among professionals are required. These can include educational outreach visits, reminders, interactive educational meetings, audit and feedback, use of local opinion leaders, local consensus processes and patient mediated interventions.(28) Even need can be shifted somewhat, given that research programmes can be altered, with new findings on pathology and degrees of benefit which matter to patients, and the identification of forms of health care that are effective.
Fourth, needs are probably best explored basing the assessment on disease groups. The logic is that a need arises when there is a lesion rather than when a person has reached a certain age, belongs to an ethnic sub-group, or because a particular service is provided. However, this is not an absolute rule. The ability to benefit from health care can be assessed at the level of the sub-population who may benefit from a particular intervention (provided competing interventions are considered). Such units can be reassembled around particular services, or population sub-groups such as demographic minorities. Some chapters in this series are therefore oriented around services such as family planning, and around mixed groups such as people with learning disabilities. In primary health care needs assessment it is often argued that a good starting point is around a particular intervention.(29)
Fifth, often the key element of health care needs assessment is the measurement of the effectiveness of interventions. The evidence-based medicine and evidence-based health care movements are relatively recent and it remains the case that clear information on effectiveness is often absent in service planning. But it cannot be argued that ineffective services are needed. Therefore, where effectiveness is in doubt, a first step is a gathering of effectiveness information.
Sixth, health care needs assessment is only ever artificially divorced from setting priorities in health care. Some "needs assessors" would prefer not to acknowledge resource shortages, and argue that all needs should be met. The untenability of this view as the proliferation of new potentially effective health care technologies continues apace becomes ever clearer. Needs assessment can be integral to prioritisation, because it is only a short step from need as the ability to benefit from health care to a utilitarian view of relative need as the relative ability to benefit per unit cost. This is not to deny an exploratory phase of needs assessment, a sort of scanning exercise, before such hard calculations are made, nor to deny that precision in quantifying priorities is very elusive.
Seventh, it is worth noting the distinctions between individual need and population need. Population need can be viewed as the sum of individuals' need. But the viability of this assumption is dependent on how the individual needs assessment is undertaken. If it strays into an assessment of demand, or it is unconcerned with proven ability to benefit, it is likely to distort assessed population needs. Clearly there are differences between the view of a carer dealing with (assessing the needs of) an individual, and a planner looking at a population. The former is likely to be a strong advocate for the patient, take no account of people who are in need but do not come to the clinic, and (as regards relative need) take little account of costs. The circumstances in which individual needs assessment is a practical means of assessing health care needs at a population level are those in which individual patients are few, highly costly, very heterogeneous and countable (i.e. not hidden from the view of routine data).
Eighth, one can also distinguish between needs for (public sector) services other than health care and services for health care. "Benefit" in the former tends to be more open-ended. In health care, increasing inputs of care can be associated with zero benefit or negative benefit (harm). The limits of benefit are not so clear with education, housing or transport (although even here diminishing returns and even negative benefit is evident sometimes). However, other public sector services have an impact on health, and with a collaborative approach to health care needs assessment across different sectors, the relative contribution of different investment (relative needs assessment) will be important.
Ninth, needs assessment itself incurs costs. This means that short-cuts can be necessary, and indeed it is argued below that surrogate measures (making comparisons and taking a corporate view) have a valid place in health care needs assessment.
Aim of health care needs assessment
The overall aim of health care needs assessment is to provide information to plan, negotiate and change services for the better and to improve health in other ways. In other words the assessment can be done with an eye to any activities which have an impact on health, whether directly in the hands of health services or not. The working definition of health care need as the population's ability to benefit from health care reflects this (and can be expanded to cover "services" more widely).
It is worth noting that each element of the definition is important:
Table 1: The need for health care: the population's ability to benefit from health care
The population's ability to benefit from health care equals the aggregate of individuals' ability to benefit. For most health problems this will be deducible from epidemiological data, rather than from clinical records.
The ability to benefit does not mean that every outcome is guaranteed to be favourable, but rather that need implies potential benefit which on average is effective.
The benefit is not just a question of clinical status, but can include reassurance, supportive care and the relief of carers.* Many individual health problems, especially infectious diseases and long-term disabilities, have a social impact via multiple knock-on effects or via a burden to families and carers. Consequently, the list of beneficiaries of care can extend beyond the patient.
Health care includes not just treatment, but also prevention, diagnosis, continuing care, rehabilitation, and palliative care.
*Diagnosis and reassurance constitute an all important component of primary and ambulatory care including accident and emergency services where a high proportion of people may require no more than a negative diagnosis.
Objectives of health care needs assessment
(1) The principal objective of health care needs assessment is to specify services and other activities which impinge on health care. The principal activities involved in health care needs assessment are therefore:
the assessment of incidence and prevalence (how many people need the service/intervention),
the effectiveness and cost-effectiveness of their services (do they confer any benefit, and if so at what cost ie what is the relative benefit), and
the baseline services (changing provision for the better necessitates knowledge of the existing services, both to know which services ought to change and to identify opportunities for the release of resources to enable the change to happen).
These three components - incidence and prevalence, health service effectiveness, and baseline services form the basis of "triangulation" (see Figure 2) whereby health care purchasers and planners can determine the policy directions they wish to pursue. They form the three main elements of the protocol used to structure the needs assessment in subsequent chapters of this series.
There are, however, also other objectives in health care needs assessment which flow from the aim of planning, negotiating and changing services for the better.
(2) Improving the spatial allocation of resources. This was the principal objective of national needs assessment in the UK at the time of the Resource Allocation Working Party and before, right up to the 1990 NHS reforms. It seems a reasonable supposition that if broadly equal populations are to receive services, the most efficient deployment of services will be to give them broadly equal resources. This supposition works well at a macro level, but weakens as the scale gets smaller - because the chances of small areas having equal needs, other things being equal, reduces. And given that resources will continue to be allocated between sub-national units, spatial allocation continues to be important.
(3) Thirdly, target efficiency (the accurate targeting of resources to those in need) is often a central activity of needs assessors. Strictly the measurement of target efficiency is the measurement of whether or not, having assessed needs, resources have been appropriately directed. In this sense, target efficiency is related to audit. But, it is always important to know whether, having defined the need, those who get a service need it, and those who need it get it.
A number of new objectives for health care needs assessment have been suggested following the expansion of needs assessment into general practice. They include (in various guises) the three above, but to these can be added:
(4) The gathering of general intelligence to get a perspective on population health and population health needs. This objective is, of course, important not just for new primary care needs assessors, and in many respects can be considered the first stage of needs assessment, rather than a separate objective.
(5) Fifth, the objective of health care needs assessment to stimulate the involvement and ownership of different players in the process has been noted. The more members of the primary care team and others are involved in the assessment, the more likely attention will be paid to the findings of the activity. Again, this argument could be extended to needs assessment undertaken outside primary care.
Scales of needs assessment
Although the aim of needs assessment remains the same at all scales, the principal objectives and the process are likely to vary according to the scale of assessment: these can be summarised as follows:
- National (circa 50 million)
- Regional (circa 5 million)
- Local Authority/health authority (circa 500, 000)
- Primary Care Group (circa 50, 000 to 100, 000)
- Individual General Practice (circa 5000 to 10, 000).
National needs assessment
There are many national health care concerns. National needs assessment is necessary for areas of legislative change. These include modifications of health services - particularly including elements of the public health agenda such as seat-belt and tobacco control legislation. It also applies to elements of planning affecting the national economy - including, for example, very large capital investments - and to politically and media sensitive areas such as those issues raised by "post-code prescribing". Indeed, part of the rationale for the establishment of the UK's National Institute for Clinical Excellence was to end 'unacceptable geographical variations in care'.(30) National needs assessment is also the level for the assessment of spatial equity between large sub-national regions.
Regional health care needs assessment
Despite both a policy of centralisation and a wish to delegate planning to a unitary level of health authority below that of the region, regional planning has been remarkably durable. There are certain services for which the region is an obvious scale of activity. These concern not just such large spatial issues such as fluoridation, but also for medical specialties where provision needs to be at the scale of a population of several million. It is also a useful scale for co-operation between health authorities and local government - especially at a time of regional devolution.
Spatial equity, specific service planning (sum of) and target efficiency are all relevant at the regional level.
Health authority/local authority needs assessment
This is the traditional level of health care needs assessment. There is, however, a big difference between the traditional agenda of health authorities and of local authorities: the former with a tradition of technical planning - increasingly for effective and efficient services and the latter with a tradition of working with the politics of local democracy. The scope of the services provided by both differs as well, and the combined agenda addressing principally service specification, but also target efficiency, is very large and will need to be highly selective.
Primary care group needs assessment
In the UK planning at this level is relatively recent. It is likely to have elements of both health authority scale planning, and of individual practitioner planning. This has both opportunities for service specification, and of individual clinical insights, and can make use of the, potentially fertile, practice register data available at individual practitioner level.
Individual practitioner needs assessment
The individual practitioner has long had much promise as a needs assessor, given his/her access to case registers, his/her role as a consumer of secondary care, and therefore at arm's length from it, and his/her feel for a patient perspective on service. However, these advantages are tempered by the difficulties of needs assessment at this level, including the conflict of needs assessment with general practitioners' business interests, and the ease with which practitioners can ignore unseen patients.
Needs assessment activities at this scale can only include service specification for the most prevalent of diseases, and of primary care services; but target efficiency (audit) can be reviewed intensely.
Different types of health care needs assessor/"assessments"
It should also be recognised that technical needs assessors do not have a monopoly on the words "needs assessment". Those who might consider themselves needs assessors could include:
- Politicians - both national and local,
- Clinicians - both generalist and specialist
- Patients, as well as
The different perspectives of these assessors will obviously influence the characteristics of the assessment. In theory all can undertake valid assessments but it is worth examining any product against understood criteria.
The following questions have been identified in judging assessments:(31)
1. Is there a clear context of allocating scarce resources? Needs assessments that fail to acknowledge resource limitations are common, but are of restricted value to health care commissioners. This can be a problem with individual clinical needs assessment, which can put great pressure on health budgets and squeeze the care available to patients with weak advocates. Some population approaches also fail to acknowledge resources used. This is a difficulty, for example, with specialty-specific documents recommending levels of service within a single specialty.
2. Is the needs assessment about priority setting within the context of a variety of competing needs or is it about advocacy for a single group or individual? This is closely related to the resource context question. Specialty-specific documents, client group surveys and even policy directives which focus on single groups often represent advocacy rather than balanced contributions to priority setting. Surveys about, for example, the needs of a particular ethnic minority are of limited help in guiding health care planners unless seen in the context of equivalent surveys of other groups. Policy recommendations based on lobbying would be much more prone to distorting resource use than policy directives based on research.
3. Is the needs assessment exploratory or definitive? Some approaches to needs assessment are exploratory in that they highlight undefined or under-enumerated problems. This is particularly true of lifestyle surveys that estimate the size of risk groups such as alcohol abusers or teenage smokers. Exploratory surveys are best thought of as just a first stage in a more specific needs assessment process.
4. Is the determination of the most important needs expert or participatory? Technocratic needs assessment tends preferentially to be expert, although the Oregon experience demonstrates that participatory approaches and expert ones can be merged. Expert approaches seek to be as objective as possible, although objectivity soon reaches its limits.
Approaches to needs assessment
The approach to needs assessment based on the triangulation of incidence and prevalence, effectiveness and cost effectiveness, and existing services (Figure 2) we have labelled 'the epidemiological approach to needs assessment'. This method is described more fully below.
Needs assessment will usually aim to make incremental changes to existing services. The epidemiological approach to needs assessment can usefully be supplemented by other tools. Indeed, in view of the shortage of information both on effectiveness and on prevalence, and because of the size of the task of reviewing and applying such information even when it is available, health care purchasers have tended to use two other simple methods: the 'comparative' and the 'corporate' approach.(22)
Comparative approach to needs assessment
The comparative approach to needs assessment contrasts the services received by the population in one area with those elsewhere. Comparisons can be powerful tools for investigating health services, especially in the context of capitation-based funding. Variations in costs and service use may be appropriate depending on local circumstances, but with capitation funding of health care, gross departures from the mean require justification. The literature on differential rates of surgery for example shows that the more loosely defined the clinical indications are for a particular problem, the more likely considerations other than need and benefit are to influence levels of activity undertaken.(32),(33)
Comparative service provision should take account of local population characteristics including demographic and morbidity data, such as provided by the English Public Health Common Data Set.(34) To the extent that such sources are beginning to provide detailed mortality and morbidity information, they may start to act as population outcomes data. The use of such data in this way, however, relies on the assumption that health care is a major determinant of mortality and morbidity, which may not be justified.(35)
The corporate approach to needs assessment is based on the demands, wishes and alternative perspectives of interested parties including professional, political and public views (see Figure 3). While such an approach blurs the difference between need and demand, and between science and vested interest, it also allows scope for managing supply and demand at the same time as assessing need as affected by local circumstances. It would be surprising if important information were not available from those who have been involved in local services over many years. In the National Health Service context, this corporate approach has been widely used, and was encouraged in both the 1989 reforms with its 'local voices',(36) and the emphasis on partnership and collaboration in the 1997 white paper.(8)