• Using the CAPP

Using the CAPP

Operationalising the Conceptual Model

Having developed the conceptual model the next step was to develop methods for collecting information that would allow us to operationalise the model. We have prepared a series of procedures; these include a detailed manual, a semi-structured interview, an interview rating sheet, a symptom rating sheet, a staff rating scale, and a glossary of definitions. These are being, or have been, translated into a number of languages. We will provide brief descriptions of these instruments and describe their purposes.


The manual not only describes the conceptual basis of the model but also provides detailed instructions on how to carry out a CAPP assessment. Instructions are provided about how to establish time-lines for the period under consideration and how to use ‘life-event’ methods to increase the reliability of recall of key events or incidents. The key information sources required are described, the rules for dealing with conflicting information are established and the criteria for defining symptom severity are specified.

Institutional Rating Scale (CAPP-IRS)

The current version of the CAPP – the CAPP-IRS – is for use in secure institutional settings. The procedures for this assessment include a detailed semi-structured interview, structured in terms of life themes rather than a symptom-by-symptom approach. It starts with consideration of current psychological wellbeing, going on to consider current goals and plans, day-to-day activities, relationships with others. We developed questions to target specific symptoms; these are colour coded within the interview protocol with subsidiary symptoms that might be informed by the question being noted in parenthesis. A list of illustrative indicators is provided to support the rater in their judgements. Adjectival descriptive ratings in which the rater determines the extent to which specific trait descriptive adjectives apply are also provided.

Scoring of the CAPP-IRS interview is supported by two rating sheets - the Interview rating sheet and the Symptom rating sheet. These provide raters with a procedure for recording their ratings. The Interviewer Rating Sheet is the means by which interview information is recorded and noted. The Symptom Rating Sheet is completed subsequently and it is designed to allow the interviewer to make his or her own final judgements about the symptoms of psychopathy.

CAPP-IRS: Staff Rating Scale

Within institutional settings staff have a central role in providing relevant information about patient or prisoner behaviour. In order to tap into this knowledge we developed the CAPP-IRS Staff rating scale. Staff rate the presence of symptoms in terms of severity, the applicability of trait descriptive adjectives, the presence of absence of illustrative indicators, and finally, they provide information about the presence of any idiosyncratic indicators. These idiosyncratic indicators can be used for research purposes to increase the bank of indicators that can be used, they can be used clinically when risk management plans are being developed.


The Glossary contains dictionary definitions of each of the trait descriptive adjectives used in the CAPP. The Glossary provides essential support to the assessment process by helping assessors be clear about the differences among the traits on which they are rating their clients. The Glossary is therefore a contribution towards ensuring the consistency with which the CAPP is applied in institutional settings, which will be evident in measurements of the reliability of the instrument.