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PubMed2005

Nomograms including nuclear matrix protein 22 for prediction of disease recurrence and progression in patients with Ta, T1 or CIS transitional cell carcinoma of the bladder.

PURPOSE: We developed and validated nomograms that accurately predict disease recurrence and progression in patients with Ta, T1, or CIS transitional cell carcinoma (TCC) of the bladder using a large international cohort. METHODS: Univariate and multivariate logistic regression models targeted histologically confirmed disease recurrence, and focused on 2,542 patients with bladder TCC from 10 participating centers. Variables consisted of pre-cystoscopy voided urine Nuclear Matrix Protein 22 (NMP22) assay, urine cytology, age and gender. Resulting nomograms were internally validated with bootstrapping. Nomogram performance was explored graphically with Loess smoothing plots. RESULTS: Overall 957 patients had recurrent TCC. Tumor grade and stage was available for 898 patients, including 24% grade I, 43% grade II, and 33% grade III; 45% stage Ta, 32% T1 and/or CIS, and 23% T2 or greater. Bootstrap corrected predictive accuracy for any TCC recurrence was 0.842; grade III Ta/T1 or CIS was 0.869; and T2 or higher stage TCC of any grade was 0.858. Virtually perfect performance characteristics were observed for the nomograms predicting any TCC recurrence or grade III Ta/T1 or CIS. The nomogram predicting T2 or higher stage TCC overestimated the observed probability for predicted values greater than 45%. CONCLUSIONS: We developed and internally validated nomograms that incorporate urinary NMP22, cytology, age and gender to predict with high accuracy the probability of disease recurrence and progression in patients with Ta, T1, and/or CIS bladder TCC. These nomograms could provide a means for individualizing followup in patients with Ta, T1, CIS bladder TCC.

Adolescent↗

PubMed2005

Methodological issues in clinical trials of opioids for chronic pain.

Clinical trials of opioid analgesics for chronic pain are recognized to frequently fail to distinguish the analgesic effect from placebo, despite known efficacy of the drug. This paper reviews the methodologic features of such trials that may be associated with risk of failure. A literature search yielded 23 randomized placebo-controlled studies of opioids with at least one week of continuous treatment; contacting pharmaceutical companies yielded six additional studies. A classification system and standard terminology were developed for describing the methodologic features of these trials. The methodologic features that appeared to augur well for success of the trials were slow titration of medications, flexible dosing, minimizing concomitant and rescue analgesics, homogeneous samples, particularly in terms of opioid use upon entry, fewer study sites (for the same sample size), and including as much data as possible in statistical analyses. Study designs that lead to high dropout rates lack internal validity, unless dropout is the intended endpoint of the trial. Opioid analgesics should be studied in a manner that is clinically relevant, and that supports internal validity. More systematic attention is needed to clinical research methodology.

Analgesics, Opioid↗

PubMed2002

Factorial validity and internal reliability of Honey and Mumford's Learning Styles Questionnaire.

Honey and Mumford's Learning Styles Questionnaire was derived from the same conceptual basis as Kolb's Learning Style Inventory and may provide a more reliable and valid measure of Kolb's learning style constructs. The Learning Styles Questionnaire has not been psychometrically evaluated as extensively as the Learning Style Inventory. Since there is no published information on how the Learning Styles Questionnaire scales were derived, an attempt was made to factor analyze the responses to the questionnaire. Confirmatory factor analysis of 284 psychology undergraduates' responses identified a four-factor oblimin solution as the most satisfactory model investigated. Implications for interpretation and use within higher education are discussed.

Adolescent↗

PubMed1999

Questions on validity of International Classification of Diseases-coded diagnoses.

International Classification of Diseases (ICD) codes are used for indexing medical diagnoses for various purposes and in various contexts. According to the literature and our personal experience, the validity of the coded information is unsatisfactory in general, however the 'correctness' is purpose and environment dependent. For detecting potential error sources, this paper gives a general framework of the coding process. The key elements of this framework are: (1) the formulation of the established diagnoses in medical language; (2) the induction from diagnoses to diseases; (3) indexing the diseases to ICD categories; (4) labelling of the coded entries (e.g. principal disease, complications, etc.). Each step is a potential source of errors. The most typical types of error are: (1) overlooking of diagnoses; (2) incorrect or skipped induction; (3) indexing errors; (4) violation of ICD rules and external regulations. The main reasons of the errors are the physician's errors in the primary documentation, the insufficient knowledge of the encoders (different steps of the coding process require different kind of knowledge), the internal inconsistency of the ICD, and some psychological factors. Computer systems can facilitate the coding process, but attention has to be paid to the entire coding process, not only to the indexing phase.

Abstracting and Indexing↗

PubMed1995

Subclinical thought disorder in first-degree relatives of schizophrenic patients. Results from a matched-pairs study with the Thought Disorder Index.

To assess the frequency and quality of formal thought disorder in schizophrenic patients and their first-degree relatives, a consecutive series of 36 unmedicated patients, 20 siblings of these patients and 37 normal control subjects were examined with Holzman's Thought Disorder Index (TDI). As a proof of the internal validity of this tool, the patients demonstrated significantly more thought disorder than the controls as measured by the TDI total score and various subscores, which proved the internal validity of this tool in a German-speaking sample. In addition, in a pairwise comparison with controls who were individually matched by age and sex the patients' siblings had a significantly higher total TDI score and nonsignificant elevations on several subscores (combinatory and flippant). As to the level of severity of the thought disorder, the siblings mostly took an intermediate position between patients and controls. In conjunction with previous reports from other authors, our findings lend further support to the notion of subclinical thought disorder as an indicator of familial vulnerability to schizophrenia.

Adult↗

PubMed2004

Broth microdilution susceptibility testing for Leptospira spp.

Leptospirosis in humans has traditionally been treated with penicillin or doxycycline. The choice of therapy offered at the time of initial patient presentation is often empirical, as definitive diagnosis can take weeks. Determining the activity of numerous antimicrobial agents against a wide range of Leptospira serovars may broaden empirical therapeutic options. Various antimicrobials have been shown to be active against a limited number of serovars in in vitro studies, chiefly by the use of broth macrodilution techniques. We developed a broth microdilution technique using the commercially available growth indicator alamarBlue. MICs produced by this technique were compared to MICs and minimal bactericidal concentrations produced by the traditional broth macrodilution technique. The internal validity of our methods was assessed with 11 runs over numerous days with a single isolate of Leptospira interrogans serovar Icterohaemorrhagiae. By either method, the MICs for these internal-validity runs fell within 2 dilutions of each other for more than 90% of antimicrobials. A broader application of these two techniques included 12 serovars (including seven species) of Leptospira and six antimicrobials (penicillin G, doxycycline, chloramphenicol, erythromycin, cefotaxime, and ciprofloxacin). Observed reproducibility fell within 2 dilutions for 99% of the duplicate result sets for the MIC microdilution method, compared to 89% for the MIC macrodilution method. The macrodilution method tended to have a higher MIC at which 90% of the isolates were inhibited (MIC(90)) than did the microdilution method, but the MIC(90)s of both methods were within 2 dilutions of each other for all six drugs. The macrodilution and microdilution techniques produced similar results, with microdilution allowing a faster, more streamlined method of producing MIC results.

Anti-Bacterial Agents↗

PubMed2006

Self-monitoring of glucose in type 2 diabetes mellitus: a Bayesian meta-analysis of direct and indirect comparisons.

OBJECTIVE: To evaluate the relative effectiveness of interventions with self-monitoring blood glucose and self-monitoring of urine glucose, versus interventions without self-monitoring, in terms of HbA(1c) reductions in type 2 diabetes mellitus. METHODS: Thirteen published full reports on randomised controlled trials investigating the effects of self-monitoring glucose were identified by a systematic search of Medline, Embase, the Cochrane Library (1966-Nov 2005) and previous reviews. Three types of studies were included: self-monitoring of blood glucose versus no self-monitoring, self-monitoring of blood glucose versus self-monitoring of urine glucose and self-monitoring of blood glucose with regular feedback versus monitoring without feedback. The internal validity of studies was assessed systematically by two reviewers, using 13 criteria of a validated list. Results from the three types of studies were analysed simultaneously with a Bayesian metaanalysis of direct and indirect comparisons. RESULTS: Adjusted for baseline HbA(1c) level and internal validity, interventions with self-monitoring of blood glucose showed a reduction in HbA(1c) of 0.40 percentage-points (%) (95% credible interval [CrI] 0.07 to 0.70%) in comparison to interventions without self-monitoring. Regular feedback more than doubled the HbA(1c) reduction. Self-monitoring of urine glucose showed comparable results to interventions without self-monitoring (0.02% decrease in HbA(1c); 95% CrI -0.62 to 0.70%). There is a 88% probability that interventions with self-monitoring blood glucose are more effective than interventions with urine glucose monitoring (relative reduction in HbA(1c) is 0.38%, 95% CrI -0.30 to 1.00%). CONCLUSION: The randomized clinical trials performed to date provided positive results on the effectiveness of interventions with self-monitoring of blood glucose in type 2 diabetes mellitus. Regular medical feedback of the monitored HbA(1c) levels is important. Furthermore, self-monitoring of blood glucose is likely to be more effective than self-monitoring of urine glucose.

Bayes Theorem↗

PubMed2006

Validation of International Classification of Functioning, Disability, and Health (ICF) Core Sets for early postacute rehabilitation facilities: comparisons with three other functional measures.

OBJECTIVE: Short lists of International Classification of Functioning, Disability, and Health (ICF) categories, ICF Core Sets, have been developed as reference standards for clinical practice and research. The objective of this study was to validate the ICF Core Sets for early postacute rehabilitation facilities against the measures most commonly used in early postacute rehabilitation, the FIM instrument, the Functional Assessment Measure, and the Barthel index. DESIGN: Linking study matching the concepts of three commonly used outcome measures to corresponding ICF categories. RESULTS: Corresponding ICF categories could be found for all of the items of the FIM instrument + Functional Assessment Measure and Barthel index. The 40 items of these three measures were linked to 33 different ICF categories. Four items could be linked to ICF categories that were not part of any of the Postacute ICF Core Sets. CONCLUSIONS: The Postacute ICF Core Sets cover the concepts of the most frequently used measures in early postacute rehabilitation. Yet, many aspects of human functioning are not measured by the FIM instrument + Functional Assessment Measure and the Barthel index. If this information is considered relevant, these items would have to be added by using supplementary measures. Our comparison demonstrates the benefit of using a common language when comparing items using different wordings and concepts.

Activities of Daily Living↗

PubMed1986

Satisfaction of continuity patients in a family medicine residency--validation of a measurement tool.

Patient satisfaction with resident physicians and patient satisfaction with faculty physicians was investigated in three clinical centers of a county hospital-based family medicine residency. Only patients in a continuity relationship (minimum 5 visits) were studied. Utilizing a previously validated Patient Satisfaction Questionnaire (PSQ), the dimensions of access, availability, continuity, finances, physician humaneness, and physician quality/competence were measured. Although there was little discriminant power between the measures of physician humaneness and quality/competence of care, overall internal validity was high. Availability and finances created the most dissatisfaction. Residents' care was reported to be as satisfying as that delivered by faculty physicians. Differentiation between system dependent factors and physician-dependent factors may be difficult among patients with a demonstrated continuity relationship. Nevertheless this study demonstrated a high internal validity for the short form of the PSQ in yet another practice setting. This instrument is available for further investigation in clinical settings.

Adult↗

PubMed2006

Validation of complex interventions in a low back pain trial: selective video analysis cross-referenced to clinical case notes.

INTRODUCTION: Auditing the interventions used in clinical trials to demonstrate that treatment protocols were adhered to and that discrete modalities were delivered, is essential in establishing internal validity. Pragmatic studies involving complex interventions provide a particular challenge. The value of case report forms which document individual treatment content relies upon accurate recall and recording by the clinician. This report describes a method to validate this type of data in a randomised clinical trial, by using video analysis on a sample of patient therapist interactions. METHODS: Six physiotherapists used standardised case report forms to record the treatment given to 402 patients recruited into the two treatment arms of a low back pain clinical trial. An audit checklist comprising the principal components of both management approaches was designed. Twelve treatment sessions were video recorded. Three independent clinicians viewed the recordings, using the checklist to identify the treatment content. These data were compared for agreement with the matching case report forms. The content of the interventions delivered to all of the trial patients was then audited. RESULTS: Agreement between the video observers, and between the observers and the case report forms ranged from moderate to very good (kappa=0.45-0.82). When compared with the video observations, some under-reporting of treatment occurred on the case report forms. Overall, 80% of the patients received the treatment to which they were allocated. CONCLUSIONS: This study has demonstrated that selective use of video recording, cross-referenced to clinical case notes may provide a feasible and relatively inexpensive means of establishing the internal validity of the interventions used in a pragmatic clinical trial.

Clinical Protocols↗

PubMed2004

Measuring stigma in children with epilepsy and their parents: instrument development and testing.

PURPOSE: The goal of this work is to describe psychometric properties of two scales measuring perceived stigma in children with epilepsy and their parents. METHODS: Data were collected for the parent scale in two samples: parents of 173 children with epilepsy and of 224 children with new-onset seizures. The child scale was tested in the chronic sample. Content validity, internal consistency reliability, and construct validity were tested. RESULTS: Both scales had strong internal consistency reliability and construct validity. Higher scores were associated with greater seizure severity scores. In the parent scale, lower scores were associated with more positive mood, less worry, and more family leisure activities. In the child scale, higher scores were correlated with more negative attitude, greater worry, poorer self-concept, and more depression symptoms. CONCLUSIONS: Both scales were found to have strong psychometric properties. They are short, and items are easy to understand. These scales have potential for use in research and in the clinical setting to measure stigma.

Adolescent↗

PubMed1995

Qualitative assessment of studies included in a meta-analysis: DES and the risk of pregnancy loss.

Meta-analysis, the qualitative and quantitative integration of available research information, is increasingly used in clinical research. This report examines the qualitative elements of meta-analysis through critical review of two published examples that assessed the effect of diethylstilboestrol (DES) on miscarriage and neonatal mortality, respectively. Our subjective review showed the internal validity of three of five trials aggregated in the former meta-analysis to be severely compromised. The remaining two trials (data from which were aggregated in the latter meta-analysis), while internally valid, studied different clinical populations. Therefore, pooling of their results may have been clinically inappropriate. In conclusion, meta-analysis involves substantial elements of subjective judgment. Qualitative assessment of studies is of pivotal importance, because the validity of any summary estimate of effect hinges on both the methodologic quality and the combinability of the aggregated studies.

Abortion, Spontaneous↗

PubMed2006

Systematic review: the effectiveness of hypnotherapy in the management of irritable bowel syndrome.

AIM: To systematically review the literature evaluating hypnotherapy in the management of irritable bowel syndrome (IBS). METHODS: Electronic databases were searched (Cochrane Library, Medline, CINAHL, AMED, Embase, PsycINFO, CISCOM, TRIP and the Social Science Citation index), bibliographic references scanned and main authors contacted. No restrictions were placed on language or publication year. Eligible studies involved adults with IBS using single-component hypnotherapy. All studies, except single case or expert opinion, were sought and all patient-related outcomes eligible. RESULTS: Out of 299 unique references identified, 20 studies (18 trials of which four were randomized, two controlled and 12 uncontrolled) and two case series were eligible. These tended to demonstrate hypnotherapy as being effective in the management of IBS. Numbers of patients included were small. Only one trial scored more than four out of eight on internal validity. CONCLUSION: The published evidence suggests that hypnotherapy is effective in the management of IBS. Over half of the trials (10 of 18) indicated a significant benefit. A randomized placebo-controlled trial of high internal validity is necessary to establish the effectiveness of hypnotherapy in the management of IBS. Until such a trial is undertaken, this form of treatment should be restricted to specialist centres caring for the more severe forms of the disorder.

Adult↗

PubMed2006

Are we honestly studying malingering? A profile and comparison of simulated and suspected malingerers.

Malingering research typically uses analog simulation design or differential prevalence design among "real" patients. Both have been criticized for methodological limitations in external and internal validity, respectively. Samples of simulated malingerers were compared to suspected malingerers to examine generalizability of analog findings. Overall results support the use of simulation designs. Furthermore, it was demonstrated that stringent selection of suspected malingerers maintains internal validity of the differential prevalence design. A second focus, to determine if demographic matching of simulated malingerers is necessary, showed that matching on age and race is not necessary.

Achievement↗

PubMed2026

Could the preoperative urethral curve be used to predict immediate urinary continence following Retzius-sparing robot-assisted radical prostatectomy? A retrospective multi-center study.

PURPOSE: Immediate urinary continence (UC) recovery following Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) remains highly variable, highlighting the need for reliable preoperative prediction. We aimed to develop and validate models to identify patients likely to achieve immediate UC recovery following RS-RARP. MATERIALS AND METHODS: A total of 580 prostate cancer patients who underwent RS-RARP from four medical centers were assigned to a training set (n=348), an internal validation set (n=103) and an external validation set (n=129). Independent predictors were identified through univariate analysis and LASSO regression. A nomogram was constructed using multivariate logistic regression. Its performance was evaluated with receiver operating characteristic (ROC) curve, calibration curves, and decision curve analysis. RESULTS: Immediate UC recovery was observed in 84.5% (294/348) of patients in the training cohort, 80.6% (83/103) in the internal validation cohort, and 81.4% (105/129) in the external validation cohort, respectively. Multivariate analysis identified membranous urethral length (MUL) (OR=1.23, P=0.029) and urethral curvature (OR=2.84, P<0.001) as independent predictors, while prostate volume (PV) (OR=0.84, P <0.001) as a protective factor. The nomogram integrating MUL, PV, and urethral curvature demonstrated superior predictive accuracy, with an AUC of 0.87 (95% CI, 0.83-0.91) in the training cohort. The bootstrap-corrected calibration slope was 0.96, and the Brier score was 0.08. Calibration curves and decision curve analysis confirmed the predictive accuracy and clinical utility of the nomogram. CONCLUSIONS: Our study introduces a novel quantitative method for assessing urethral curvature. The mpMRI-based model, integrating urethral curvature and prostate spatial configuration, offers enhanced predictive accuracy for postoperative immediate UC recovery.

Humans↗

PubMed2025

Radiogenomic MRI biomarkers for noninvasive prediction of GPC3 expression and tumor microenvironment in hepatocellular carcinoma.

BACKGROUND: Glypican-3 (GPC3) is frequently overexpressed in hepatocellular carcinoma (HCC) and plays a key role in immune and metabolic remodeling of the tumor microenvironment. Reliable noninvasive biomarkers for predicting GPC3 status could improve patient stratification and support precision immunotherapy. METHODS: This multicenter retrospective study included 274 patients with pathologically confirmed hepatocellular carcinoma from three institutions, 34 external cases with MRI from The Cancer Imaging Archive, and 363 transcriptomic profiles from The Cancer Genome Atlas. Contrast-enhanced T1-weighted imaging and diffusion-weighted imaging were analyzed. Tumor and peritumoral regions were segmented manually and radiomic features extracted using PyRadiomics. Feature selection was performed with correlation filtering and least absolute shrinkage and selection operator regression. Machine learning classifiers including logistic regression, random forest, support vector machine, k-nearest neighbor, and decision tree were trained with 10-fold cross-validation and tested on independent external cohorts. A radiomics score was calculated for each patient. Radiogenomic analysis correlated radiomics scores with transcriptomic data using weighted gene co-expression network analysis. Hub genes and enriched pathways were identified, and immune infiltration and predicted immunotherapy response were assessed using computational methods. RESULTS: The random forest model using contrast-enhanced T1-weighted imaging achieved an area under the curve of 0.966 in training and 0.935 in internal validation. The integrated contrast-enhanced T1-weighted imaging plus diffusion-weighted imaging model reached an internal validation area under the curve of 0.979. In external testing, the best performance was obtained with a support vector machine model (area under the curve 0.756). Radiomics scores were significantly correlated with GPC3 expression (R = 0.78, p < 0.05). Transcriptomic analysis identified a 10-gene signature enriched in hypoxia and lipid metabolism pathways that stratified patients into prognostic subgroups (concordance index 0.720, hazard ratio 4.07, p < 0.0001). High-risk patients had greater immune infiltration and a lower predicted immune evasion score, suggesting a potential benefit from immunotherapy. CONCLUSIONS: MRI-based radiomics models can noninvasively predict GPC3 expression in hepatocellular carcinoma. Radiomics scores reflect underlying hypoxia and lipid metabolism pathways and stratify patients by prognosis and predicted immunotherapy response. These findings support radiogenomics as a translational approach to imaging-guided precision treatment in hepatocellular carcinoma.

Humans↗

PubMed2003

Effectiveness of physiotherapy for lateral epicondylitis: a systematic review.

AIM: To evaluate the available evidence of the effectiveness of physiotherapy for lateral epicondylitis of the elbow. METHOD: Randomised controlled trials (RCTs) identified by a highly sensitive search strategy in six databases in combination with reference checking. Two independent reviewers selected RCTs that included a physiotherapy intervention, patients with lateral epicondylitis, and at least one clinically relevant outcome measure. No language restrictions were made. Methodological quality was independently assessed by two blinded reviewers. A best evidence synthesis, including a quantitative and qualitative analysis, was conducted, weighting the studies with respect to their internal validity, statistical significance, clinical relevance, and statistical power. RESULTS: 23 RCTs were included in the review, evaluating the effects of lasertherapy, ultrasound treatment, electrotherapy, and exercises and mobilisation techniques. Fourteen studies satisfied at least 50% of the internal validity criteria. Except for ultrasound, pooling of data from RCTs was not possible because of insufficient data, or clinical or statistical heterogeneity. The pooled estimate of the treatment effects of two studies on ultrasound compared to placebo ultrasound, showed statistically significant and clinically relevant differences in favour of ultrasound. There is insufficient evidence either to demonstrate benefit or lack of effect of lasertherapy, electrotherapy, exercises and mobilisation techniques for lateral epicondylitis. CONCLUSIONS: Despite the large number of studies, there is still insufficient evidence for most physiotherapy interventions for lateral epicondylitis due to contradicting results, insufficient power, and the low number of studies per intervention. Only for ultrasound, weak evidence for efficacy was found. More better designed, conducted and reported RCTs are needed.

Australia↗

PubMed1999

The health and cost effects of substituting home care for inpatient acute care: a review of the evidence.

BACKGROUND: There is much interest in reducing hospital stays by providing some health care services in patients' homes. The authors review the evidence regarding the effects of this acute care at home (acute home care) on the health of patients and caregivers and on the social costs (public and private costs) of managing the patients' health conditions. METHODS: MEDLINE and HEALTHSTAR databases were searched for articles using the key term "home care." Bibliographies of articles read were checked for additional references. Fourteen studies met the selection criteria (publication between 1975 and early 1998, evaluation of an acute home care program for adults, and use of a control group to evaluate the program). Of the 14, only 4 also satisfied 6 internal validity criteria (patients were eligible for home care, comparable patients in home care group and hospital care group, adequate patient sample size, appropriate analytical techniques, appropriate health measures and appropriate costing methods). RESULTS: The 4 studies with internal validity evaluated home care for 5 specific health conditions (hip fracture, hip replacement, chronic obstructive pulmonary disease [COPD], hysterectomy and knee replacement); 2 of the studies also evaluated home care for various medical and surgical conditions combined. Compared with hospital care, home care had no notable effects on patients' or caregivers' health. Social costs were not reported for hip fracture. They were unaffected for hip and knee replacement, and higher for COPD and hysterectomy; in the 2 studies of various conditions combined, social costs were higher in one and lower in the other. Effects on health system costs were mixed, with overall cost savings for hip fracture and higher costs for hip and knee replacement. INTERPRETATION: The limited existing evidence indicates that, compared with hospital care, acute home care produces no notable difference in health outcomes. The effects on social and health system costs appear to vary with condition. More well-designed evaluations are needed to determine the appropriate use of acute home care.

Acute Disease↗