Johns Hopkins Nursing Evidence-Based Practice Thrid Edition: Model and Guidelines

(^26) Johns Hopkins Nursing Evidence-Based Practice: Model and Guidelines, Third Edition
Research evidence has a higher level rating than nonresearch evidence, in particu-
lar when the scientific evidence is of high quality. EBP team members apply criti-
cal thinking skills when appraising scientific research by focusing on two major
components: study design (usually classified as experimental, quasi-experimental,
nonexperimental, qualitative, and mixed-methods) and study quality (evaluation
of study methods and procedures). When evaluating the summary of overall evi-
dence, teams consider four major components: study design, quality, consistency
(similarities in the size and/or direction of estimated effects across studies), and
applicability (the extent to which subjects, interventions, and outcome measures
are similar to those of interest) (GRADE Working Group, 2004). The various
types of research evidence and their associated levels of evidential strength are
further explored in Chapter 6.
Because of the complex human and environmental context of patient care, re-
search evidence alone is not sufficient to inform practice. In many instances,
scientific evidence either does not exist or is insufficient to shape nursing practice
for the individual patient, population, or system. Nonresearch evidence also is
needed to inform nursing knowledge and generally includes summaries of re-
search evidence reports, expert opinion, practitioner experience and expertise,
patient experience, and human/organizational experience. Clinical appraisal of
the strength of nonresearch evidence is not as well established as is that for sci-
entific evidence and is therefore more challenging. Because nonresearch evidence
is thought to be outside the realm of science and thus less meaningful, appraisal
methods have rarely been considered. The various types of nonresearch evidence
are discussed in Chapter 7.
The development of any EBP skill set is an evolutionary process. Critical thinking
is thought by many to be a lifelong process requiring self-awareness, knowledge,
and practice (Brunt, 2005). The JHNEBP model uses a broadly defined quality
rating scale to provide structure for the nurse reviewer, yet allows for the appli-
cation of critical thinking skills specific to the knowledge and experience of the
team reviewing the evidence. This scale accommodates qualitative judgments re-
lated to both scientific and nonresearch evidence.