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Reliability and validity of the Functional Assessment of Cancer Therapy-Breast quality-of-life instrument.

PURPOSE: This is the first published report on the validation of the Functional Assessment of Cancer Therapy-Breast (FACT-B), a 44-item self-report instrument designed to measure multidimensional quality of life (QL) in patients with breast cancer. The FACT-B consists of the FACT-General (FACT-G) plus the Breast Cancer Subscale (BCS), which complements the general scale with items specific to QL in breast cancer. The FACT-B was developed with an emphasis on patients' values and brevity and is available in nine languages. METHODS AND RESULTS: Two validation samples were used for this report. The first (n = 47) was tested twice over a 2-month period to assess sensitivity to change. Significant sensitivity to change in performance status rating (PSR) was demonstrated for the FACT-B total score, the Physical Well-Being (PWB) subscale, the Functional Well-Being (FWB) subscale, and the BCS. Sensitivity to change in QL as measured by the Functional Living Index-Cancer (FLIC) was documented in the FACT-B total score, PWB, FWB, and Emotional Well-Being (EWB). Additional validity and reliability data were obtained from a larger sample (n = 295). The alpha coefficient (internal consistency) for the FACT-B total score was high (alpha = .90), with subscale alpha coefficients ranging from .63 to .86. Evidence supported test-retest reliability, as well as convergent, divergent, and known groups validity. CONCLUSION: The FACT-B is appropriate for use in oncology clinical trials, as well as in clinical practice. It demonstrates ease of administration, brevity, reliability, validity, and sensitivity to change.

Adult↗

A validity scale sign calling for caution in the interpretation of MMPIs among psychiatric inpatients.

Three expert MMPI judges classified 100 psychiatric inpatients as psychotic or non-psychotic on the basis of their MMPIs. Validity scale data, as well as clinical scale scores, were included for 50 of the profiles, while the validity scale scores were withheld from the judges for the remaining 50 profiles. Within each of the above two groups, half had a "positive" validity scale sign (a defensive validity scale configuration defined as L or K greater than or equal to 70, or both greater than or equal to 60) and half had a negative validity scale sign, indicating a lack of defensiveness. Using actual diagnosis as the external criterion, results indicated that the majority of defensive psychotic patients produced clinical scale configurations which appeared nonpsychotic to the judges. Conversely, the majority of nondefensive nonpsychotics produced psychotic-appearing clinical scale configurations. These two types of test misses suggest that K corrections on MMPI scales relating to psychosis are not optimal for psychiatric inpatients. Guidelines were developed for interpreting defensive profiles.

Defense Mechanisms↗

The Bender-Gestalt psychopathology scale: failure to infer validity in a school-aged sample.

The concurrent validity of Hutt's (1977) empirical psychopathology scale of the Bender Visual-Motor Gestalt Test was evaluated among three groups of younger school-aged children within the 7-to-10- year age range (M = 109.1): adjustment disordered, conduct disordered, and nonclinical controls (n = 40/group). Excellent interscorer reliability was achieved with approximately 2 hr of self-study of the scoring manual. Although the conduct-disordered group was significantly more immature on Koppitz' Developmental Scoring System, there were no significant differences among groups on the psychopathology scale when visual-motor development was covaried (M = 50.5). This was an unexpected result, given Hutt's initial validation study among school-aged children. The psychopathology scale was not inferred to be valid among adolescents in the only known concurrent validation study. Pending supportive validation research, the psychopathology scale should not be employed in the clinical assessment of younger school-aged children.

Journal Article↗

Sociotropy and autonomy: preliminary evidence for construct validity using TAT narratives.

In this investigation, we evaluated the construct validity of sociotropy and autonomy as assessed by the revised Personal Style Inventory (PSI; Robins et al., 1994). Stories given to 6 cards of the Thematic Apperception Test (Murray, 1943) were coded for need for Achievement (McClelland, Atkinson, Clark, & Lowell, 1953) and need for Affiliation (Heyns, Veroff, & Atkinson, 1958). These scores were correlated with PSI Sociotropy and Autonomy, along with their component subscales. The construct validity of Sociotropy, Autonomy, and 5 of 6 component subscales were supported as hypoth sized. Consistent with past research, there was no support for the construct validity of the Perfectionism/Self-Criticism subscale of Autonomy. In addition, separate analyses by gender suggested that the construct validity of sociotropy may be greater for women than for men. The results represent an important finding in that nonquestionnaire measures of interpersonal and achievement-related concerns were found to support the validity of the PSI, a need identified by the questionnaire's authors.

Adolescent↗

Overreport on the MCMI-III: concurrent validation with the MMPI-2 using a psychiatric inpatient sample.

The MCMI-III (Millon, Davis, & Millon, 1997) is a widely used measure of personality often used in inpatient psychiatric settings. Although patients in such settings often overreport or exaggerate their symptoms, relatively little is known about how such a response set presents on the validity indexes of the MCMI-II. In this study, we used a sample of 191 psychiatric inpatients and compared MCMI-III modifier indices (Disclosure, Desirability, and Debasement) with the validity measures (L, F, Fb, F(p), K, and F - K) of the MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989). In addition, the MCMI-III Disclosure Index (Scale X, which imposes a set cutoff score for invalidity due to overreport) was compared to several cutoff scores on the validity scales of the MMPI-2. Although the MCMI-III indexes generally performed as expected, the MCMI-III had a very high tolerance for overreport. When contrasted with MMPI-2 F scale, the MCMI-II Disclosure Index (which gauges overreport) remained valid until scores on MMPI-2 F scale approached a T score of 120. In addition, the Disclosure Index was at the upper end or slightly exceeded the highest recommended cutoff scores on all other MMPI-2 validity scales except F - K. Clinicians using the MCMI-III alone are cautioned to consider the high tolerance the MCMI-III has for overreport.

Adult↗

The Spastic Paraplegia Rating Scale (SPRS): a reliable and valid measure of disease severity.

OBJECTIVE: To develop and evaluate a clinical Spastic Paraplegia Rating Scale (SPRS) to measure disease severity and progression. METHODS: A 13-item scale was designed to rate functional impairment occurring in pure forms of spastic paraplegia (SP). Additional symptoms constituting a complicated form of SP are recorded in an inventory. Two independent patient cohorts were evaluated in a two-step validation procedure. RESULTS: Application of SPRS requires less than 15 minutes and does not require any special equipment, so it is suitable for an outpatient setting. Interrater agreement of SPRS was high (intraclass correlation coefficient = 0.99). Reliability was further supported by high internal consistency (Cronbach alpha = 0.91). SPRS values were almost normally distributed without apparent floor or ceiling effect. Construct validity was shown by high correlation of SPRS to Barthel Index and the International Cooperative Ataxia Rating Scale (convergent validity) and low correlation to Mini-Mental Status Examination (discriminant validity). CONCLUSION: The Spastic Paraplegia Rating Scale is a reliable and valid measure of disease severity.

Adolescent↗

Reliability and validity of two self-report measures of impairment and disability for MS. North American Research Consortium on Multiple Sclerosis Outcomes Study Group.

OBJECTIVE: To describe the results of a multicenter study that validated two new patient-reported measures of neurologic impairment and disability for use in MS clinical research. BACKGROUND: Self-reported data can provide a cost-effective means to assess patient functioning, and can be useful for screening patients who require additional evaluation. METHODS: Thirteen MS centers from the United States and Canada implemented a cross-sectional validation study of two new measures of neurologic function. The Symptom Inventory is a measure of neurologic impairment with six subscales designed to correlate with localization of brain lesion. The Performance Scales measure disability in eight domains of function: mobility, hand function, vision, fatigue, cognition, bladder/bowel, sensory, and spasticity. Measures given for comparison included a neurologic examination (Expanded Disability Status Scale, Ambulation Index, Disease Steps) as well as the patient-reported Health Status Questionnaire and the Quality of Well-being Index. Participants included 274 MS patients and 296 healthy control subjects who were matched to patients on age, gender, and education. RESULTS: Both the Symptom Inventory and the Performance Scales showed high test-retest and internal consistency reliability. Correlational analyses supported the construct validity of both measures. Discriminant function analysis reduced the Symptom Inventory to 29 items without sacrificing reliability and increased its discriminant validity. The Performance Scales explained more variance in clinical outcomes and global quality of life than the Symptom Inventory, and there was some evidence that the two measures complemented each other in predicting Quality of Well-being Index scores. CONCLUSIONS: The Symptom Inventory and the Performance Scales are reliable and valid measures.

Adult↗

Total neuropathy score: validation and reliability study.

OBJECTIVE: To determine the validity and reliability of the total neuropathy score (TNS) in normal subjects and in subjects with diabetic polyneuropathy. BACKGROUND: Clinical research in peripheral neuropathy requires validated outcome measures. Multiple outcome measures have been used in clinical trials, including symptom measures, functional scales, quantitative clinical examinations, nerve conduction studies, computerized sensory examinations, and nerve biopsy. Each of these measures has its strengths and weaknesses. In two previous studies of toxic neuropathy from chemotherapeutic agents, the authors used the TNS as the outcome measure. The TNS combines information obtained from grading of symptoms, signs, nerve conduction studies, and quantitative sensory tests, and provides a single measure to quantify neuropathy. METHODS: The authors measured the inter- and intrarater reliability of the TNS and preformed a cross-sectional validation study of the TNS and its subscales with the Mayo Clinic measures of neuropathy, neuropathy symptom score (NSS), and the neurologic impairment score (NIS) in five healthy control subjects and 30 individuals with varying severities of diabetic polyneuropathy. RESULTS: Inter- and intrarater reliability of the TNS was excellent (0.966 and 0.986 respectively). The cross-sectional validation study showed excellent correlations among all measures of neuropathy. CONCLUSIONS: The total neuropathy score is a validated measure of peripheral nerve function and could be used as an end point for clinical trials of peripheral neuropathy.

Adolescent↗

Validation of biological markers for quantitative risk assessment.

The evaluation of biological markers is recognized as necessary to the future of toxicology, epidemiology, and quantitative risk assessment. For biological markers to become widely accepted, their validity must be ascertained. This paper explores the range of considerations that compose the concept of validity as it applies to the evaluation of biological markers. Three broad categories of validity (measurement, internal study, and external) are discussed in the context of evaluating data for use in quantitative risk assessment. Particular attention is given to the importance of measurement validity in the consideration of whether to use biological markers in epidemiologic studies. The concepts developed in this presentation are applied to examples derived from the occupational environment. In the first example, measurement of bromine release as a marker of ethylene dibromide toxicity is shown to be of limited use in constructing an accurate quantitative assessment of the risk of developing cancer as a result of long-term, low-level exposure. This example is compared to data obtained from studies of ethylene oxide, in which hemoglobin alkylation is shown to be a valid marker of both exposure and effect.

Biomarkers↗

13th Meeting of the Scientific Group on Methodologies for the Safety Evaluation of Chemicals (SGOMSEC): validation and acute toxicity testing.

Scientific principles demand that before newly developed alternative methods for safety testing are fully embraced by the industrial or regulatory community, they reliably and reproducibly predict the designated toxic end point. The process used to determine reliability and reproducibility is termed validation, and it generally culminates with a highly controlled, blinded study using multiple chemicals and laboratories. It is imperative that the validation study is designed to confirm the previously established reproducibility and predictive power of the assay. Much has been learned recently about the practical aspects of validation through investigation of alternative methods for acute toxicity testing, i.e., those methods that assess acute systemic toxicity, skin irritation, and eye irritation. Although considerable progress has been made--many alternative tests are now commonly used in various industrial settings--there have been few tests that have successfully passed a complete validation. Some of the barriers to successful validation have been a) lack of high-quality, reproducible animal data; b) insufficient knowledge of the fundamental biologic processes involved in acute toxicity; and c) the development of truly robust in vitro assays that can accurately respond to materials with a wide range of chemical and physical characteristics. It is recommended that to progress in the areas of eye and skin irritation we need to expand our knowledge of toxic markers in humans and the biochemical basis of irritation; progress in the area of acute systemic toxicity will require the development of in vitro models to determine gastrointestinal uptake, blood-brain barrier passage, and biotransformation.

Animal Testing Alternatives↗

Development and validation of the medication regimen complexity index.

BACKGROUND: Medication regimen attributes, such as the number of drugs, dosage frequency, administration instructions, and the prescribed dosage forms, have been shown to influence patient outcomes. No single tool for quantifying the complexity of general medication regimens has been published in the medical literature. OBJECTIVE: To develop and validate a tool to quantify the complexity of prescribed medication regimens. METHODS: Literature findings and the expertise of the authors were used for developing the tool. Eight pharmacy researchers helped in establishing the tool's face and content validity. The new tool was tested on 134 medication regimens from patients with moderate to severe chronic obstructive pulmonary disease. Six regimens with a spread of scores on the tool were presented to a 5-member expert panel that subjectively ranked these regimens to confirm the tool's criterion-related validity. The relationships between scores on the tool and various independent variables were tested to judge the tool's construct validity. Two raters scored 25 regimens using the tool to test its inter-rater and test-retest reliabilities. RESULTS: A 65-item Medication Regimen Complexity Index (MRCI) was developed. The expert panel had strong agreement (Kendall's W = 0.8; p = 0.001) on their individual rankings of the 6 regimens. The panel's consensus ranking had perfect correlation with the MRCI ranking. The total MRCI score had significant correlation with the number of drugs in the regimen (Spearman's Rho = 0.9; p < 0.0001), but not with the age and gender of the patients. Inter-rater and test-retest reliabilities for the total score and scores for individual sections on the MRCI were > or = 0.9. CONCLUSIONS: The MRCI is a reliable and valid tool for quantifying drug regimen complexity with potential applications in both practice and research.

Clinical Protocols↗

The predictive and discriminant validity of the zone of proximal development.

BACKGROUND: Dynamic measurement procedures are supposed to uncover the zone of proximal development and to increase predictive validity in comparison to conventional, static measurement procedures. AIMS: Two alternative explanations for the discrepancies between static and dynamic measurements were investigated. The first focuses on Vygotsky's learning potential theory, the second considers the role of anxiety tendency during test taking. If test anxious tendencies are mitigated by dynamic testing procedures, in particular the availability of assistance, the concept of the zone of proximal development may be superfluous in explaining the differences between the outcomes of static and dynamic measurement. SAMPLE: Participants were students from secondary education in the Netherlands. They were tested repeatedly in grade three as well as in grade four. Participants were between 14 and 17 years old; their average age was 15.4 years with a standard deviation of .52. METHOD: Two types of mathematics tests were used in a longitudinal experiment. The first type of test consisted of open-ended items, which participants had to solve completely on their own. With the second type of test, assistance was available to participants during the test. The latter so-called learning test was conceived of as a dynamic testing procedure. Furthermore, a test anxiety questionnaire was administered repeatedly. Structural equation modelling was used to analyse the data. RESULTS: Apart from emotionality and worry, lack of self-confidence appears to be an important constituent of test anxiety. The learning test appears to contribute to the predictive validity of conventional tests and thus a part of Vygotsky's claims were substantiated. Moreover, the mere inclusion of a test anxiety factor into an explanatory model for the gathered data is not sufficient. Apart from test anxiety and mathematical ability it is necessary to assume a factor which may be construed as mathematics learning potential. CONCLUSION: The results indicate that the observed differences between a conventional, static testing procedure and an experimental, dynamic testing procedure for mathematics cannot be explained sufficiently by a differential bias towards test anxiety. The dynamic testing approach renders scores which add to the predictive validity of conventional testing procedures. Since this gain in predictive validity is not a result of the removal of bias towards test anxiety, this result should be understood as supportive for the validity of the concept of the zone of proximal development.

Adolescent↗

Quality of life (Spain and France): validation of the chronic venous insufficiency questionnaire (CIVIQ).

A health-related quality of life (HRQOL) assessment is particularly necessary for patients with chronic venous insufficiency (CVI), as is an assessment of the objective signs (edema, dilated veins, ulceration and other lesions). A comprehensive 3-year research program was undertaken in France to construct and validate the Chronic Venous Insufficiency Questionnaire (CIVIQ), a questionnaire designed specifically to evaluate the quality of life for CVI sufferers. The next step was to implement a program of cross-cultural validation in several countries. Translation into Spanish was undertaken following international guidelines. Face validity was verified with a pilot test among 12 Spanish patients. Psychometric validation was performed in Spain (n = 476 patients with CVI). The Spanish CIVIQ demonstrated very good internal consistency, high reproducibility and responsiveness, as well as longitudinal clinical validity. It appears to be a valuable instrument for assessing improvement in patient quality of life in response to both therapy in clinical practice and clinical trials.

Chronic Disease↗

Radiometric validation of NASA's Ames Research Center's Sensor Calibration Laboratory.

The National Aeronautics and Space Administration's (NASA's) Ames Research Center's Airborne Sensor Facility (ASF) is responsible for the calibration of several airborne Earth-viewing sensor systems in support of NASA Earth Observing System (EOS) investigations. The primary artifact used to calibrate these sensors in the reflective solar region from 400 to 2500 nm is a lamp-illuminated integrating sphere source. In September 1999, a measurement comparison was made at the Ames ASF Sensor Calibration Facility to validate the radiometric scale, establish the uncertainties assigned to the radiance of this source, and examine its day-to-day repeatability. The comparison was one of a series of validation activities overseen by the EOS Calibration Program to ensure the radiometric calibration accuracy of sensors used in long-term, global, remote-sensing studies. Results of the comparison, including an evaluation of the Ames Sensor Calibration Laboratory (SCL) measurement procedures and assigned radiometric uncertainties, provide a validation of their radiometric scale at the time of the comparison. Additionally, the maintenance of the radiance scale was evaluated by use of independent, long-term, multiyear radiance validation measurements of the Ames sphere source. This series of measurements provided an independent assessment of the radiance values assigned to integrating sphere sources by the Ames SCF. Together, the measurements validate the SCF radiometric scale and assigned uncertainties over the time period from September 1999 through July 2003.

Journal Article↗

Considerations for target validation and industrial approaches.

Target validation in health and disease integrates the modulation of a certain molecular target with an expected biological/biochemical/physiological or pathophysiological response or effect. The current state-of-the-art in target validation requires the interface of multiple complementary approaches and technologies to define the mechanistic connectivity between a molecular target and underlying micro- and macrobiotic processes. Target validation also represents the basis for "drug target validation" with focus on therapeutic applications. The concepts of "target validation" and "drug-based therapeutic intervention" continue to coevolve as new classes of therapeutic agents and delivery systems emerge and enable us to target or modulate previously inaccessible molecular entities.

Animals↗

Research issues and strategies for genomic and proteomic biomarker discovery and validation: a statistical perspective.

The development and validation of clinically useful biomarkers from high-dimensional genomic and proteomic information pose great research challenges. Present bottlenecks include: that few of the biomarkers showing promise in initial discovery were found to warrant subsequent validation; and biomarker validation is expensive and time consuming. Biomarker evaluation should proceed in an orderly fashion to enhance rigor and efficiency. A molecular profiling approach, although promising, has a high chance of yielding biased results and overfitted models. Specimens from cohorts or intervention trials are essential to eliminate biases. The high cost for biomarker validation motivates some novel study design features, including sequential filtering and DNA pooling. For data analysis, logistic regression (in particular, boosting logistic regression) has features of robustness against model misspecification, and has resistance to model overfitting. Model assessment and cross-validation are critical components of data analysis. Having an independent test set is a vital feature of study design.

Biomarkers, Tumor↗

Effects of warning validity and proximity on responses to warnings.

The effects of a warning's validity and display characteristics on the responses to binary warnings were studied in a categorization task that resembled the control of a simulated production environment. Students performed a visual signal detection task and were aided by a binary warning indicator. Experimental conditions differed in the validity of the warning and its proximity to the judged stimulus. Participants' performance improved over the course of the experiment, and they partly adjusted their responses to the validity of the warnings but continued to respond to nonvalid warnings throughout the experiment. It was particularly difficult to ignore the nonvalid information when it was integrated with the continuous information. There was evidence for nonoptimal use of the information from the warning system, whether it was valid or not valid. The results indicate a possible distinction between two dimensions of users' trust in warning systems: compliance and reliance. Actual or potential implications of this research include improved warning design based on analysis of system and operator characteristics.

Analysis of Variance↗

The comparative validity of eleven alcoholism typologies.

OBJECTIVE: This study directly compared the clinical validity of 11 empirically defined alcoholism typologies to determine whether some typologies are clinically more valid than others. METHOD: A sample of 360 hospitalized alcoholic men were extensively evaluated at entry into the study and again 1 year later. Twenty-three measures of clinical validity were employed; 15 were postdictive and 8 were predictive. Postdictive retrospective measures obtained at entry into the study included family history, age of onset and lifetime course characteristics associated with alcoholism severity, general psychopathology and psychosocial functioning. Predictive outcome measures drawn from information obtained during the 1-year follow-up included: abstinence, alcoholism severity and clinician ratings of outcome. The measures were subjected to various statistical analyses, including factor analysis. RESULTS: We found that all of the alcoholism typologies met at least 7 of the 23 a priori measures of clinical validity. The correlations between these conceptually and methodologically disparate typologies were often striking. Exploratory factor analysis, which explained 35% of the variance, suggested three possible underlying dimensions to account for the overlap among typologies: (1) age and its correlates, including age-of-alcoholism onset; (2) "pure" alcoholism versus psychiatrically heterogeneous alcoholism that encompassed antisocial personality disorder; and (3) current severity of psychiatric distress, impairment and dysfunction. CONCLUSIONS: No single method of subtyping alcoholics clearly emerged as superior. All demonstrated some degree of predictive and postdictive clinical validity. Most methods of subtyping correlated positively with each other at moderate, but typically significant, levels.

Adult↗