This is the third in a series of six articles describing approaches to and topics for health needs assessment, and how the results can be used effectively

The purpose of needs assessment in health care is to gather the information required to bring about change beneficial to the health of the population. It is generally, but not universally, accepted that this takes place within the context of finite resources.1 “Health gain” can therefore be achieved by reallocating resources as a result of identifying four factors:

• Non-recipients of beneficial healthcare interventions (that is, unmet need);

• Recipients of ineffective health care (and releasing the resources for unmet need);

• Recipients of inefficient health care (and releasing resources for unmet need); and

• Recipients of inappropriate health care (for whom the outcomes could be improved).

The subjects of healthcare needs assessment are the populations and patients who are recipients or potential beneficiaries of health care. Populations, of course, include individual patients. The assessment of individuals' needs may form part of the assessment of a population's needs, but it may be costly and it risks ignoring individuals with needs who do not present themselves for health care. Table 1 shows the circumstances favouring individual needs assessment for planning purposes.

The priority attached to different needs, whether of populations or of individuals, raises philosophical problems. For example, should the principal criterion be the benefit that could potentially be obtained for each individual, or the severity of their presenting condition?2 In other words, should greater priority (a greater assessed need) be attributed to the need for surgery of a patient with early stage colorectal cancer or to the need for hospice care of a terminally ill lung cancer patient? In practice the former, the approach that favours the greater …