Evaluating Patient-Based Outcome Measures - NIHR Health ...

The emergence of patient-based
outcome measures
A number of trends in health care have resulted
in the development and growing use of patientbased
outcome measures to assess matters such as
functional status and health-related QoL (Bergner,
1985; Ebbs et al., 1989). It is increasingly recognised
that traditional biomedically defined outcomes
such as clinical and laboratory measures need
to be complemented by measures that focus
on the patient’s concerns in order to evaluate
interventions and identify more appropriate forms
of health care (Slevin et al., 1988). Interest in
patient-based measures has been fuelled by the
increased importance of chronic conditions,
where the objectives of interventions are to arrest
or reverse decline in function (Byrne, 1992).
In the major areas of health service spending,
particularly in areas such as cancer, cardiovascular,
neurological and musculo–skeletal disease, interventions
aim to alleviate symptoms and restore
function, with major implications for QoL (de Haes
and van Knippenberg, 1985; Fowlie and Berkeley,
1987; Devinsky, 1995). In many new and existing
interventions, increased attention also has to be
given to potentially iatrogenic effects of medical
interventions in areas such as well-being and quality
of life. Patient-based outcome measures provide
a feasible and appropriate method for addressing
the concerns of patients in the context of
controlled clinical trials.
At the same time, increased attention is given to
patients’ preferences and wishes in relation to their
health care (Till et al., 1992). Patients increasingly
expect with good reason to be involved in decisions
about their care and to be given accurate information
to facilitate their involvement (Siegrist and
Junge, 1989). More evidence, and more relevant
evidence, is therefore needed by patients about
how illnesses and their treatments are likely to
affect them.
Continuing difficulties experienced by all
governments and health authorities in finding
financial resources to meet demands on health
care increase pressures for evidence to assess
benefits in relation to costs of health care so
that better use is made of resources. Evidence
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Health Technology Assessment 1998; Vol. 2: No. 14
What are patient-based outcome measures?
is needed of such benefits as perceived by patients,
carers, health care professionals and by society as
a whole (Epstein, 1990; Anonymous, 1991a;
O’Boyle, 1995).
For all these reasons, much greater effort is now
required to assess the impact upon the individual
of illness and treatments by means of accurate
and acceptable measures. An enormous array
of instruments in the form of questionnaires,
interview schedules, rating and assessment forms
has emerged that have in common the objective
of assessing states of health and illness from the
patient’s perspective. Because their purpose is to
assess the impact of health care interventions from
the view-point of the patient, this review refers
collectively to such instruments as patient-based
measures of outcome.
Accompanying the mounting interest in patientbased
measures is an explosion of literature.
One MEDLINE search on QoL revealed 1000
articles (Rosenberg, 1995) and another retrieved
three times as many QoL papers in 1994 as in
1990 (Editorial, 1995). In part, this vast and
rapidly expanding literature reflects a huge growth
in the number of new questionnaires and other
instruments to assess health status and related
concepts. In response to these developments, a
number of volumes have appeared which provide
guides to the different types of instruments, their
content and range of applications (Wilkin et al.,
1993; Bowling, 1995a; McDowell and Newell, 1996;
Spilker, 1996; Bowling, 1997). These volumes
provide an excellent resource for the investigator
wishing to examine the range of instruments
available in, for example, a particular condition
such as cancer, or to assess a particular aspect of
QoL such as social support. From such sources,
the reader can review the range of instruments in
any field and also the history of their development
and use, to date.
There are also now available increasingly clear and
informative guidelines about how to develop and
report the development of patient-based outcome
measures (Sprangers et al., 1993; McDowell and
Jenkinson, 1996) and how such measures should
be used and reported in clinical trials (Staquet
et al., 1996; Fayers et al., 1997).
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