Selecting a mental health needs assessment scale: guidance on the critical appraisal of standardized measures.

The assessment of need has become a central element of the NHS policy on mental health care. Despite the importance placed on a needs-led mental health service, little guidance has been provided as to the most appropriate means of assessing need. The use of standardized instruments can facilitate a systematic approach to the needs assessment process. However, available mental health needs assessment scales (MHNAS) vary considerably. Care is required to ensure that the scale selected is appropriate to the proposed purpose. This paper presents practical guidance on instrument selection for potential users of MHNAS including: (1) a review of the key issues to be considered when selecting an assessment scale, (2) a critical appraisal checklist for use in the review of needs assessment scales, and (3) a comparative analysis of three of the most commonly cited needs assessment scales. In addition, recommendations are made of ways to improve both the accessibility of MNHAS and to facilitate their appraisal prior to application in a clinical or research setting.