MATERNAL AND EARLY CHILD HEALTH

Health Evidence Bulletins - Wales

Introduction

The original Protocols for Investment in Health Gain were written in the early 1990s to suggest areas where the introduction, or more widespread use, of certain practices could lead to worthwhile improvements in health for the people of Wales. The documents also highlighted current practices which were of questionable value. This revision has been prepared by reviewing the earlier Protocol for Investment in Health Gain: Maternal and Early Child Health(1) to provide some clear, updated statements with a precise indication of the strength of the evidence and its sources for each statement; and to introduce new statements covering subjects of important current interest.

The Maternal and Early Child Health Bulletin covers the health of the mother and her child from pre-conception through the perinatal period (up to one month of age). This is in contrast to the earlier Protocol which dealt with a small number of issues concerning the health of children up to the age of 5 years(2).

The statements represent a systematic summary of the evidence in this area found through a formal literature search across a wide range of sources(3). The evidence has been critically appraised using internationally accepted methods(4) compiled into this technical document under the direction of a public health physician, and reviewed by a multidiscipplinary team who are directly involved in patient care(5). In addition to this technical document, the information will be available electronically, via the NHS Cymruweb, and as succinct bulletins (Evidence Bulletins - Wales). Information on the methodology adopted (including a copy of the documentation), the formats in which the document is issued and details of other publications in the series, is available on request(6).

The convention used in this document to indicate the type of evidence is(7):

Top

‘Type I evidence’ - at least one good systematic review (including at least one randomised controlled trial).
‘Type II evidence’ - at least one good randomised controlled trial
‘Type III evidence’ - well designed interventional studies without randomisation
‘Type IV evidence’ - well designed observational studies
‘Type V evidence’ - expert opinion; influential reports and studies

 

Many health issues do not lend themselves to investigation by randomised controlled trial. By valuing evidence from these trials more highly than observational studies there is a danger that interventions with limited effectiveness might be judged to be more worthy than those based on observation. Similarly, those observational studies which clearly prove effectiveness (and make a randomised trial unethical) might be undervalued. Randomised controlled trials are a valuable form of evidence and, when available, they are included. If not, high quality evidence has been sought within the other categories. Information assigned as type V evidence includes very important reports or recommendations which should rightly be highly regarded.

Many health issues do not lend themselves to investigation be randomised controlled trial. By valuing evidence from these trials more highly than observational studies there is a danger that interventions with limited effectiveness might be judged to be more worthy than those based on observation. Similarly, these observational studies which clearly prove effectiveness (and make a randomised trail unethical) might be undervalued. Randomised controlled trials are a valuable form of evidence and, when available, they are included. If not, high quality evidence has been sought within the other categories. Information assigned as type V evidence includes very important reports or recommendations which should rightly be highly regarded.

The health gain notation (used to indicate the potential benefit to health) is(8):

‘beneficial’ - effectiveness clearly demonstrated (1)
‘likely to be beneficial’ - effectiveness not so firmly established (2)
‘trade-off between beneficial and adverse effects’ - effects weighed according to individual circumstances(3)
‘unknown’ - insufficient/inadequate for recommendation (4)
‘unlikely to be beneficial’ - ineffectiveness is not as clearly demonstrated as for 6 (5)
‘likely to be ineffective or harmful’ - ineffectiveness or harm clearly demonstrated (6)

Top

It should be stressed that these gradings, while aiming to be impartial, represent only the best advice of the professionals involved in preparing the Bulletin. Although the statements are deliberately brief, statistically significant quantitative information has been provided where possible. This is usually given as Number Needed to Treat (NNT), Odds Ratio (OR) or % change, in keeping with the original source of the information(9). Cost-benefit issues are not considered.

In keeping with the original Protocols, these revised documents are designed to assist Health Authorities in developing local strategies and in purchasing high quality health care. It is anticipated, however, that they will be of value to all health professionals in keeping abreast of the huge and increasing body of medical literature and can provide an agenda for future action in a wide variety of settings. It should be stressed that the publications will act as a supplement to, not a substitute for, clinical skills and experience. We anticipate that some of the conclusions reached will be controversial. Every effort has been made to include the best evidence within a subject area. Readers who are aware of any important studies that have been overlooked are encouraged to contact the project team(10).

The Maternal and Early Child Health Bulletin

This document has drawn extensively on the pioneering and comprehensive work of Chalmers, Enkin and Keirse in Effective Care in Pregnancy and Childbirth(11). References are given to this document and also to the associated handbook A Guide to Effective Care in Pregnancy and Childbirth(12) which, while lacking source references, is widely read and easily available. Where an updated review is available from the current edition of the Cochrane Library(13) this is referenced in preference to the original text

The statements within each subject area concentrate on specific interventions and the current state of knowledge. Expert recommendations for good practice which are common to all the subjects covered include:

Top

Support within the health service should be available to ensure that all pregnant women and their babies have access to appropriate standards of care; Intensive Care (for the mother); Special or Neonatal Intensive Care (for the baby) and transfer, when necessary, by paramedic equipped ambulance with appropriate professional help.

 

This initiative is funded by the Wales Office of Research and Development for Health and Social Care.

Internal Review Group, Maternal and Early Child Health Protocol January 1998


  1. Welsh Health Planning Forum. Cardiff: Welsh Office NHS Directorate, August 1991
  2. A document which discusses many of the health issues relating to the child from one month - 5 years of age has been recently published by the Welsh Office.  Health of Children in Wales.  Cardiff: Welsh Office, 1997
  3. Barker J, Weightman AL, and Lancaster J.   Project for the Enhancement of the Welsh Protocols for Investment in Health Gain: Project Methodology 2.  Cardiff: Duthie Library UWCM, 1997
  4. See 3
  5. See Contributors
  6. Contact: Protocol Enhancement Project Office, Duthie Library, UWCM, Heath Park, Cardiff CF4 4XN
  7. This table is adapted from the Bandolier system (derived from the work at the McMaster University, Canada) using the NHS Centre for Reviews and Dissemination criteria for a systematic review.  See ref.3 or http://www.jr2.ox.ac.uk/Bandolier/band6/b6-5.html and the Database of Abstracts of Reviews of Effectiveness (DARE) in the Cochrane library.
  8. This Notation is modified from the tables used in Enkin M, Keirse MJNC, Refnfrew m and Neilson J. A guide to effective care in pregnancy ad childbirth. 2nd ed. Oxford: Oxford University Press, 1995.
  9. Number Needed to Treat (NNT) = The number of patients to be treated to be sure of gaining one positive outcome; Odds Ratio (OR): If equal to 1, the effects of the treatment are no different to those of the control treatment. If the OR is greater (or less) than 1, then the effects of the treatment are more (or less) than those of the control treatment. Note that the effect being measured may be adverse or desirable.
  10. See 6
  11. Chalmers I, Enkin M, Keirse MJNC (eds.) Effective care in pregnancy and childbirth. Oxford, Oxford University Press, 1989
  12. Enkin m, Keirse MNJC, Renfrew M, Neilson J. A guide to effective care in pregnancy and childbirth. 2nd ed. Oxford: Oxford University Press, 1995
  13. Available at most health libraries on CD-ROM from Update Software, PO Box 696, Oxford OX2 7YX. Abstracts of the Cochrane Database of Systematic Reviews are now available on http://www.hcn.net.au/
Top

Contents Home

Health Evidence Bulletins: Wales, Duthie Library, UWCM, Cardiff CF14 4XN. e-mail: weightmanal@cardiff.ac.uk