Health Evidence Bulletins - Wales

Mental Health Bulletin


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: Mental Health to provide some clear, updated statements with a precise indication of the sources for each statement; and to introduce new statements arising from the literature since the original Protocol was produced.

In keeping with the original Protocols, it should be stressed that these revised documents are designed to assist health authorities in developing local strategies and in commissioning 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 may inform the research and development programme.

The statements represent a methodical summary of the evidence in this area found through a formal literature search across a wide range of sources. The evidence has been critically appraised using internationally accepted methods2 compiled into this document under the direction of a public health physician, and reviewed by a multidisciplinary team who are directly involved in patient care. 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.

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

‘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

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.


The Mental Health Bulletin

The original Mental Health Protocol covered mental health issues by disease categories and patient groups. In this bulletin most of this work has been reviewed. The decision was made however to exclude child and adolescent mental health as to include it would have made the task too large given the resources available to the review group. This does not however mean that child and adolescent mental health is considered to be of lesser importance. From everyone’s point of view this is very clearly not the case and it is hoped that this area will also be reviewed soon. For the same reason the review has been limited largely to consideration of Type I and Type II evidence.

Within the field of mental health there are contributions from many other professionals, agencies, the voluntary sector and the community itself. The health service and diagnosis-based orientation of this bulletin is not intended to suggest that good mental health is solely the preserve of the health service, or that good research does not exist for other approaches. Rather, this bulletin makes a start in developing a whole system approach by bringing together evidence for the effectiveness of largely medical and health service interventions. It is important that these deficiencies are recognised and rectified in any further extension to the work.

Most of this review was undertaken using an earlier methodology and before the decision to include measures of benefit. A conscious decision has therefore been made not to include this categorisation. To do so would involve very much more discussion with the professionals on the internal review group than was possible within the project . Not to have the debate could lead to a misleading impression of certainty of benefit in some cases. This bulletin is therefore a useful update on the original but is not a comprehensive and final document. Indeed reference is made in the document to work which we know to be in progress, for example from the Cochrane Collaboration. This document should be a useful contribution to the current review of health strategies and both published and electronic versions of the bulletin will be regularly updated to reference the latest evidence.


The work on depression and psychotherapy draws extensively on the systematic reviews undertaken by the American Psychiatric Association (APA) and Roth and Fonagy on behalf the Department of Health. These reviews each cover a large body of literature which has been critically appraised by experts and, in the case of APA work, the conclusions are expressed as guidelines and protocols. They are the best reviews available but care does need to be exercised in translating their guidelines into practice in Wales, given the differences between populations and professional practices between countries. The statements here are therefore broad and should be useful to Health Authorities in commissioning services. Clinicians wishing to use this evidence to alter their clinical practice are however strongly recommended to read the source documents themselves and assess how the literature relates to their particular clinical situation.

The issues surrounding the generalisability of the findings of research conducted in ideal, controlled circumstances on large populations, to individuals in normal clinical practice, are the same in the mental health field as in other areas of medical research. Chapter two of Roth and Fonagy’s book explores the difficulties of conducting and interpreting research and, whilst it is written in the context of psychotherapeutic research, the principles apply equally to other types of intervention and should be considered as essential reading for anyone wishing to understand, interpret or undertake research.

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:


Project Team and Internal Review Group, June 1998

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

  1. Welsh Health Planning Forum. Cardiff: Welsh Office NHS Directorate, April 1993
  2. Barker J, Weightman AL, Lancaster J. Project for the Enhancement of the Welsh Protocols for Investment in Health Gain: Project Methodology 2. Cardiff: Duthie Library, 1997
  3. See contributors
  4. Contact: Protocol Enhancement Project Office, Duthie Library, UWCM, Heath Park, Cardiff CF4 4XN
  5. This table is adapted from the Bandoliet system (derived from the work at McMaster University, Canada) using the NHS Centre for Reviews and Dissemination criteria for a systematic review. See ref.2 or and the Database of Abstracts of Reviews of Effectiveness (DARE) in the Cochrane Library
  6. 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 from those of the control treatment. Of 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.
  7. Health gain notation. See ref. 2 for details
  8. American Psychiatric Association Practice Guidelines. Washington DC: APA, 1996;
  9. Roth A, Fonagy P.What Works for Whom? A Critical Review of Psychotherapy Research New York: The Guildford Press, 1996


Contents Home

Health Evidence Bulletins: Wales, Duthie Library, UWCM, Cardiff CF14 4XN. e-mail: