Utility of Collateral Informants to
Inform Treatment for Gambling
Disorder
Megan M. Petra, MSW
Renee M. Cunningham-Williams, PhD
Gambling Disorder (GD)
• DSM 5 now classifies Gambling Disorder (GD)
as an addictive disorder
• GD occurs in ~1-2% of the population, 1-3
• But is 6.5 times more likely in those with
substance use disorders
• Thus, clinicians are likely to have patients/
clients with GD
Screening, Diagnosis, & Treatment
• Accurate information on GD is critical 4
• But no biological “gold standard” test to verify
clients’ self-reports of gambling
• Collateral informants (CIs) may be able to
assist clinicians by providing information
Collateral Informants (CIs)
• Collateral informants are family or friends of
the client, who can report on their gambling
behavior
• If CIs’ information is accurate (concordant),
clinicians can use them to verify client selfreports
• This information will inform diagnostic and
treatment decisions
Research Objective
• Investigate concordance between gambler selfreports & CI reports
• Determine if concordance is:
– Associated with gambler-CI relationship
– Influenced by gamblers’ comorbid substance use
disorders (SUDs) or psychiatric disorders
Methods
• Community-recruited adults (N=128) who had
gambled at least five times in their lives
nominated CIs
• Gamblers & CIs interviewed separately via
phone
• Psychometric study of a computerized
diagnostic interview (C-Gam © 5)
Methods: Measures
• Gambler Measures
– DSM Gambling Disorder criteria (C-Gam © 5)
– DSM Substance Use Disorder criteria
(GAM-DA © 5)
– DSM Depression criteria (CES-D 6)
– DSM Personality disorder criteria (SCID-II 7)
• CI Measures
– DSM Gambling Disorder criteria for the gambler’s
behavior (GAM-CI © 5)
Methods: Concordance
• Cohen’s kappa (κ) & Interclass Correlation
Coefficient (ICC)
• Κ & ICC interpretation8:
–
–
–
–
–
Fair (0-.2)
Poor (.2-.4)
Moderate (.4-.6)
Substantial (.6-.8)
Almost perfect (.8-1.0)
• Comparisons made via Fisher’s Z
transformation
Results: Participant Demographics
• Gambler sex: 46% male, 54% female
• Gambler race: 76% Caucasian, 19% AfricanAmerican, 6% Other
• Gambler-CI relationship: 49% family member,
51% friend
Results: Overall Concordance
Concordance and
Gambler-CI Relationship
Concordance and Gambler
Personality Disorder
Concordance and
Gambler Depression
Concordance and Gambler
Substance Use Disorders
Implications
• Treatment providers can be confident in using
CIs to verify gambler self-reports
– Concordance is likely to be moderate – substantial
– Concordance is unaffected by gamblers’ comorbid
conditions
• Family members are better to use as CIs than
are friends
Conclusions
• CIs are a valuable source of information which
treatment providers can use to inform
diagnosis of Gambling Disorder, and treatment
decisions
References
1.
2.
3.
4.
5.
6.
7.
8.
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Acknowledgements
•
•
NIDA grants: T32DA07313 (Megan M. Petra,
Fellow; Renee M. Cunningham-Williams,
Director), K01DA00430 (RCW), R01
DA015032 (RCW)
Author contact: [email protected]