What is the Threshold Assessment Grid (TAG)?
The TAG is a short, quickly completed assessment of the severity of an individual’s mental health problems. It was developed at King’s College London to help identify people who should be referred to community mental health services for adults and older people.
GPs or other health professionals can use the TAG to rate the severity of a individual’s difficulties by ticking boxes in seven domains.
The scores range from none (no problem in that particular domain) to either severe or very severe. In each domain, the person completing the assessment simply ticks the statement that best applies to the individual who is being assessed
The document you have downloaded has three pages. The first page is the TAG measure. The second page contains an evidence-based checklist that helps identify some of the important aspects to consider when rating each domain. The third page contains further guidance and more details on rating the TAG.
TAG is copyrighted so cannot be changed without permission. Free clinical, teaching and research use is permitted.
Who can use the TAG?
The TAG can be used by anyone who needs to decide whether the severity of a person’s mental health problems warrants contact with mental health services. A wide range of professionals have successfully completed the TAG, including GPs, psychiatrists, psychiatric nurses, care managers, liaison mental health team staff, health visitors, parole officers, physicians, psychologists, housing officers, alcohol workers and voluntary sector workers. Training is not required.
It takes less than five minutes to complete the assessment.
How is the TAG scored?
TAG is scored by summing the scores for each domain:
None = 0
Mild = 1
Moderate = 2
Severe = 3
Very severe = 4
Summing the seven domain scores in this way gives the total score, which ranges from 0 to a maximum 24 (4 Severe, 3 Very severe).
So, for an assessment comprising three None, two Mild and two Severe domains, the total score would be 8 (1+1+3+3).
Development of TAG
TAG was developed between 1996 and 1998 by Mike Slade and colleagues at the Institute of Psychiatry (now the Institute of Psychiatry, Psycholgy & Neuroscience), King’s College London.
The development process involved GPs, service users and carers, psychiatrists, psychologists, nurses, occupational therapists, care managers, housing workers and policy makers.
Representatives from each of these groups took part in a series of consensus workshops (n=57). This led to the development of a draft questionnaire, which was then refined and finalised using a Delphi Consultation (n=58).
The psychometric properties of the TAG were tested during 1999 and 2000, in a multi-site study involving 605 service users from 10 adult, elderly and day care mental health services throughout London.
The use of TAG to improve access from primary care to secondary mental health services was investigated in a multi-site cluster randomised controlled trial. The study took place in 73 GP practices (408,839 patients) in London and Manchester from 2002 until 2005.
Sensitivity and specificity analysis found that a TAG score of 5 or more is a defensible approach to identifying people with severe mental heath problems. This brief approach to screening is used as an inclusion criterion in many research studies.
You have permission to translate TAG if:
a) the following statement is made in English and your local language on your translation:
TAG was developed in English by Mike Slade and colleagues at King’s College London. Further information available from researchintorecovery.com/tag. This version was translated into <language> by <your name and contact details>
b) your translation is distributed free of charge by you to academic and clinical colleagues who request a copy, and no charge is made for its use for research, clinical or teaching purposes.
c) you send a copy to us (email: firstname.lastname@example.org) to include as a download in our below list of translations.
Translations must be comparable with the original English TAG. Minor modifications can be made to the wording for each item to maximize conceptual equivalence, but other elements (7 domains, rating scale etc) cannot be changed. We particularly encourage the development of high-quality translations, for example by following a formal methodology for translation, such as described here.
Download TAG Translations
The reference for the TAG is:
Slade M, Powell R, Rosen A, Strathdee G (2000) Threshold Assessment Grid (TAG): the development of a valid and brief scale to assess the severity of mental illness, Social Psychiatry and Psychiatric Epidemiology, 35, 78-85.
The psychometric properties of the TAG were evaluated:
Slade M, Cahill S, Kelsey W, Powell R, Strathdee G (2002) Threshold 2: The reliability, validity and sensitivity to change of the Threshold Assessment Grid (TAG), Acta Psychiatrica Scandinavica, 106, 453-460.
The feasibility of the TAG for routine use was evaluated:
Slade M, Cahill C, Kelsey W, Powell R, Strathdee G, Valiakalayil A (2001) Threshold 3: The feasibility of the Threshold Assessment Grid (TAG) for routine assessment of the severity of mental health problems, Social Psychiatry and Psychiatric Epidemiology, 36, 516-521.
The screening criterion of a TAG score of 5 or more was empirically established:
Slade M, Cahill S, Kelsey W, Leese M, Powell R, Strathdee G (2003) Threshold 4: an evaluation of the Threshold Assessment Grid as an aid to mental health referrals, Primary Care Mental Health, 1, 45-54.
The use of this screening criterion was then tested in a cluster RCT involving 73 GP practices:
Slade M, Gask L, Leese M, McCrone P, Montaňa C, Powell R, Stewart M, Chew-Graham C (2008) Failure to improve appropriateness of referrals to adult community mental health services – lessons from a multi-site cluster-randomised controlled trial, Family Practice, 25, 181-190.
A nested process evaluation explored the rhetoric and reality of the primary-secondary care interface:
Chew-Graham C, Slade M, Montaňa C, Stewart M, Gask L (2007) A qualitative study of referral to community mental health teams in the UK: exploring the rhetoric and the reality, BMC Health Services Research, 7, 117.
TAG was compared with other standardised measures, and shown to be useful as a measure of global severity:
Salvi G, Leese M, Slade M (2005) Routine use of mental health outcome assessments: choosing the measure, British Journal of Psychiatry, 186, 146-152.
TAG has been translated into a number of languages, and is now in use in international studies as a screening tool:
Puschner B, Becker T, Mayer B, Jordan H, Maj M, Fiorillo A, Égerházi A, Ivánka T, Munk-Jørgensen P, Krogsgaard Bording M, Rössler W, Kawohl W, Slade M, for the CEDAR study group (2016) Clinical decision making and outcome in the routine care of people with severe mental illness across Europe (CEDAR), Epidemiology and Psychiatric Sciences, 25, 69-79.