Main Findings
We have developed a novel and user-friendly tool wherein
comprehensiveness of outcome reporting in obstetric clinical trials can
be graphically represented as a heatmap. This tool will enable
trialists, systematic reviewers, and clinicians to critically assess
outcome selection in obstetric trials and use this information to
contextualize findings of studies and meta-analyses.
Ensuring comprehensiveness of outcome reporting is vital to designing a
clinical trial, and its assessment should be integral to conducting a
thorough systematic review of clinical trials, in any area of medicine.
In obstetrics, where the implications of decisions made during pregnancy
can have life-long consequences to both mother and fetus, in regard to
life, life-expectancy, and resource-use, it is particularly important
that conclusions pertaining to the benefits of an intervention are based
on a holistic set of outcomes. Although obstetrical interventions can
impact both individuals, researchers have drawn attention to a lack in
reporting of fetal-neonatal outcomes,23 and more
recently, to the importance of considering long-term maternal outcomes,
such as cardiovascular mortality and morbidity from prolonging
pregnancies complicated with hypertensive disorders of pregnancy, to
improve neonatal outcomes.24 Drawing conclusions based
exclusively on outcomes related to one individual may neglect important
negative outcomes in the other.
The World Health Organization mandates that “choosing the most
important outcome is critical to producing a useful guideline”,
acknowledging that “different groups value outcomes
differently”.25 A priority-setting exercise that
involved 48 clinical trial directors, identified “choosing appropriate
outcomes to measure” among their top three priorities, while designing
trials.26 The focus of contemporary medicine goes
beyond avoiding mortality, to preventing morbidity and improving the
quality-of-life.27, 28 Comprehensive selection of
outcomes related to these goals is challenging with current financial
pressures and practical constraints. Yet, it should not be acceptable
for trialists to draw conclusions on effectiveness or efficacy based on
a limited set of outcomes that do not ‘improve health’ or ‘prevent
infirmity’, in the holistic sense of these terms, especially when
reporting these outcomes is feasible. Studying outcomes that are not
relevant to patient care contributes to significant, and avoidable,
waste of health research dollars and continues to force healthcare
professionals to make decisions based on literature that is less than
ideal in regard to transparency.
Published trials seem to place greater emphasis on
physiological/clinical outcomes, in favour over other often neglected
aspects of health such as emotional well-being, patient satisfaction,
and resource costs. A systematic review that analyzed 16525 outcomes
from 3515 different Cochrane reviews, showed that 83% of reported
outcomes were categorized as physiological, while less than a quarter
(24%) measured functional impact and quality of
life.3 This is also true of obstetric conditions such
as pregnancy in obesity and cardiac disease, wherein published studies
are found to be lacking in their inclusion of important patient-centric
outcomes.5-9 This barrier to translation is further
magnified when trying to interpret evidence across studies, due to the
vast variation in outcome selection and measurement.8,
9, 29
Other criticisms with the choice of outcomes include the inappropriate
use intermediate outcomes as surrogate outcomes,30 the
lack of patient perspective when choosing outcomes, under-reporting of
adverse events,11 and the use of poorly selected
components within composite endpoints.31 Ultimately,
many of these gaps originate from a lack of comprehensive outcome
selection, the very issue our COR Tool has been designed to mitigate.