Introduction

Top Abstract Introduction Subjects and methods Results Discussion References

Although local circumstances must always be taken into account, it is acknowledged that as far as possible clinical practice should be guided by rigorous evidence from large trials or systematic reviews. ^{1 2} This is because traditional review articles or textbooks often contain recommendations based on clinical impression or evidence outdated years ago.³ Much time and effort are being invested in writing systematic reviews, but it is unclear whether reviews can be used directly by those in charge of clinical units to inform and improve local practice and patient outcome.

Like other clinical specialists, ^{4 5} obstetricians ^{6 7} have found it difficult to change their practice in line with mounting evidencefor example, giving corticosteroids to fewer than 20% of women in preterm labour.⁸ However, in the United Kingdom, 83% of consultant obstetricians stated that they would be willing to change their practice if provided with conclusive evidence from randomised trials.⁹ The Cochrane Collaboration published a comprehensive database of over 600 systematic reviews on pregnancy and childbirth, the Cochrane module on pregnancy and childbirth,¹⁰ so we sought a method to help obstetric units use the evidence contained in the reviews to inform their clinical practice.

To identify existing information sources for obstetricians¹¹ and potential local obstacles to change ^{12 13} in English obstetric units, we surveyed all UK teaching hospitals and a random sample of obstetric units in district general hospitals. ^{14 15} As well as identifying potential barriers to evidence based obstetrics, our survey showed that only 1 in 6 district general units had access to the Cochrane review database. After publication of our survey, several NHS regions distributed copies of the database to district general hospitals, and some organised formal didactic conferences to introduce the Cochrane module on pregnancy and childbirth to clinicians. However, even posting attractively presented information to healthcare professionals can fail to change their practice ^{16 17} ; posting a database containing systematic reviews seemed even less likely to succeed. Similarly, large scale, formal continuing educational activities usually fail to change clinical practice, whereas small scale educational sessions in which the participants decide the agenda are more effective. ^{17 18}

To ensure that evidence from systematic reviews informs clinical practice in district general hospitals, we believe that those professionals who lead clinical departments should appreciate evidence based medicine and how to incorporate review evidence into effective implementation methods to influence their staff, such as wall posters or practice guidelines. ^{12 17-19} Junior staff alone are unlikely to bring about significant innovation, especially if it requires new equipment or supplies, without the support of senior staff to mandate and fund such changes. In addition, senior clinical staff share some characteristics with the locally nominated opinion leaders whom Lomas and colleagues showed can be a powerful force in changing clinical practice.²⁰ Finally, targeting two or three senior staff rather than all unit clinicians costs less NHS time, makes it easier to arrange meetings without disrupting clinical activity, and leaves senior staff free to reflect on the evidence, local barriers, constraints, and needs before they select targets and implementation methods sensitive to local circumstances. Thus, for example, if heads of units identify low rates of prophylactic antibiotic use in caesarean section as a priority, they may want to approach anaesthetists rather than their own junior staff if this seems the most appropriate implementation route.

To help senior unit staff to appreciate evidence based medicine and how to incorporate review evidence into effective implementation methods, we decided to use educational visits. Educational outreach or academic detailing visits are effective at changing specific clinical practices²¹ and are extensively used by the pharmaceutical industry to manipulate physicians' prescribing for commercial reasons. In educational outreach a knowledgeable person visits each target clinician to explore a problem and possible local solutions, discuss their concerns, and provide attractive documents summarising key facts.²² However, the time and travel required can be costly¹⁷ and there are reports of outreach failing, ^{23 24} perhaps because of failure to identify local barriers to change. In Canada, outreach visits to opinion leaders in midwifery failed to change unit midwifery practice, probably because obstetricians were not targeted at the same time.²⁴

Educational visits have not been evaluated for their potential to bring about a general change in emphasis, such as a greater appreciation of evidence based medicine. Current evidence suggests that combining two or more implementation strategies, such as educational visits, to those individuals who are best placed to determine local barriers to change and adjust unit policy, is most likely to be effective. ^{12 17-19} Our aim was to test if this strategy was an effective, economical method to enhance the uptake of evidence from Cochrane reviews in district general obstetric units as a pilot for other Cochrane specialty databases.

	Subjects and methods

Top Abstract Introduction Subjects and methods Results Discussion References

We conducted a randomised controlled trial to test the hypothesis that a single educational visit to the lead obstetrician and midwife in district general obstetric units, outlining the principles of evidence based medicine and ways they might apply evidence from Cochrane pregnancy and childbirth reviews in their unit, would enhance application of this evidence after 9 months, measured by changes in four marker clinical practices.

Intervention
We targeted our educational visits to the lead obstetrician and midwife on the labour ward, whom we equated with Lomas and colleagues' opinion leaders²⁰ because they had usually been nominated to hold these positions by peers as being the most involved in labour ward management, policy making, and training. We deliberately limited the intervention to a single informal 1.5-3 hour visit by RJ (a nationally respected obstetrician and author of several Cochrane pregnancy and childbirth reviews) and a research midwife, as there is good evidence that a single educational visit can be effective.²¹ Also, if the intervention proved cost effective it could be used nationally.

View larger version (13K): [in this window] [in a new window]   Fig 1.   Anticipated role of educational visits in enhancing uptake of evidence in obstetric practice

Trial design
Our intention was to enhance the application of evidence by the whole labour ward team so, to minimise contamination, the unit of randomisation and analysis was the obstetric unit. Each obstetric unit was given an identifier then stratified according to NHS region, annual delivery rate, possession of the Cochrane module on pregnancy and childbirth at baseline, and distance from the nearest teaching hospital. Annual delivery rate, possession of the Cochrane module, and distance from the nearest teaching hospital were taken as surrogates for exposure to evidence based medicine. Obstetric units were allocated to intervention or control group by the toss of a coin (fig 2). To eliminate bias during data collection at follow up by a second research midwife, and to allow blinded assessment of guideline quality, the allocation was concealed from everyone except JCW, DGA, RJ, and the first research midwife. As only 25 obstetric units were available for randomisation, and accurate baseline figures for the rates and variability of the four marker clinical practices were not available, sample size calculation was not carried out, but confidence intervals are given for the results.

View larger version (12K): [in this window] [in a new window]   Fig 2.    Trial design

Participants
We included all consultant led district general obstetric units with more than 1500 deliveries per annum in two former NHS regions (North East and South West Thames). We excluded one smaller unit (1200 deliveries per annum) and three university teaching units because we suspected that the professional roles and relationships in these differed from the large district general units, which form 90% of UK units. Our sample included 25 district units in the two regions and formed 15% of all English obstetric units. The consultant obstetrician designated as head of labour ward, and the labour ward midwifery manager, participated in the educational visits.

Measures
One research midwife collected the baseline data in 1994 in all 25 obstetric units, and another collected the follow up data 9 months later. The research midwives were blind to which were intervention units. At each unit the research midwife conducted chart audits and obtained copies of labour ward guidelines. Data collection was preceded by a letter from the regional health authority informing staff, and by telephone calls to arrange an appointment. To reduce Hawthorne effects, data from patients discharged less than 1 month before either data collection exercise were excluded, and staff were not informed about data collection at follow up until 2 weeks beforehand. Researchers reassured staff that no data would be attributable to individual staff members or obstetric units.

Data analysis
Because we randomised obstetric units, to avoid the "unit of analysis" error we analysed the rates of marker clinical practices by obstetric unit.²⁸ No unit was excluded after randomisation, all intervention units participated in the visits, and data on clinical practices were available for all units, although smaller numbers of case notes were obtainable than planned for steroid usage.

Ethics
Approval for the trial was given by regional research and development and audit directors. Senior staff in all obstetric units gave permission for chart audits as part of an external audit project approved and funded by the regional health authority. Ethical advice indicated that, since we were only providing information to clinicians, there was no reason to seek patient consent.

	Results

Top Abstract Introduction Subjects and methods Results Discussion References

Characteristics and comparability of obstetric units
The mean annual delivery rate in the 25 obstetric units was 3200 births (1800-4500): 3330 in intervention units and 3050 in control units. However, despite randomisation there were baseline differences in two of the four clinical practices: use of ventouse was 36% (130/360) in intervention units and 55% (212/390) in control units, and use of polyglycolic acid sutures was 8% (30/347) in intervention units and 26% (89/354) in control units. There were no other baseline differences.

Actual clinical practices
The average rates for all 25 obstetric units at baseline were 18% (119/701) for use of polyglycolic acid sutures, 46% (342/750) for use of ventouse, 59% (412/707) for use of prophylactic antibiotics in caesarean section, and 72% (113/154) for use of steroids in preterm delivery (table). However, these mean figures hide wide baseline variations between individual units (fig 3).

View larger version (16K): [in this window] [in a new window]   Fig 3.    Rates of ventouse use at baseline and follow up for each obstetric unit. Units above diagonal increased ventouse usage during trial

Availability of the Cochrane module on pregnancy and childbirth, and guideline quality
At baseline, the Cochrane module on pregnancy and childbirth was available in six of 13 (46%) control units and six of 12 (50%) intervention units. At follow up the module was available in 10 (77%) control units; we had donated a copy to all intervention units.

Costs
The fixed cost of preparing the video was £5000, and the variable costs per visit for travel (£25), hotel accommodation (£60), staff time (£330), and sundries totalled £445. Thus, the mean cost per visit was £860 (at 1995 prices).

	Discussion

Top Abstract Introduction Subjects and methods Results Discussion References

Our data show encouraging trends in the number of obstetric units practising according to the evidence contained in the Cochrane module on pregnancy and childbirth. During the study period ventouse usage increased significantly more in intervention units than in control units, but there was no difference in the use of steroids for preterm delivery in either control units or intervention units. Increases in use of polyglycolic acid sutures and use of antibiotics in caesarean section over the study period were similar in control units and intervention units, with no difference attributable to the visit. Educational visits were associated with a significantly higher uptake of Cochrane review evidence relevant to only one of the four clinical practices studied.

Taking a conservative view, the educational visit led to only a modest difference between control units and intervention units in the extent to which clinical practice was based on evidence, and no change in the extent to which practice guidelines were based on evidence. This is similar to the results of a more intensive social marketing intervention to Canadian midwives by Hodnett and colleagues, though these investigators attributed their failure to excluding obstetricians.²⁴

Internal and external validity
Our study was a rigorous randomised trial of educational visits as a method for helping obstetricians and midwives identify and implement evidence from the Cochrane module on pregnancy and childbirth in their units. We recruited, randomised, and followed up 25 of the 26 district general obstetric units in two former NHS regions. Four representative, common clinical practices linked closely to patient outcomes were assessed. The assessor was blind to unit allocation. A Hawthorne effect is unlikely as clinical practice data were obtained from notes of patients who gave birth at least 1 month before data collection, and we informed obstetric units that we were conducting a regionally coordinated audit only a fortnight beforehand. While we did not directly measure patient outcomes, we chose our four marker practices because they have been shown in systematic reviews to improve major outcomes, so were valid surrogates. ^{10 29}

Study limitations
There are several possible explanations for our failure to show much effect of the educational visits. It is possible that longer or repeated visits might work better, but these would be harder to deploy on a national scale. Single visits have worked well in the past for influencing individual clinical practices, and usually do so quite rapidly.²¹ Contamination between intervention units and control units is unlikely as randomisation was by hospital, rather than by patient or professional. We did not ask obstetric unit staff to nominate colleagues most influential to their education, as has been done in other studies,²⁰ but instead targeted the obstetrician most involved with the labour ward, and the midwifery manager. These individuals may not be as academically influential as university based opinion leaders,²⁰ but they are constantly on hand, and they are in a stronger position to identify and remove barriers to evidence based practice in their own unit than outsiders.

Study implications
Important lessons from our study for others conducting such implementation research are firstly, that it is hard to improve on baseline rates for clinical practices of 60% or 80%. By analogy with clinical practice, where specific treatment is given only to diseased patients, our support should be focused where it is most needed. Secondly, the heterogeneity of clinical practice (rates for all practices varied between units from 0 to 100%) or the passive diffusion of innovation in control units during the study period must not be underestimated. Finally, data we shall report elsewhere show very large mismatches between the policies claimed by unit staff, their written guidelines, and actual clinical practice, emphasising the need to measure actual clinical practice and not rely on clinicians' statements or written guidelines.³³