The expansion of IAPT services will aim to provide at least 1.5m adults with access to care each year by 2020/21. This means that IAPT services nationally will move from seeing around 15% of all people with anxiety and depression each year to 25%, and all areas will have more IAPT services. NHS Digital calculates the numerator for access rates – which is the number of referrals entering treatment in a given period – but the denominator (the prevalence of depression and anxiety in the England population) has been determined by NHS England. This is based on figures from the Adult Psychiatric Morbidity Survey, 2000.

Anxiety Disorder Specific Measure (ADSM)

Anxiety Disorder Specific Measures are questionnaires that are sensitive measures of the severity of anxiety disorders.

Assessment appointment

All IAPT appointments should be classified by their purpose. An assessment appointment is an attended appointment where the recorded appointment type is either ‘assessment’ or ‘assessment and treatment’.


Caseness is the term used to describe a referral that scores highly enough on measures of depression and anxiety to be classed as a clinical case. It is measured by using the scores that are collected at IAPT appointments; if a patient’s score is above the clinical / non-clinical cut off on either their anxiety score, their depression score, or both, then the referral is classed as a clinical case.

Completed course of treatment

See ‘Finished course of treatment’ below.

Entered treatment

To enter treatment, a referral must have a first treatment appointment recorded in the period. Some measures based on the first treatment appointment (for example, waiting times) look at a cohort of referrals that ended in the year, as this group represents referrals that have undergone the full IAPT pathway.

Finished course of treatment

A referral that has finished a course of treatment is one that has ended having had at least two attended treatment appointments during the referral. Follow-up appointments do not count; these should take place after the end of a course of treatment. All patients who have finished a course of treatment are eligible for assessment of outcome (recovery, reliable improvement, no reliable change, or reliable deterioration).


The Generalised Anxiety Disorder-7 questionnaire is IAPT’s default questionnaire for assessing the severity of anxiety. It was originally developed as a measure of Generalised Anxiety Disorder and can be used as an Anxiety Disorder Specific Measure (ADSM) for this clinical condition. However, it can also pick up changes in other anxiety disorders and is therefore used to measure change in anxiety where the relevant ADSM has not been given at least twice. The GAD7 should be recorded at every appointment.

Conversely, patients have shown no reliable change if they fail to show reliable change on both anxiety and depression measures, or if reliable improvement is shown on one whilst reliable deterioration is shown on the other.

National Institute for Health and Clinical Excellence (NICE)

NICE's role is to improve outcomes for people using the NHS and other public health and social care services. NICE approve and oversee therapy types used in the IAPT programme.

PHQ-9 questionnaire

The Public Health Questionnaire-9 is IAPT’s measure of the severity of depression and should be recorded at each appointment.

Problem descriptor

This describes the specific problem being assessed by the IAPT service for a given referral (for example, Obsessive Compulsive Disorder). The terminology was changed from ‘provisional diagnosis’ as it was felt that a formal diagnosis cannot always be made at initial contact with a patient, and that this sometimes only becomes apparent over the course of several appointments. For this reason, the problem descriptor can be updated in each submission. In the analysis of outcomes, the problem descriptor used is the last recorded one.

Recovery (moving to recovery)

Recovery is one of the key outcome measures in IAPT, and services are monitored in terms of the proportion of eligible patients who recover (known as the ‘recovery rate’ or ‘moved to recovery rate’).

To be eligible for the assessment of recovery, a patient must have completed a course of IAPT treatment (see definition ‘Finished course of treatment’) having started their course of treatment at ‘caseness’ (see definition ‘Caseness’). A patient has then moved to recovery if they are no longer at caseness at the end of their treatment.


To access IAPT services, an individual requires a referral. Referrals are often provided by General Practitioners (GPs), but there are many other sources of referral, including self-referral by the individual requiring the service. Once a referral has been received by a service provider, it should follow the recommended stepped care pathway.

One patient can only have one open referral at a given provider at any one time but could have multiple referrals across different providers or multiple referrals with the same provider across time. For this reason, a count of referrals is used, rather than a count of people, in IAPT publications.

There are three key stages for referrals in IAPT publications; referral received date, first treatment appointment date, and referral end date.

Reliable change (Reliable Improvement and Reliable Deterioration)

The severity of a patient’s condition in IAPT is assessed using tailored questionnaires (ADSM and PHQ-9 scores). All measures of symptoms are subject to error. Consequently, small changes in questionnaire scores may not indicate a real change in clinical state. A change of scores between the beginning and end of a course of treatment is considered a reliable change if it exceeds the measurement error of the questionnaire.