Just as treatments for other chronic illnesses change based on new
advances in research and science, so, too, do treatments for substance abuse and mental
disorders, whether occurring separately or co-occurring in a single individual. The
challenge to mental and substance abuse professionals - and to the field as a whole - is
to ensure that the services being provided, in fact, are the most appropriate for the
individual and are the best possible from the perspectives of effectiveness and
appropriateness. Those principles undergird the concept of evidence-based services and
evidence-based practice.
The evidentiary yardstick against which the effectiveness of services
is measured, itself, can vary in precision. Today's "gold standard" evidence-based
practice to determine whether a treatment intervention does more good than harm is the
assessment of research findings from randomized controlled clinical trials, constituting
a rigorous research design (Ley et al., 2000; Sackett et al., 1996). Slightly lower on
the scale - the next best evidentiary base - is the quasi-experimental study, in which
comparison groups are assigned by randomization (Drake, Goldman et al., 2001). Some
researchers believe that findings from open clinical trials (those lacking independent
comparison groups) coupled with expert-based clinical observations are insufficient
findings on which to determine the effectiveness and rigor of a particular practice. Such
researchers believe that only the "gold standard" ensures against the adoption of
practices as evidence-based that are contradicted by later findings of controlled
research (Drake, Goldman et al., 2001).
It is not surprising that many approaches to care for people with
co-occurring substance abuse disorders and mental disorders do not reach the high bar set
by the research community's "gold standard." For that reason, the Institute of Medicine
has adopted a more pragmatic approach. In its report, Crossing the Quality
Chasm: A New Health System for the 21st Century (2000), IOM
embraced a less stringent definition of what constitutes an evidence-based practice,
suggesting it is the integration of three critical elements:
Best research evidence:
clinically relevant research, often from the basic health and medical sciences, but
especially from patient-centered clinical research into the accuracy and precision of
diagnostic tests (including the clinical examination); the power of prognostic markers;
and the efficacy and safety of therapeutic, rehabilitative, and preventive
regimens.
Clinical expertise: the
ability to use clinical skills and past experience to identify and treat each patient's
unique state and diagnosis, to assess the individual risks and benefits of potential
interventions, and to do so within the context of the patient's personal values and
expectations.
Patient values: the
preferences, concerns, and expectations each patient brings to a clinical encounter that
must be integrated into clinical decisions if they are to serve the patient.
The meaning and interpretation of evidence, no matter what kind, is
an essential
and probably continual task. All forms of evidence must be weighed to
determine whether efficacy (evidence of an effect under ideal conditions) or
effectiveness (assessed/evaluated in actual practice) is achieved, and to delineate the
particular conditions under which the approach can reasonably be expected to produce
favorable outcomes (Peterson, 2001).
Many approaches to treating co-occurring disorders that do not meet
strict standards of evidence are nevertheless commonly accepted and believed to be
effective based on the best available research, clinical expertise, individual values,
common sense, and a belief in human dignity. It is incumbent on practitioners to use the
best available approaches.
