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At least 145 records · Page 8Linked to original sources
PubMed2000

Validation of the gastrointestinal quality of life index for patients with potentially operable periampullary carcinoma.

BACKGROUND: A disease-specific quality of life questionnaire is not available for patients with periampullary carcinoma, although cancer-specific questionnaires and the Gastrointestinal Quality of Life Index (GIQLI) have been used. The aim of this study was to validate the GIQLI for patients with periampullary tumours and to evaluate if subscales of the GIQLI could be identified to allow a more detailed assessment of the patients' quality of life. METHODS: Patients with periampullary carcinoma, included in a study concerning diagnostic laparoscopy, were asked about symptoms and completed a questionnaire comprising the Medical Outcomes Study (MOS) 24 questionnaire, the GIQLI and one question of the Rotterdam Symptom Check List (RSCL). Clinical interpretation and statistical factor analysis were used to identify subscales of the GIQLI. RESULTS: The GIQLI could be divided into four subscales, measuring physical well-being, mental well-being, digestion and defaecation. All four subscales had a good internal reliability and the construct validity was supported by the pattern of correlations with the MOS and RSCL as well as differences in subscale scores for patients with or without certain symptoms. CONCLUSION: In patients with periampullary tumours the GIQLI can be divided into four subscales, measuring different aspects of quality of life. These subscales provide insight into the different problems affecting the patient.

Adult↗
PubMed1999

Sample size estimation in phase III cancer clinical trials.

This paper deals with the basic principles involved in sample size calculation of phase III cancer clinical trials. It illustrates the concepts and factors determining the sample size. Various examples of phase III cancer clinical trials are provided and the sample size is calculated taking into account the assumptions made. The examples provided include sample sizes for comparing proportions and sample sizes for comparing survival times. Several special topics are also discussed including choice of endpoint, number of treatment groups, factorial designs and equivalence trials.

Clinical Trials, Phase III as Topic↗
PubMed2001

[Development of the Borderline Symptom List].

The categorical diagnosis of borderline personality disorder (BPD) is currently discussed as sufficiently reliable and valid. However, specific standardized instruments to measure the degree of the symptomatology are currently not available. Based on the criteria of DSM-IV, the Diagnostic Interview for Borderlines (DIB-R) and the opinion of clinical experts and borderline-patients, a self-rating scale was developed to quantify the intrapsychic strain of patients with BPD. 308 female borderline-patients scored the 99 items. Factor analyses revealed seven factors: self-image, affect regulation, autoaggression, dysthymia, social isolation, intrusions and hostility. Analyses of reliability and validity revealed promising results.

Adolescent↗
PubMed1998

Evaluation of a Swedish version of the Hearing Disabilities and Handicaps Scale, based on a clinical sample of 101 men with noise-induced hearing loss.

The aim of this study was to evaluate, in terms of descriptive statistics, factor analysis, corrected item-total correlations, and internal consistency reliability, a Swedish translation of the Hearing Disabilities and Handicaps Scale (HDHS). The HDHS is shortened and modified version of the Hearing Measurement Scale. Data from 101 men having noise-induced hearing loss, with the pure-tone audiometric data showing a median value of 53.3 dBHL (R = 81.6; Q = 12.5) over the frequencies 3, 4, and 6 kHz better ear, were assessed at the Department of Audiology, Sahlgrenska University Hospital, Göteborg. A principal component analysis followed by a varimax rotation was conducted giving four emerging factors, accounting for 64.6% of the variance. Two of the factors, "speech perception" (alpha = 0.89) and "non-speech sounds" (alpha = 0.85), appear to measure perceived disability, whereas two factors, "interpersonal distress" (alpha = 0.79) and "threat to self-image" (alpha = 0.84), appear to measure dimensions related to the process of creating a handicap. The four-factor HDHS needs to be further tested in order to find out its usefulness for clinical assessment of perceived disability and handicap.

Adolescent↗
PubMedDate not supplied

Self-reported outcomes of aural rehabilitation in a developing country.

The aim of this study was to evaluate self-reported outcomes among hearing aid users (age 16-89 years; mean 45.8 years) to determine the effectiveness of aural rehabilitation in Nigeria based on the International Outcome Inventory for Hearing Aids (IOI-HA). The responses were evaluated with descriptive statistics, factor analysis of the principal components and multiple regressions. Most respondents reported favorable outcomes in all domains of the inventory, comprising: daily use (mean 4.1; SD 1.2), benefits (mean 3.5; SD 1.1), residual activity limitation (mean 3.4; SD 1.2), satisfaction (mean 3.7; SD 1.2), residual participation restriction (mean 3.5; SD 1.3), impact on others (mean 3.4; SD 1.3) and changes in quality of life (mean 3.8; SD 1.0). The mean score distribution compared favorably with those reported in the developed world. There were significant intercorrelations among all items, and two factors (eigenvalue>1) accounted for 68% of the underlying variance. Impact on others was the only domain associated with demographic/audiologic variables. The study showed that aural rehabilitation is feasible and effective in enhancing activity and participation for the hearing impaired in a developing country.

Adolescent↗
PubMed2000

Clustering of procoagulation, inflammation, and fibrinolysis variables with metabolic factors in insulin resistance syndrome.

The known metabolic cardiovascular disease risk factors associated with insulin resistance syndrome (IRS) do not adequately explain the excess cardiovascular disease risk attributed to this syndrome, and abnormalities in hemostatic variables may contribute to this excess risk. Using data from 322 nondiabetic elderly men and women (aged 65-100 years) participating in the Cardiovascular Health Study during 1989-1990, the authors performed factor analysis on 10 metabolic risk factors associated with IRS and 11 procoagulation, inflammation, and fibrinolysis variables to examine the clustering of the metabolic and hemostatic risk markers. Factor analysis of the metabolic variables confirmed four uncorrelated factors: body mass, insulin/glucose, lipids, and blood pressure. Adding the hemostatic variables yielded three new factors interpreted as inflammation, vitamin K-dependent proteins, and procoagulant activity. Plasminogen activator inhibitor-1 clustered with the body mass factor, supporting the hypothesis that obesity is related to impaired fibrinolysis. Fibrinogen clustered with the inflammation summary factor rather than procoagulant activity, supporting the position that fibrinogen principally reflects underlying inflammation rather than procoagulant potential. The authors conclude that should hemostatic variables be shown to contribute to IRS-related cardiovascular disease, apart from plasminogen activator inhibitor-1, they may do so independently of the established metabolic abnormalities.

Aged↗
PubMed2006

Relaxing the rule of ten events per variable in logistic and Cox regression.

The rule of thumb that logistic and Cox models should be used with a minimum of 10 outcome events per predictor variable (EPV), based on two simulation studies, may be too conservative. The authors conducted a large simulation study of other influences on confidence interval coverage, type I error, relative bias, and other model performance measures. They found a range of circumstances in which coverage and bias were within acceptable levels despite less than 10 EPV, as well as other factors that were as influential as or more influential than EPV. They conclude that this rule can be relaxed, in particular for sensitivity analyses undertaken to demonstrate adequate control of confounding.

Bias↗
PubMed1981

Intelligence and left hemisphere disease. The role of aphasia, apraxia and size of lesion.

The Raven Progressive Matrices and four subtests of the Wechsler-Bellevue Performance Scale were given to 173 left hemisphere patients subdivided according to presence/absence, type (fluent/non-fluent) and severity (moderate/severe) of aphasia. Constructive and ideomotor apraxia scores and CT scan data of each subject entered the statistical analysis. Factors significant in producing a low score on Progressive Matrices and Wechsler-Bellevue were presence of aphasia and constructive apraxia. Site and size of lesion per se failed to account for the intelligence scores. The relationship between aphasia, apraxia, intelligence test scores, and CT scan data were discussed in an attempt to clarify the meaning of these low intelligence test scores in aphasics and to assess the underlying roles of the brain lesions in this deficit. It appears that there are a number of methodological difficulties complicating interpretation of the intellectual deficit based on the Progressive Matrices and Wechsler-Bellevue scores, since performance on these tests is adversely affected by both aphasia and apraxia.

Aphasia↗
PubMed2001

The dimensions of service quality for hospitals: development and use of the KQCAH scale.

Using a combination of qualitative and quantitative research methodologies, this study identifies the dimensions of hospital service quality, operationalizes the dimensions, and develops an instrument to measure patient satisfaction. This instrument, the Key Quality Characteristics Assessment for Hospitals (KQCAH) scale, was developed using input from 12 hospital administrators, over 100 hospital employees, and 23 recent patients and family members.

Attitude of Health Personnel↗
PubMed2001

Q methodology: a new way of assessing employee satisfaction.

As yet another nursing shortage faces the country, the issue of the satisfaction of nurses again becomes of critical concern to nursing managers in the interest of staff retention. The authors describe the use of the statistical technique Q methodology to assess the needs of nurses and other medical staff at a level one, tertiary care emergency department in the United States. Using the Q method, the authors were able to identify different, unique viewpoints concerning employee needs among the study population, as well as commonly shared views. This level of detail, not obtainable using more traditional statistical techniques, can aid in the design of more effective strategies aimed at fulfilling the needs of an organization's staff to increase their satisfaction.

Attitude of Health Personnel↗
PubMed2003

Structure and reliability of Ware's Patient Satisfaction Questionnaire III: patients' satisfaction with oncological care in the Netherlands.

BACKGROUND: The present study examined the structure and reliability of the Dutch version of the Patient Satisfaction Questionnaire III (PSQ III). The PSQ III was designed to measure technical competence, interpersonal manner, communication, time spent with doctor, financial aspects, and access to care. In the Dutch version, the financial items were left aside because these are not appropriate for the Dutch socialized system. OBJECTIVES: The main objectives were to assess response bias, the number of dimensions needed to describe the PSQ III items, and the reliability of the scales. In addition, distribution characteristics were examined and norm scores to interpret satisfaction scores in an oncological setting were presented. RESEARCH DESIGN: A cross-sectional survey study.SUBJECTS The study was comprised of 1594 cancer patients from eight hospitals. MEASURES: The Dutch version of the PSQ III. RESULTS: Approximately 14% of the respondents were found to demonstrate considerable response bias. Confirmative factor analyses were performed to test three theoretical models with a varying number of dimensions among those participants who did not demonstrate response bias. The original structure did not fit the data well, but support was found for a three-factor model (with interpersonal manner, communication, and time spent with doctor loading on one factor instead of separate factors) and a one-dimensional model. CONCLUSIONS: The PSQ III seems to be an appropriate measure of cancer patients' satisfaction, with the note that the number of dimensions may vary for different patient groups and/or care settings and that it is important to be aware of response bias.

Aged↗
PubMed2006

Overview of quantitative measurement methods. Equivalence, invariance, and differential item functioning in health applications.

BACKGROUND: Reviewed in this article are issues relating to the study of invariance and differential item functioning (DIF). The aim of factor analyses and DIF, in the context of invariance testing, is the examination of group differences in item response conditional on an estimate of disability. Discussed are parameters and statistics that are not invariant and cannot be compared validly in crosscultural studies with varying distributions of disability in contrast to those that can be compared (if the model assumptions are met) because they are produced by models such as linear and nonlinear regression. OBJECTIVES: The purpose of this overview is to provide an integrated approach to the quantitative methods used in this special issue to examine measurement equivalence. The methods include classical test theory (CTT), factor analytic, and parametric and nonparametric approaches to DIF detection. Also included in the quantitative section is a discussion of item banking and computerized adaptive testing (CAT). METHODS: Factorial invariance and the articles discussing this topic are introduced. A brief overview of the DIF methods presented in the quantitative section of the special issue is provided together with a discussion of ways in which DIF analyses and examination of invariance using factor models may be complementary. CONCLUSIONS: Although factor analytic and DIF detection methods share features, they provide unique information and can be viewed as complementary in informing about measurement equivalence.

Cross-Cultural Comparison↗
PubMed1995

Rectification of the primary data obtained by a patients' satisfaction survey.

Examines an attempt at implementation of a total quality management programme in a university hospital in the Czech Republic where patient satisfaction was found to be very high. Tentatively ascribes the "generosity error" to the historic experience of the population. Demonstrates that this factor may be compensated for by a mathematical process ("rectification"), which is derived from the assessment of every respondent's general scale.

Czech Republic↗
PubMed1988

Ovarian size in postmenopausal women.

Ovarian volumes have been determined by pelvic ultrasonography in 2246 apparently healthy postmenopausal women of whom 2221 were included in the statistical analysis. Factors associated with gonadal size have been identified, and reference ranges for derived indices have been determined for use (in association with criteria for abnormal morphology) in a screening programme for ovarian carcinoma. The right ovary was present in 98.9% of subjects and the left in 99.1%. The mean (SD; range) of right and left ovarian volumes were 3.58 (1.40; 1.00-14.01) and 3.57 (1.37; 0.88-10.9) ml respectively. Significant predictors of ovarian volume were years since the menopause, weight, parity, age at menopause, a history of hormone replacement therapy, and previously diagnosed breast cancer. Abnormal ovarian volumes were assessed from a score equal to the (observed mean log volume (MLV) minus the predicted MLV)/0.327. A simplified nomogram has been prepared for routine clinical use. The relative abnormality of one ovary was assessed from a ratio score equal to loge (larger ovarian volume/smaller ovarian volume)/0.211 compared with the 99th centile for the Gaussian distribution.

Age Factors↗
PubMed1974

Immunological studies of anergic patients.

Sixty-one patients with a variety of different illnesses were studied with respect to skin test anergy and the presence of serum chemotactic inhibitors. In initial testing, 55% of the patient tests demonstrated negative skin test responses to all six test antigens. Sera from 65% of these anergic patients were capable of suppressing the migration of normal polymorphonuclear leukocytes toward chemotactic factors. Statistical analysis of the association of anergy and chemotactic inhibitory sera resulted in a P value of <0.0005. Chemotactic inhibitory sera were also capable of suppressing monocyte chemotaxis. No association of chemotactic inhibitory activity and lymphocytotoxic antibody or suppressors of mitogen-induced lymphocyte blast transformation were noted. In addition, T-cell populations in some anergic patients were studied by the erythrocyte-binding technique. Erythrocyte-binding lymphocytes in anergic patients were significantly suppressed when compared to normal controls, but not when compared to skin test-positive patients. The data presented here indicate a close parallel between skin test anergy and the presence of serum chemotactic inhibitory activity. The exact relationship is yet undefined but may indicate the involvement of chemotactic inhibitors as immunological regulators in the host during a variety of systemic illnesses.

Journal Article↗