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PubMed2000

Development of two instruments measuring social support for siblings of children with cancer.

The literature on childhood cancer provides a very limited understanding of healthy siblings' perceptions of supportive interventions during the childhood cancer experience. The purpose of this article is to discuss the development of the Nurse-Sibling Social Support Questionnaire (NSSSQ). Instrument methodology for the study involved item development, face and content validation, and internal consistency reliability as described by Hockenberry-Eaton, Manteuffel, and Bottomley (1997). Item development for the research instrument evolved from an extensive review of the literature and clinical experience of the principal investigator. Content validity of the instrument was accomplished by five experienced pediatric oncology nurses according to the methodology described by Lynn (1986). Using the content validity index, each nurse rated each item as either 4 or 5, indicating 100% agreement among experts that these items measured the concept of social support. Readability for the instrument was determined by using a computerized program. Results showed that readability was concordant with the grade school level for all items. Twenty-five school-age siblings of children with cancer and their mothers were asked to complete the questionnaire. Instrument completion was accomplished in less than 1 hour. The NSSSQ showed high internal consistencies (alpha coefficients >.90). Results indicated that siblings' perceptions of social support differed from those of their mothers. Siblings perceive emotional and instrumental support as greater in importance, whereas mothers perceive emotional and informational support as more beneficial to siblings. Support issues for siblings of children with cancer have been difficult to assess because of the lack of appropriate instruments. This study finding provides exploratory evidence to suggest that the new instrument can help measure siblings' perceptions of social support during the childhood cancer experience.

Adolescent↗
PubMed1991

Assessment of current International Federation of Gynecology and Obstetrics staging of vulvar carcinoma relative to prognostic factors for survival (a Gynecologic Oncology Group study).

Analysis of 588 patients with vulvar carcinoma delineated four risk groups by the proportional hazards model. Groin node status (laterality and number positive) and lesion diameter were the only two important independent prognostic factors. The 5-year relative survival rates were 98%, 87%, 75%, and 29% for the risk group categories of minimal (negative groin nodes and lesion diameter less than or equal to 2 cm), low (one positive groin node and lesion diameter less than or equal to 2 cm or negative groin nodes and fewer than two lesions less than or equal to 8 cm diameter), intermediate (negative groin nodes and lesion diameter greater than 8 cm diameter, one positive groin node and lesion diameter greater than 2 cm, or two unilaterally positive groin nodes and lesion diameter less than or equal to 8 cm), and high (three or more positive groin nodes or two bilaterally positive groin nodes), respectively. Applying the International Federation of Gynecology and Obstetrics staging (1988) to these data discriminated risk of death (caused by recurrent vulvar cancer); the 5-year rates were 98%, 85%, 74%, and 31% for stages I, II, III, and IV, respectively. However, within International Federation of Gynecology and Obstetrics stage III there were 47 low-, 95 intermediate-, and 28 high-risk patients with relative survivals of 95%, 74%, and 34%, respectively. Overall, this assessment validates current International Federation of Gynecology and Obstetrics vulvar carcinoma staging, but further refinements are warranted in stage III.

Carcinoma, Squamous Cell↗
PubMed2002

DarT: The embryo test with the Zebrafish Danio rerio--a general model in ecotoxicology and toxicology.

The acute fish test is an animal test whose ecotoxicological relevance is worthy of discussion. The primary aim of protection in ecotoxicology is the population and not the individual. Furthermore the concentration of pollutants in the environment is normally not in the lethal range. Therefore the acute fish test covers solely the situation after chemical spills. Nevertheless, acute fish toxicity data still belong to the base set used for the assessment of chemicals. The embryo test with the zebrafish Danio rerio (DarT) is recommended as a substitute for the acute fish test. For validation an international laboratory comparison test was carried out. A summary of the results is presented in this paper. Based on the promising results of testing chemicals and waste water the test design was validated by the DIN-working group "7.6 Fischei-Test". A normed test guideline for testing waste water with fish is available. The test duration is short (48 h) and within the test different toxicological endpoints can be examined. Endpoints from the embryo test are suitable for QSAR-studies. Besides the use in ecotoxicology the introduction as a toxicological model was investigated. Disturbance of pigmentation and effects on the frequency of heart-beat were examined. A further important application is testing of teratogenic chemicals. Based on the results DarT could be a screening test within preclinical studies.

Animal Rights↗
PubMed1997

Self-reported assessment of dry eye in a population-based setting.

PURPOSE: To report on a subjective dry eye assessment method for use in large-scale research, to evaluate its application in a population-based study of dry eye among elderly persons in the United States, and to apply novel techniques to improve simple questionnaire item summaries. METHODS: A dry eye questionnaire was administered to a population-based sample of 2520 volunteers ages 65 to 84 years in Salisbury, Maryland. Individual symptoms and signs, counts of symptoms and signs, and latent class model summary of item responses were evaluated for validity and internal consistency. RESULTS: Approximately 15% of participants reported experiencing one or more of six dry eye symptoms often or all the time; 20% reported experiencing three or more symptoms sometimes, often or all the time. Four groups were derived on the basis of symptomatology, using latent class analysis. The groups exhibited face validity, revealed symptom patterns that added specificity to simple symptom counts, and were qualitatively similar when derived separately within population subgroups. Internal consistency was moderate (Cronbach's alpha = 0.61), indicating some variability in reporting. CONCLUSIONS: Dry eye symptoms are commonly reported in a representative elderly population. Symptom data were moderately consistent, suggesting their usefulness for dry eye assessment if properly summarized. A latent class summary revealed biologically meaningful summary patterns of symptoms reported in this population and holds promise for use in risk factor investigations and in clinical trials.

Aged↗
PubMed2000

Naturalistic assessment of functional performance in school settings: reliability and validity of the School AMPS scales.

The School Assessment of Motor and Process Skills (School AMPS) is an assessment tool designed to be used by occupational therapists to measure the effectiveness of a student's ability to perform school tasks in naturalistic classroom settings. Rater reliability, internal scale validity, and person response validity of the School AMPS was investigated by examining the goodness-of-fit of raters, motor and process skill items, and students to the many-faceted Rasch model used in the development of the School AMPS. Five of six raters demonstrated acceptable goodness-of-fit (MnSq < or = 1.4 and z < 2). All 36 motor and process skill items demonstrated acceptable goodness-of-fit. Of the 208 students in the study, 93.7% demonstrated acceptable goodness-of-fit on the School AMPS motor scale and 88.9% demonstrated acceptable goodness-of-fit on the School AMPS process scale. The results of this study support the rater reliability, scale validity, and person response validity for the School AMPS as a tool to be used to evaluate the effectiveness of student performance of school tasks in the classroom setting.

Activities of Daily Living↗
PubMed2006

Development and validation of the Beliefs and Behaviour Questionnaire (BBQ).

OBJECTIVE: To develop and validate a questionnaire to screen for potential nonadherence in patients with chronic ailments. METHODS: Themes from qualitative interviews with chronic obstructive pulmonary disease patients were used in developing content of the questionnaire. The questionnaire was distributed to 525 ambulatory patients with chronic lung diseases. Principal components analysis was performed to identify the subscales in the questionnaire. Internal consistency, validity and stability of the subscales were also evaluated. RESULTS: The 30-item Beliefs and Behaviour Questionnaire (BBQ) measures beliefs, experiences and adherent behaviour on five-point Likert-type scales. Two hundred and eighty patients (53.3%) with a mean age of 71.1 years responded to the questionnaire. The 'beliefs' section had a two-factor solution-'confidence' and 'concerns' with internal consistencies of 0.82 and 0.45, respectively. The two domains identified from the section 'experiences'-satisfaction' and 'disappointment' had internal consistencies of 0.85 and 0.52, respectively. The 'behaviour' section, separately entitled the Tool for Adherence Behaviour Screening (TABS), had a two-factor solution--'adherence' and 'nonadherence', with internal consistencies of 0.80 and 0.59, respectively. All the domains demonstrated comparable reliabilities across two different patient populations. Their temporal stabilities ranged between 0.62 and 0.94. CONCLUSION: The validity, reliability and utility of the BBQ and the TABS, a sub-scale of the BBQ that screens both intentional and unintentional nonadherence to pharmacological and non-pharmacological disease management, have been established. PRACTICE IMPLICATIONS: The BBQ and the TABS have potential applications in screening adherence beliefs, experiences and behaviour in both clinical practice and research.

Aged↗
PubMed2000

Prediction of long-term response to recombinant human growth hormone in Turner syndrome: development and validation of mathematical models. KIGS International Board. Kabi International Growth Study.

It has become common practice to apply GH treatment in short Turner syndrome patients with the objective of promoting growth. The variability in response and the high costs of this treatment demand the individualization and optimization of therapy. Based on 686 prepubertal Turner patients from the Kabi International Growth Study (KIGS; Pharmacia & Upjohn, Inc. International Growth Database), we undertook a multiple regression analysis of height velocity (centimeters per yr) by using various parameters of potential relevance. Derived prediction models for the first 4 yr of GH treatment were validated with 76 additional KIGS patients and 81 patients from Tuebingen, Germany. Among the 6 predictors identified, the most influential variable for first year growth response was the natural log (ln) of the weekly GH dose. The first year growth response was also correlated with age and distance between height and target height (SD score; both negative) and body weight SD, number of GH injections per week, and oxandrolone treatment given additionally (positive). The first year model explains 46% of the variability, with 1 SD of 1.26 cm. For the second to fourth years, 5 predictors were identified: height velocity during previous years, weekly GH dose (ln), weight SD, oxandrolone therapy (all positive), and age (negative). These models explained 32%, 29%, and 30% of the variability, respectively, with SD scores of 1.1, 1.0, and 1.0 cm, respectively. When the models were applied to the other cohorts, no significant difference was noted between observed and predicted responses. Although the parameters used in our models do not entirely explain the variability in the growth response in Turner syndrome, the parameters themselves were clinically relevant to our present understanding and proved to be of high precision. Some of the tested markers, such as karyotype, do not contribute to the growth response. These variables make the models practical and suitable for planning beneficial and cost-effective therapy.

Anabolic Agents↗
PubMed2005

Cross-cultural adaptation of the VISA-A questionnaire, an index of clinical severity for patients with Achilles tendinopathy, with reliability, validity and structure evaluations.

BACKGROUND: Achilles tendinopathy is considered to be one of the most common overuse injuries in elite and recreational athletes and the recommended treatment varies. One factor that has been stressed in the literature is the lack of standardized outcome measures that can be used in all countries. One such standardized outcome measure is the Victorian Institute of Sports Assessment - Achilles (VISA-A) questionnaire, which is designed to evaluate the clinical severity for patients with Achilles tendinopathy. The purpose of this study was to cross-culturally adapt the VISA-A questionnaire to Swedish, and to perform reliability, validity and structure evaluations. METHODS: Cross-cultural adaptation was performed in several steps including translations, synthesis of translations, back translations, expert committee review and pre-testing. The final Swedish version, the VISA-A Swedish version (VISA-A-S) was tested for reliability on healthy individuals (n = 15), and patients (n = 22). Tests for internal consistency, validity and structure were performed on 51 patients. RESULTS: The VISA-A-S had good reliability for patients (r = 0.89, ICC = 0.89) and healthy individuals (r = 0.89-0.99, ICC = 0.88-0.99). The internal consistency was 0.77 (Cronbach's alpha). The mean [95% confidence interval] VISA-A-S score in the 51 patients (50 [44-56]) was significantly lower than in the healthy individuals (96 [94-99]). The VISA-A-S score correlated significantly (Spearman's r = -0.68) with another tendon grading system. Criterion validity was considered good when comparing the scores of the Swedish version with the English version in both healthy individuals and patients. The factor analysis gave the factors pain/symptoms and physical activity CONCLUSION: The VISA-A-S questionnaire is a reliable and valid instrument and comparable to the original version. It measures two factors: pain/symptoms and physical activity, and can be used in both research and the clinical setting.

Achilles Tendon↗
PubMed2003

Measuring behaviours and perceptions: Rasch analysis as a tool for rehabilitation research.

Variables present in an individual, for example, independence, pain, balance, fatigue, depression and knowledge, cannot be measured directly (hence the term "latent" variables). They are usually assessed by measuring related behaviours, defined by sets of standardized items. The homogeneity of the different items, and proportionality of raw counts to measure, can only be postulated. In 1960 Georg Rasch proposed a statistical model that complied with the fundamental assumptions made in measurements in physical sciences. It allowed for the transformation of the cumulative raw scores (achieved by a subject across items, or by an item across subjects) into linear continuous measures of ability (for subjects) and difficulty (for items). These 2 parameters, only, govern the probability that "pass" rather than "fail" occurs. The discrepancies between model-expected scores (continuous between 0 and 1) and observed scores (discrete, either 0 or 1) provide indexes of inconsistency of individual subjects, items and classes of subjects. In subsequent years the same principles were extended to rating scales, with items graded on more than 2 levels, and to "many-facet" contexts where, beyond items and subjects, multiple raters, times of administration, etc. converge in determining the observed scores. Rasch modelling has increasing application in rehabilitation medicine. New scales with unprecedented metric validity (including internal consistency and reliability) can be built. Existing scales can be improved or rejected on a sound theoretical basis. In clinical trials the consistency and the linearity of measures of either subjects or raters can be validly matched with those of physical and chemical measures. The stability of the item difficulties across time, cultures, diagnostic groups and time of administration can be estimated, thus making it possible to compare homogeneous measures or foster diagnostic procedures on the reasons for differential item functioning.

Activities of Daily Living↗
PubMed2006

A decision aid for GPs for the treatment of elderly male patients with lower urinary tract symptoms (LUTS).

BACKGROUND: GPs have four main treatment options for lower urinary tract symptoms (LUTS): watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors or (referral for) surgery. Guidelines do not provide clear cut-off values for (combinations of) symptoms and physical examination results to decide which treatment is best. OBJECTIVE: (i) To develop a decision aid ('checklist') for GPs for the treatment of patients with LUTS. (ii) To assess its value for use in a primary care population. Materials and methods. Population-based cross-sectional study. Included were subjects with uncomplicated LUTS for whom treatment in primary care may be appropriate. [International Prostate Symptom Score (IPSS) > or = 8, no prior prostate surgery, prostate-specific antigen (PSA) value < 10 ng/ml]. For each subject the appropriateness of surgery and alpha-blocker treatment was determined using a previously validated formalized international expert panel judgement. Regression models using data available in primary care were constructed to predict the panel judgement. Subsequently these models were transformed into simple checklists. Finally, the efficiency of these checklists was calculated. RESULTS: The best checklists consisted of age, symptoms severity, type of symptoms, a quality of life score and PSA value. Assuming one would like to provide at least 95% of the subjects for whom a certain treatment is appropriate with this treatment (i.e. 'sensitivity' of the checklist > or = 95%), one can reach a positive predictive value of 50-60%. CONCLUSION: Simple checklists based on the judgement of experts regarding the most appropriate therapy can help GPs to advise their patients of a rational treatment strategy.

Adrenergic alpha-Antagonists↗
PubMed2002

The measurement of engagement in the homeless mentally ill: the Homeless Engagement and Acceptance Scale--HEAS.

BACKGROUND: Much of the difficulty in helping the homeless mentally ill arises as a consequence of their resistance to engagement. A refused intervention can seldom influence a client's problems and engagement status can be argued as being an important independent predictor of outcome. No instrument could be identified which systematically measured the factors involved. This paper describes the development and psychometric properties of a new scale, the Homeless Engagement and Acceptance Scale (HEAS). METHOD: Staff from an established project for the homeless mentally ill helped to identify relevant questions used to develop a five-item rating scale for completion by an informant. After piloting, the instrument was tested in a study in which subjects were assessed twice over 12 months by informants. Item analysis was undertaken and predictive validity was assessed. RESULTS: Item analysis indicated a good facility index signifying all items were able to differentiate subjects according to the characteristic being measured, and a high discrimination index demonstrating that all items were measuring the same concept. Predictive validity and internal consistency coefficients were both good. The 3 month HEAS score was found to be a significant predictor of accommodation status and adequacy of a support network at 12 months. CONCLUSIONS: The good psychometric properties and predictive validity of the scale suggest the HEAS is likely to be a useful tool in assessing engagement status. One of the five questions (Q4) can be omitted for those who are not homeless and the scale termed the Engagement and Acceptance Scale (EAS).

Defense Mechanisms↗
PubMed2002

The reliability of the Low Back Outcome Score for back pain.

STUDY DESIGN: A prospective test-retest study was conducted to investigate both new and follow-up patients with low back pain presenting to an orthopedic surgeon specializing in back pain. OBJECTIVES: To further validate the internal consistency and test-retest reliability of the Low Back Outcome Score, and to compare these results with other condition-specific disability scales. SUMMARY OF BACKGROUND DATA: To be useful in clinical practice, health-specific questionnaires must demonstrate reliability and validity. Several disease-specific questionnaires for low back pain have been validated to different extents. METHODS: In this study, 102 new and 42 follow-up patients consecutively attending a consultant clinic completed the Low Back Outcome Score on their visit, then again after an interval of 1 week in postal form. This instrument also was completed by 230 patients presenting to a physiotherapist. RESULTS: A response rate of 90% was achieved for the postal questionnaire. A test of internal consistency conducted with the study sample achieved a Cronbach alpha coefficient of 0.85. Overall agreement for test-retest reliability was 84%, and the reliability coefficient (K) reached a range of 0.51 to 0.86 (P < 0.05). A Bland/Altman plot was calculated, demonstrating that only 5% of patient scores change by more than 11.6 scale points between test and retest, which is not sufficient to change outcome categories. CONCLUSION: The Low Back Outcome Score appears to have good internal consistency and test-retest reliability for use in clinical practice.

Adult↗
PubMed1999

Development of the Quality of Life in Epilepsy Inventory for Adolescents: the QOLIE-AD-48.

PURPOSE: We report the development of an instrument to assess health-related quality of life (HRQOL) in adolescents with epilepsy. METHODS: A sample of 197 English-speaking adolescents (aged 11-17 years) with epilepsy completed a test questionnaire of 88 items. Also included were mastery and self-esteem scales to assess external validity. A parent simultaneously completed an 11-item questionnaire to evaluate the child's HRQOL. Both adolescent and parent questionnaires were repeated in 2-4 weeks. Demographic information and information pertaining to seizures were collected at baseline along with assessment of systemic and neurologic toxicity. RESULTS: The QOLIE-AD-48 contains 48 items in eight subscales: epilepsy impact (12 items), memory/concentration (10), attitudes toward epilepsy (four), physical functioning (five), stigma (six), social support (four), school behavior (four), health perceptions (three), and a total summary score, with higher scores indicating better HRQOL. Internal construct validity was demonstrated in a single-factor solution for the eight dimensions. All correlations were statistically significant at p < 0.05 level. Internal consistency reliability estimated by Cronbach's alpha coefficient was 0.74 for the summary score and ranged from a low of 0.52 (three-item Health Perceptions Scale) to 0.73-0.94 for the other individual scales. Good test-retest reliability was found for the overall measure (0.83). Summary score correlations with the two external validity scales, self-efficacy and self-esteem were 0.65 and 0.54, respectively. Statistically significant differences in summary scores indicating that HRQOL was increasingly better for adolescents as seizure severity decreases (no seizures = 77+/-13, low = 70+/-17, high = 63+/-17) were found among seizure-severity groups. CONCLUSIONS: These data describe the development of a robust instrument to evaluate HRQOL in adolescents with epilepsy. Empiric analyses provide strong evidence that the QOLIE-AD-48 is both a reliable and valid measure for adolescents with epilepsy.

Adolescent↗
PubMed1997

Development and validation of the diabetes fear of injecting and self-testing questionnaire (D-FISQ): first findings.

To quantify the degree of fear of self-injecting insulin and self-testing of blood glucose in adult insulin-treated diabetic patients, the Diabetes Fear of Injecting and Self-testing Questionnaire (D-FISQ) was developed. The D-FISQ is a 30-item self-report questionnaire consisting of two subscales that measure Fear of Self-Injecting (FSI) and Fear of Self-Testing (FST). To test validity and internal consistency, the D-FISQ was administered to a sample of 266 insulin-treated patients (Type 1 and Type 2); four diagnosed injection phobic insulin-requiring diabetic patients also completed the D-FISQ. The minimal score was obtained on the subscales by 62% (FSI) and 57% (FST) of the population. The D-FISQ demonstrated high internal consistency, with Cronbach's as of 0.94 (D-FISQ), 0.94 (FSI), and 0.90 (FST). Spearman rho between fear of self-injecting and fear of self-testing was 0.59 (p < 0.001), justifying two separate subscales. Construct validity was confirmed by a correlation of 0.44 with Spielbergers Trait Anxiety Inventory (Spearman rho, p < 0.001). FSI-scores from the injection phobic patients were all > or =95th percentile, while three scored > or =95% on FST, indicating discriminative validity. Results confirm homogeneity and validity of the D-FISQ and suggest usefulness of this instrument in both clinical practice and research.

Adult↗
PubMed2003

[Translation and validation of an instrument for evaluation of severity of symptoms and the functional status in carpal tunnel syndrome].

The objective of the present study was to translate, to do cultural equivalence and validation of the Levine et al. (1993) or Boston Carpal Tunnel Questionnaire (BCTQ) to Portuguese. The BCTQ application to patients, selected by the question "What was the reason that brought you to look for a physician and that led him to ask this examination?" showed very good reproducibility. The validity was measured through the comparison of the severity symptoms scores (SSS) and the functional status scores (FSS) with the results of grip forces, Minnesota, two point discrimination, Semmes-Weinstein filaments perception and sensory conduction at the median nerve. The internal consistency was evaluated through Chronbach's alpha coefficient comparing the SSS and the FSS. The measuring properties were evaluated through paired t-test between pre and pos-surgical scores. Reproducibility, internal consistency, validation and measuring properties of the translated BCTQ were similar to those found by Levine et al. with the original version.

Carpal Tunnel Syndrome↗
PubMed2004

Developing and evaluating an oral health-related quality of life index for children; the CHILD-OIDP.

OBJECTIVE: To develop an oral health-related quality of life index in Thai children and evaluate its psychometric properties. DESIGN: Cross-sectional study of children aged 11-12 years, attending the final year of primary school (grade-six). Development and evaluation process was conducted on non-random sample in U-thong District, Suphan-buri province, Thailand. Re-evaluation of the index included all target group children in a municipal area of Suphan-buri province, Thailand. The psychometric properites evaluated in this study refer to face, content and concurrent validity and internal and test-retest reliability. PARTICIPANTS: 513 children in the development process. 1,100 children in the re-evaluation. RESULTS: Throughout the development process, the OIDP index was modified and its psychometric properties evaluated. The final test revealed excellent validity and reliability. Weighted kappa was 0.93. There was no negative correlation between any item, corrected item-total correlation coefficients were between 0.4-0.7, Standardised Cronbach's alpha coefficient was 0.82. The index showed very significant associations with perceived oral treatment need (p < 0.001) and perceived oral health problems (p < 0.001). The validity and reliability of the index was confirmed by similar results in the re-evaluation study. CONCLUSIONS: This study has demonstated that the CHILD-OIDP index is a valid, reliable and practical measure of oral health-related quality of life in 12 year old Thai children.

Child↗
PubMed1998

Reliability and validity of the interview and self-report versions of the BASIS-32.

The psychometric properties of the interview and self-report versions of the BASIS-32 were compared. A total of 120 severely mentally ill adults enrolled in psychosocial rehabilitation were randomly assigned to either a self-report or an interview condition. The BASIS-32 had good internal consistency and test-retest reliability on most subscales; coefficients were higher in the self-report condition. Only the interview version of the psychosis subscale had unacceptable internal consistency. Validity correlations were generally good for the symptom subscales but disappointing for the functional domains. The subscale scores did not discriminate between diagnostic subgroups.

Adult↗