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Factor structure and differential validity of the expanded Brief Psychiatric Rating Scale.

The Brief Psychiatric Rating Scale (BPRS) is one of the most widely used measures in psychiatric outcome and clinical psychopharmacology research. To date, however; research on the psychometric properties of the expanded version of the BPRS (BPRS-E) has been limited. An exploratory factor analysis (n = 360) using maximum likelihood extraction with oblimin rotation found a four-factor solution (Thought Disturbance, Animation, Mood Disturbance, Apathy) to underlie the BPRS-E. Furthermore, these factors were logical in nature and estimates of internal consistency were acceptable. A confirmatory factor analysis conducted on a second, independent sample (n = 280)found that for the five models currently available in the literature, the model developed herein provided the best fit to the data. Again, estimates of internal consistency were found acceptable. Finally, the four factors demonstrated appropriate differential validity with regards to both demographic variables and various psychiatric diagnoses.

Adolescent↗

Structure, use, and validation of the IEUBK model.

The potential impact of the effects of lead in children is a major concern. Although measurements of lead concentration can be made in a geographic area, it is difficult to predict the effects of this exposure that involve complicated biologic functions. Dynamic mathematical models that can be simulated on a digital computer provide one method of analysis to facilitate the prediction process. The integrated exposure uptake biokinetic (IEUBK) model is a dynamic mathematical model that has been discretized for execution on a digital computer. This paper is concerned with the general difficulties in validating a dynamic model of this type. A number of the general pitfalls of validating a model of this type are presented. The illustrations are of a general nature not requiring an understanding of the physiologic effects of lead on children. The concept of validating a model by comparing results to historical data is discussed. A comparison is made with traditional modeling efforts having this form of dynamic model. Also included are general mathematic concepts illustrating potential difficulties with intuitive analyses in calibrating a dynamic model.

Animals↗

Heterogeneous nucleation in sickle hemoglobin: experimental validation of a structural mechanism.

Sickle hemoglobin polymerizes by two types of nucleation: homogeneous nucleation of aggregates in solution, and heterogeneous nucleation on preexisting polymers. It has been proposed that the same contact that is made in the interior of the polymer between the mutant site beta6 and its receptor pocket on an adjacent molecule is the primary contact site for the heterogeneous nucleus. We have constructed cross-linked hybrid molecules in which one beta-subunit is from HbA with Glu at beta6, and the other is from HbS with a Val at beta6. We measured solubility (using sedimentation) and polymerization kinetics (using laser photolysis) on cross-linked hybrids, and cross-linked HbS as controls. We find approximately 4000 times less heterogeneous nucleation in the cross-linked AS molecules than in cross-linked HbS, in strong confirmation of the proposal. In addition, changes in stability of the nucleus support a further proposal that more than one beta6 contact is involved in the homogeneous nucleus.

Binding Sites↗

Factor structure and construct validity of the Denman Neuropsychology Memory Scale.

Correlational data on the recently published Denman Neuropsychology Memory Scale (DNMS; Denman, 1984) were subjected to a series of factor analyses. Although a major feature of the DNMS is computation of Verbal, Non-Verbal and Full Scale Memory Quotients, the factor analyses did no support this practice. Since the factor results demonstrated initial support for the construct validity of some of the DNMS subtests, it is recommended that interpretation be based on subtest performance. The present results and suggested future investigations of DNMS construct validity are discussed in relation to current issues in clinical memory assessment.

Adolescent↗

Reliability and validity of a structured interview guide for the Hamilton Anxiety Rating Scale (SIGH-A).

The Hamilton Anxiety Rating Scale, a widely used clinical interview assessment tool, lacks instructions for administration and clear anchor points for the assignment of severity ratings. We developed a Structured Interview Guide for the Hamilton Anxiety Scale (SIGH-A) and report on a study comparing this version to the traditional form of this scale. Experienced interviewers from three Anxiety Disorders research sites conducted videotaped interviews using both traditional and structured instruments in 89 participants. A subset of the tapes was co-rated by all raters. Participants completed self-report symptom questionnaires. We observed high inter-rater and test-retest reliability using both formats. The structured format produced similar but consistently higher (+ 4.2) scores. Correlation with a self-report measure of overall anxiety was also high and virtually identical for the two versions. We conclude that in settings where extensive training is not practical, the structured scale is an acceptable alternative to the traditional Hamilton Anxiety instrument.

Anxiety Disorders↗

Development and psychometric evaluation of supportive leadership scales.

The purpose of this study was to develop and evaluate the psychometric properties of 2 supportive leadership scales, the Charge Nurse Support Scale and the Unit Manager Support Scale, designed for long-term-care environments. These 6-item self-report scales were administered to 70 nursing staff and their internal consistency reliability, test-retest reliability, content validity, factor structure, and construct validity investigated. Content validity was established with the assistance of experts. Both scales were deemed reliable. As hypothesized, a significant relationship was found between the measure of how nursing staff related to residents and measures of charge nurses' supportive behaviours (r = .42, p = .05). Reliable and valid measures of supportive leadership could be developed for use in identifying the quality of support provided to staff in long-term-care environments.

Adult↗

Two-dimensional real-time ultrasonic imaging of the heart and great vessels. Technique, image orientation, structure identification, and validation.

Conventional M-mode echocardiography has become established as a diagnostic tool for noninvasive evaluation of cardiovascular diseases. Now the advent of two-dimensional real-time echocardiography has opened a new era of investigation. This paper describes in detail the technique of a complete two-dimensional ultrasonic examination of the heart and great vessels. Four transducer locations were commonly utilized--namely, parasternal, apical, subxiphoid, and suprasternal notch positions. The tomographic sections of the heart obtained along the long and short axes of the heart and great vessels by utilizing the above positions were validated by detailed anatomic and contrast echocardiographic techniques.

Echocardiography↗

Diagnosing depression in the medically ill: validity of a lay-administered structured diagnostic interview.

Understanding the validity of structured psychiatric diagnostic interviews in medically ill patients will advance the ability to conduct research into the treatment and management of these disorders in general medical settings. We compared the University of Michigan version of the CIDI (Composite International Diagnostic Interview) for major depression to a clinical gold standard, derived through Spitzer's Longitudinal, Expert, All Data (LEAD) criteria based on the SCID-III-R. A convenience sample of medical inpatients was administered the SCID-III-R and the CIDI for major depression in random order. A physician panel reviewed the SCID interview and other pertinent data and determined whether patients had a lifetime or current (past month) diagnosis of major depression. The CIDI was scored with and without hierarchical exclusions for mania, hypomania, substance use, or medical illness. When the UM-CIDI was scored for a lifetime diagnosis of major depression without hierarchical exclusions, agreement above chance (kappa) was very good (kappa = 0.67) between the CIDI and the physician panel and good (kappa = 0.46) when the UM-CIDI was scored with exclusions. Agreement above chance for diagnosis of a recent disorder was better for UM-CIDI scoring with exclusions (kappa = 0.51) compared to scoring without exclusions (kappa = 0.43). Predictive value-positive was excellent in both scoring versions for a lifetime diagnosis (82%) and good to very good for current depression (46% and 62%). In all cases predictive value-negative was very good to excellent (77-93%). Discordant cases were almost uniformly due to difficulties in attribution of symptoms to medical illnesses. We conclude that the CIDI can perform acceptably as a research instrument to diagnose major depression in medically ill patients, potentially supplemented by clinician review of cases identified by the CIDI with current disorder.

Adult↗

EUROQUEST--a questionnaire for solvent related symptoms: factor structure, item analysis and predictive validity.

The study evaluates the factor structure and predictive validity of the symptom questionnaire EUROQUEST (EQ) that had been developed with the goal of simplifying the evaluation of health effects associated with long-term solvent exposure. The EQ was added to the normal evaluation procedures for 118 male patients with suspected solvent-induced toxic encephalopathy (TE) referred to seven Swedish clinics of occupational medicine during an 18-month period. EQ was also completed by 239 males from a random sample of 400 Swedish males aged 25-64 years selected from the general population and a sample of 559 occupationally active male spray painters aged 25-64 years. Factor and item analyses of EQ responses were performed. Ordinary least square regression analysis was used to evaluate sensitivity and correlation to evaluate the specificity of EQ and the separate components. Questions concerning memory and concentration symptoms alone showed better sensitivity than the other five EQ dimensions singly or combined for the entire EQ and for a subset of questions approximating Q16, a widely used organic solvent symptom screening questionnaire. However, the diagnosis of TE required information in addition to exposure and responses to EQ and Q16-like questions. The results indicate that the subset of EQ questions concerning memory and concentration might replace the more cumbersome EQ and less sensitive Q16 in screening for TE, although none of the screening instruments alone replaces current clinical diagnostic procedures.

Adult↗

[On the validity of the axis "Structure" of operationalized psychodynamic diagnostics].

OBJECTIVES: As part of the concurrent validity, we aimed to empirically study the association between the axis IV (structure) of the Operationalized Psychodynamic Diagnostics (OPD) and corresponding constructs, which were assessed byself-report measures. METHODS: The structural level of 132 psychiatric inpatients was related to the findings of the Borderline-Personality-Inventary (BPI) and the Toronto-Alexithymia-Scale (TAS-20). RESULTS: Analyses of variances indicated that patients with a good structural level scored lower on the BPI and its subscales than those with a low level. However, posthoc comparisons revealed that significant differences were only found between the good and the moderate or the low level respectively. There was no association between the structure and alexithymia. CONCLUSIONS: Despite some methodological limitations our findings point at a satisfactory validity of the axis "structure" of the OPD. However, its limited ability to discriminate between patients with a moderate and a low level of structural integration needs further attention.

Adult↗

Validation of an objective structured clinical examination in psychiatry.

PURPOSE: To examine the validity of a psychiatry clerkship's objective structured clinical examination (OSCE). METHOD: In 1996, 33 clinical clerks and 17 psychiatry residents at the University of Toronto participated in an eight-station OSCE evaluated by psychiatrist-examiners using binary checklists and global ratings. Prior to the OSCE, communication course instructors were asked to rank the clerks on interviewing ability, and faculty supervisors were asked to identify the OSCE stations on which the clerks were likely to do well or poorly. RESULTS: Mean OSCE scores were significantly higher for the residents than for the clerks on global ratings but not on checklists. The communication instructors accurately predicted the clerks' rankings on the global scores but not their scores on the checklists. The faculty supervisors predicted with moderate accuracy the clerks' success on the OSCE stations as measured by the checklists but not by the global ratings. The residents rated the OSCE scenarios as highly realistic. CONCLUSIONS: The evidence of construct and concurrent validity together with high ratings of realism suggest that a psychiatry OSCE can be a valid assessment of clerks' clinical competence.

Clinical Clerkship↗

Validation of single-factor structure and scoring protocol for the Health Assessment Questionnaire-Disability Index.

OBJECTIVE: The extensively used Health Assessment Questionnaire Disability Index (HAQ-DI) has been well received by the research and clinical community, notably because of its measurement strengths including reliability and stability of scores over time, utility in observational studies and clinical trials, predictive relationship with morbidity and mortality in rheumatoid arthritis (RA), and its translation for use in different countries. However, HAQ-DI scoring has not been validated. The purpose of this study was to examine the structural validity of the HAQ-DI and evaluate the latent factors underlying HAQ-DI scoring. METHODS: This study used a cross-validation approach on a total of 278 patients with RA. Exploratory and confirmatory factor analyses were performed. RESULTS: Results yielded a single-factor HAQ-DI score, which favored the current scoring system of the HAQ-DI. Additionally, modification indices suggested improved model fit with the secondary inclusion of correlated residual scores from a motor skills subdomain. CONCLUSION: The current study provides the first validation of the HAQ-DI scoring system as determined by its latent factor structure. In addition, the findings suggest some benefit from a secondary interpretation of the scores based on domains that measure motor skills.

Arthritis, Rheumatoid↗

Cross-validation of the factor structure of the Toronto Alexithymia Scale.

The Toronto Alexithymia Scale (TAS) is a self-report measure of the alexithymia construct. In previous studies with college students, the TAS demonstrated excellent psychometric properties including a 4-factor structure theoretically congruent with the alexithymia construct. The present study attempted to cross-validate the factor structure of the TAS with samples of normal adults, psychiatric outpatients and college students. Congruence coefficients comparing the similarity of the factor structures for these three samples indicated good congruence for all four factors. The results provide further support for the validity of both the TAS and the alexithymia construct. In addition, the results provide evidence of the applicability of the scale to normal adult and clinical samples.

Adult↗

Cancer-specific social support received by newly diagnosed cancer patients: validating the new Structural-Functional Social Support Scale (SFSS) measurement tool.

GOALS OF WORK: To investigate potentially health-enhancing domains of cancer patients' social relationships we evaluated various dimensions of social support as experienced in early cancer. PATIENTS AND METHODS: In consecutive samples of 72 melanoma and 103 breast cancer patients diagnosed 3-4 months earlier, we evaluated the cancer-specific social network and received social support by the Structural-Functional Social Support Scale (SFSS) validated within the study. In addition, social support was measured by the MOS Social Support Survey as perceived support, and by Seeking Social Support items from the Ways of Coping Questionnaire as coping activity. SFSS measures the number of people who have been aware of the patient's cancer and the amount of social support the patients have received from them. MAIN RESULTS: A large number of people from various potential support-providing sources had been aware of the patients' cancer, and the patients had received support through these interactions. A greater number of support providers did not mean an increase in the support received. Social support was distinguished into subgroups according to its source, but the division into functional support types was weak. Support assessed as perceived support or as a coping activity did not cover the received disease-specific support of several sources. CONCLUSIONS: With the SFSS, it was possible to obtain detailed information on the disease-specific social network and social support. It may be beneficial to distinguish support according to the sources and to also measure support beyond the closest relationships. We hope that our measure and the results obtained will assist in identifying the targets for psychosocial interventions.

Adult↗

Validation of an objective structured assessment of technical skill for surgical residents.

PURPOSE: This study examined the concurrent validity of the Objective Structured Assessment of Technical Skill (OSATS), a new test of technical skill for general surgery residents. METHOD: Twelve residents (six in their senior, or fifth, year and six in their junior, or third, year) at the University of Toronto in 1994-95 were ranked within level of training according to their OSATS marks and by surgical faculty. Correspondence between OSATS and faculty rankings was assessed using Spearman rank-order correlation coefficients. RESULTS: The correlations between test scores and faculty rankings were generally high for the senior residents but low for the junior residents. CONCLUSION: Scores on the OSATS accurately reflect the independent opinions of faculty regarding the technical skills of senior residents, suggesting that it is a valid measure of technical skill for these individuals. The scores did not, however, reproduce faculty rankings of the junior residents. Whether this was a failing of the OSATS or the faculty rankings requires further study.

Clinical Competence↗