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PubMed2026

Large-Scale Plasma Proteomics Enhances Prediction of Liver-Related Events Among Individuals With Prediabetes and Type 2 Diabetes: A Prospective Cohort Study in the UK Biobank.

OBJECTIVE: To develop a protein risk score (ProRS) for predicting liver-related events (LREs) in patients with diabetes and compare its predictive performance with the Fibrosis-4 Index (FIB-4) and an established polygenic risk score. RESEARCH DESIGN AND METHODS: This prospective cohort study included 13 516 individuals with prediabetes and type 2 diabetes (T2D) from the UK Biobank. Cox proportional hazards models and LASSO regression were applied to identify proteins associated with incident LREs and construct the ProRS. Predictive performance was assessed using Harrell's C-index, time-dependent area under the receiver operating characteristic curve, net reclassification improvement and integrated discrimination improvement. RESULTS: Over a median follow-up of 13.5 years, 171 (1.3%) incident LREs occurred. We identified 877 proteins associated with LRE risk, primarily enriched in inflammatory signalling, extracellular matrix remodelling and complement/coagulation cascades. In the training set, we developed a 24-protein ProRS (C-index, 0.842; 95% CI 0.797-0.884) that stratified individuals into low-, medium- and high-risk groups, with 10-year cumulative incidences of LREs of 0.2%, 1.2% and 14.2%, respectively. Compared with the low-risk group, the hazard ratio for LREs was 57.1 (95% CI 31.9-102) in the high-risk group. In the internal validation set, the ProRS model (C-index, 0.876; 95% CI 0.827-0.920) accurately predicted both short- and long-term LREs and outperformed FIB-4 index (C-index, 0.733; 95% CI 0.657-0.807) and polygenic risk score (C-index, 0.636; 95% CI 0.564-0.706). CONCLUSIONS: The protein risk score demonstrated superior performance compared with the FIB-4 index and the polygenic risk score in predicting incident LREs among individuals with prediabetes and T2D. The score allows stratification of individuals according to liver-related risk, though external validation in multi-ethnic cohorts is warranted.

Humans↗

PubMed2002

Semiparametric maximum likelihood for nonlinear regression with measurement errors.

This article demonstrates semiparametric maximum likelihood estimation of a nonlinear growth model for fish lengths using imprecisely measured ages. Data on the species corvina reina, found in the Gulf of Nicoya, Costa Rica, consist of lengths and imprecise ages for 168 fish and precise ages for a subset of 16 fish. The statistical problem may therefore be classified as nonlinear errors-in-variables regression with internal validation data. Inferential techniques are based on ideas extracted from several previous works on semiparametric maximum likelihood for errors-in-variables problems. The illustration of the example clarifies practical aspects of the associated computational, inferential, and data analytic techniques.

Algorithms↗

PubMed2002

A note on estimating crude odds ratios in case-control studies with differentially misclassified exposure.

Morrissey and Spiegelman (1999, Biometrics 55, 338 344) provided a comparative study of adjustment methods for exposure misclassification in case-control studies equipped with an internal validation sample. In addition to the maximum likelihood (ML) approach, they considered two intuitive procedures based on proposals in the literature. Despite appealing ease of computation associated with the latter two methods, efficiency calculations suggested that ML was often to be recommended for the analyst with access to a numerical routine to facilitate it. Here, a reparameterization of the likelihood reveals that one of the intuitive approaches, the inverse matrix method, is in fact ML under differential misclassification. This correction is intended to alert readers to the existence of a simple closed-form ML estimator for the odds ratio in this setting so that they may avoid assuming that a commercially inaccessible optimization routine must be sought to implement ML.

Case-Control Studies↗

PubMed2005

Maternal posture for cephalic version of breech presentation: a review of the evidence.

BACKGROUND: Maternal posture is commonly recommended to promote cephalic version of breech presentation during pregnancy, but the few studies conducted to examine the efficacy of this obstetric practice are inconclusive. The purpose of this systematic review was to evaluate the research evidence base for postural management of breech presentation. METHODS: This review critically examined the research on maternal posture for breech presentation using guidelines from the third United States Preventive Services Task Force. Database searches were conducted of Ovid Medline, Cumulative Index of Nursing and Allied Health Literature, PubMed, and Cochrane Database of Systematic Reviews, using the keywords "pregnancy," "maternal posture," "maternal position," "postural management," "breech," "presentation." Hand searches were conducted on reference citations from databases, and all research articles, commentaries, and reports of clinical cases were included. RESULTS: Conceptual and methodological issues in the individual studies posed threats to internal validity in each study. Interpretation of the nonsignificant results in the research reports is debatable because the randomized controlled trials were underpowered, and flaws in each study challenged validity of the results. Meta-analysis of previous findings may be inappropriate. CONCLUSIONS: Further research based on explicit theory and improved methods, including sufficient sample size, is needed to determine whether maternal posture promotes cephalic version for pregnant women with breech presentation.

Breech Presentation↗

PubMed1991

Great expectations: some suggestions for applying the balanced placebo design to nicotine and smoking.

There are a number of methodological problems with the traditional placebo-controlled design used to investigate the effects of nicotine in human subjects. For example, the experimental instructions may create a 'guessing set' in the participants such that they search for possible clues to try to identify which condition they are in. If they guess correctly, the internal validity of the design may be threatened. Furthermore, by attempting to control for the effect of subjects' expectancies, the traditional placebo design precludes any estimate of expectancy effects. Continued use of this methodology in the smoking field is likely to lead to an overemphasis on pharmacological factors in smoking and a corresponding underemphasis on cognitive factors and nicotine-expectancy interactions. These problems can be overcome by the use of the balanced placebo design which orthogonally manipulates instructions (Told Nicotine versus Told Placebo) and nicotine (Received Nicotine versus Received Placebo). The balanced placebo design offers a powerful methodology for studying many aspects of smoking behaviour and nicotine effects, and three examples are given to illustrate its potential in this field: nicotine titration, nicotine and performance, and priming effects in smoking relapse.

Clinical Trials as Topic↗

PubMed2006

Public sector managed care: a comparative evaluation of substance abuse treatment in three counties.

AIMS: A study of publicly funded substance abuse treatment systems compared MidState, a county that reorganized its treatment system using managed care principles, to two other California counties that took different approaches, NorthState and SouthState. It was hypothesized that MidState would have better outcomes due to its emphasis on quality of care. DESIGN: This natural experiment compared the 'experimental' county, MidState, to two 'control' counties, assessing client outcomes following treatment. Administrative and historical exigencies that may affect system differences were explored in interviews with treatment program managers and staff. SETTINGS: Comparison counties were selected using treatment system and county census data, maximizing similarities to enhance internal validity. PARTICIPANTS: Adult clients (n = 681) were interviewed when beginning treatment and 12 months later (81% response rate). In addition, 50 treatment program managers and staff members across the three counties were interviewed during the year of client recruitment. MEASUREMENTS: Client interviews assessed functioning in the seven Addiction Severity Index domains-alcohol, drug, psychiatric, legal, employment, medical and family/social. FINDINGS: Outcomes (differences between baseline and 12 month composite scores) did not differ between counties in six of seven domains; in the seventh, psychiatric functioning, SouthState had better outcomes than MidState. Staff interviews indicated generally similar treatment strategies across counties, with MidState supplying greater oversight and performance standards. CONCLUSIONS: Managed care in public sector treatment generally did not result in poorer outcomes. Future attention in MidState to the barriers to successful implementation of individualized treatment, and to dual diagnosis treatment, might bring more positive results.

Adult↗

PubMed2005

Psychosocial morbidity of Graves' orbitopathy.

OBJECTIVE: Ocular diseases markedly impair daily function. In Graves' orbitopathy (GO), an associated psychosocial burden is present due to disfiguring proptosis and/or diplopia, signs with significant impact on functional status and well-being. We have therefore surveyed and assessed the psychosocial morbidity of GO. DESIGN: A prospective controlled study on subjects with GO using internationally validated, self-reporting questionnaires. PATIENTS: One hundred and two consecutive patients with varying degrees of severity and activity of GO. Measurements Emotional distress, coping styles and quality of life (QoL) were assessed by the Hospital Anxiety and Depression Scale, by a German adaptation of the Ways-of-Coping Checklist, and with the 36-item Short Form, respectively. Stressful events in the 6 months preceding diagnosis were registered with the Life Experience Survey. QoL findings were compared to German reference values, as well as to 102 age- and gender-matched patients, each with type 1 diabetes (insulin-dependent diabetes mellitus, IDDM) and inflammatory bowel disease (IBD), respectively. RESULTS: Compared to the German reference population, all QoL scales were at a lower rate and were especially decreased in subjects with active and/or severe GO, orbital pain, diplopia and stressful life events. Compared to diabetics, psychosocial scales were considerably reduced in GO (z = -1 vs. 0.1, P < 0.001) and higher scores for depressive coping (2.32 vs. 1.71, P < 0.001) and trivializing (2.37 vs. 1.97, P < 0.006) were noted. In GO, depressive coping and trivializing were negatively correlated with the mental (r = -0.603 and r =-0.411, both P < 0.001) and physical (r = -0.487 and r = -0.354, both P < 0.001) components of QoL. Depressive coping also positively correlated with anxiety (r = 0.636) and depression (r = 0.590), respectively, both P < 0.001. Emotional distress noted in 46 subjects, mostly with active and severe GO, was associated with poor QoL. Anxiety and depression were present in 41 and 24 GO patients, respectively. The number of stressful events positively correlated with the scores of anxiety (r = 0.3335) and depression (r = 0.3178), both P = 0.001. Foremost emotional distress, but also diplopia, stressful events and depressive coping had a major impact on QoL (proportion of variance explained = 13.1%, P < 0.001, multiple regression analysis). More than 75% of the psychosocial impairment in GO (R2= 0.76, P < 0.001) was associated with seven variables only (e.g. depression and anxiety). Six months prior to GO onset, 74 patients experienced a mean of 4 (range 0-13) stressful life events. Subjects with optic neuropathy had more stressful events than those without nerve involvement (5.1 vs. 2.7, P = 0.0425). CONCLUSIONS: Psychosocial morbidity is present in severe and/or active GO, which negatively affects QoL. The patients are not only physically ill, they also exhibit emotional distress. Accompanying psychosomatic treatment is indicated among about half of all GO patients.

Adaptation, Psychological↗

PubMed1984

Some problems associated with the measurement of community psychiatric nurse intervention.

This paper describes a study that was originally proposed to evaluate community psychiatric nurse intervention in terms of client outcome. Although the literature indicates the strong need for research of this nature, the strategy that it demands poses formidable methodological problems. These difficulties are examined within the framework of Campbell & Stanley's (1963) concept of 'internal validity'. Although the proposed design is assessed to be weak, it is argued that stringent appraisal of method can only strengthen the nursing profession's claim to produce research that is both credible and relevant.

Community Health Nursing↗

PubMed1994

The adaptation of an experimental sampling procedure for application in naturalistic psychiatric nursing research settings.

External constraints on random sampling remains a constant challenge to nurse researchers seeking control over patient recruitment when investigating the outcome of nursing treatments. Traditional non-random sampling strategies employed in naturalistic clinical settings are prone to extraneous variables that frequently compromise the internal validity of the research design and confidence in the results. This paper explores the value of the Buglass scale and minimization in the context of a quasi-experimental research study to examine the management of deliberate self-harm by community psychiatric nurses. Discussion centres on their scope for control of extraneous variables without sacrificing the naturalistic setting within which community psychiatric nurses operate. A worked example illustrates the sampling procedure for minimizing differences between subjects assigned to a treatment and comparison group.

Adolescent↗

PubMed1996

Endotracheal suctioning: an example of the problems of relevance and rigour in clinical research.

Endotracheal suctioning is a routine but potentially dangerous procedure. The literature documenting approaches to minimizing the cardiopulmonary complications of endotracheal suctioning is reviewed. Hyperoxygenation, hyperventilation, hyperinflation and the use of adaptors are all evaluated. The effects of endotracheal suctioning on haemodynamics and oxygen transport are also examined. The traditional dualist approach to the respiratory and cardiovascular systems is contrasted with the recent emphasis on oxygen transport by the cardiopulmonary system. The trade-off between the rigour of laboratory studies (which can be well controlled but are difficult to generalize) and the relevance of clinical research (which is more easily generalized but which often lacks internal validity) is discussed. Although research studies have become both more methodologically and conceptually sophisticated, definitive recommendations for a safe and effective suctioning procedure still remain elusive.

Clinical Nursing Research↗

PubMed2005

Speculum 'self-insertion': a pilot study.

AIM: This paper reports phase II of a pilot study that aimed to determine whether self-insertion of a speculum by women undergoing a pap smear would be more comfortable and lead to an improvement in satisfaction and a decrease in anxiety associated with this procedure. BACKGROUND: Research demonstrates that pelvic examinations are considered by most women to be unpleasant and are routinely associated with embarrassment, apprehension, fear and often some level of discomfort and/or pain. DESIGN: The study used quantitative and qualitative data collection techniques. Phase I (described elsewhere) tested the newly developed Speculum Self-Insertion Satisfaction Questionnaire for content validity, internal consistency and clarity. Phase II pilot study tested the technique of speculum self-insertion. Women's general level of anxiety was measured using the State Trait Anxiety Inventory, both before and after they performed the self-insertion procedure. Women's satisfaction and acceptance of the procedure was measured using the Speculum Self-Insertion Satisfaction Questionnaire and explored through the use of qualitative research techniques. PARTICIPANTS: A total of 198 women attending family planning clinics in Perth, Western Australia, between September and December 2003 were invited to participate in the study. One hundred and thirty-three women agreed to self-insert their own speculum. RESULTS: The study demonstrated that speculum self-insertion was acceptable to most women, especially younger women. Nearly 91% of women either agreed or strongly agreed that they were satisfied with the experience of self-insertion and would choose to self-insert the speculum again. This included the women who had not previously had a speculum examination. The quality of specimen collected was not detrimentally affected by speculum self-insertion. CONCLUSIONS: The results of this pilot research, while needing to be replicated in a larger study, demonstrate that offering women the opportunity to self-insert a speculum during a routine pelvic examination is an acceptable, innovative, simple and cost-neutral change in clinical practice that increases women's comfort and satisfaction and potentially makes sexual health screening less threatening to women of all ages. RELEVANCE TO CLINICAL PRACTICE: Speculum self-insertion may encourage women's attendance at clinics for regular screening. Early diagnosis and treatment will result in better health outcomes for women, families and the community at large.

Adolescent↗

PubMed1994

The Carmarthen audit project.

Experience within East Dyfed Mental Health Services of using externally designed audit tools has indicated a lack of ownership of the audit process by clinical staff. A project has been developed to initiate standard setting and measurement at clinical level, with an assumption that the development of an audit culture through an audit process is synonymous with ownership. An external appraisal system is being developed which can validate internal standard setting and measurement.

Community Mental Health Services↗

PubMed2006

Accurate model predicting sustained response at week 4 of therapy with pegylated interferon with ribavirin in patients with chronic hepatitis C.

Current models used to predict response to peginterferon plus ribavirin treatment, based on viral decline during the first 12 weeks of therapy, have focused on creating an early stopping rule to avoid unnecessary prolongation of therapy. We developed a multivariate model that predicted sustained virological response and nonresponse at baseline and during the first 12 weeks of therapy using collected data from 186 unselected patients with chronic hepatitis C treated with peginterferon plus ribavirin. This model employed ordinal regression with similarity least squares technology to assign the probability of a given outcome. Model variables include sex, age, prior treatment status, genotype, baseline serum alanine aminotransferase levels, histologic necroinflammation and fibrosis scores and serum hepatitis C virus RNA concentration at baseline and weeks, 4, 8, and 12. A multivariate model demonstrated high performance values at all time points. At baseline, the model demonstrated a negative predictive value (NPV) and a positive predictive value (PPV) of 91% and 95%, respectively. At week 4, these values improved to 97% and 100%, respectively, with 95% sensitivity, 89% specificity and 93% accuracy. At week 4, the model was equally efficient for naïve or previously treated patients. Internal validation demonstrated 90% PPV, 94% NPV, 95% sensitivity, 88% specificity and 92% accuracy. A week 4 stopping rule for patients with chronic hepatitis C treated with peginterferon with ribavirin might be proposed by using the model developed in our study.

Adult↗

PubMed2005

Individualised training to improve teaching competence of general practitioner trainers: a randomised controlled trial.

INTRODUCTION: In Flanders an important part of training to become a general practitioner (GP) is undertaken within a general practice. This requires a GP trainer to know how to facilitate learning processes. This paper reports a study focused on the research question: Does short but individualised training of GP trainers contribute to their teaching competence? METHOD: A total of 47 GP trainers were randomly divided into 2 groups of a pretest/post-test control group design. After a multiple-station teaching assessment test (MSTAT), the experimental group received a short but individualised training to improve teaching competence while the control group were given no specific programme regarding teaching competence. One year later, all participants were invited to sit the post-test. RESULTS: In all, 61 GP trainers participated in the pretest and 51 in the post-test; 44 GP trainers participated in both tests. Despite the large attrition, the internal validity of the experiment was preserved. Beginners gained a median score of 2.04 (on a scale of 0-5) on the first MSTAT. In the post-test, the experimental group (median = 3.12) scored significantly better on the entire test (Mann-Whitney U = 166.5, P < 0.05) compared with the control group (median = 2.84). However, the GP trainers in the control group also appeared to have made progress. CONCLUSION: General practitioners who start as GP trainers have insufficient teaching competence to guarantee good coaching of students. A personal programme leads to progress in teaching competence; however, it would seem that more time and support are necessary to allow GP trainers to gain full teaching competence. The fact that the control group made progress as well suggests that the test had an important learning effect.

Belgium↗

PubMed2006

Feasibility and usefulness of self-assessment of bleeding in patients with haematological malignancies, and the association between platelet count and bleeding.

BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the collection of daily prospective information about bleeding outcomes in patients with thrombocytopenia, including information obtained by patient self-assessment. MATERIALS AND METHODS: Consecutive patients with haematological malignancies were enrolled in a study of bleeding data collection during the period of thrombocytopenia. A short educational session and information sheet was designed for self-assessment. Platelet counts and all transfusions were recorded daily. Bleeding scores were translated into World Health Organization (WHO) bleeding grades. RESULTS: Nineteen patients were included in the study. Four-hundred and ten days of thrombocytopenia were eligible for assessment of bleeds. Self-assessment was feasible, as defined by the total proportion of days on which self-assessment was completed (70%, 288 thrombocytopenic days). There was 86% agreement between bleeding data collected by self-assessment and by medical examination using a structured assessment form. Examples of discrepancies included the duration of petechiae/bruises and the reporting of minor bleeding. There was no evidence for an association between patients' morning platelet count and daily WHO bleeding grade. The incidences of WHO grade 1 and grade 2 bleeding on days with platelet counts < or = 10 x 10(9)/l, 11-20 x 10(9)/l, and > 20 x 10(9)/l were similar and did not reveal higher rates of bleeding at lower counts. CONCLUSIONS: Patient self-assessment can help to support comprehensive daily prospective monitoring of bleeding, specifically facilitating data collection following hospital discharge. The discrepancies between self-assessment and medical examination highlight the need to develop a validated international assessment tool. The association among platelet count, risk of bleeding and role of prophylactic platelet transfusions needs further evaluation in larger prospective trials.

Female↗

PubMed2006

Systematic grading of surgical complications in live liver donors according to Clavien's system.

The lack of consensus on how to evaluate surgical complications of donors in live donor liver transplantation (LDLT) and incoherence of cumulative data hampers efficient comparison of the outcome worldwide. We considered that the application of the internationally validated classification system introduced by Clavien in 2004 might be beneficial. Operative complications of 243 patients who underwent live donor hepatectomy for adult LDLT between January 1996 and October 2005 at the University of Tokyo were analyzed according to the system. Definitions for each grade in the system are: grade I, deviation from the normal postoperative course but without the need for therapy; grade II, complication requiring pharmacologic treatment; grade III, complication with the need for surgical, endoscopic or radiological intervention (IIIa/b: without/with the need for general anesthesia); grade IV, life-threatening complication requiring intensive care; grade V, death. Surgical morbidity was recognized in 67 donors (28%). No deaths occurred. The numbers of patients with complications were: grade I, 36 (15%); II, 10 (4%); IIIa, 12 (5%); IIIb, 9 (4%); IV, 0; V, 0. Six in IIIb underwent surgical repair for bile leakage. Clavien's system is simple and informative. It may serve as a common tool for the quality assessment in live liver donor surgery worldwide, and we propose its application whenever surgical complication of live donor is discussed.

Adult↗

PubMed2004

Reliability of X-rays and bone scans for the assessment of changes in skeletal metastases from breast cancer.

AIMS: To examine the level of agreement among observers regarding changes between serial images of bone metastases. METHODS: Thirty-five pairs of bone X-rays and 30 pairs of bone scans were selected from the files of patients with breast cancer involving the skeleton. All images in a pair were of the same site and had been taken at least 12 weeks apart. Thirteen radiologists and 14 nuclear medicine physicians examined the X-ray and bone scan pairs, respectively. Each assessed whether the changes between sequential films represented improvement, stability or worsening. Inter-observer agreement was analysed using the kappa statistic (kappa). RESULTS: There was only fair overall agreement among radiologists regarding changes between X-rays (kappa = 0.23), but there was substantial agreement among nuclear medicine physicians for bone scan assessments (kappa = 0.62). Neither the experience of the observers nor the time between images had a significant effect on agreement. For X-rays, agreement was poorer if the response category was 'improvement' and if the type of bone lesion was mixed lytic/sclerotic. CONCLUSIONS: Evaluation of serial X-rays is unreliable for determining the response of bone metastases. Scintigraphic evaluation has a higher internal validity for the determination of response, but it should not be used in isolation from other clinical data.

Aged↗

PubMed2005

Male sexual function improves after ileal pouch anal anastomosis.

PURPOSE: Restorative Proctocolectomy and Ileal Pouch Anal Anastomosis has become the gold standard surgical therapy for the majority of patients with mucosal ulcerative colitis. However sexual functional disturbances after this procedure can be a concern for patients. Therefore the aim of this study was to determine the outcome of sexual-function related quality of life in male patients undergoing restorative proctocolectomy. METHODS: One hundred and twenty-two male patients who underwent restorative proctocolectomy with ileal pouch anal anastomosis between 1995 and 2000 were evaluated by the validated International Index of Erectile Function (IIEF) scoring instrument. This index scale examines sexual function in five categories. These are erectile function, orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction. The IIEF instrument was administered after surgery and then scores before and after RP/IPAA were evaluated and compared. The significance of age at the time of the surgery, type of surgery, type of anastomotic technique (mucosectomy vs stapled) and septic complications on sexual functional outcome were also investigated. RESULTS: Mean age at the time of the surgery was 39.9 +/- 11.5 years. The mean follow-up period (time between pouch surgery and IIEF completed) was 3.6 +/- 1.8 years. There was statistically significant improvement in 4 of 5 categories of sexual function (erectile function, sexual desire, intercourse satisfaction, and overall satisfaction) where patients had improved scores after surgery compared to prior to surgery. The mean erectile function score increased pre to post surgery by 2.12 points (P = 0.02), which indicates better sexual results. Anastomotic technique and septic complication did not influence the results, however, older age had a negative impact on results. CONCLUSIONS: Despite some adverse sexual functions, male patients who undergo RP/IPAA for the surgical management of their colitis may preserve or improve their overall sexual functional outcome.

Adult↗