The SIPP Project
Validity studies of the Severity Indices of Personality Problems (SIPP)
The Severity Indices of Personality Problems (SIPP) questionnaire is a relatively new instrument, developed to measure individual differences in what are considered “core components” of personality disorders (Andrea et al., 2007; Verheul et al., 2008). This represents a significant supplement to the current categorical classifications of this type of disorder. The questionnaire has been used in a number of clinical contexts, and has proven to be a promising and useful instrument. Interpretations of scores from the instrument, however, depend on what is the "normal" variation in the population the instrument is used, and what counts as high or low scores.
In order to draw conclusions from scores on SIPP, one depends on estimates for variation and average scores from a non-clinical sample with which it is reasonable to compare. Previously, such estimates were only available from the Netherlands, and it was uncertain to what extent these could be generalized to Norwegian conditions. There was therefore a need for a survey from a randomly selected Norwegian normal sample. This study has now been completed.
Norwegian norms will serve as a better reference for assessments of what is considered high or low scores on the instrument. This will represent an enhanced quality when clinicians are to draw conclusions from SIPP scores. The validity of the instrument must nevertheless be examined in several contexts. One must see if it is sensitive to change, as well as sensitive to the severity of mental disorders. One must also identify whether the instrument is sensitive to group differences, for example whether it is able to detect differences between borderline and avoidant personality disorder, or personality disorder and substance abuse disorders.
In a planned collection of publications, these questions will be answered, which will form the basis for a good validation of the instrument. To date, the following studies have been published:
- Pedersen G, Arnevik E, Walderhaug E, Hummelen B & Wilberg T (2017). Psychometric Properties of the Severity Indices of Personality Problems (SIPP) in Two Samples: A Norwegian Community Sample and Clinical Samples of Patients With and Without Personality Disorders. European Journal of Psychological Assessment. DOI: 10.1027/1015-5759/a000436
- Arnevik EA, Pedersen G, Walderhaug E, Lien I, Wilberg T & Hummelen B (2019). Measuring personality problems in patients with substance use disorders: a cross-sample validation. Journal of Dual Diagnosis, 15, 324-332. doi: 10.1080/15504263.2019.1668583
- Paap M.C.S., Hummelen B, Arnevik E.A, Walderhaug E, Wilberg T, Berghuis H, Hutsebaut J & Pedersen G (2020). A multi-center psychometric evaluation of The Severity Indices of Personality Problems 118 (SIPP-118): Do we really need all those facets? Quality of Life Research, https://link.springer.com/article/10.1007/s11136-020-02654-8
- Espen Ajo Arnevik (project leader) - Department for Research and Innovation, Division of Mental Health and Addiction, Section for Clinical Addiction Research, Oslo University Hospital, Oslo, Norway.
- Geir Pedersen - Department for National and Regional Functions, Division of Mental Health and Addiction, Network for Personality Disorders, Section for Personality Psychiatry and Specialized Treatments, Oslo University Hospital, Oslo, Norway. Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
- Theresa Wilberg - Department for Research and Innovation, Clinic for Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
- Espen Walderhaug - Department of Addiction Treatment, Oslo University Hospital, Oslo, Norway.
- Benjamin Hummelen - Department for Research and Innovation, Division of Mental Health and Addiction, Section for Treatment Research, Oslo University
- Hospital, Oslo, Norway.
Andrea, H., Verheul, R., Berghout, C., Dolan, C., Vanderkroft, P., Busschbach, J., Bateman, A., & Fonagy, P. (2007). Measuring the Core Components of Maladaptive Personality: Severity Indices of Personality Problems (SIPP-118) - The first technical report. Viersprong Institute for Studies on Personality Disorders (VISPD) Medical Psychology and Psychotherapy, Netherlands.
Verheul, R., Andrea, H., Berghout, C. C., Dolan, C., Busschbach, J. J., van der Kroft, P. J., Bateman, A. W., & Fonagy, P. (2008). Severity Indices of Personality Problems (SIPP-118): development, factor structure, reliability, and validity. Psychological Assessment, 20, 23–34.
Arnevik E, Wilberg T, Andrea H, Monsen JT & Karterud S (2009). A cross-national validity study of the Severity Indices of personality problems (SIPP-118). Personality and Mental Health. Personality and Mental Health, 3, 41–55.