Rep36 Understanding Personality Disorder

3.1.3 Multiple sources of information and
dealing with conflict
Data obtained at interview should not necessarily
be taken at face value. The responses of clients
to interview questions may be limited by poor
insight into personality functioning and clients
in forensic settings may be additionally
hampered by a desire to mislead the interviewer
about the presence of characteristics perceived
to be negative (e.g. lack of empathy). Attempts
should be made to confirm or deny important
claims made by the client using clinical notes
compiled by others, criminal, educational and
employment records, and interviews with
relatives and friends. Where conflicts exist
between client and informant information, and
collateral information is thought to be credible,
this should alert the interviewer to the possibility
that the client is engaging in impression
management. New information should be sought
and careful consideration should be given to
sources that suggest greater difficulty or
pathology on the assumption that some people
may under-report or minimise pathological
symptomatology.
3.1.4 Comorbidity
Comorbidity refers to the co-occurrence of
different clinical or personality disorders.
Comorbidity may arise because disorders are
distinct and incidentally co-occurring.
Alternatively, co-occurrence may be an artefact
of, for example, shared or similar diagnostic
criteria, a common aetiology, sub-clinical versus
clinical representations of pathology (e.g.
schizotypal or paranoid personality disorder as
sub-clinical forms of psychotic disorder), or
vulnerability (e.g. the presence of avoidant
personality disorder creates a vulnerability to the
development of anxiety disorders). Comorbidity
research to date demonstrates the marked
tendency for Axis I and Axis II disorders to co-
occur. For example, research suggests that
between 66 per cent (Dahl, 1986) and 97 per
cent (Alnaes & Torgersen, 1988) of clients with
an Axis II disorder also have a diagnosable Axis I
disorder. Examined from the reverse perspective,
studies indicate that the number of clients with
Axis I disorders who also have an Axis II disorder
ranges from 13 per cent (Fabrega 
et al
., 1990) to
81 per cent (Alnaes & Torgersen, 1988). 
In general, the strongest relationships appear
to be between the substance use disorders and
the Cluster B personality disorders (the
relationship between antisocial personality
disorder and alcohol abuse and dependence is