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PubMed2001

Development of instruments to measure appraisal of care among Japanese family caregivers of the elderly.

The purpose of this study was to develop two instruments for the evaluation of positive and negative appraisal of care among family caregivers of elderly Japanese care recipients within the framework of caregiver adaptation. The positive appraisal of care instrument (PAC) includes domains of relationship satisfaction, role confidence, consequential gain, and normative fulfillment. The negative appraisal of care instrument (NAC) includes domains of role exhaustion, isolation, relationship difficulty, and symptom management difficulty. The PAC and NAC are self-administered questionnaires and were developed from data collected from 337 family caregivers of relatives aged 65 years and over who were using visiting nursing services from 21 organizations in multiple areas of Japan. Out of 87 items, 21 PAC items and 14 NAC items were selected based on content and construct validity and internal consistency examination. Results show evidence of validity and reliability for the PAC and NAC, although some NAC domains may benefit from further refinement. The PAC and NAC will be useful research tools for examining elder caregiving experience and evaluating nursing care for elders.

Activities of Daily Living↗

PubMed2006

The Cumberland ankle instability tool: a report of validity and reliability testing.

OBJECTIVE: To test the Cumberland Ankle Instability Tool (CAIT), a 9-item 30-point scale, for measuring severity of functional ankle instability. DESIGN: Cross-sectional study. SETTING: General community. PARTICIPANTS: Volunteer sample of 236 subjects. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Concurrent validity by comparison with the Lower Extremity Functional Scale (LEFS) and a visual analog scale (VAS) of global perception of ankle instability by using the Spearman rho. Construct validity and internal reliability with Rasch analysis using goodness-of-fit statistics for items and subjects, separation of subjects, correlation of items to the total scale, and a Cronbach alpha equivalent. Discrimination score for functional ankle instability by maximizing the Youden index and tested for sensitivity and specificity. Test-retest reliability by intraclass correlation coefficient, model 2,1 (ICC(2,1)). RESULTS: There were significant correlations between the CAIT and LEFS (rho=.50, P<.01) and VAS (rho=.76, P<.01). Construct validity and internal reliability were acceptable (alpha=.83; point measure correlation for all items, >0.5; item reliability index, .99). The threshold CAIT score was 27.5 (Youden index, 68.1); sensitivity was 82.9% and specificity was 74.7%. Test-retest reliability was excellent (ICC(2,1)=.96). CONCLUSIONS: CAIT is a simple, valid, and reliable tool to measure severity of functional ankle instability.

Adult↗

PubMed2000

Development of the vestibular disorders activities of daily living scale.

BACKGROUND: Existing scales of self-perceived disablement in patients with vestibular impairment either are too broad to detect the subtle deficits in this population or omit some important daily life tasks. OBJECTIVES: To develop a scale to assess self-perceived disablement in patients with vestibular impairment and to describe the development and initial testing of this new assessment tool. DESIGN: A list of items was developed, sent to a panel of expert therapists for review, and then revised to yield the preliminary 31-item, 10-point scale that was administered to subjects. The scale was revised again, yielding the final 28-item scale, which was administered to a new group of subjects. SETTING: Data were collected from patients in an outpatient clinic of a tertiary care center. PARTICIPANTS: Patients diagnosed as having benign paroxysmal positional vertigo and patients diagnosed as having chronic vestibulopathy, excluding Ménière disease, postsurgical vertigo, and postconcussion vertigo. RESULTS: The final scale has 3 subscales: functional, ambulation, and instrumental. It has good face validity, high internal consistency (alpha> or =.90), and high test-retest reliability (r(c)> or =0.87). Scale ratings ranged from 1 (independent) to 10 (ceasing to participate in the activity), but median scores for most subjects were 4 or less. From 41% (39/94) to 44% (41/94) of subjects considered themselves to be independent on those tasks. CONCLUSIONS: This scale has good face validity, high internal consistency, and high test-retest reliability. It may be useful for evaluating functional limitation and perceived handicap or disability before and after intervention and for helping patients become more realistic in understanding their own capabilities.

Activities of Daily Living↗

PubMed2001

General scales of community reaction to noise (dissatisfaction and perceived affectedness) are more reliable than scales of annoyance.

General measures of reaction to noise, which assess the respondent's perceived affectedness or dissatisfaction, appear to be more valid and internally consistent than more narrow measures, such as specific assessment of noise annoyance. However, the test-retest reliability of general and specific measures has yet to be compared. As a part of the large-scale Sydney Airport Health Study, 97 respondents participated in the same interview twice, several weeks apart. Test-retest reliabilities were found to be significant (p < 0.001) for two general questions and three specific "annoyance" questions. The general measures were significantly more valid for four of the six correlations (with activity disturbance), and more stable than the annoyance scales for five of the six possible test-retest comparisons. Amongst 1,015 respondents at Time 1, the questions regarding general reaction were more internally consistent than the questions regarding annoyance. Taken together, these data indicate that general measures of reaction to noise have superior psychometric properties (validity, internal consistency, and stability) compared with measures of specific reactions such as annoyance.

Adolescent↗

PubMedDate not supplied

Pain experienced by patients hospitalized at the National Cancer Institute of Milan: research project "towards a pain-free hospital".

According to the data of the literature, the prevalence of pain in cancer patients at various stages of the disease and the settings of care range from 38 to 51%, with an increase of up to 74% in the advanced and terminal stages. Despite published World Health Organization (WHO) guidelines for pain management, 42 to 51% of cancer patients receive inadequate analgesia and 30% receive no analgesics at all. A 3-year Research Project "Towards a Pain-free Hospital", which began one year ago, is ongoing at the National Cancer Institute of Milan. The research is organized in three subsequent steps. In the 1st one, a series of patient- and staff-oriented evaluation tools are used to assess the level of appropriateness of pain communication, assessment, management and control of the in-patients. The 2nd step will implement a number of continuing educational interventions aimed at improving patient awareness and staff knowledge of the appropriate pain assessment and management in order to respond to the patient's pain problem. In the 3rd step, all the assessment tools used in step one will be applied again to establish the prevalence of pain, the causes and intensity and patient satisfaction with pain management and to evaluate the impact of the interventions performed during the 2nd step regarding the overall ability of our hospital to tackle pain emergency in the hospitalized cancer population. The results relative to the 1st step are herein reported, in particular as regards the study on prevalence, causes, severity of pain, the interference of pain with sleep, mood and concentration, the use of pain medications and the relief obtained, the structural validity and internal consistency of the assessment tool used. A total of 258 patients hospitalized for at least 24 h were interviewed by 9 physicians using a brief structured questionnaire prepared ad hoc: 51.5% of the patients presented pain during the previous 24 h caused by surgery (49.6%) or by the tumor mass itself (29.3%). Out of the 133 patients with pain, a high degree (much or very much) of pain at rest was present in 27.1% and pain on movement in 30.8%; 31.6% did not take any analgesic treatment, and 14.3% of the latter reported a high degree of pain at rest and 21.4% on movement. Pain interfered with sleep from much to very much in 28.8% and with irritability and nervousness in 15.9% of the patients. In the 91 patients taking analgesics, 57.2% reported a high degree of pain relief. A high degree of pain and interference, however, was associated with low relief levels. The assessment tool used was shown to have a good structural validity and internal consistency (Chrombach alpha index of interference scale = 0.73). Although the Milan Cancer Institute has the longest tradition in Italy of pain assessment by means of validated tools and pain management according to the WHO guidelines and educational efforts in this field, the results of the study clearly show that it is necessary to persevere with continuing educational and informative programs in order to reduce the frequency and severity of pain and thus improve the quality of life of in-patients.

Adult↗

PubMed2004

Issues in cross-cultural validity: example from the adaptation, reliability, and validity testing of a Turkish version of the Stanford Health Assessment Questionnaire.

OBJECTIVE: Guidelines have been established for cross-cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ). METHODS: Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross-cultural validity is tested through DIF by comparison with data from the UK version of the HAQ. RESULTS: The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (alpha = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item. CONCLUSIONS: Cross-cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.

Activities of Daily Living↗

PubMed2001

Grading of internal carotid artery stenosis: validation of Doppler/duplex ultrasound criteria and angiography against endarterectomy specimen.

OBJECTIVES: duplex ultrasound has replaced angiography prior to carotid endarterectomy (CEA) in many institutions. However, the indications for CEA are based on angiographically controlled studies and widely accepted ultrasound criteria do not exist. Consequently, the reliability of Doppler and/or duplex ultrasound to predict a high-grade ICA stenosis has to be proven. DESIGN: prospective validation study. MATERIALS: one hundred and fifty carotid bifurcations assessed by ultrasound and selective angiography and 68 acrylat outcasts of carotid specimen after eversion CEA. METHODS: ICA stenosis was measured angiographically according to the ECST criteria. Combined Doppler acoustic standard criteria (CDASC), peak systolic frequency (PSF), peak systolic velocity (PSV) and end-diastolic velocity (EDV) served as criteria for the ultrasound assessment. These criteria and the results of angiography were compared to the degree of ICA stenosis determined by specimen measurements. RESULTS: the median degree of ICA stenosis as assessed by angiography (82%, range 56-97%) and CDASC (83%, range 50-99%) corresponded well to the specimen measurements (80%, range 50-95%). The sensitivity of angiography and CDASC to predict a 70-90% ICA stenosis (ECST criteria) compared to the specimen measurements was 88% and 95%, respectively. The positive predictive value (PPV) reached 92% and 96%, respectively. CDASC were equivalent to angiography and were superior to the best single frequency or velocity parameters. If CDASC do not indicate a >/=70% ICA stenosis in spite of a PSV >/=180 cm/s and/or an EDV >/=50 cm/s, angiography may detect patients with a >70% ICA stenosis. CONCLUSIONS: CDASC are valid in the quantification of high-grade ICA stenosis. They are more reliable than single velocity and/or frequency measurements. However, if velocity criteria and CDASC do not agree, angiography should be performed.

Angiography↗

PubMed1975

Validity of the Internal-External Scale in its relationship with political position.

The study was designed to interpret previous reports of a relationship between left wing political position and externality on Rotter's (1966) Internal-External (I-E) Scale. I-E items phrased in the first person were associated with a criterion measure of locus of control, and externality on the scale predicted inferior performance in a skill-controlled task. However, political position was related to neither the criterion measure of locus of control nor to successful performance in a skill-controlled task. Thus, there was no evidence that political position was related to locus of control in spite of its relationship with the I-E Scale. There was discussion of implications for the validity of the I-E Scale and for studying relationships between personality and political variables.

Journal Article↗

PubMed1994

[Multinational validation of the Composite International Diagnostic Interview (CIDI)].

The Composite International Diagnostic Interview (CIDI) is a fully structured diagnostic interview developed by the "Joint Project of World Health Organization (WHO) and Alcohol, Drug Abuse, and Mental Health Administration (ADAMHA) on Diagnosis and Classification of Mental Disorders and Alcohol and Drug Related Problems". Its main features are: it is devised for use in epidemiological and trans-cultural fields, can be used also by non-medical staff, has a modular structure, and gives diagnoses simultaneously according to ICD-10 and DSM-III-R, covering respectively 39 and 32 diagnoses on Axis I. This paper explains the validation study which was performed simultaneously in 20 different Countries under the competence of WHO applying a traditional interviewer-observer protocol. The reliability indexes which were obtained are among the highest reported in the current literature for similar instruments, and good levels of trans-cultural applicability and feasibility were demonstrated. CIDI therefore proved to be a very precise and reliable diagnostic instrument.

Cross-Cultural Comparison↗

PubMed2005

Evaluation of alternative disk diffusion methods for detecting mecA-mediated oxacillin resistance in an international collection of staphylococci: validation report from the SENTRY Antimicrobial Surveillance Program.

To validate the current National Committee for Clinical Laboratory Standards recommendations of the cefoxitin disk as a preferred surrogate marker to detect oxacillin resistance in staphylococcal isolates, 304 staphylococcal isolates originating from 49 sites in 16 countries in the SENTRY Antimicrobial Surveillance Program (2003) were tested. Two hundred three Staphylococcus aureus and 101 coagulase-negative staphylococci (CoNS), of which >95% were bloodstream isolates, were evaluated by comparing the results of the National Committee for Clinical Laboratory Standards broth microdilution method for oxacillin with those of the disk diffusion test using oxacillin, cefoxitin and ceftizoxime disks. Discrepancies were resolved using the PBP2a latex agglutination test. For S. aureus, the cefoxitin disk performed without interpretive error followed by the ceftizoxime disk (1% major and 0.5% minor errors; > or =20 mm = susceptible); use of the oxacillin disk test had the highest error rates with 4.4% major and 1.5% minor errors, whereas the oxacillin minimal inhibitory concentration (MIC) test was 99.0% accurate. For CoNS, the oxacillin disk test had the highest error rate with 4.0% major errors, followed by the cefoxitin (3.0% major error rate) and the ceftizoxime (1% very major and 1% minor error: > or =20 mm = susceptible) disk tests. The oxacillin MIC test was also 99.0% accurate for CoNS testing. Modification of the ceftizoxime disk diffusion breakpoints for CoNS resulted in complete intermethod categorical agreement. The overall accuracy of the four tests was as follows: modified ceftizoxime disk (99.3%) > oxacillin MIC = cefoxitin disk (99.0%) > current ceftizoxime disk (98.4%) > oxacillin disk (94.7%). In conclusion, these results confirm the superior performance characteristics of cefoxitin and ceftizoxime disk tests as surrogate markers to detect oxacillin resistance; by using an international collection of clinically significant staphylococcal isolates, we also demonstrate its wide global application.

Bacterial Proteins↗

PubMed2002

Psychometric validation of the State Scale of Dissociation (SSD).

Although dissociative phenomena are often transient features of mental states, existing measures of dissociation are designed to measure enduring traits. A new present-state self-report measure, sensitive to changes in dissociative states, was therefore developed and psychometrically validated. Fifty-six items were formulated to measure state features, and sorted according to seven subscales: derealization, depersonalization, identity confusion, identity alteration, conversion, amnesia and hypermnesia. The State Scale of Dissociation (SSD) was administered with other psychiatric scales (DES, BDI, BAI, SCI-PANSS) to 130 participants with DSM-IV major depressive disorder schizophrenia, alcohol withdrawal, dissociative disorders and controls. In these sample populations, the SSD was demonstrated as a valid and reliable measure of changes in and the severity of dissociative states. Discriminant validity, content, concurrent, predictive, internal criterion-related, internal construct and convergent validities, and internal consistency and split-half reliability were confirmed statistically. Clinical observations of dissociative states, and their comorbidity with symptoms of depression and psychotic illness, were confirmed empirically. The SSD, an acceptable, valid and reliable scale measuring state features of dissociation at the time of completion, was obtained. This is a prerequisite for further investigation of correlations between changes in dissociative states and concurrent physiological parameters.

Adult↗

PubMed2001

Questionnaire-based mechanical exposure indices for large population studies--reliability, internal consistency and predictive validity.

OBJECTIVES: This study attempts to construct valid indices for mechanical exposure of the shoulder-neck region with relation to the development of shoulder-neck pain in a 1-year perspective study of a general population. METHODS: A comprehensive questionnaire was presented to 14 556 subjects aged 45 or 65 years and repeated after 12 months. Twenty-four questions concerning positions, movements, and manual materials handling were registered on a 3-point impact scale. Musculoskeletal problems were reported on a slightly modified version of the Standardized Nordic Questionnaire for the Analysis of Musculoskeletal Symptoms. Test-retest stability after 2 weeks was calculated for 232 consecutive participants. Based on mechanistic theories, 4 exposure indices were formed. Another 5 constructs were obtained by factor analysis. RESULTS: All the indices showed good test-retest stability, and 5 of them had very good internal consistency. Due to overlaps between the indices, 2 indices stood out as having unique properties. One of them concerned mainly postures and the other dealt primarily with measured lifting. However, the latter was not related to the shoulder-neck pain outcome when adjusted for the posture index. The posture index showed an exposure-effect relationship with the outcome. The job titles implied a large degree of exposure misclassification. CONCLUSIONS: The posture index is recommended as a mechanical exposure index for analyses of interaction with other possible determinants of shoulder-neck pain (ie, psychosocial factors). The use of such an index instead of job titles in large population studies will reduce the risk of misclassification.

Analysis of Variance↗

PubMed2005

Assessment of capacity for myoelectric control: a new Rasch-built measure of prosthetic hand control.

OBJECTIVE: To report the results from a Rasch rating scale analysis of the Assessment of Capacity for Myoelectric Control (ACMC) implemented to evaluate internal scale validity, person response validity, separation reliability, targeting and responsiveness of the measures over time. DESIGN: Longitudinal data (18 months) from a prospective study of development of capacity for myoelectric control in children and adults were used for the analysis. PATIENTS: A consecutive sample of 75 subjects (43 males, 32 females) with upper limb reduction deficiency or amputation and myoelectric prosthetic hands referred for occupational therapy from September 2000 to March 2002. Participants' ages ranged from 2 to 57 years. METHODS: Outcome measure was the ACMC. Occupational therapists completed 210 assessments at an arm prosthesis centre in Sweden. A two-faceted rating scale analysis of the data was performed. RESULTS: All 30 ACMC items and 96.2% of participants demonstrated goodness-of-fit to the rating scale model for the ACMC. Separation and SE values suggested adequate reliability of the item and person estimates. CONCLUSION: The items demonstrated internal scale validity and the participants demonstrated person response validity. The ACMC was well targeted and sensitive enough to detect expected change in ability.

Activities of Daily Living↗

PubMed1999

Standard cost lists for healthcare in Canada. Issues in validity and inter-provincial consolidation.

A standard cost list is a listing of recommended costs for a selected group of services. Standard costs are used in economic evaluation studies to eliminate that proportion of cost differences between interventions that are due to cost differences between providers. In this article we provide a summary of cost lists for pharmaceutical economic evaluation purposes which have been developed in 2 provinces in Canada-Alberta and Manitoba. We then assess these 2 lists from 2 different viewpoints. First, we developed criteria for the internal and external validity of costs and, in light of these validity criteria, we assessed how the 2 standard cost lists compared with the 'ideal' measure of long run marginal costs. Second, we identified the criteria for the inter-provincial consolidation of standard cost measures (in order to develop a single, consolidated cost list); in light of these criteria, we assessed whether the degree to which the 2 separate lists could be consolidated. The lists achieved a considerable degree of external validity, but fared less well in terms of internal validity. However, these results depend on the 'ideal' measure of cost which is used. The lists, in the forms which were developed, are not easily consolidated into a single list. Further refined cost data would be needed in order to achieve consolidation.

Alberta↗

PubMed1994

The international normalized ratio and uncertainty. Validation of a probabilistic model.

The motivation behind the creation of the International Normalized Ratio (INR) was to improve interlaboratory comparison for patients on anticoagulation therapy. In principle, a laboratory that reports the prothrombin time (PT) as an INR can standardize its PT measurements to an international reference thromboplastin. Using probability theory, the authors derived the equation for the probability distribution of the INR based on the PT, the International Sensitivity Index (ISI), and the geometric mean PT of the reference population. With Monte Carlo and numeric integration techniques, the model is validated on data from three different laboratories. The model allows computation of confidence intervals for the INR as a function of PT, ISI, and reference mean. The probabilistic model illustrates that confidence in INR measurements degrades for higher INR values. This occurs primarily as a result of amplification of between-run measurement errors in the PT, which is inherent in the mathematical transformation from the PT to the INR. The probabilistic model can be used by any laboratory to study the reliability of its own INR for any measured PT. This framework provides better insight into the problems of monitoring oral anticoagulation.

Evaluation Studies as Topic↗

PubMed2002

Behavior change intervention research in healthcare settings: a review of recent reports with emphasis on external validity.

BACKGROUND: Information to judge both the internal and external validity of health behavior research conducted in healthcare settings is vital to translate research findings to practice. This paper reviews the extent to which this research has reported on elements of internal and external validity, with emphasis on the extent to which research has been conducted in representative settings with representative populations. METHODS: A comprehensive review was conducted of controlled interventions for dietary change, physical activity, or smoking cessation conducted in healthcare settings and published in 12 leading health behavior journals between 1996 and 2000. Using the RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework, the characteristics and results of these studies were summarized to document the extent to which intervention reach, adoption, implementation, and maintenance were reported and what has been learned about each of these dimensions. RESULTS: A total of 36 studies qualified for review. Participation rates among eligible patients were reported in 69% of studies and were generally quite high; in contrast, only 30% of studies reported on participation rates among either healthcare settings or providers. Implementation data were reported in 77% of the studies and these rates were generally high, with the caveat that intervention was often delivered by paid research staff. Long-term maintenance results were reported very consistently at the individual level, but program continuation was almost never reported at the setting level. CONCLUSIONS: We conclude that a much stronger emphasis needs to be placed on the representativeness of providers and settings that are studied. Examples of how this can be done and recommendations for future research are provided.

Feeding Behavior↗

PubMed2000

Validation and implementation of an internal standard in comet assay analysis.

The comet assay is widely used to detect DNA damage in single cells. However, only moderate attention has been paid to the experimental variability of this assay, especially during electrophoresis. To take into account this variation and to be able to compare measurements from different electrophoretic runs, as would be necessary when large numbers of samples need to be analysed, it is important to integrate an internal standard into the assay. This study presents a first step in the validation and implementation of an internal standard in the alkaline comet assay. Untreated and ethyl methanesulfonate treated cells (K562 human erythroleukemia cell line) were used as negative and positive internal standards, respectively, in each electrophoresis run. Three steps were followed: (1) assessment of the different levels of variability which may influence the damage levels of the internal standards, (2) evaluation of the variability across separate electrophoresis runs on the quantification of DNA damage in the internal standards by three experimenters involved in different studies and (3) proposal of an adequate calculation system to integrate the internal standards into test sample data. The application of the two proposed models to samples from a human biomonitoring study is presented. The model which calibrates the measurements against the negative internal standard is the most useful since this negative standard was the most stable across experiments and among the three experimenters. The percentage of DNA in the tail is the most appropriate parameter to analyse induced DNA damage, because its interelectrophoresis and interexperimenter variation is less pronounced than that of tail length.

Comet Assay↗

PubMed1993

The factor structure of ADHD items in DSM-III-R: internal consistency and external validation.

Previous research employing factor-analytic procedures to study the underlying dimensions of DSM-III attention deficit disorder with hyperactivity (ADDH) symptoms have consistently supported a two-factor model. Revision of the structure of the ADHD diagnosis in DSM-III-R, as well as inclusion of new items, has raised the question of comparability of the two diagnoses. To explore the significance of these changes, teacher ratings of DSM-III ADDH items and DSM-III-R ADHD items of 85 nonreferred school children were factor-analyzed to determine their underlying factor structures. A similar two-factor solution was obtained for each diagnostic scale. The factors consisted of items believed to reflect inattention and hyperactivity-impulsivity constructs. These factors were further evaluated against results of a cognitive test battery to ascertain whether objective, external validation could be demonstrated. The hyperactivity-impulsivity factor scores were related to continuous performance test measures of response inhibition, while inattention-disorganization factor scores were related to measures of attention and visual search. Implications for assessment and diagnosis of ADHD are discussed.

Attention Deficit Disorder with Hyperactivity↗