Structured Anchored Clinical Judgements

Structured anchored clinical judgements (SACJs), also known as structured professional judgements (SPJs), were developed in an attempt to combine the expertise of clinical professionals with the numerical advantages of actuarial measures. There is some dispute as to how successful this has been.

The basic principle with these instruments is that they list a number of known risk factors (ideally, factors which have been demonstrated by research to be significant predictors). The assessor rates the offender on each of these factors. Normally, this is on a three-point scale, according to whether factor is thought to be absent, partially or possibly present, or fully present. Some instruments provide a score, and others expect the professionals to synthesise the information into an overall rating. Typically, this is a three level rating of either low, medium or high risk.

In some respects, these instruments are a useful aide-memoire to professionals, concentrating their attention on those factors which are known to be significant. However, there are a number of flaws in the rationale:
  1. Most SACJs were established in the 1990s before research actually identified what the risk factors were; many of the factors were a crystallisation of clinical practice (with all its flaws). However, once published, such instruments take on a life of their own - motivated by sales, not accuracy. For example, two of the 20 items in the SVR-20 assessment for sex offenders have been shown not to be predictive of reconviction.
  2. SACJs generally have a poor mathematical construction, so they use related items which in effect count the same characteristic twice (often personality disorder, which is only one risk factor, and not the most significant).
  3. Assessors are usually required to synthesise the result into an overall risk rating; there is no evidence that clinicians can do this, and studies of clinical methods give no grounds for optimism.
In addition to this, there are a number of practical problems with the SACJs:
  1. We often don’t have corroboration for the information we think we have (e.g., employment history, or evidence of early behaviour). This means we either have to omit the information, or take the offender's word for it.
  2. Most research on SACJs reduces the data to a numerical score, but most of the manuals advise against this; the result is that research only supports use of the instrument in an unauthorised way.
  3. Many assessments are carried out by trainee psychologists who lack the clinical experience necessary to rate the items; often, so do their supervisors. Many of them have not worked in other settings, and so have not had the experience of rating people's emotional states, insight, empathy, and a number of other factors which are typically used in these instruments.
  4. Offenders’ behaviour is probably influenced by the interviewer (e.g., appearing less empathic when the interviewer is part of the prison system). The nature of some SACJs, which require offenders to recall details of events and thought patterns many years previously, is such as to make some distortion almost inevitable.
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