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Severity indices of personality problems–short form in old-age psychiatry

Van Reijswoud, Barbera E.; Debast, Inge; Videler, Arjan C.; Rossi, Gina; Lobbestael, Jill;Segal, Daniel L.; Van Alphen, Sebastiaan P. J.Published in:Journal of Personality Assessment

DOI:10.1080/00223891.2020.1743710

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Severity Indices of Personality Problems–ShortForm in Old-Age Psychiatry: Reliability and Validity

Barbera E. van Reijswoud, Inge Debast, Arjan C. Videler, Gina Rossi, JillLobbestael, Daniel L. Segal & Sebastiaan P. J. van Alphen

To cite this article: Barbera E. van Reijswoud, Inge Debast, Arjan C. Videler, Gina Rossi, JillLobbestael, Daniel L. Segal & Sebastiaan P. J. van Alphen (2020): Severity Indices of PersonalityProblems–Short Form in Old-Age Psychiatry: Reliability and Validity, Journal of PersonalityAssessment, DOI: 10.1080/00223891.2020.1743710

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Severity Indices of Personality Problems–Short Form in Old-Age Psychiatry:Reliability and Validity

Barbera E. van Reijswoud1, Inge Debast2, Arjan C. Videler3 , Gina Rossi2, Jill Lobbestael4, Daniel L. Segal5, andSebastiaan P. J. van Alphen2

1Mondriaan Institute for Mental Healthcare, Heerlen, Netherlands; 2Department of Clinical and Lifespan Psychology, Free University Brussels,Brussels, Belgium; 3Breburg Institute for Mental Health Care, Breda, The Netherlands; 4Department of Clinical Psychology Sciences,Maastricht University, Maastricht, The Netherlands; 5Department of Psychology, University of Colorado

ABSTRACTThe Severity Indices of Personality Problems (SIPP; Verheul et al., 2008) is a popular self-reportquestionnaire that measures severity of maladaptive personality functioning. Two studies demon-strated the utility of the short form (SIPP–SF) among older adults but validation in clinical settingsis lacking. Therefore, we examined the psychometric properties of the SIPP–SF in a large sampleof older adult Dutch outpatients (N¼ 124; age range ¼ 60–85 years, M¼ 69.8, SD¼ 5.3). TheSIPP–SF domains showed good to excellent internal reliability (Cronbach’s a ¼ .75–.91) and effect-ively discriminated between participants with and without a personality disorder, as assessed withthe Structured Clinical Interview for DSM–IV Axis II Personality Disorders (SCID–II). Convergent val-idity of the SIPP–SF was examined with instruments for measuring personality pathology amongolder adults (Informant Personality questionnaire [HAP]; Gerontological Personality Disorders Scale[GPS]). The GPS generally correlated with the SIPP–SF domains in expected directions, with smallto large effect sizes. For the HAP, only 1 scale correlated with all SIPP–SF domains. No associationswere found between the SIPP–SF and psychiatric symptomatology as measured by the BriefSymptom Inventory (BSI). The SIPP–SF appears to be a promising instrument for assessing mal-adaptive personality functioning among older adult outpatients.

ARTICLE HISTORYReceived 9 April 2019Accepted 15 February 2020

The assessment of personality disorders (PDs) in later life,age 65 years and older, is known to be particularly problem-atic because many of the diagnostic criteria for PDs in theDiagnostic and Statistical Manual of Mental Disorders (5thed. [DSM–5]; American Psychiatric Association, 2013) arenot adequately attuned to older adults and the unique lifecontext of old age (e.g., Rossi et al., 2014; Segal et al., 2006).As a result, almost a third of the PD symptoms defined inDSM–5 are expressed differently in later life (Balsis et al.,2007). This problem negatively affects the reliability, validity,and utility of the PD construct in older adults, and fre-quently leads to misdiagnosing PDs in later life (Debastet al., 2017).

The prevalence of PDs among older adults in the generalpopulation is estimated around 8% (Schuster et al., 2013).Among older psychiatric outpatients, prevalence ratesbetween 5% and 33% have been reported and the prevalenceof (comorbid) PDs in older psychiatric inpatients has beenestimated between 7% and 80% (Van Alphen et al., 2012).These rates represent significant problems, because PDs inold age are associated with a lower quality of life andimpaired relationships (Segal et al., 2006), greater psychiatriccomorbidity (Schuster et al., 2013), and more medical treat-ment (Friedman et al., 2013). It is critically important to

detect PDs in older people because there is accumulatingevidence for the efficacy of psychotherapeutic treatment ofPDs in adults (Cristea et al., 2017; Dixon-Gordon et al.,2011; Stoffers et al., 2012). Recently, two studies have sup-ported the efficacy of schema therapy for reducing PDsymptoms in older adults. Such findings have increasedoptimism among those working with patients with PDs inlater life (Videler et al., 2014; Videler et al., 2018).

Because the age neutrality of many DSM PD criteria canbe considered doubtful (Balsis et al. [2007] estimated that 29%of criteria display measurement bias), two age-specific person-ality measurement instruments have been developed for assess-ing PDs in geriatric psychiatry (Rossi et al., 2014). The firstone is the Hetero-Anamnestische Persoonlijkheidsvragenlijst(Informant Personality Questionnaire; HAP; Barendse et al.,2013), which is a Dutch informant questionnaire. The HAPitems are based on detecting premorbid maladaptive anddysfunctional personality traits in retrospect. The psycho-metric properties of the HAP are good (see Barendse et al.,2013). The second age-specific instrument is the DutchGerontological Personality Disorders Scale (GPS; vanAlphen et al. 2006). The GPS is a screening instrument usedto detect PDs in older adults, and thus more generally cap-tures the presence of PD pathology. The GPS consists of

CONTACT Barbera E. van Reijswoud bvanreijswoud@derooysewissel.nl FPP “De Horst,” Heerderweg 25, 6224 LA Maastricht, The Netherlands.� 2020 Taylor & Francis Group, LLC

JOURNAL OF PERSONALITY ASSESSMENThttps://doi.org/10.1080/00223891.2020.1743710

both a patient version and an informant version. Sensitivityand specificity of the GPS in samples of older adults both inpsychiatric and general practice populations have beenreported to be reasonably good (Penders et al., 2015; VanAlphen et al., 2006). Although these two instruments can beused to screen for personality pathology in later life, neitherwere developed or validated for the use of detecting changesin components of personality functioning, for instance dueto treatment, and hence cannot be used for assessing treat-ment efficacy in terms of personality functioning.

The alternative model for PDs in Section III of theDSM–5 differentiates the severity of impaired personalityfunctioning (Criterion A) from the presence of maladaptivepersonality traits (Criterion B). Criterion A is defined asimpairment in the self and in the capacity for interpersonalfunctioning, which is dimensionally based. These core com-ponents of personality dysfunction have been found to dis-criminate between patients with and without a (traditionallydiagnosed) PD (Berghuis et al., 2013). Criterion A describesa dimensional view of personality functioning. Indeed, thisview fits with the finding that dimensional models are moreuseful than categorical ones for assessing dysfunctional traitsand behavior patterns in older people with PDs (VanAlphen et al., 2013), because assessment of dimensionaltraits has been found to be less age biased (Oltmanns &Balsis, 2011). It should be noted, though, that not allresearchers support the dimensional model (see, e.g., Shedleret al., 2010) but instead favor the traditional categor-ical model.

The Severity Indices of Personality Problems (SIPP–118;Viersprong, 2006) and its short form (SIPP–SF; Verheulet al., 2008) is a promising instrument for assessing DSM–5Criterion A (Bastiaansen et al., 2013). The SIPP was devel-oped to differentiate between normal and clinical popula-tions and to measure structural personality changes intreatment studies. The instrument provides a set of five reli-able and valid indexes of core components of (mal-) adap-tive personality functioning that seems to be sensitive tochange following treatment of patient populations (Johansenet al., 2016). The SIPP–118 has also shown to be a promis-ing instrument for measuring personality pathology in ado-lescents (Feenstra et al., 2011). One main caveat, however, isthat the SIPP–118 has not been formally validated in olderadults. Moreover, self-report questionnaires that include alarge number of items and detailed semistructured inter-views are relatively time-consuming and intensive for olderadults (Van Alphen et al., 2006). For these reasons, shorterversions of self-report questionnaires are preferable in old-age psychiatry and clinical geropsychology. The SIPP–SF hasabout half the number of items of the SIPP–118 (i.e., 60items instead of the original 118), and it has been found toshow good psychometric properties in a community samplewith an overall mean age of 25 years (Ro & Clark, 2009).

Notably, two studies in community-dwelling older adultsdemonstrated the utility of the SIPP–SF. The first studydemonstrated the construct validity of the SIPP–SF in botholder and younger adults by demonstrating a factorial struc-ture of five higher order domains (Rossi et al., 2017). In

older adults, personality functioning, as measured by theSIPP–SF, was more strongly associated with pathologicaltraits of the alternative model for PDs (namely psychoticism,disinhibition, antagonism, and dissocial behavior) than inyounger adults. The second study showed that the SIPP–SFwas an age-neutral instrument for measuring three out offour domains (self-control, identity integration, and socialconcordance) of personality functioning that closely corres-pond to Criterion A of DSM–5. The SIPP–SF domains ofself-control and identity integration capture the self-dimen-sion, whereas the SIPP–SF domains social concordance andrelational functioning capture the interpersonal dimensionas represented by the levels of personality functioning of theDSM–5 Section III model (Debast et al., 2018). In both thesestudies, the SIPP–SF was compared with instruments thatmeasure PDs as described in DSM–5 Section III, yet no pre-vious study used a categorical instrument for assessing DSMSection II PDs, like the Structured Clinical Interview forDSM–IV Axis II personality disorders (SCID–II; Firstet al., 1997).

Because the SIPP appears to be a useful instrument formeasuring personality pathology among adolescents andadults, it is important to investigate the utility of this instru-ment among older adults because this would offer an oppor-tunity to measure core components of personality across thelife span. The SIPP–SF seems to be a promising instrumentto measure the core components of personality functioningin older adults and to measure changes in personality func-tioning due to treatment. Because research on the reliabilityand validity of the SIPP–SF in older adults is limited, andcompletely lacking in clinical samples, the aim of this studywas to investigate the psychometric properties of theSIPP–SF in a clinical sample of older adults, namely psychi-atric outpatients in the Netherlands. We examine (a) thereliability of the five domains of the SIPP–SF; (b) the criter-ion validity of the SIPP–SF by comparing scores on theSIPP–SF between patients with and those without a SCID–IIPD diagnosis and assessing the nonredundant contributionof the scales in discriminating individuals with and withoutPDs; (c) associations between severity of personality path-ology as measured by the SIPP–SF and DSM Section II PDsas measured by the SCID–II (categorical and dimensional);(d) the convergent validity with the SIPP–SF and instru-ments developed specifically for assessing personality path-ology in older adults, by relating scores on the SIPP–SF withscores on the HAP and GPS; and (e) associations betweenSIPP–SF scores and psychiatric symptomatology as meas-ured by the Brief Symptom Inventory (BSI; Derogatis, 1975).

Method

Participants

Patients were recruited from two mental health institutes inthe Netherlands. The first sample was collected at the old-age Psychiatry Department of Mondriaan, including theClinical Center of Excellence for Personality Disorders inOlder Adults. The second sample was collected atPersonaCura, an expertise center for PDs in later life of

2 VAN REIJSWOUD ET AL.

Mental Health Center Breburg. The Medical Ethics ReviewCommittee Zuyderland-Zuyd (METC-Z) gave approval forthe research. The exclusion criteria were severe cognitiveproblems or dementia (defined as a Mini-Mental StateExamination score � 24/30), severe psychotic or bipolarproblems, significant intellectual problems (an IQ measuredor estimated as below 80), and the presence of alcohol ordrug addiction or use during testing. In Sample 1, eightpatients did not meet the criteria (too young, low intelli-gence, or withdrawing informed consent later on), resultingin 99 older adult patients with a diverse range of psychiatricproblems, all of whom had at least one DSM–5 classification.In Sample 2, there were nine patients who did not meet thecriteria (too young), resulting in 25 older adult patients whowere referred for personality problems to Breburg MentalHealth Center, as can be seen in Table 1. At the old-agePsychiatry Department of Mondriaan, the assessment batteryincluded the SCID–II, SIPP–SF, HAP, GPS, and BSI. AtBreburg, the same instruments were used with the exceptionof the BSI, which was not included. Of Sample 1, four par-ticipants did not complete the BSI. In both samples, 12 par-ticipants did not complete in the GPS. In 42 cases noinformant was available for the informant questionnaire(HAP). In both samples, gender was more or less equallydivided, the majority was of average education, and mostparticipants were married or living together. See Table 1 forfurther demographic information.

Instruments

The SIPP–SF (derived from the SIPP–118; Verheul et al.,2008; available online at https://www.deviersprong.nl/over-de-viersprong/over-de-viersprong-onderzoek/onderzoekslijn-diagnostiek/onderzoekslijn-assessment-en-indicatiestelling/sipp-main-menu/) is a short form of the SIPP, developedin the Netherlands. The SIPP–SF is a 60-item dimensionalself-report measure for the severity of personality path-ology (i.e., severity indexes of levels of personality func-tioning) that was specifically developed for treatmentoutcome research. Items measure the core components ofmaladaptive personality functioning with five higher orderdomains (self-control, identity integration, relationalcapacities, responsibility, and social concordance).

Respondents indicate the extent to which they agree withstatements over a time frame of the last 3 months. Theresponse categories range from 1 to 4 and are described asfully disagree, partly disagree, partly agree, or fully agree. Anexample of an item from the self-functioning scale is“Sometimes I get so overwhelmed that I can’t control myreactions.” An example of an item from the interpersonalfunctioning scale is “I tend to think of myself as a loner.”The scores are clustered into five domains, with higherdomain scores indicating more adaptive functioning andlower scores indicating more maladaptive personality func-tioning. In a prior study, Cronbach’s alpha values rangedfrom a ¼ .83 (social concordance) to a ¼ .89 (self-controland identity integration; Ro & Clark, 2009).

The Dutch version of the SCID–II (First et al., 1997;Weertman et al., 2000) was used to formally diagnoseDSM–5 Section II PDs. The SCID–II is a semistructuredinterview that includes coverage of all 10 specific DSM–5PDs as well as PD not otherwise specified (other specifiedPD in DSM–5). The interview contains 134 open-endedquestions and begins with questions about behavior andrelationships of the patient. Thereafter, items assess the diag-nostic criteria for each of the 10 standard PDs, organizedone by one. For example, the SCID–II consists of questionslike these: “When you are out in the public and see peopletalking, do you often feel that people are talking aboutyou?” Each PD criterion is rated as 1 (absent or false), 2(subthreshold), or 3 (threshold or true). In this study, allclinicians conducting SCID–II interviews were extensivelytrained to ensure the quality of interviewing. The trainingwas provided by the main researcher by giving oral educa-tion about the instrument to the clinicians individually in60-min sessions. Subsequently, all clinicians observed twointerviews done by an experienced interviewer, and then allclinicians performed two interviews under supervisionbefore doing the interviews independently. The mainresearcher was available for consultation for the cliniciansduring the study. The SCID–II has shown good interraterreliability for the presence or absence of a PD in previousresearch (Lobbestael et al., 2011), especially among trainedinterviewers.

The Dutch HAP (Barendse et al., 2013) is an informantquestionnaire with items that are based on detecting

Table 1. Overview of the samples, with a total of n¼ 124 participants.

Sample

1 2

n 99 25% female 51.5 60.0Mean age (SD) 70.6 (5.3) 66.9 (4.6)% educational levelLow 20.2 20.0Average 53.5 56.0High 26.3 24.0

% marital statusMarried/living together 68.7 58.3Single/divorced/widow(er) 31.3 41.7Assessment battery SCID–II, SIPP–SF, HAP, GPS, BSI SCID–II, SIPP–SF, HAP, GPS

Note. SCID–II¼ Structured Clinical Interview for DSM–IV Axis II Personality Disorders; SIPP–SF¼ Severity Indices ofPersonality Problems–Short Form; HAP¼Hetero-Anamnestische Persoonlijkheidsvragenlijst (Informant PersonalityQuestionnaire); GPS¼Gerontological Personality Disorders Scale; BSI¼ Brief Symptom Inventory.

SIPP–SF IN OLD AGE PSYCHIATRY 3

premorbid maladaptive personality traits. The HAP wasdeveloped and validated for use in old-age psychiatry andnursing homes. The HAP consists of 62 items that are retro-spectively assessed. Scores are provided on 10 scales: SociallyAvoidant Behavior, Uncertain Behavior, Vulnerability inInterpersonal Relationships, Somatizing Behavior, DisorderlyBehavior, Rigid Behavior, Perfectionistic Behavior,Antagonistic Behavior, Self-Satisfied Behavior, andUnpredictable and Impulsive Behavior. There are four scalesto check validity of responding. There are three responsecategories: yes, more or less, and no. In the instructions ofthe HAP, a distinction is made between current psychiatricsymptoms or problems and the person’s premorbid person-ality. The psychometric qualities of the HAP are good. Theinternal consistency of the 10 scales is good (as ¼ .63–.85,Akaike’s information criterion [AICs] ¼ .23–.53); the inter-rater and test–retest reliabilities are good to excellent (inter-class correlation coefficients [ICCs] ¼ .60–.98); and theconstruct validity, as evidenced through factor analyses,showed the same factor structure in both nursing home resi-dents and older adult psychiatric patient populations(Barendse et al., 2013). In this study, Cronbach’s alpha val-ues ranged from a ¼ .44 (unacceptable) to .80 (good).Additionally, the average interitem correlations (AIC) werecalculated to correct for the small numbers of items in thesubscales. An AIC above .15 is considered to be acceptable(Clark & Watson, 1995). All AICs were above .15, specific-ally ranging from .15 (Rigid Behavior) to .47 (SomatizingBehavior). Descriptive statistics for the HAP are provided inTable 2.

The GPS (Van Alphen et al., 2006) is a screening instru-ment to detect PDs in older adults. The GPS consists of apatient version and an informant version. Both versionsconsist of two scales: habitual behavior (GPS-HAB) and bio-graphical information (GPS-BIO). The GPS-HAB scaleassesses habitual behaviors that reflect the expression of anumber of PD features. In the GPS-BIO scale important andrecurrent events or decisions in life are linked to the pres-ence or absence of DSM–5 PDs. The internal consistency(Cronbach’s alpha) of the two scales ranges from poor(GPS-HAB a ¼ .57) to acceptable (GPS-BIO a ¼ .77; VanAlphen, 2006). The test–retest reliability of the GPS-HABand the GPS-BIO subscales were moderate (Spearman’s r ¼.72) and excellent (Spearman’s r ¼ .89), respectively.Sensitivity and specificity of the GPS patient version in anolder psychiatric outpatient population was shown to be fairwith sensitivity and specificity levels around 70% (VanAlphen et al., 2006). In this study, only the GPS patient ver-sion was used.

In this study, Cronbach’s alpha for the total score wasa ¼ .71 (acceptable), for the GPS-HAB scale a ¼ .52 (poor),and for the GPS-BIO a ¼ .71 (acceptable). In addition, theaverage interitem correlation (AIC) was calculated for thesubscales to correct for the different numbers of items inthe subscales. AICs were .14 (GPS-HAB) and .20 (GPS-BIO). The AIC of the GPS-BIO scale was above the min-imum level of .15 (Clark & Watson, 1995). Descriptive sta-tistics for the GPS are provided in Table 2.

The Dutch version of the BSI (Derogatis, 1975; translatedby De Beurs, 2006) was used to measure symptomatic dis-tress. The BSI consists of 53 self-report items covering ninesymptom dimensions: somatization, obsession-compulsion,interpersonal sensitivity, depression, anxiety, hostility, pho-bic anxiety, paranoid ideation, and psychoticism. The BSIalso contains three global indexes of distress: PositiveSymptom Distress Index, Positive Symptom Total, andGlobal Severity Index (GSI). Only the GSI was used in thisstudy. The GSI is a measurement for overall psychologicaldistress reflecting the average score of all item responses.Scores range from 1 to 5, with higher scores indicating ahigher level of psychological and emotional distress. TheGSI was used because it integrates all scales with differentkinds of symptoms and it is useful for measuring symptom-atic distress for patients with diverse psychopathology asincluded in our study. A sample item on this measure is“feeling no interest in things.” Respondents rate each itemfor the past 7 days on a 5-point Likert scale: 0 (not at all), 1(a little bit), 2 (moderately), 3 (quite a bit), and 4(extremely). Reliability of the Dutch version is good(Cronbach’s a ¼ .71–.85) and the factorial structure is com-parable to that of the original version (De Beurs, 2006). Inthis study, Cronbach’s alpha of the GSI scale was excellent(a ¼ .97). Descriptive statistics for the GSI are provided inTable 2.

Statistical analyses

All statistical analyses were performed using SPSS 22.0.First, the internal reliability of the SIPP–SF scores was ana-lyzed using Cronbach’s alpha, AIC, and interscale Pearsoncorrelations (effect size r). Second, criterion validity of theSIPP–SF between patients with and those without a PD, asassessed by the SCID–II, was tested with independent sam-ple t tests. Bonferroni correction was used to correct forfamilywise error rates. The significance level for the analyseswas set at p ¼ .01 (.05/5). Effect sizes were computed byCohen’s d. In addition, to examine the value of the SIPP–SF

Table 2. Descriptive statistics for the HAP, GPS and BSI.

Scale Minimum Maximum M SD Variance

HAP SOC .00 10.00 2.96 2.73 7.42UNC .00 10.00 3.64 2.89 8.33VUL .00 12.00 5.83 3.31 10.95SOM .00 8.00 2.46 2.49 6.18DIS .00 8.00 2.19 2.41 5.82RIG .00 8.00 3.77 2.08 4.32PER .00 8.00 4.24 2.40 5.77ANT .00 18.00 6.09 4.04 16.34SEL .00 10.00 2.27 2.07 4.29UNP .00 12.00 4.17 3.17 10.08

GPS BIO .00 8.00 3.83 2.15 4.77HAB .00 7.00 3.00 1.68 2.81Total score .00 14.00 6.83 3.15 9.91

BSI GSI .02 3.43 1.30 .83 .68

Note. HAP¼Hetero-Anamnestische Persoonlijkheidsvragenlijst (InformantPersonality Questionnaire); GPS¼Gerontological Personality Disorders Scale;BSI¼ Brief Symptom Inventory; SOC¼ Socially Avoidant Behavior;UNC¼Uncertain Behavior; VUL¼ Vulnerability in Interpersonal Relationships;SOM¼ Somatizing Behavior; DIS¼Disorderly Behavior; RIG¼ Rigid Behavior;PER¼ Perfectionistic Behavior; ANT¼Antagonistic Behavior; SEL¼ Self-Satisfied Behavior; UNP¼Unpredictable and Impulsive Behavior.

4 VAN REIJSWOUD ET AL.

scales in predicting the presence or absence of PDs, a binarylogistic regression analysis was conducted. Third, associa-tions between severity of personality pathology as measuredby the SIPP–SF and by the SCID–II (categorical, as in num-ber of diagnosable PDs and dimensional, as in the numberof endorsed PD criteria) were analyzed by Pearson correla-tions (effect size r). Fourth, convergent validity of theSIPP–SF was evaluated by calculating Pearson correlations(effect size r) between the SIPP–SF and both the HAP scalesand GPS scores. Finally, Pearson correlations (effect size r)were calculated to evaluate associations between SIPP–SFdomain scales and psychiatric symptomatology using theGSI scale of the BSI.

Results

The SCID–II findings showed that 93 participants werediagnosed with one or more PD(s), whereas 31 participantswere not diagnosed with a PD. This means that 75% of theparticipants were diagnosed with one or more PD(s). About40% had one PD, and 34.6% had two or more PDs. In thepercentage of cases of PDs, the other specified PD (OSPD)was the most common diagnosis (60.5%). The most com-mon specific PD diagnosis was obsessive-compulsive PD(16.9%), followed by borderline PD (14.5%), avoidant PD(13.7%), antisocial PD (7.3%), dependent PD (5.6%), narcis-sistic PD (4.0%), paranoid PD (3.2%), and schizoid PD andschizotypal PD (both 0.8%). No diagnosed cases of histrionicPD were found. Subsamples with specific PDs were toosmall to allow statistics for specific PDs. Therefore, thebroad distinction between having a PD or not was used infurther analyses. Besides PDs, several comorbid psychiatricproblems were present in the sample. Specifically, the num-ber of non-PD DSM–5 diagnoses varied from none to five.The most common diagnosis was depressive disorder.

Research Question 1: Internal reliability ofSIPP–SF scores

The five domains of the SIPP–SF scores showed Cronbach’salpha values ranging from a ¼ .75 to .91 with a mean esti-mated alpha value of a ¼ .82 (see Table 3). The AIC rangedfrom .20 (relational capacities) to .46 (identity integration),with a mean AIC of .31. These values indicate acceptable toexcellent reliability of all the domain scales. Intercorrelationsbetween the domains ranged from r ¼ .39 (between identity

integration and social concordance) to .75 (between self-control and social concordance), with a median correlationof r ¼ .51 (see Table 4). These positive correlations ofmedium and large effect sizes confirm the general homogen-eity of the SIPP–SF.

Research Question 2: The criterion validity bycomparing scores on the SIPP–SF between patientswith and those without a SCID–II PD diagnosis

The SIPP–SF scores on all domains showed statistically sig-nificant differences, at the .01 level, between patients withand without a PD, showing that patients with a PD scoredlower on all scales compared to those without a PD (notethat lower scores reflect greater maladaptive personalityfunctioning). Effect sizes (d) ranged from .59 (social con-cordance) to .86 (relational capacities), indicating moderateto large differences, as can be seen in Table 3. Next, logisticregression was performed to assess the nonredundant impactof the SIPP–SF scales on the likelihood that the patient hada PD. The model for the SIPP–SF contained all five scales aspredictor variables. A total of 124 cases were analyzed, andthe full model significantly predicted the PD status: omnibusv2(5) ¼ 23.346, p < .000; Hosmer & Lemeshow v2(8) ¼16.805, p < .05. The model accounted for between 10.3%and 18.0% of the variance in the PD status, and successfullypredicted 93.5% of the patients with PDs. In contrast, almosthalf (41.9%) of the predictions of patients without PDs wereaccurate. Overall, 80.6% of the predictions were correct, incomparison to 75.0% in the model only including the con-stant. Table 5 shows the coefficients, Wald statistic, andprobability values for each of the predictor variables. Thesevalues show that none of the SIPP–SF scales showed non-redundant contributions in predicting the PD status.

Research Question 3: Severity of personality pathology

As can be seen in Table 6, the number of DSM–5 PD crite-ria was negatively associated with SIPP–SF domains(medium effect sizes), showing a relationship betweenendorsed PD criteria and greater impairment of personalityfunctioning. This was also seen for the number of pre-sent PDs.

Table 3. Mean domain scores and standard deviations of patients without personality disorder (PD) and patients with PD as measured by the SCID–II, independ-ent t tests and effect size (d).

Sample

Patients without PD (n¼ 31) Patients with PD (n¼ 93)

Domain Cronbach’s alpha M SD M SD t(134) Effect size (d)

Self-control .86 3.37 0.61 2.84 0.64 4.04� .84Identity integration .91 3.12 0.75 2.52 0.75 3.92� .81Responsibility .79 3.50 0.46 3.14 0.52 3.40� .72Relational capacities .75 3.06 0.52 2.61 0.53 4.02� .86Social concordance .79 3.35 0.47 3.04 0.55 2.80� .59

Note. Equal variances were assumed for all domains. SCID–II¼ Structured Clinical Interview for DSM–IV Axis II Personality Disorders.�p < .01 (using Bonferroni correction).

SIPP–SF IN OLD AGE PSYCHIATRY 5

Research Question 4: Convergent validity withpersonality pathology measures for older adults

All domain scores of the SIPP–SF correlated negatively withthe GPS total score and GPS-BIO scale score with small(social concordance), medium (self-control, responsibility,relational capacities), and large (identity integration) effectsizes, as can be seen in Table 6. For the GPS-HAB scalescore, the significant associations with self-control, identityintegration, and responsibility were of medium effect size,and with relational capacities of small effect size. The associ-ation with social concordance was nonsignificant for theGPS-HAB scale score.

Regarding the HAP, the majority of HAP scales did notsignificantly correlate with the SIPP–SF domains, as can beseen in Table 6. Only one scale of the HAP, Unpredictableand Impulsive Behavior, correlated negatively with allSIPP–SF domains, yet only two correlations showed amedium effect (self-control and social concordance). TheHAP scale Antagonistic Behavior correlated negatively withthree SIPP–SF domains, showing a medium effect (self-con-trol, relational capacities, and social concordance).

Research Question 5: Associations with psychiatricsymptomatology

The domain scores of the SIPP–SF were not significantlycorrelated with the GSI scale of the BSI, as can be seen inTable 6.

Discussion

The overarching aim of this study was to investigate thepsychometric properties of the SIPP–SF for assessing com-ponents of personality functioning among older adult psy-chiatric outpatients in the Netherlands. We found anacceptable to excellent internal consistency of all fiveSIPP–SF domain scores in this sample. For all SIPP–SF

domains, a statistically significant difference was foundbetween patients with and those without a PD, as classifiedwith the SCID–II. More specifically, patients with a PDscored lower on all SIPP–SF scales compared to those with-out a PD, which was expected as lower SIPP–SF domainscores reflect greater maladaptive personality functioning.Furthermore, the SIPP–SF showed good criterion validity inpredicting a PD. This implies that the SIPP–SF canadequately differentiate between patients with and without aPD and that SIPP–SF scales are meaningfully related to per-sonality pathology among older adult outpatients. Also, theSIPP–SF scales were associated with the severity of personal-ity pathology, given the negative correlations of the scaleswith the number of PDs and with the number of DSM–5PD criteria. Moreover, all SIPP–SF domains correlated withthe GPS-BIO subscale and total score of the GPS patientversion, a screening instrument for PDs in older adults.However, the GPS-HAB scale failed to show significant cor-relations with the social concordance subscale. One possibleexplanation for this finding might be that the majority ofpeople with PDs are unaware of the effect their behavior hason others (Klonsky et al., 2002).

The SIPP–SF did not correlate with most scales of theHAP. An explanation might be that the HAP is filled in byan informant and not by participants themselves. Researchhas shown that the informant sees a person and his or herpathology different than the participant sees himself or her-self. This can be due to a lack of insight that a person hasin the effect of one’s behavior on others. Another possibleexplanation might be the unwillingness to disclose on aquestionnaire or in an interview (Cruitt & Oltmanns, 2018).The scales from the HAP (ANT and UNP) that showed anegative correlation with medium effect with some, but notall, domains of the SIPP–SF, are scales that belong to the“impulsive and frustration tolerance” profile (Barendse &Thissen, 2006). For this profile, it is described that mostinformants experience this behavior as egocentric andunpleasant and high scores might indicate an antisocial, bor-derline, or passive-aggressive PD (Barendse & Thissen,2006). This corresponds with the finding that self–informantconcordance on PD traits is highest for Cluster B pathology,excluding narcissism (Klonsky et al., 2002) and this mightexplain the correlations on these specific scales (ANT andUNP) with the SIPP–SF. In addition, the HAP uses a lot ofbehavior descriptions, whereas the SIPP–SF includes ques-tions about feelings and cognitions about oneself and otherpersons. Thus, the use of different kinds of questions in theinstruments might measure different aspects of personality.

Contrary to our expectations, no correlations were foundbetween the BSI GSI and the SIPP–SF domain scores. This

Table 4. Pearson correlations of the Severity Indices of Personality Problems–Short Form scales.

Self-control Identity integration Responsibility Relational capacities Social concordance

Self-control —Identity integration .60�� —Responsibility .50�� .51�� —Relational capacities .55�� .61�� .41�� —Social concordance .75�� .39�� .44�� .53�� —

Note. N¼ 124.��Correlations are significant at the .01 level.

Table 5. Logistic regression analyses predicting the likelihood of having a per-sonality disorder based on the Severity Indices of Personality Problems–ShortForm (SIPP–SF) scales.

SIPP–SF scales B SE Wald p Exp (B) 95% CI

Self-control �.812 .641 1.605 .205 .444 [.126, 1.560]Identity integration �.246 .441 .312 .576 .782 [.330, 1.854]Responsibility �.663 .591 1.259 .262 .516 [.162, 1.640]Relational capacities �.832 .573 2.109 .146 .435 [.142, 1.338]Social concordance .250 .731 .117 .732 1.285 [.307, 5.381]Constant 8.093 2.134 14.383 .000 3270.547

Note. df¼ 1. Reference category of the dependent: no personality disorder.Nagelkerke’s R2 ¼ .254.

6 VAN REIJSWOUD ET AL.

means that personality pathology as measured by theSIPP–SF was not associated with overall psychological dis-tress as measured with the BSI GSI. This is in contrast withthe work of Feenstra and colleagues (2011), who foundmeaningful correlations between the SIPP–118 and the GSIscale of the Symptom Checklist–90 (from which the BSI isderived) in adolescents. The variance of the GSI scoreshowed no evidence for restricted range that would impedethe correlation coefficient. One reason for this discrepancycan be that the study of Feenstra et al. (2011) used a moreheterogeneous sample comprising high school students andinpatients in addition to outpatients. In a more heteroge-neous sample, psychiatric symptoms are expected to showmore variation due to lower and higher symptomatology,respectively. Alternatively, the absence of correlationsbetween the SIPP–SF and GSI might indicate that theSIPP–SF is not greatly influenced by having other psychi-atric symptomatology, at least in this sample with high ratesof PDs. It is possible that, in the absence of a PD, theSIPP–SF is more sensitive to psychological distress. Furtherresearch with inpatient and nonpatient samples is needed toclarify this issue.

Our findings, however, indicate that the SIPP–SF is over-all a good instrument to assess the severity of impaired per-sonality functioning in older adult outpatients. Notably, itcan differentiate between having a PD or not. The import-ance of detecting PDs in old age has become increasinglyimportant because there is recent evidence of the efficacy ofschema therapy for reducing PD symptoms in older adults(Videler et al., 2014; Videler et al., 2018). The SIPP–SF is arelatively short instrument (60 questions vs. 118 in the fullversion) and it is known that many older patients have diffi-culties with long instruments (Rossi et al., 2014). As such,

the SIPP–SF might be called an older adult “friendly” instru-ment for PDs.

Several strengths of this study should be noted. First,this study included a relatively large sample for researchwith older adult outpatients. Studies in older adults areknown for high dropout rates and recruitment difficulties(Provencher et al., 2014). Moreover, there was a high rateof PDs in our sample. Our total sample consisted of 124older patients, of whom 75% were diagnosed with a PD.This high rate of PDs can be explained by the fact that inone sample (Breburg) only participants with a suspectedPD were included, and both participating psychiatric insti-tutions are expertise centers for PDs in older adults.Therefore, more people with PDs are likely referred toboth institutions. This prevalence rate, however, is withinthe limits described by Van Alphen et al. (2012). Second, itwas a strength that, in this study, almost all specific PDswere represented, except histrionic PD. Nevertheless, thenumber of specific PDs was too small for further statisticalanalyses and only the distinction between having a PD ornot was used in our analyses, therefore causing no problemfor absence or overrepresentation of specific PDs. Third, itwas a strength that the SIPP–SF was investigated withinstruments that are known to be applicable for olderadults, like the BSI, or specifically designed for age-specificpersonality assessment in old age, like the GPS and theHAP (Rossi et al., 2014). The final strength was the factthat we compared two clinical groups of older psychiatricoutpatients, one with a PD and one without a PD. Bothclinical groups thus experienced general psychiatric dis-tress. Due to differentiation and comparison of thesegroups, we decreased the odds that the SIPP–SF is measur-ing general psychiatric distress.

Table 6. Pearson correlations between the Severity Indices of Personality Problems–Short Form (SIPP–SF) domain scores and the number of personality disorder(PD) criteria and number of diagnosable PDs, Gerontological Personality Disorders Scale (GPS) scales, Hetero-Anamnestische Persoonlijkheidsvragenlijst (InformantPersonality Questionnaire; HAP) dimensions, and Global Severity Index (GSI) subscale of the Brief Symptom Inventory (BSI).

SIPP–SF domains

Self-control Identity integration Responsibility Relational capacities Social concordance

SCID–II (n¼ 124)Number of PD criteria �.44��� �.30�� �.30�� �.37��� �.44���Number of diagnosable PDs �.50��� �.38��� �.38��� �.42��� �.49���

GPS (n¼ 112)BIO score �.35�� �.53�� �.36�� �.40�� �.21�HAB score �.38�� �.42�� �.43�� �.29�� �.18

Total score �.44�� �.60�� �.47�� �.44�� �.24��HAP (n¼ 82)SOC �.21 �.16 �.15 �.28�� �.29��UNC �.03 �.03 �.04 .02 .07VUL �.28� �.11 �.08 �.10 �.27��SOM �.13 .08 .17 .15 �.01DIS .03 .01 �.19 �.10 �.01RIG �.19 �.15 .04 �.10 �.16PER �.01 �.01 .18 �.02 �.06ANT �.38�� �.15 �.13 �.30�� �.49��SEL �.20 �.17 �.10 �.19 �.24�UNP �.46�� �.25� �.23� �.27�� �.45��

BSI GSI (n¼ 95) �.15 �.14 .01 �.09 �.07

Note. SOC¼ socially avoidant behavior; UNC¼ uncertain behavior; VUL¼ vulnerability in interpersonal relationships; SOM¼ somatizing behavior; DIS¼ disorderlybehavior; RIG¼ rigid behavior; PER¼ perfectionistic behavior; ANT¼ antagonistic behavior; SEL¼ self-satisfied behavior; UNP¼ unpredictable and impul-sive behavior.�Correlation is significant at the p < .05 level (2-tailed).��Correlation is significant at the p < .01 level (2-tailed).��� Correlation is significant at the p < .001 level (2-tailed).

SIPP–SF IN OLD AGE PSYCHIATRY 7

Despite many strengths, several important limitationswere present. First, our sample did not include participantsfrom the general population, where psychiatric symptomsare expected to be lower, or inpatients, where psychiatricsymptoms are expected to be acute and higher. This mighthave given a different view on the associations with symp-tomatic distress. Second, some items of the SIPP–SF thatrefer to work can be perceived as “not suitable” to someolder people. For instance, in the SIPP–SF one question is,“At work I get easily irritated about other people’s ways ofdoing things.” One can argue whether these items should berewritten to general situations for use with older adults tocapture all components of personality pathology in later life.Moreover, the domain “relational capacities” was found tolack age-neutrality in recent research due to a differentdegree of expression of the same underlying construct in theolder age group (Debast et al., 2018). Third, the GPS-HABscale showed poor internal consistency in this sample. Thispoor internal consistency might be explained by the factthat the GPS-HAB scale assesses habitual behaviors and con-sists of a short list of expressions that relate to behaviorlinked to various PDs and therefore the items are not neces-sarily correlated. Fourth, one benefit of the SIPP is that it isdesigned to capture personality change during treatment,but follow-up data were not assessed in this study. It istherefore a limitation of this study that test–retest reliabilitywas not obtained, and this should be evaluated in futureresearch. A final limitation was that we did not includeinterrater reliability for the SCID–II diagnoses. Althoughour raters were highly trained, formal interrater reliabilityshould be established.

Conclusion

The SIPP–SF is a highly promising instrument to be used ingeriatric psychiatry and clinical geropsychology for themeasurement of core components of (mal)adaptive personal-ity pathology. Two main advantages of the SIPP–SF forapplication in later life are the relatively short form of theinstrument, which makes it more suitable for use in olderadults, and the close correspondence with the concept of theseverity of impaired personality functioning as operational-ized in Criterion A of DSM–5 Section III. After all, treat-ment of PDs primarily aims at improving personalityfunctioning. The best way of assessing improvement in per-sonality functioning is by using an instrument that isdesigned to measure this construct, such as the SIPP–SF.Several research questions remain to be answered. For clin-ical use of the SIPP–SF, a cutoff score for the domainsmight be useful to indicate pathological personality func-tioning. Furthermore, as the SIPP–118 is known to be ableto measure the treatment efficacy for PDs in both adultsand adolescents (Feenstra et al., 2011; Verheul et al., 2008),further research on the capability of the SIPP–SF to assesstreatment effects in older adults is desirable. Hopefully, ourresults will stimulate further research on older adults withPDs, and on the formal assessment of personality

functioning among older adults with varying degrees ofPD symptoms.

ORCID

Arjan C. Videler http://orcid.org/0000-0002-2175-3453

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