Editing Offender Assessment System (section)


{{About|the Offender Assessment System||OASYS (disambiguation)}}
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OASys is the abbreviated term for the '''Offender Assessment System''', used in England and Wales by [[His Majesty's Prison Service]] and the [[National Probation Service]] to measure the risks and needs of criminal offenders under their supervision. Initially developed in 2001, it was built upon the existing ‘What Works’ evidence base.<ref>{{Cite web |title=Assessment |url=https://www.justiceinspectorates.gov.uk/hmiprobation/research/the-evidence-base-probation/supervision-of-service-users/assessment/ |access-date=2022-08-24 |website=www.justiceinspectorates.gov.uk}}</ref>

OASys is designed to enable a properly trained and qualified individual; often a Probation Officer, to:
* assess how likely an offender is to be re-convicted
* identify and classify offending-related needs, including basic personality characteristics and cognitive behavioural problems
* assess risk of serious harm, risks to the individual and other risks
* assist with management of risk of harm
* links the assessment to the supervision or sentence plan
* indicate the need for further specialist assessments
* measure change during the period of supervision / sentence.

OASys comprises a series of [[computer]]-based forms on which clinical evaluations are made by staff of Offenders, and supervision and sentence plans for the forthcoming period of supervision are recorded on a periodic basis - typically every 16 weeks for [[community service|offenders in the community]], and less frequently for [[prison|imprisoned offenders]].

OASys supports the ''What Works?'' initiative of the Prison and Probation Services, by providing [[Performance metric|metric]]s by which the characteristics of offenders and their offences (inputs) can be analysed alongside information on interventions made (inputs) to the offender, and re-conviction data for offenders (outcomes), in order to enable refinement to be made to interventions (based on a consideration of the relation between inputs and outcomes)  as to improve outcomes - in other words, to decrease [[recidivism]] rates by ensuring that interventions are as appropriate and purposeful as possible.