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PubMed2004

Agitated behaviours among the institutionalized elderly with dementia: validation of the Korean version of the Cohen-Mansfield Agitation Inventory.

OBJECTIVES: To analyze the factor structure, the criterion validity, the internal consistency, inter-rater reliability and test-retest reliability of the Korean version of Cohen-Mansfield Agitation Inventory, to provide data on the frequency and distribution of agitated behaviours, and to compare patterns of agitated behaviours among the institutionalized elderly with Alzheimer's disease (AD) or Vascular dementia (VaD). METHODS: The Korean version of the Cohen-Mansfield Agitation Inventory (CMAI-K) was administered to a total of 257 elderly with AD or VaD in a nursing home in Seoul, Korea. Three kinds of reliability and criterion validity were tested. Factor analysis using principal component analysis with the varimax rotation was performed. To identify different patterns of agitated behaviours, multiple logistic regression analysis was used. RESULTS: This study demonstrated satisfactory reliability and validity for the CMAI-K as an instrument measuring agitation in Korean dementia sufferers in nursing homes. Eighty-three percent of the subjects manifested one or more agitated behaviours at least once a week. Factor analysis yielded four subtypes of agitation: physically aggressive behaviours, physically nonaggressive behaviours, verbally agitated behaviours, and hiding/hoarding behaviours. CONCLUSION: These results indicate that the CMAI-K is a reliable and valid instrument to measure agitated behaviours in Korean elderly with AD or VaD. These results validate and expand previous research on the agitation in dementia, and guide in the development of interventions.

Aged↗

PubMed2003

[Development of a self-administered questionnaire to assess women's satisfaction with maternity care].

OBJECTIVES: We describe the development and the validation of a French self-administered questionnaire which measures women satisfaction concerning care given during pregnancy. The analysis includes pregnancy monitoring, hospitalization for delivery and homecoming. METHODS: We considered the content validity, internal-consistency and the reproducibility by test-retest estimates. This survey also compared the characteristics of respondents and non-respondents. RESULTS: Response rate was 61% and the rate of reply per question was greater than 90%. Eleven dimensions are identified by principal-components analysis. Ten of them had good Cronbach's alpha coefficients (0.58 to 0.83). The convergence between open comments and questions and between the different methods to measure satisfaction was good. The test-retest estimates for each dimension were correct. CONCLUSION: This questionnaire is reliable. It is a valid tool for evaluation of satisfaction after pregnancy. Designed to be sent to the woman's residence 2 months after childbirth, it can be easily used in common practice.

Age Factors↗

PubMed2003

The Delirium Observation Screening Scale: a screening instrument for delirium.

The Delirium Observation Screening (DOS) scale, a 25-item scale, was developed to facilitate early recognition of delirium, according to the Diagnostic and Statistical Manual-IV criteria, based on nurses' observations during regular care. The scale was tested for content validity by a group of seven experts in the field of delirium. Internal consistency, predictive validity, and concurrent and construct validity were tested in two prospective studies with high risk groups of patients: geriatric medicine patients and elderly hip fracture patients. Among the patients admitted to a geriatric department (N = 82), 4 became delirious; among the elderly hip fracture patients (N = 92), 18 became delirious. The DOS scale was determined to be content valid and showed high internal consistency, alpha = 0.93 and alpha = 0.96. Predictive validity against the Diagnostic and Statistical Manual-IV diagnosis of delirium made by a geriatrician was good in both studies. Correlations of the DOS scale with the Mini Mental State Examination (MMSE) were Rs -0.79 (p < or = 0.001) in the hip fracture patients and Rs -0.66 (p < or = 0.001) in the geriatric medicine patients. Concurrent validity, as tested by comparison of the research nurse's ratings of the DOS scale and the Confusion Assessment Method (CAM), for the group of hip fracture patients was 0.63 (p < or = 0.001). Construct validity of the DOS was tested against the Informant Questionnaire of Cognitive Decline in Elderly (IQCODE), a preexisting psychiatric diagnosis and the Barthel Index. Correlation with the IQCODE was 0.74 (p < or = 0.001) in the study with the hip fracture patients and 0.33 (p < or = 0.05) in the study with the geriatric medicine patients. Correlation with the Barthel Index was -0.26 (p < or = 0.05) in the geriatric medicine patients and -0.55 (p < or = 0.001) in the hip fracture patients. The overall conclusion of these studies is that the DOS scale shows satisfactory validity and reliability, to guide early recognition of delirium by nurses' observation.

Activities of Daily Living↗

PubMed2002

The psychometric properties of the Interpersonal Sensitivity Measure in social anxiety disorder.

The Interpersonal Sensitivity Measure (IPSM) was developed to assess hypersensitivity to interpersonal rejection, a suggested trait of depression-prone personality (Aust NZ J Psychiatry 23 (1989) 341). Although studies of the IPSM and interpersonal rejection sensitivity have primarily been conducted in depressed populations, it is important to investigate interpersonal rejection sensitivity as a relevant construct in the assessment of social anxiety. This study examined the psychometric properties of the IPSM in treatment-seeking individuals with social anxiety disorder. The results of this investigation support the convergent and divergent validity and internal consistency of the IPSM in socially anxious individuals. An exploratory factor analysis of the scale was also conducted after the original factor and subscale structure was shown to be a poor fit for the present data. Three factors emerged (Interpersonal Worry and Dependency, Low Self-Esteem, and Unassertive Interpersonal Behavior), and 29 items were retained. Because they demonstrated negative factor loadings on Factor 2, it is suggested that the scoring for four items of the original IPSM be reversed. In summary, the revised IPSM assesses three aspects of interpersonal rejection sensitivity and appears to be a valid and reliable instrument for its assessment in social anxiety disorder.

Adult↗

PubMed1996

Measurement properties of a self-administered outcome measure in lumbar spinal stenosis.

STUDY DESIGN: The measurement properties and validity of a newly developed patient questionnaire for the assessment of patients with lumbar spinal stenosis was tested in an ongoing prospective multicenter observational study of patients undergoing decompressive surgery in three teaching hospitals. OBJECTIVE: The goal of the study was to develop a short, self-administered questionnaire on symptom severity, physical functional status, and patient satisfaction. SUMMARY OF BACKGROUND DATA: The measure is intended to complement existing generic measures of spinal-related disability and health status. The questionnaire includes three scales with seven questions on symptom severity, five on physical function, and six on satisfaction. METHODS: The internal consistency of the scales was assessed with Cronbach's coefficient alpha on cross-sectional data from 193 patients before surgery. The test-retest reliability was assessed on data from a random sample of 23 patients using Spearman's rank correlation coefficient. The responsiveness was assessed on 130 patients with 6-month follow-up data using the standardized response mean. RESULTS: The test-retest reliability of the scales ranged from 0.82 to 0.96, the internal consistency from 0.64 to 0.92, and the responsiveness from 0.96 to 1.07. The direction, statistical significance, and strength of hypothesized relationships with external criteria were as expected. CONCLUSIONS: This short self-administered spinal stenosis measure is reproducible, internally consistent, valid, and highly responsive. It can be used to complement generic instruments in outcome assessment of patients with lumbar spinal stenosis.

Aged↗

PubMed2006

Measurement and analysis of angle-resolved scatter from small particles in a cylindrical microchannel.

Scatter of a two-dimensional Gaussian beam of a rectangular cross section by individual particles suspended in a fluid in a cylindrical channel is modeled by using a full-wave approach. First, the internal and scattered fields associated with the cylindrical channel and the two-dimensional Gaussian beam are computed. The spatial variations of the computed electromagnetic field inside the channel indicate that particles and cells of sizes relevant to flow cytometry are subjected to essentially plane-wave illumination, and hence Lorenz-Mie theory is applicable for spherical particles. Further, it is assumed that the perturbation of the electromagnetic field in the channel that is due to the presence of a particle is negligible, allowing us to ignore the interactive scatter of the particle and the channel (they are electromagnetically uncoupled). This approximation is valid when the particle intercepts a small fraction of the total energy inside the channel and when the particle or cell has a low relative refractive index. Measurements of scatter from the channel agree with the analytical model and are used to determine the location of detectors to measure scatter from particles in the channel. Experimental results of accumulated scatter from single latex spheres flowing in the channel show good agreement with computed results, thereby validating the internal field and uncoupled scatter models.

Journal Article↗

PubMed2004

Quality of life after myocardial infarction: translation and validation of the MacNew Questionnaire for a Dutch population.

A wide range of instruments have been used in health-related quality of life (HRQL) assessment of patients with coronary artery disease. The MacNew heart disease health-related quality of life questionnaire (MacNew) is a disease-specific measure of HRQL, that has been found to have both good discriminative and evaluative properties. The objective of the present study was to translate the MacNew for a Dutch population, and assess its reliability and validity. Three hundred and thirty-nine cardiac patients, admitted to the hospital after a cardiac event, participated in the study. Questionnaires were filled out at baseline, at 3 months, and at 12 months. A clinically relevant three-factor solution, reflecting an emotional, physical, and social domain of HRQL, allowed us to explain 55% of variance. Angina pectoris was consistently found to be significantly associated with worse HRQL. The pattern of correlations between the subscales of the MacNew on the one hand, and between the subscales of the MacNew and two other, related questionnaires on the other hand, indicated only modest convergent and discriminant validity. The internal consistency was found to be fair to (very) good (ranging between 0.78 and 0.95). Finally, the Dutch MacNew was demonstrated to be substantially more responsive than two other instruments measuring physical and psychological well-being.

Adult↗

PubMedDate not supplied

AOAC International methods committee guidelines for validation of qualitative and quantitative food microbiological official methods of analysis.

Responding to a need for a guide for conducting Official Method validation studies of microbiological methods, AOAC utilized the experience of three microbiologists who have been active in the field of method validation. In collaboration, a document was prepared which covered the following areas: terms and their definitions associated with the Official Methods program (e.g., reference methods, alternative methods, and ruggedness testing), protocols and validation requirements for qualitative methods versus those for quantitative methods, the concept of the precollaborative study, ruggedness testing, tests for significant differences, performance indicators, and the approval process. After its preparation, this document was reviewed by the members of the Methods Committee on Microbiology and Extraneous Materials and by members of the Official Methods Board. Herein is presented the approved version of that document.

Animal Feed↗

PubMed1999

Reliability and validity of the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) quality of life instrument.

BACKGROUND: This paper describes the development of the Functional Assessment of Cancer Therapy-Colorectal (FACT-C)--a questionnaire assessing quality of life concerns pertinent to colorectal cancer patients. This self-report instrument combines specific concerns related to colorectal cancer with concerns that are common to all cancer patients as assessed with the FACT-General (FACT-G). METHOD: Three separate and distinct validation samples were used with different ethnic and stage of disease compositions. RESULTS: Results suggest that the FACT-C is a reliable and valid measure in both its English and Spanish language versions. Specifically, the FACT-C evidenced good internal consistency reliability and concurrent validity, as well as an ability to distinguish between groups based on functional status and extent of disease. The FACT-C was also found to be sensitive to changes in functional status. Colorectal cancer-specific items form the Colorectal Cancer Subscale (CCS) which was found to have adequate convergent and divergent validity. Internal consistency was adequate in most samples. In addition, the CCS was able to distinguish among groups that differed in functional status and was sensitive to change in functional status. CONCLUSION: It is recommended that the entire FACT-C (rather than simply the CCS) be used when studying patients with colorectal cancer in order to provide a comprehensive assessment of quality of life. Recommendations are offered concerning the appropriate use of these measures in clinical research and directions for future research with colorectal cancer patients.

Activities of Daily Living↗

PubMed2002

Quality of life in patients with traumatic brain injury-basic issues, assessment and recommendations.

INTRODUCTION: Traumatic brain injuries (TBI) are one of the most common consequences of traffic accidents. Patients with mild, moderate or severe brain injuries suffer from physical, cognitive, behavioral, emotional and social problems. Most of these problems have been a long standing focus amongst practitioners and researchers. Only recently a development has started that took interest in the quality of life outcome of TBI patients. The international members of this consensus meeting reviewed the literature on Quality of Life assessment after TBI and discussed the applicability of different measurements to this specific patient group. TIME POINTS: During the acute phase (T1; < 3 month after trauma) QoL it is difficult to assess due to the reduced consciousness of TBI patients. In the phase of rehabilitation (T2; < one year after trauma) and in the post-rehabilitation phase (T3) repeated assessment of QoL is recommended. INSTRUMENTS: Several generic and disease-specific instruments possibly relevant to TBI patients or specifically developed for this group were assessed according to the existing evidence in the literature. Criteria for the evaluation of these instruments were: feasibility, specificity, validity, comprehensiveness, international availability, existence of norms, and psychometric quality. The cognitive impairment and the existential dimension were not sufficiently considered in most of the reviewed instruments. GROUP CONSENSUS: The family's and relatives' view of the patient's QoL should not be used as a proxy but provides an additional source of information in the acute phase. At T2 and T3, assessment of the patient's quality of life should include a generic as well as a disease specific instrument. Among the generic instruments the SF-36, the EuroQol and the WHO-QoL should be considered. The literature about specific instruments for patients with TBI like the EBIC is scarce. Therefore, the group could hardly give an empirically based recommendation. The need for further investigation on QoL instruments in TBI patients is strongly emphasized.

Brain Injuries↗

PubMed1999

Validation of a French version of the Dissociative Experiences Scale in a rape-victim population.

OBJECTIVE: To appreciate the extent and the features of dissociation in a hypothesized highly dissociated population, rape trauma victims, while assessing construct validity and internal consistency of a French version of the Dissociative Experiences Scale (DES), a simple screening instrument for dissociative symptoms. METHODS: One hundred and forty rape victims (mean age 23.6 years, 9% male) consecutively attending a Consultation for Victims of Psychological Trauma at the university hospital in Tours, France, were assessed through a French version of the 28-item self-rated DES. RESULTS: The mean score (24.1) was high, and 33% of the scores exceeded a threshold set at 30. The Principal Components Analysis of the DES ratings yielded a 3-factor solution: depersonalization-derealization, amnestic fragmentation of identity, and absorption-imaginative involvement. DES reliability was studied through computation of Cronbach's alpha coefficient (0.94). CONCLUSION: During validation of a French version of the DES, the study showed that dissociation is considerably linked to rape-trauma victim populations.

Adolescent↗

PubMed2005

Using item response theory to explore the psychometric properties of extended matching questions examination in undergraduate medical education.

BACKGROUND: As assessment has been shown to direct learning, it is critical that the examinations developed to test clinical competence in medical undergraduates are valid and reliable. The use of extended matching questions (EMQ) has been advocated to overcome some of the criticisms of using multiple-choice questions to test factual and applied knowledge. METHODS: We analysed the results from the Extended Matching Questions Examination taken by 4th year undergraduate medical students in the academic year 2001 to 2002. Rasch analysis was used to examine whether the set of questions used in the examination mapped on to a unidimensional scale, the degree of difficulty of questions within and between the various medical and surgical specialties and the pattern of responses within individual questions to assess the impact of the distractor options. RESULTS: Analysis of a subset of items and of the full examination demonstrated internal construct validity and the absence of bias on the majority of questions. Three main patterns of response selection were identified. CONCLUSION: Modern psychometric methods based upon the work of Rasch provide a useful approach to the calibration and analysis of EMQ undergraduate medical assessments. The approach allows for a formal test of the unidimensionality of the questions and thus the validity of the summed score. Given the metric calibration which follows fit to the model, it also allows for the establishment of items banks to facilitate continuity and equity in exam standards.

Adult↗

PubMed2006

Redesign and initial validation of an instrument to assess the motivational qualities of music in exercise: the Brunel Music Rating Inventory-2.

In the present study, a measure to assess the motivational qualities of music in exercise was redesigned, extending previous research efforts (Karageorghis et al., 1999). The original measure, the Brunel Music Rating Inventory (BMRI), had shown limitations in its factor structure and its applicability to non-experts in music selection. Redesign of the BMRI used in-depth interviews with eight participants (mean age 31.9 years, s = 8.9 years) to establish the initial item pool, which was examined using a series of confirmatory factor analyses. A single-factor model provided a good fit across three musical selections with different motivational qualities (comparative fit index, CFI: 0.95-0.98; standardized root mean residual, SRMR: 0.03-0.05). The single-factor model also demonstrated acceptable fit across two independent samples and both sexes using one piece of music (CFI: 0.86-1.00; SRMR: 0.04-0.07). The BMRI was designed for experts in selecting music for exercise (e.g. dance aerobic instructors), whereas the BMRI-2 can be used both by exercise instructors and participants. The psychometric properties of the BMRI-2 are stronger than those of the BMRI and it is easier to use. The BMRI-2 provides a valid and internally consistent tool by which music can be selected to accompany a bout of exercise or a training session. Furthermore, the BMRI-2 enables researchers to standardize music in experimental protocols involving exercise-related tasks.

Adult↗

PubMed1999

Development of a Chinese chronic illness-related stress inventory for primary care.

This study evaluates the construct validity and internal consistency of a Chronic Illness-Related Stress Inventory (CRSI) for primary care Chinese patients and studies the relationship between chronic illness-related stress and sociodemographic characteristics and indices of disease severity. A total of 301 patients were interviewed using a structured questionnaire. The responses to the CRSI were divided into a frequency scale and a severity scale. Six factors including physical integrity and discomfort, psychosocial function and economic burdens, self-fulfillment and daily life, sexual function, self-esteem, and diet limitations were obtained for each CRSI scale. Except for the last factor, all other factors and the scale as a whole for both scales have a Cronbach alpha of > 0.90. The results of the convergent and discriminant validity analysis were promising. In addition, chronic illness-related stress was related to insurance status and the self-perceived severity of disease.

Adult↗

PubMed2006

Development and initial validation of the Stress of Conscience Questionnaire.

Stress in health care is affected by moral factors. When people are prevented from doing 'good' they may feel that they have not done what they ought to or that they have erred, thus giving rise to a troubled conscience. Empirical studies show that health care personnel sometimes refer to conscience when talking about being in ethically difficult everyday care situations. This study aimed to construct and validate the Stress of Conscience Questionnaire (SCQ), a nine-item instrument for assessing stressful situations and the degree to which they trouble the conscience. The items were based on situations previously documented as causing negative stress for health care workers. Content and face validity were established by expert panels and pilot studies that selected relevant items and modified or excluded ambiguous ones. A convenience sample of 444 health care personnel indicated that the SCQ had acceptable validity and internal consistency (Cronbach's alpha exceeded 0.83 for the overall scale). Explorative factor analysis identified and labelled two factors: 'internal demands' and 'external demands and restrictions'. The findings suggest that the SCQ is a concise and practical instrument for use in various health care contexts.

Adult↗

PubMed2003

Construct validity of the abbreviated mental test in older medical inpatients.

OBJECTIVES: To evaluate validity and internal structure of the Abbreviated Mental Test (AMT), and to assess the dependence of the internal structure upon the characteristics of the patients examined. DESIGN: Cross-sectional examination using data from the Italian Group of Pharmacoepidemiology in the Elderly (GIFA) database. SETTING: Twenty-four acute care wards of Geriatrics or General Medicine. PARTICIPANTS: Two thousand eight hundred and eight patients consecutively admitted over a 4-month period. MEASUREMENTS: Demographic characteristics, functional status, medical conditions and performance on AMT were collected at discharge. Sensitivity, specificity and predictive values of the AMT <7 versus a diagnosis of dementia made according to DSM-III-R criteria were computed. The internal structure of AMT was assessed by principal component analysis. The analysis was performed on the whole population and stratified for age (<65, 65-80 and >80 years), gender, education (<6 or >5 years) and presence of congestive heart failure (CHF). RESULTS: AMT achieved high sensitivity (81%), specificity (84%) and negative predictive value (99%), but a low positive predictive value of 25%. The principal component analysis isolated two components: the former component represents the orientation to time and space and explains 45% of AMT variance; the latter is linked to memory and attention and explains 13% of variance. Comparable results were obtained after stratification by age, gender or education. In patients with CHF, only 48.3% of the cumulative variance was explained; the factor accounting for most (34.6%) of the variance explained was mainly related to the three items assessing memory. CONCLUSION: AMT >6 rules out dementia very reliably, whereas AMT <7 requires a second level cognitive assessment to confirm dementia. AMT is bidimensional and maintains the same internal structure across classes defined by selected social and demographic characteristics, but not in CHF patients. It is likely that its internal structure depends on the type of patients. The use of a sum-score could conceal some part of the information provided by the AMT.

Aged↗

PubMed2005

Development of a solid-phase extraction-HPLC/single quadrupole MS method for quantification of perfluorochemicals in whole blood.

A method for the determination of perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) simultaneously with 10 closely related perfluorochemicals (PFCs) in human whole blood was developed and validated. PFOS and PFOA are used in various applications, for example, as surfactants and plastic additives, and are subject to environmental and health research due to their persistence. The main part of the data on PFCs in human blood is from serum samples, analyzed mainly by ion pair extraction followed by high-performance liquid chromatography (HPLC) and negative electrospray (ESI) tandem mass spectrometry (MS/MS). The analytical method developed here is suitable for human whole blood and involves solid-phase extraction (SPE) and HPLC negative electrospray single quadrupole mass spectrometry (HPLC/ES-MS). A whole blood aliquot was treated with formic acid and extracted on a octadecyl (C18) SPE column. The PFCs were isolated with methanol, and quantification was performed using single quadrupole mass spectrometry and perfluoroheptanoic acid as internal standard. Validation was performed in the range 0.3-194 ng/mL with recovery between 64 and 112% and limit of detection in the 0.1-0.5 ng/mL range for 11 of the 12 PFCs studied. We applied this method to 20 whole blood samples collected in 1997-2000 from the Swedish population in the ages 24-72. Eleven of the 12 PFCs were detected, and they were quantitatively and qualitatively confirmed using triple quadrupole LC/MS/MS analysis. PFOS, perfluorooctanesulfonamide, perfluorohexanesulfonate, PFOA and perfluorononanoic acid were quantified in all samples. In addition, perfluorohexanoic acid, perfluorodecanoic acid, perfluorodecanesulfonate, perfluoroundecanoic acid, perfluorododecanoic acid, and perfluorotetradecanoic acid were detected in some samples. This study shows that SPE and single quadrupole MS can be applied for extraction and quantification of PFCs in human whole blood, resulting in selectivity and low detection limits.

Alkanesulfonic Acids↗

PubMed1991

The internal reference technique in microdialysis: a practical approach to monitoring dialysis efficiency and to calculating tissue concentration from dialysate samples.

In microdialysis experiments, 'recovery' estimations are required to calculate extracellular concentrations of the compounds determined. Generally, relative recovery (RR) is determined in vitro as: RR = cd/cs, with (cd) being the concentration of a compound in a dialysate fraction and (cs) its known concentration within a sample solution. To determine recoveryin vivo, relative loss (RL) was defined RL = (cp-cd)/cp with (cp-cd) being the loss of a compound from the perfusate and (cp) its perfusate concentration. RL was determined in vitro and in vivo by adding an 'internal reference compound' to the perfusate. Here, 14C-labelled lactate was used as the compound of interest. Comparing RL and RR in vitro, we found both to be similar. In vivo, however, RL was 34% of RL(in) vitro (CSF) and 46% of RL(in) vitro in agar-containing CSF. During ischaemia, RL of lactate even decreased to only 35% of the pre-ischaemic control level. We conclude that RL and RR represent inverse measurements of 'recovery.' Whereas RR can only be determined in vitro, RL can be determined in vivo. We found recoveryin vivo to be different from recoveryin vitro. Moreover, recoveryin vivo decreased during ischaemia. By means of the measured recoveryin vivo extracellular lactate concentrations prior and during ischaemia were calculated. The results, therefore, validate the 'internal reference technique' as a practical method for estimating recoveryin vivo and for controlling dialysis efficacy in vivo even continuously.

Animals↗