INTRODUCTION
Assisted vaginal birth (AVB) is an invasive procedure that, in skilled
hands, can markedly improve maternal and neonatal outcomes arising from
complications in the second stage of labour. Typically, AVB involves the
use of devices such as forceps or ventouse and, more recently, new
devices. Well-designed randomised controlled trials (RCTs) are essential
for assessing the effectiveness of invasive procedures such as AVB,
thereby enabling clinicians to make evidence-based decisions about
whether to introduce them in routine practice. Similarly, high-quality
reporting of RCTs is necessary to ensure that such procedures and
devices are adopted and implemented correctly. However, the design and
conduct of RCTs involving invasive procedures and devices (such as AVB)
can be challenging because of their complexity. Complex interventions
are defined as those with multiple interacting components that can act
independently or interdependently to influence outcomes. This complexity
can create difficulties in establishing how interventions should be
delivered (standardisation) and ascertaining whether they are actually
delivered as intended (adherence) within an RCT. Additional challenges
are that the delivery of complex interventions can be influenced by
clinicians’ skill (expertise). There may also be repeated modifications
of new invasive procedures or devices during the developmental phase,
which may not be reported or accounted for in trial design, that may
influence trial outomes.
With accumulating numbers of reports citing complications associated
with new invasive procedures and devices, expert panels have suggested
that more rigorous clinical evaluation is required through improved RCT
design. The need for methodological rigour has also been acknowledged in
reporting guidance documents such as the Consolidating Standards of
Reporting Trials extension for non-pharmacological treatments
(CONSORT-NPT), which includes invasive procedures and devices such as
those used for AVB. CONSORT-NPT suggests that ‘precise details of the
experimental treatment’, ‘details on whether and how the interventions
were standardised’, ‘details of whether and how adherence of care
providers to the protocol was assessed’, and ‘information about the
expertise of care providers’ should all be described in trial reports.
As well as reducing bias and improving methodological quality, provision
of this information should help to contextualise trial findings, enable
successful interventions to be replicated in practice, and reduce
research waste.
The aim of this review was to assess the reporting standards in RCTs of
AVB according to CONSORT-NPT guidance, specifically focusing on
intervention description, standardisation, adherence and clinician
expertise.