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PubMedDate not supplied

Evaluation of the Chinese version of the Disability of the Arm, Shoulder and Hand (DASH-HKPWH): cross-cultural adaptation process, internal consistency and reliability study.

UNLABELLED: The Disability of the Arm, Shoulder and Hand (DASH) was translated into Chinese by a physiotherapy team of the Prince of Wales Hospital, Hong Kong (DASH-HKPWH). OBJECTIVES: This study evaluated the cross-cultural adaptation process, face validity, internal consistency and reliability of the DASH-HKPWH. METHOD: Language officers and medical professionals from different fields were invited to translate and evaluate the face validity of the DASH-HKPWH. 88 patients were recruited to complete two DASH questionnaires on two occasions 1-2 weeks apart. RESULTS: Some adjustments were made to the translations based on the cultural and linguistic practice in Hong Kong. The face validity was satisfactory with a mean endorsement score of 3.2. The difference between the mean of DASH scores was not significant (t = -0.35, p = 0.73). The ICC (1,1) and Cronbach's alpha for the 30-item Disability/Symptom of the DASH-HKPWH was 0.77 and 0.94, respectively. CONCLUSION: The translation was valid and reliable and acceptably equivalent to the original version. The questionnaire is suitable for measuring changes experienced by patients with any upper extremity disorders.

Activities of Daily Living↗

PubMed1999

Generic and condition-specific outcome measures for people with osteoarthritis of the knee.

OBJECTIVES: The aims of this study were to evaluate two condition-specific and two generic health status questionnaires for measuring health-related quality of life in patients with osteoarthritis (OA) of the knee, and to offer guidance to clinicians and researchers in choosing between them. METHODS: Patients were recruited from two settings: 118 from knee surgery waiting lists and 112 from rheumatology clinics. Four self-completion questionnaires [Western Ontario and McMaster University Osteoarthritis Index (WOMAC), Health Assessment Questionnaire (HAQ), Short Form-36 (SF-36) and Euroqol] were sent to subjects on two occasions 6 months apart. Construct validity, convergent validity, internal consistency and responsiveness were examined using primarily non-parametric methods. RESULTS: All instruments proved satisfactory in terms of ease of use, acceptability to patients, internal consistency and reliability. In the surgical group, the OA-specific WOMAC performed better than the HAQ and the generic measures in terms of validity and responsiveness to change, whereas in the rheumatology group the SF-36 was more responsive. CONCLUSION: WOMAC is the instrument of choice for evaluating the outcome of knee replacement surgery in OA. The SF-36 provides a more general insight into patients' health and may be more responsive to change than the WOMAC in a heterogeneous rheumatology clinic population. Researchers wishing to undertake an economic evaluation might consider the EQ-5D for a surgical, but not a rheumatology clinic group.

Aged↗

PubMed1984

Practicable and valid approach to evaluate the efficacy of nootropic drugs by means of rating scales.

Starting with the disputable practice of evaluating the efficacy of nootropic drugs the author has developed a strictly experimental examination approach emphasising the internal validity of experiments. The physician's assessment of the global therapeutic effect is suggested as a variable examination factor which should be treated as an independent variable and a valid instrument for judging the effect when arriving at a statistical conclusion. Differentiated rating scales and measurements are suggested as a basis for this judgment. Proven effects are described in a more differentiated manner by means of this method which helps in discussing the validity of results.

Aged↗

PubMedDate not supplied

Age-based construct validation using structural equation modeling.

In this paper we describe some mathematical and statistical models based on structural equation modeling (SEM) using computer programs like LISREL. We focus on SEM methodology for the simultaneous examination of the internal validity of psychological constructs and the external validity represented by age relations. To illustrate these ideas we use a latent variable path model to examine the organization of intellectual abilities measured by the WAIS-R in the standardization sample. We also examine different ways in which age can be used to structure this organization. This is primarily a methodological paper, but we try to integrate conceptual principles of modeling with some substantive issues of research on the psychology of aging.

Aging↗

PubMed1995

Self selection and sample selection in a treatment study of social phobia.

The external validity or generalizability of a treatment outcome study may be influenced by the choices patients make (self-selection) and by study requirements intended to increase internal validity or protect subject welfare (e.g. sample selection). Although these effects are well-known, they have rarely been studied, and little is known about the impact they may have on generalizability of findings. In this study, subjects accepting random assignment to a larger study examining pharmacologic and cognitive-behavioral treatments for social phobia were compared with subjects refusing random assignment (i.e. self-selected) and excluded subjects (i.e. "sample-selected"). "Acceptors" differed from "refusers" on some measures suggesting that they have a lower annual income and may have fewer social supports. Therefore, they may have fewer available resources and might be more willing to accept help wherever it is offered. Despite these differences, acceptors differed from refusers on just one pretreatment measure of clinical functioning. Excluded subjects did not differ from refusers or acceptors on demographic or pretreatment clinical measures. Refusers and excluded subjects were treated with the same cognitive-behavioral treatment used in the comparative outcome study, and their posttreatment data were compared with the subgroup of acceptors who were randomly assigned to that treatment. Again, there were few significant differences. These results suggest that while self-selection and sample selection may have influenced some characteristics of the sample in this comparative outcome study, the three groups of subjects were clinically similar and responded similarly to cognitive-behavioral treatment of social phobia.

Adult↗

PubMed2004

A brief diagnostic screening instrument for mental disturbances in general medical wards.

OBJECTIVE: Mental illness is prevalent among general hospital ward patients but often goes unrecognised. The aim of this study was to validate the SCL-8d as a brief questionnaire for mental disturbances for use in general hospitals. METHODS: The study included 2040 patients, 18 years or older, consecutively admitted to 11 general internal medicine wards in seven European countries. All patients were screened on admission by means of the SCL-8d questionnaire. The psychometric performance (i.e., the internal validity) of the SCL-8d scale was tested using modern item response theory (IRT) in the form of the Rasch model. RESULTS: Differences between sample characteristics were considerable. Even so, the SCL-8d scale showed a remarkable, statistically significant fit in terms of internal homogeneity (P>.01) in all individual settings, except in Spain and Germany where the item "Everything is an effort" had to be excluded to obtain a fit. When pooling data from all centres, an excellent statistical significance of fit (P>.05) was obtained by exclusion of the "Effort" item. The scale was homogeneous as to gender (P>.05), but not age as it performed better among young patients than among patients older than 60 years (P<.01). In these two patient groups both internal and external homogeneity (gender, median age) was achieved. The SCL-8d sum score showed a marked correlation with current and previous treatment for mental illness. CONCLUSION: Apart from the "Effort" item ranking differently on the latent severity dimension as to age, the SCL-8d seems very robust from a psychometric point of view. Besides being short, the SCL-8d scale contains only emotional symptoms. It would therefore seem to be an excellent diagnostic tool for use in medical settings.

Adolescent↗

PubMed1998

Measuring outcome after liver transplantation: a critical review.

As the number of liver transplantations performed around the world and the survival rates increase, attention is turning to the broad impact this procedure has on patients' quality of life (QOL), including their physical and psychosocial functioning and their perceived sense of well-being. There exists a small body of literature that examines the global effects of liver transplantation on QOL. The purpose of this article is to discuss the general framework used to assess QOL and to critically review the studies that have broadly examined QOL outcomes after liver transplantation. The reviewed studies used measures that led to broad assessment of the various domains of QOL. Although the instruments used to measure QOL in these studies are largely validated, there is significant heterogeneity in this literature in terms of the instruments used, leading to difficulties in making generalizable conclusions among the studies. Although limited by internal validity problems, the available data suggest improvement in QOL by liver transplantation. Additionally, a large recent study that used the Liver Transplant Database Quality of Life Questionnaire also reported a subset of patients in whom QOL seemed to worsen after liver transplantation. Knowledge of the factors related to QOL outcome after liver transplantation is important because it might allow development of new interventions that may have an impact on future allocation decisions.

Humans↗

PubMed2004

Identifying patients at risk of intraoperative and postoperative transfusion in isolated CABG: toward selective conservation strategies.

BACKGROUND: Allogeneic blood product use during cardiac operation is often reported to exceed 40% despite published guidelines and costly blood conservation strategies. We developed a predictive model, based on eight preoperative risk factors, of allogeneic blood product transfusion rates in patients undergoing a cardiac procedure. METHODS: All 3,046 consecutive, isolated coronary artery bypass graft (CABG) procedures at a university hospital from 1995 to 1998 were included. A logistic regression model was created to identify independent predictors of allogeneic blood product transfusion. This model was validated using a prospective patient sample. RESULTS: Overall use of allogeneic blood products was 23% with a crude operative mortality of 2.1%. In isolated, elective, first-time CABG cases, 16.9% received allogeneic blood products. Independent predictors of blood product usage in CABG patients were preoperative hemoglobin 12.0 or less, emergent operation, renal failure, female sex, age 70 years or older, left ventricular ejection fraction 0.40 or less, redo procedure, and low body surface area. Prospective validation of this model on 2,117 consecutive isolated CABG patients demonstrated an observed-to-expected allogeneic blood product transfusion rate ratio of 1.06. CONCLUSIONS: This internally validated logistic regression risk model is a sensitive and specific predictor of allogeneic blood product use in patients undergoing isolated CABG. Utilization of this model allows for preoperative risk stratification and may allow for more rational resource allocation of costly blood conservation strategies and blood bank resources.

Adult↗

PubMed2003

Mortality in Emergency Department Sepsis (MEDS) score: a prospectively derived and validated clinical prediction rule.

OBJECTIVES: Our objectives were a) to identify univariate correlates of death in emergency department patients at risk for infection; b) to perform multivariate analyses and identify independent predictors of death; and c) to develop and internally validate a prediction rule that may be used in the emergency department to risk stratify patients into different risk groups to predict their mortality rate. DESIGN: Prospective cohort study. SETTING: Emergency department of an urban university referral center. PATIENTS: Consecutive emergency department patients, aged 18 or older, who were at risk for infection, as indicated by the emergency department physician ordering a blood culture between February 1, 2000, and February 1, 2001. Of 3,301 eligible patient visits, 3,179 (96%) were enrolled. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was 28-day in-hospital mortality rate. There were 2,070 visits in the derivation set, with 110 deaths (5.3%), and 1,109 visits in the validation set, with 63 deaths (5.7%). Independent multivariate predictors of death were terminal illness (odds ratio, 6.1; 95% confidence interval, 3.6-10.2), tachypnea or hypoxia (2.7, 1.6-4.3), septic shock (2.7, 1.2-5.7), platelet count <150,000 (2.5, 1.5-4.3), band proportion >5% (2.3, 1.5-3.5), age >65 (2.2, 1.3-3.6), lower respiratory infection (1.9, 1.2-3.0), nursing home residence (1.9, 1.2-3.0), and altered mental status (1.6, 1.0-2.6). The clinical prediction rule stratified patients into mortality risk groups of very low, 0.9% (95% confidence interval, 0.2-1.5%); low, 2.0% (0.8-3.2%); moderate, 7.8% (5.6-10%); high, 20% (13-27%); and very high, 50% (36.1-64%) in the derivation set. Mortality rates for the corresponding risk groups in the validation set were 1.1%, 4.4%, 9.3%, 16%, and 39%, respectively. The receiver operating characteristic area for the rule was 0.82 in the derivation set and 0.78 in the validation set. CONCLUSIONS: In patients with suspected infection, this model identifies significant correlates of death and allows stratification of patients according to mortality risk. As new therapies become available for patients with sepsis syndromes, the ability to predict mortality risk may be helpful in triage and treatment decisions.

Age Distribution↗

PubMed2001

Reliability and validity of the International Prostate Symptom Score in a Malaysian population.

OBJECTIVE: To validate the English version of the International Prostate Symptom Score (IPSS) in patients with and without urinary symptoms in a Malaysian population. PATIENTS AND METHODS: Validity and reliability were assessed in patients with lower urinary tract symptoms (LUTS) and in patients with no LUTS. Reliability was evaluated using the test-retest method and internal consistency using Cronbach's alpha. Sensitivity to change was expressed as the effect size in the score before and after intervention in additional patients with LUTS who underwent transurethral resection of the prostate (TURP). RESULTS: Internal consistency was excellent; there was a high degree of internal consistency for each of the seven domains and for the total score (Cronbach's alpha > or = 0.60 and > or = 0.79, respectively) in the populations studied. The test-retest correlation coefficient for the seven domain scores was highly significant. The intra-class correlation coefficient was high (> or = 0.59). There was a high level of sensitivity and specificity for the effects of treatment, with a very significant change between the seven scores domains in the treated group but not in the control group. CONCLUSIONS: The IPSS is suitable, reliable, valid and sensitive to clinical change in the Malaysian population.

Aged↗

PubMed2005

Development and validation of the effectiveness of [corrected] auditory rehabilitation scale.

OBJECTIVE: To develop a new scale of hearing-related function and quality of life in patients with hearing aids that addresses overlooked concerns, such as hearing-aid comfort, convenience, and cosmetic appearance, that may influence hearing-aid adherence while maintaining brevity and sensitivity to clinical change. DESIGN: Prospective, multicenter instrument validation. SETTING: Four diverse sites in Washington State, including 2 private practices, 1 university setting, and 1 Veterans Affairs hospital. PATIENTS: Seventy-eight patients with hearing aids. INTERVENTIONS: We created 2 modules in the Effectiveness of Auditory Rehabilitation (EAR) scale. The first module (Inner EAR) covers intrinsic hearing issues such as hearing in quiet and hearing in noise and is administered both before and after treatment. The second module (Outer EAR) covers extrinsic (hearing-aid related) issues such as comfort, appearance, and convenience and is administered after hearing-aid fitting. MAIN OUTCOME MEASURES: Both scales were developed and validated in 3 stages. Stage 1 used a qualitative approach from multiple data sources to develop preliminary instruments. Stage 2 used approaches from classic test theory to reduce the number of items and psychometrically validate the instruments. Stage 3 examined the responsiveness or sensitivity to clinical change. RESULTS: A 10-item Inner EAR module and a 10-item Outer EAR module were created and validated. Internal consistency of individual domains (Cronbach alpha = 0.85 and 0.72, respectively) and test-retest reliability (intraclass correlation coefficients = 0.76 and 0.81, respectively) were excellent. Evidence of construct validity included concurrent validity with other hearing scales and global visual analog scales, discriminant validity with dizziness handicap, correlation with hearing-aid adherence, and confirmatory factor analyses. Both scales had strong evidence of responsiveness (sensitivity to change), with higher effect sizes and Guyatt responsiveness statistics than the 2 widely used hearing scales in this study. The scales took an average of 5 minutes to complete. CONCLUSIONS: The EAR scale is a valid and reliable measure of the effectiveness of amplification in the treatment of sensorineural hearing loss. It addresses the range of issues that are of importance to hearing-aid patients. The scales have excellent psychometric properties, are more responsive than several widely used hearing scales, and are minimally burdensome for patients to complete. The EAR may be a valuable outcome measure in future studies of both existing hearing aids and newer hearing-aid technologies, such as bone-anchored aids or middle ear implants.

Factor Analysis, Statistical↗

PubMed2002

[The Spanish version of Skindex-29. An instrument for measuring quality of life in patients with cutaneous diseases].

BACKGROUND: Quality-of-life studies aim to measure objectively how patient life is affected by disease. Generation of a novel instrument is more expensive and time-consuming than adapting a test already existing in another language. Skindex-29 is a widely validated American instrument to measure quality of life in patients with cutaneous disease. A study of the psychometric properties of the Spanish version of Skindex-29 is presented. PATIENTS AND METHOD: The test was administered to adults in an outpatient dermatological clinic. Age, sex and disease were registered for each patient. Three groups were studied: healthy people, patients with inflammatory skin disease and patients with isolated or tumoral lesions. Construct validity, internal consistency, reproducibility at 72 hours, responsiveness and feasibility were evaluated. RESULTS: Responses of 318 patients were analyzed; 65% were women, with a mean age of 36 years. Validity construction was demonstrated, with significant differences between healthy people and patients as well as between both groups of patients. Reliability was also demonstrated, with Cronbach's coefficient alpha values above 0.84 and intraclass correlation values above 0.7. The test showed responsiveness to clinical change. The percentage of non-response was low, and floor and ceiling effects were adequate. CONCLUSION: The Spanish version of Skindex-29 constitutes an instrument with validity, reliability, and sensitivity to change to measure the effects of cutaneous conditions on quality of life of Spanish patients.

Adult↗

PubMed2004

[The problem of response in epidemiological studies in Germany (part I)].

To achieve high response rates in German epidemiological studies is growing more difficult. Low response in epidemiological studies may decrease the acceptance of the results. Response, however, is not identical with the quality of a study. In the first part of this paper various definitions of response (contact, cooperation, response, recruitment proportions) are introduced and discussed in the context of different study designs with reference to practical examples. A population-based survey such as the Study of Health in Pomerania (SHIP) investigates the distribution of risk factors and health-related endpoints. Surveys should yield representative results which can be generalised to apply to the entire population (external validity). This study design usually requires large participitation proportions. In a prospective cohort study such as the European Investigation into Cancer and Nutrition (EPIC) the emphasis is on internal validity. A stable study population willing to participate in regular follow-ups is a primary recruitment goal. If the response in a case-control study such as the Northern Germany Leukaemia and Lymphoma Study (NLL) is low, the priority is to achieve approximately equal response proportions for cases and controls. Simultaneous public relation and media activities can improve participitation in a study. Multidimensional strategies combining public communications, cooperation with local and regional officials and frequent press and media coverage are emphasised. The second part of this paper will discuss methods to quantify the effects of the response proportions on the validity of the study results.

Adult↗

PubMed2004

Age-related macular degeneration and quality of life: how to interpret a research paper in health-related quality of life.

PURPOSE OF REVIEW: To review how to critically appraise a research article pertaining to changes in health-related quality of life (HRQoL) related to interventions for age-related macular degeneration (AMD). RECENT FINDINGS: We searched PubMed using a strategy that combined the text-words, "macular degeneration" and "quality of life" (n = 73; January 17, 2004), while limiting the search to "clinical trials" (n = 6; of which 3 were published within the past year). A randomized clinical trial evaluating the efficacy of self-management as an intervention for AMD has been selected to introduce the reader to the concept of how to critically review a research paper pertaining to HRQoL in AMD. Other pertinent articles used in this review include recent results published from the Age-Related Eye Disease Study and the Submacular Surgery Trial. SUMMARY: The NEI-VFQ is a reliable, valid, and responsive tool when applied to patients with AMD. Self-management of patients with AMD has been demonstrated to improve their HRQoL by way of an internally valid randomized clinical trial. In this issue of Current Opinion in Ophthalmology, we confront the issue of how to assess the validity and importance of a research paper pertaining to the issue of quality of life. To introduce this topic, we will present a real world clinical example to better understand how quality of life may aid in medical decision making.

Clinical Trials as Topic↗

PubMed2002

Reliability and validity of Endotower, a virtual reality trainer for angled endoscope navigation.

We hypothesized that a simulator designed to train surgical novices angled laparoscopic navigation would show an improvement in subjects' performance, a high test re-test reliability and high internal validity as measured by standardized coefficient alpha. It was also predicted that simulator performance would be strongly related to objectively assess perceptual and visuospatial ability. EndoTower has good face validity in that it mimics precisely the performance of an angled laparoscope and previous studies suggest construct validity. In this study, EndoTower is shown to be a trainer intended for laparoscopic skill than can test for inherent perceptual and visuospatial ability.

Computer Simulation↗

PubMed2006

[Internal consistency and reliability of Primary Care Assessment Tool (PCATool-Brasil) for child health services].

Health strategies based on primary health care have been expanding in Brazil. An instrument applied to users, the Primary Care Assessment Tool (the PCATool), which measures the extent of primary care, has been validated in the United States. We sought to adapt the PCATool to Brazil and analyze its validation and reliability through a cross-sectional validation study of the Child PCATool. Validation included: translation, back-translation, adaptation, debriefing, content and construct validate, internal consistency, and reliability analysis. The questionnaire was applied to 468 parents or guardians of children registered with 18 primary health services in Porto Alegre, representing the services' normal pediatric population. Using factor analysis, 8 domains were identified, with Cronbach's aranging from 0.74 to 0.88. Validation resulted in a 45-item scale, divided into 8 attributes (Access to First Contact, Continuity, Coordination, 3 attributes of Comprehensiveness, Community Orientation, and Family Orientation). These results showed that the PCATool-Brasil has adequate validity and reliability and could be used as a national instrument to evaluate primary health care after its application to other population settings in the country.

Brazil↗

PubMed2000

Development of a health-related quality of life questionnaire for women with androgenetic alopecia.

Despite the negative effects of androgenetic alopecia (AGA), no standardized health-related quality of life (HRQOL) questionnaire which is both specific to women and suitable for use in clinical trials currently exists. A questionnaire to assess HRQOL in women with AGA, the Women's Androgenetic Alopecia Quality of Life Questionnaire (WAA-QOL), was recently developed. Aspects of life affected by AGA were generated from literature review, discussion with experts, and a focus group. The number of issues identified was reduced based on importance and relevance to women with AGA. A questionnaire was then constructed and pilot-tested for comprehension. The resulting 25-item instrument was later included in a double-blind, placebo-controlled clinical trial of finasteride 1 mg for the treatment of hair thinning in postmenopausal women (n = 137). Based on test characteristics, several questions were eliminated, resulting in a 16-item questionnaire. The WAA-QOL exhibited excellent test-retest reliability overall (intraclass correlation coefficient = 0.89), and for individual items (kappa = 0.66-0.85), as well as high internal consistency (Crohnbach's alpha = 0.98). Responsiveness of the questionnaire could not be assessed. The WAA-QOL is self-completed in about 10 min, exhibits good content validity, internal consistency, and test-retest reliability, and may be useful in assessing the impact of female AGA on HRQOL or in evaluating therapeutic effects in clinical trials.

Adult↗

PubMed2004

Development of a measure to delineate the clinical trials nursing role.

PURPOSE/OBJECTIVES: To identify the significant dimensions of the clinical trials nursing role and to construct a reliable and valid survey instrument to reflect these dimensions. DESIGN: Methodologic survey. SETTING/SAMPLE: The judge panel consisted of six national nurse experts. The focus group sample was comprised of 24 clinical research nurses from the West, Northeast, and Great Lakes regions of the United States and five research nurses from Canada. The sample for instrument testing consisted of 40 oncology clinical research nurses from the Southeast. METHODS: Several strategies were used to develop the Clinical Trials Nursing Questionnaire (CTNQ): literature review, conceptualization of the subscales, development of items for each subscale, development of the tool, expert judge panel evaluation, focus group testing, administration of the tool, and psychometric analysis of the results. MAIN RESEARCH VARIABLES: Frequency and importance of clinical trials nursing activities. FINDINGS: Content validity was established at 0.95. The alpha reliability coefficient was 0.92 for the frequency scale and 0.95 for the importance scale. A two-week test-retest reliability of 0.88 was obtained for the frequency scale and 0.92 for the importance scale. The final CTNQ contained 12 sections with 154 items. CONCLUSIONS: The CTNQ has acceptable content validity, internal consistency, and stability reliability. This instrument is promising for the assessment of the research nurse role, and its use in further research is appropriate. IMPLICATIONS FOR NURSING: A valid and reliable measure can be used to delineate the subspecialty of clinical trials nursing, thus providing a better understanding of how nursing professionals contribute to the cancer research enterprise.

Clinical Trials as Topic↗