Related Experiment Video
Updated: Oct 15, 2025
07:36
An Experimental Analysis of Children's Ability to Provide a False Report about a Crime
Published on: May 3, 2016
8.7K
An Inventory of Problems-29 (IOP-29) study investigating feigned schizophrenia and random responding in a British
Christina L Winters1, Luciano Giromini2, Trevor J Crawford1
1Department of Psychology, Lancaster University, Lancaster, UK.
Summary
The Inventory of Problems-29 (IOP-29) effectively identifies feigned schizophrenia in UK adults. Its feigning scale (FDS) shows high accuracy, even with schizotypal traits, and a new scale shows promise for detecting random responding.
Area of Science:
- Psychological assessment
- Clinical psychology
- Forensic psychology
Background:
- Malingering research is limited in the UK due to a lack of validated symptom validity tests (SVTs).
- The Inventory of Problems-29 (IOP-29) is a potential tool for assessing response validity.
Purpose of the Study:
- To evaluate the validity of the IOP-29 in detecting feigned schizophrenia and random responding in a UK volunteer sample.
- To assess the impact of schizotypal traits on the IOP-29's detection accuracy.
Main Methods:
- An online study involving 151 British volunteers completing the IOP-29 under three conditions: honest responding, feigning schizophrenia, and random responding.
- Participants also completed the O-LIFE schizotypy measure.
Main Results:
- The IOP-29's feigning scale (FDS) demonstrated excellent validity in distinguishing honest from feigned schizophrenia (AUC = .99).
- Classification accuracy was not significantly influenced by the presence of schizotypal traits.
- A new IOP-29 scale for detecting random responding (RRS) showed promising results.
Conclusions:
- The IOP-29 is a valid instrument for detecting feigned schizophrenia in the UK.
- The IOP-29's feigning scale is robust against the influence of schizotypal traits.
- The IOP-29 shows potential for identifying random responding in psychological assessments.
Related Concept Videos
01:22Self-Report Tests of Personality
501
Self-report inventories are objective personality assessments that use multiple-choice items or numbered scales, typically ranging from 1 (strongly disagree) to 5 (strongly agree). They are often called Likert scales after Rensis Likert. These inventories are widely used due to their ease of administration and cost-effectiveness. One of the most prominent examples is the Minnesota Multiphasic Personality Inventory (MMPI), initially developed in the 1940s to assess abnormal personality traits.
501
03:20The Stanford Prison Experiment
23.9K
The famous and controversial Stanford Prison Experiment, conducted by social psychologist Philip Zimbardo and his colleagues at Stanford University, demonstrated the power of social roles, social norms, and scripts.
23.9K
00:57Deindividuation
28.1K
Deindividuation is a form of social influence on an individual’s behavior such that the individual engages in unusual or non-normal behavior while in a group setting. Why? Because in these group settings, the individual no longer sees themselves as an individual anymore, disinhibiting their behavior and personal restraint.
28.1K
01:22Personality Disorders: Paranoid and Schizoid
213
Personality disorders represent enduring cognition, affect, and behavior patterns that significantly deviate from societal norms. These maladaptive traits often lead to difficulties in various domains, including interpersonal relationships, occupational settings, and overall psychological well-being. Paranoid personality disorder and schizoid personality disorder are two distinct conditions marked by odd or eccentric behavior.
Paranoid Personality Disorder
Paranoid personality disorder is...
Paranoid Personality Disorder
Paranoid personality disorder is...
213