Muirne C. S. Paap

Psychiatric characteristics in transsexual individuals: multicentre study in four European countries

BACKGROUND Research into the relationship between gender identity disorder and psychiatric problems has shown contradictory results. AIMS To investigate psychiatric problems in adults fulfilling DSM-IV-TR criteria for a diagnosis of gender identity disorder. METHOD Data were collected within the European Network for the Investigation of Gender Incongruence using the Mini International Neuropsychiatric Interview - Plus and the Structured Clinical Interview for DSM-IV Axis II Disorders (n = 305). RESULTS In 38% of the individuals with gender identity disorder a current DSM-IV-TR Axis I diagnosis was found, mainly affective disorders and anxiety disorders. Furthermore, almost 70% had a current and lifetime diagnosis. All four countries showed a similar prevalence, except for affective and anxiety disorders, and no difference was found between individuals with early-onset and late-onset disorder. An Axis II diagnosis was found in 15% of all individuals with gender identity disorder, which is comparable to the general population. CONCLUSIONS People with gender identity disorder show more psychiatric problems than the general population; mostly affective and anxiety problems are found.

Intake of Own Mother's Milk during the First Days of Life Is Associated with Decreased Morbidity and Mortality in Very Low Birth Weight Infants during the First 60 Days of Life

Background: The incidence of necrotizing enterocolitis (NEC) and possibly also of sepsis is lower in preterm infants fed their own mother’s milk (hereafter ‘mother’s milk’) compared with formula-fed infants. It is unclear whether this is caused by the protective properties of breast milk or by the absence of cow’s milk. Especially in early life, mother’s milk is often unavailable to preterm infants, while minimal enteral nutrition is initiated immediately. Objectives: To determine whether there is an association between intake of mother’s milk during the first days of life and the combined outcome of sepsis, NEC and death over a prolonged period. Methods: Retrospective study in infants with a birth weight <1,500 g. Intake of mother’s milk and formula during the first 10 days of life was recorded. The occurrence of sepsis, NEC and death was registered during the first 60 days. Data were analysed using Cox regression analysis, taking confounders into account. Results: In total, 349 infants were included. Intake of mother’s milk during the first 5 days of life was associated with a lower incidence of NEC, sepsis and/or death during the first 60 days of life (hazard ratio (HR) in the category 0.01–50% intake of mother’s milk: 0.49, 95% confidence interval (CI) 0.28, 0.87; HR in the category 50.01–100% intake of mother’s milk: 0.50, 95% CI 0.31, 0.83, both compared to no mother’s milk). During days 6–10, the protective effect was only present if >50% of the total intake was mother’s milk (HR = 0.37, 95% CI 0.22, 0.65). Conclusion: The type of enteral nutrition during the first 10 days of life is associated with the risk of NEC, sepsis and/or death during the first 60 days of life.

Rumination and Age: Some Things Get Better

Rumination has been defined as a mode of responding to distress that involves passively focusing ones attention on symptoms of distress without taking action. This dysfunctional response style intensifies depressed mood, impairs interpersonal problem solving, and leads to more pessimistic future perspectives and less social support. As most of these results were obtained from younger people, it remains unclear how age affects ruminative thinking. Three hundred members of the general public ranging in age from 15 to 87 years were asked about their ruminative styles using the Response Styles Questionnaire (RSQ), depression and satisfaction with life. A Mokken Scale analysis confirmed the two-factor structure of the RSQ with brooding and reflective pondering as subcomponents of rumination. Older participants (63 years and older) reported less ruminative thinking than other age groups. Life satisfaction was associated with brooding and highest for the earlier and latest life stages investigated in this study.

A study of the dimensionality and measurement precision of the SCL-90-R using item response theory

We used item response theory (IRT) to (a) investigate the dimensionality of the Symptom Checklist‐90‐Revised (SCL‐90‐R) in a severely disturbed patient group, (b) improve the subscales in a meaningful way and (c) investigate the measurement precision of the improved scales. The total sample comprised 3078 patients (72% women, mean age = 35 ± 9) admitted to 14 different day hospitals participating in the Norwegian Network of Personality‐focused Treatment Programmes. Mokken Scale Analysis was used to investigate the dimensionality of the SCL‐90‐R and improve the subscales. This analysis was theory‐driven: the scales were built on two start items that reflected the content of the disorder that corresponds with the specific scale. The Graded Response Model was employed to determine measurement precision. Our theory‐driven IRT approach resulted in a new seven‐factor solution including 60 of the 90 items clustered in seven scales: depression, agoraphobia, physical complaints, obsessive‐compulsive, hostility (unchanged), distrust and psychoticism. Most of the new scales discriminated reliably between patients with moderately low scores to moderately high scores. In conclusion, we found support for the multidimensionality of the SCL‐90‐R in a large sample of severely disturbed patients. Copyright

Why the factorial structure of the SCL-90-R is unstable: Comparing patient groups with different levels of psychological distress using Mokken Scale Analysis

Since its introduction, there has been a debate about the validity of the factorial structure of the SCL-90-R. In this study we investigate whether the lack of agreement with respect to the dimensionality can be partly explained by important variables that might differ between samples such as level of psychological distress, the variance of the SCL-90-R scores and sex. Three samples were included: a sample of severely psychiatrically disturbed patients (n=3078), a sample of persons with Gender Incongruence (GI; n=410) and a sample of depressed patients (n=223). A unidimensional pattern of findings were found for the GI sample. For the severely disturbed and depressed sample, a multidimensional pattern was found. In the depressed sample sex differences were found in dimensionality: we found a unidimensional pattern for the females, and a multidimensional one for the males. Our analyses suggest that previously reported conflicting findings with regard to the dimensional structure of the SCL-90-R may be due to at least two factors: (a) level of self-reported distress, and (b) sex. Subscale scores should be used with care in patient groups with low self-reported level of distress.

Identifying key domains of health-related quality of life for patients with Chronic Obstructive Pulmonary Disease: the patient perspective

BackgroundNumerous instruments are available to measure health-related quality of life (HRQoL) in patients with Chronic Obstructive Pulmonary Disease (COPD), covering a wide array of domains ranging from symptoms such as dyspnea, cough and wheezing, to social and emotional functioning. Currently no information or guide is available yet to aid the selection of domains for a particular study or disease population. The aim of this paper is to identify which domains of HRQoL are most important with respect to COPD, from the patient perspective.MethodsTwenty-one Dutch patients with COPD were asked to describe important domains impacted by COPD freely; second, they were presented with cues (domains from the Patient-Reported Outcomes Measurement Information System (PROMIS) framework) and were asked to select the domains that were most relevant to them. During the interview, the patients were asked to indicate in which way the selected domains impact their lives. Both the answers to the open question, and the patient statements motivating nomination of PROMIS domains were coded into themes.ResultsThe most relevant (sub)domains of HRQoL for patients with COPD were: physical health (fatigue, physical functioning), social health (instrumental support, ability to participate in social roles and activities, companionship, and emotional support), and coping with COPD.ConclusionWe identified which domains of HRQoL are most important to patients with COPD. One of these (coping with COPD) is not explicitly covered by PROMIS, or by traditional questionnaires that are used to measure HRQoL in COPD.

The Link between Peer Relations, Prosocial Behavior, and ODD/ADHD Symptoms in 7–9-Year-Old Children

Oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) are characterized by symptoms that hinder successful positive interaction with peers. The main goal of this study was to examine if the presence of symptoms of ODD and ADHD affects the relationship between positive social behavior and peer status found in 7–9-year-old children who show symptoms typical of ADHD and/or ODD. Furthermore, the possible interaction with sex was investigated. We used data collected in the first wave of The Bergen Child Study of mental health (BCS), a prospective longitudinal total population study of childrens developmental and mental health. The target population consisted of children in the second to the fourth, in all public, private, and special schools in Bergen, Norway, in the fall of 2002 (N = 9430). All 79 primary schools in Bergen participated in the study. Both teacher (8809 complete cases) and parent (6253 complete cases) report were used in the analyses. ADHD and ODD scores were estimated using the Swanson Noland and Pelham rating scale version IV (SNAP-IV), and peer problems and prosocial behavior were assessed using the Strengths and Difficulties Questionnaire (SDQ). We replicated the relationship between peer problems and prosocial behavior found previously in typically developing children. Our results showed that the relationship between peer problems and prosocial behavior became weaker as the ODD symptoms increased in number and severity. For ADHD this effect was only found in the teacher report of the children. A sex effect for ODD symptoms was found only using the parent report: boys with ODD symptoms showed less prosocial behavior than girls with similar levels of ODD symptoms. Since this effect was not found using the teacher data, it may imply a situational effect (school/home) for girls with high levels of ODD. The moderator effect of ODD/ADHD was comparable for boys and girls. Our findings suggest that even if children with ADHD/ODD symptoms have the opportunity to practice their social skills in peer relationships, this is not necessarily accompanied by an increase in prosocial behavior.

The St George's Respiratory Questionnaire revisited : A psychometric evaluation

PurposeThe St George’s Respiratory Questionnaire (SGRQ) has clearly acquired the status of legacy questionnaire for measuring health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). The main aim of this study was to assess the underlying dimensionality of the SGRQ and to investigate the added value of the empirical weights used to calculate total scores.MethodsThe official Dutch translation of the SGRQ was completed by 444 COPD patients participating in two clinical studies. These data were used for secondary data analysis in this study. Three complementary statistical methods were used to assess dimensionality: Mokken scale analysis (MSA), parametric multidimensional item response theory (IRT) and bifactor analysis. Additionally, the original SGRQ weighting procedure was compared to IRT-based weighting.ResultsThe results of the MSA and multidimensional item response theory (MIRT) pointed toward a unidimensional structure. The bifactor analyses indicated that there was a strong general factor, but the group factors did have additional value. Nineteen items performed poorly in the MSA, MIRT analysis or both. Shortening the scale from 50 to 31 items did not negatively impact measurement precision. SGRQ total score and IRT-derived scores correlated strongly, 0.90 for the one-parameter model and 0.99 for the two-parameter model.ConclusionThe SGRQ contains some multidimensionality, but an abbreviated version can be used as a unidimensional tool in patients with COPD. Subscale scores should be used with care. SGRQ total scores correlated highly with IRT-based scores, and thus, the weighting methods may be used interchangeably to calculate total scores.

Using multidimensional modeling to combine self-report symptoms with clinical judgment of schizotypy

This study investigated psychometric properties of two widely used instruments to measure subclinical levels of psychosis, the Community Assessment of Psychic Experiences (CAPE) and the Structured Interview for Schizotypy-Revised (SIS-R), and aimed to enhance measurements through the use of multidimensional measurement models. Data were collected in 747 siblings of schizophrenia patients and 341 healthy controls. Multidimensional Item-Response Theory, Mokken Scale and ordinal factor analyses were performed. Both instruments showed good psychometric properties and were measurement invariant across siblings and controls. The latent traits measured by the instruments show a correlation of 0.62 in siblings and 0.47 in controls. Multidimensional modeling resulted in smaller standard errors for SIS-R scores. By exploiting correlations among related traits through multidimensional models, scores from one diagnostic instrument can be estimated more reliably by making use of information from instruments that measure related traits.

Minimizing the testlet effect: Identifying critical testlet features by means of tree-based regression

A broad range of topics is dealt with in this volume: from combining the psychometric generalizability and item response theories to the ideas for an integrated formative use of data-driven decision making, assessment for learning and diagnostic testing. A number of chapters pay attention to computerized (adaptive) and classification testing. Other chapters treat the quality of testing in a general sense, but for topics like maintaining standards or the testing of writing ability, the quality of testing is dealt with more specifically. All authors are connected to RCEC as researchers. They present one of their current research topics and provide some insight into the focus of RCEC. The selection of the topics and the editing intends that the book should be of special interest to educational researchers, psychometricians and practitioners in educational assessment.Standardized tests often group items around a common stimulus. Such groupings of items are called testlets. The potential dependency among items within a testlet is generally ignored in practice, even though a basic assumption of item response theory (IRT) is that individual items are independent of one another. A technique called tree-based regression (TBR) was applied to identify key features of stimuli that could properly predict the dependence structure of testlet data. Knowledge about these features might help to develop item sets with small testlet effects. This study illustrates the merits of TBR in the analysis of test data.