Do Cochrane summaries help student midwives understand the findings of Cochrane reviews: the BRIEF randomised trial

Article type
Authors
Alderdice F1, Lasserson T2, McNeill J1, Beller E3, Carroll M4, Hundley V5, Sunderland J6, Devane D7, Noyes J8, Keyes S9, Norris S10, Wyn-Davies J11, Clarke M1
1Queens University Belfast, United Kingdom
2Cochrane Editorial Unit, United Kingdom
3Bond University Queensland, Australia
4Trinity College Dublin, Ireland
5Bournemouth University, United Kingdom
6City University London, United Kingdom
7National University of Ireland, Galway, Ireland
8Bangor University, United Kingdom
9Edinburgh Napier, United Kingdom
10Swansea University, United Kingdom
11University of South Wales, United Kingdom
Abstract
Background:
Abstracts and plain language summaries (PLS) are often the first, and sometimes the only, point of contact for systematic reviews. It is important to identify how they are used and to know the impact of different elements, including the authors’ conclusions.

Objectives:
To assess whether (1) the abstract or the PLS of a Cochrane Review is a better aid for midwifery students in assessing the evidence; (2) inclusion of authors’ conclusions helps them; (3) there is an interaction between the type of summary and the presence or absence of the conclusions.

Methods:
813 midwifery students from 9 universities in the UK and Ireland were recruited to this 2 x 2 factorial trial (abstract v PLS, conclusions v no conclusions). They were randomly allocated to one of the four groups and asked to recall knowledge after reading one of four types of summaries of two Cochrane Reviews, one with clear findings and one with ambiguous findings (as assessed by an expert panel). The primary outcome was the proportion who gave the response the panel judged to be correct.

Results:
There was no statistically significant difference in correct response between Abstract and PLS groups in the clear findings example (Abstract: 59.6%; PLS: 64.2%; Risk difference 4.6%; CI -0.2 to 11.3) or the ambiguous findings example (42.7%; 39.3%; -3.4%; -10.1 to 3.4). There was no significant difference between conclusions and no conclusions groups in the example with clear findings (conclusions: 63.3%; no conclusions: 60.5%; 2.8%; -3.9 to 9.5) but there was a significant difference in the example with ambiguous findings (44.7%; 37.3%; 7.3%; 0.6 to 14.1 p=0.03). PLS without conclusions in the ambiguous findings example had the lowest proportion of correct responses (32.5%). Students given a PLS were more likely to report wanting to read the full review than those given the abstract.

Conclusions:
Abstracts with and without conclusions generated similar student responses. PLS with conclusions gave similar results to abstracts with and without conclusions but removing the conclusion from a PLS with ambiguous findings led to more problems with interpretation.