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1.
Ther Adv Musculoskelet Dis ; 14: 1759720X221114103, 2022.
Article in English | MEDLINE | ID: mdl-36148396

ABSTRACT

Background: Composite measures, like the Disease Activity Score for 28 joints (DAS28), are key primary outcomes in rheumatoid arthritis (RA) trials. DAS28 combines four different components in a continuous measure. When one or more of these components are missing the overall composite score is also missing at intermediate or trial endpoint assessments. Objectives: This study examined missing data patterns and mechanisms in a longitudinal RA trial to evaluate how best to handle missingness when analysing composite outcomes. Design: The Tumour-Necrosis-Factor Inhibitors against Combination Intensive Therapy (TACIT) trial was an open label, pragmatic randomized multicentre two arm non-inferiority study. Patients were followed up for 12 months, with monthly measurement of the composite outcome and its components. Active RA patients were randomized to conventional disease modifying drugs (cDMARDs) or Tumour Necrosis Factor-α inhibitors (TNFis). Methods: The TACIT trial was used to explore the extent of missing data in the composite outcome, DAS28. Patterns of missing data in components and the composite outcome were examined graphically. Longitudinal multivariable logistic regression analysis assessed missing data mechanisms during follow-up. Results: Two hundred and five patients were randomized: at 12 months 59/205 (29%) had unobserved composite outcome and 146/205 (71%) had an observed DAS28 outcome; however, 34/146 had one or more intermediate assessments missing. We observed mixed missing data patterns, especially for the missing composite outcome due to one component missing rather than patient not attending thier visit. Age and gender predicted missingness components, providing strong evidence the missing observations were unlikely to be Missing Completely at Random (MCAR). Conclusion: Researchers should undertake detailed evaluations of missing data patterns and mechanisms at the final and intermediate time points, whether or not the outcome variable is a composite outcome. In addition, the impact on treatment estimates in patients who only provide data at milestone assessments need to be assessed. Trial Registration ISRCTN Number: 37438295.

2.
J Endocr Soc ; 5(11): bvab147, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34611573

ABSTRACT

BACKGROUND: Adrenal Insufficiency (AI), especially iatrogenic-AI, is a treatable cause of mortality. The difficulty in obtaining 9 am cortisol levels means samples are taken at suboptimal times, including a substantial proportion in the afternoon. Low afternoon cortisol levels often provoke short Synacthen tests (SSTs). It is important that this does not lead to patients misdiagnosed with AI, exposing them to the excess mortality and morbidity of inappropriate steroid replacement therapy. METHODS: This retrospective study collected 60 178 cortisol results. Medical records, including subsequent SSTs of initial cortisol results measured after midday were reviewed. RESULTS: Receiver operating characteristic analysis (area under the curve: 0.89) on 6531 suitable cortisol values showed that a limit of <201.5 nmol/L achieved a sensitivity and specificity of 95.6% and 72.6%, while a limit of <234 nmol/L had a sensitivity of 100% and a specificity of 59.5%. Out of 670 SSTs, 628 patients passed. Of these, 140 would have otherwise failed if only their 30-min cortisol was assessed without the 60-min value. A 30- and 60-min SST cortisol cutoff of 366.5 nmol/L and 418.5 nmol/L, respectively, can achieve a sensitivity of >95% on the Abbott analyser platform. CONCLUSION: An afternoon cortisol >234 nmol/L excludes AI on Abbott analyser platforms. In patients who have an afternoon cortisol <234 nmol/L, including both 30- and 60-min SST cortisol values prevents unnecessary glucocorticoid replacement therapy in 22.3% of individuals in this study. The Abbott analyser SST cortisol cutoffs used to define AI should be 366.5 nmol/L and 418.5 nmol/L at 30 and 60 min, respectively. All patients remained well subsequently with at least 1-year longitudinal follow-up.

3.
Sci Rep ; 11(1): 8897, 2021 04 26.
Article in English | MEDLINE | ID: mdl-33903656

ABSTRACT

The PAM intervention is a behavioural intervention to support adherence to anti-hypertensive medications and therefore to lower blood pressure. This feasibility trial recruited 101 nonadherent patients (54% male, mean age 65.8 years) with hypertension and high blood pressure from nine general practices in the UK. The trial had 15.5% uptake and 7.9% attrition rate. Patients were randomly allocated to two groups: the intervention group (n = 61) received the PAM intervention as an adjunct to usual care; the control group (n = 40) received usual care only. At 3 months, biochemically validated medication adherence was improved by 20% (95% CI 3-36%) in the intervention than control, and systolic blood pressure was reduced by 9.16 mmHg (95% CI 5.69-12.64) in intervention than control. Improvements in medication adherence and reductions in blood pressure suggested potential intervention effectiveness. For a subsample of patients, improvements in medication adherence and reductions in full lipid profile (cholesterol 1.39 mmol/mol 95% CI 0.64-1.40) and in glycated haemoglobin (3.08 mmol/mol, 95% CI 0.42-5.73) favoured the intervention. A larger trial will obtain rigorous evidence about the potential clinical effectiveness and cost-effectiveness of the intervention.Trial registration Trial date of first registration 28/01/2019. ISRCTN74504989. https://doi.org/10.1186/ISRCTN74504989 .


Subject(s)
Hypertension , Medication Adherence , Primary Health Care , Aged , Female , Glycated Hemoglobin/metabolism , Humans , Hypertension/blood , Hypertension/drug therapy , Hypertension/physiopathology , Hypertension/psychology , Male , Middle Aged , United Kingdom
4.
Contemp Clin Trials ; 93: 105999, 2020 06.
Article in English | MEDLINE | ID: mdl-32302790

ABSTRACT

INTRODUCTION: Focal therapy (FT) targets individual areas of cancer within the prostate, providing oncological control with minimal side-effects. Early evidence demonstrates encouraging short-medium-term outcomes. With no randomized controlled trials (RCT) comparing FT to radical therapies, Comparative Healthcare Research Outcomes of Novel Surgery in prostate cancer (CHRONOS) will compare the cancer control of these two strategies. PATIENTS AND METHODS: CHRONOS is a parallel phase II RCT for patients with clinically significant non-metastatic prostate cancer, dependent upon clinician/patient decision, patients will enrol into either CHRONOS-A or CHRONOS-B. CHRONOS-A will randomize patients to either radical treatment or FT. CHRONOS-B is a multi-arm, multistage RCT comparing focal therapy alone to FT with neoadjuvant agents that might improve the current focal therapy outcomes. An internal pilot will determine the feasibility of, and compliance to, randomization. The proposed definitive study plans to recruit and randomize 1190 patients into CHRONOS-A and 1260 patients into CHRONOS-B. RESULTS: Primary outcome in CHRONOS-A is progression-free survival (transition to salvage local or systemic therapy, development of metastases or prostate-cancer-related mortality) and in CHRONOS-B is failure-free survival (includes the above definition and recurrence of clinically significant prostate cancer after initial FT). Secondary outcomes include adverse events, health economics and functional outcomes measured using validated questionnaires. CHRONOS is powered to assess non-inferiority of FT compared to radical therapy in CHRONOS-A, and superiority of neoadjuvant agents with FT in CHRONOS-B. CONCLUSION: CHRONOS will assess the oncological outcomes after FT compared to radical therapy and whether neoadjuvant treatments improve cancer control following one FT session.


Subject(s)
Ablation Techniques/methods , Prostatic Neoplasms/therapy , Ablation Techniques/adverse effects , Ablation Techniques/education , Androgen Antagonists/therapeutic use , Anilides/therapeutic use , Brachytherapy/adverse effects , Brachytherapy/economics , Brachytherapy/methods , Costs and Cost Analysis , Equivalence Trials as Topic , Finasteride/therapeutic use , Humans , Male , Neoadjuvant Therapy/methods , Neoplasm Recurrence, Local , Nitriles/therapeutic use , Progression-Free Survival , Prospective Studies , Prostatectomy/adverse effects , Prostatectomy/economics , Prostatectomy/methods , Prostatic Neoplasms/pathology , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Radiotherapy/adverse effects , Radiotherapy/economics , Radiotherapy/methods , Research Design , Tosyl Compounds/therapeutic use , United Kingdom
5.
Trials ; 17(1): 272, 2016 06 02.
Article in English | MEDLINE | ID: mdl-27255212

ABSTRACT

BACKGROUND: Most reported outcome measures in rheumatoid arthritis (RA) trials are composite, whose components comprise single measures that are combined into one outcome. The aims of this review were to assess the range of missing data rates in primary composite outcomes and to document the current practice for handling and reporting missing data in published RA trials compared to the Consolidated Standards of Reporting Trials (CONSORT) recommendations. METHODS: A systematic search for randomised controlled trials was conducted for RA trials published between 2008 and 2013 in four rheumatology and four high impact general medical journals. RESULTS: A total of 51 trials with a composite primary outcome were identified, of which 38 (75 %) used the binary American College of Rheumatology responder index and 13 (25 %) used the Disease Activity Score for 28 joints (DAS28). Forty-four trials (86 %) reported on an intention-to-treat analysis population, while 7 trials (14 %) analysed according to a modified intention-to-treat population. Missing data rates for the primary composite outcome ranged from 2-53 % and were above 30 % in 9 trials, 20-30 % in 11 trials, 10-20 % in 18 trials and below 10 % in 13 trials. Thirty-eight trials (75 %) used non-responder imputation and 10 (20 %) used last observation carried forward to impute missing composite outcome data at the primary time point. The rate of dropout was on average 61 % times higher in the placebo group compared to the treatment group in the 34 placebo controlled trials (relative rate 1.61, 95 % CI: 1.29, 2.02). Thirty-seven trials (73 %) did not report the use of sensitivity analyses to assess the handling of missing data in the primary analysis as recommended by CONSORT guidelines. CONCLUSIONS: This review highlights an improvement in rheumatology trial practice since the revision of CONSORT guidelines, in terms of power calculation and participant's flow diagram. However, there is a need to improve the handling and reporting of missing composite outcome data and their components in RA trials. In particular, sensitivity analyses need to be more widely used in RA trials because imputation is widespread and generally uses single imputation methods, and in this area the missing data rates are commonly differentially higher in the placebo group.


Subject(s)
Arthritis, Rheumatoid/therapy , Data Collection/methods , Patient Dropouts , Randomized Controlled Trials as Topic/methods , Research Design , Arthritis, Rheumatoid/diagnosis , Data Accuracy , Data Collection/statistics & numerical data , Data Interpretation, Statistical , Humans , Intention to Treat Analysis , Models, Statistical , Patient Dropouts/statistics & numerical data , Randomized Controlled Trials as Topic/statistics & numerical data , Research Design/statistics & numerical data , Sample Size , Treatment Outcome
6.
Br J Health Psychol ; 18(1): 122-38, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22988885

ABSTRACT

OBJECTIVE: Commonly used theories in health psychology involve multiplicative composites of measures, which have been used as predictors, mediators, and outcomes. The chosen scaling system can affect correlations with other variables. This study evaluated how best to construct composites in the context of the theory of planned behaviour (TPB), using hierarchical linear regression, a priori defined scaling systems, and optimal scaling. DESIGN: Longitudinal. METHODS: At baseline, 6 and 12 months, 365 trial participants (ProActive) completed questionnaires assessing salient beliefs, which were used to construct composites (indirect measures), and direct measures of instrumental and affective attitude, subjective norm, and perceived behavioural control towards becoming more physically active over the next 12 months. RESULTS: Linear regression supported a multiplicative model for indirect instrumental attitude and perceived control. Except for perceived control, associations between composites and direct measures were unaffected by different a priori scaling systems. Optimal scaling produced widely differing composites over time for subjective norm and affective attitude and a negative association between composite and direct measure for subjective norm. CONCLUSIONS: We recommend that researchers who use multiplicative composites first establish clear support for a multiplicative model, before they examine a range of meaningful scaling systems on theoretical and empirical grounds. Caution is needed when using optimal scaling without checking that a multiplicative model is supported and the resulting scaling system meaningful. STATEMENT OF CONTRIBUTION: What is already known on this subject? Multiplicative composites are included in commonly used theories in health psychology (e.g., theory of planned behaviour). Valid measures are needed as the choice of scaling system (e.g., unipolar or bipolar) can affect estimates of associations between composites and other variables. Ajzen has advocated the use of optimal scaling. What does this study add? The study shows that optimal scaling can result in meaningless measures. We recommend that health psychologists use optimal scaling with great caution and we provide alternative recommendations for constructing composites.


Subject(s)
Diabetes Mellitus, Type 2/prevention & control , Diabetes Mellitus, Type 2/psychology , Exercise/psychology , Health Behavior , Health Knowledge, Attitudes, Practice , Adult , England , Factor Analysis, Statistical , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Surveys and Questionnaires
7.
PLoS One ; 7(7): e40305, 2012.
Article in English | MEDLINE | ID: mdl-22792272

ABSTRACT

BACKGROUND: Urinary biomarkers for bladder cancer detection are constrained by inadequate sensitivity or specificity. Here we evaluate the diagnostic accuracy of Mcm5, a novel cell cycle biomarker of aberrant growth, alone and in combination with NMP22. METHODS: 1677 consecutive patients under investigation for urinary tract malignancy were recruited to a prospective blinded observational study. All patients underwent ultrasound, intravenous urography, cystoscopy, urine culture and cytologic analysis. An immunofluorometric assay was used to measure Mcm5 levels in urine cell sediments. NMP22 urinary levels were determined with the FDA-approved NMP22® Test Kit. RESULTS: Genito-urinary tract cancers were identified in 210/1564 (13%) patients with an Mcm5 result and in 195/1396 (14%) patients with an NMP22 result. At the assay cut-point where sensitivity and specificity were equal, the Mcm5 test detected primary and recurrent bladder cancers with 69% sensitivity (95% confidence interval = 62-75%) and 93% negative predictive value (95% CI = 92-95%). The area under the receiver operating characteristic curve for Mcm5 was 0.75 (95% CI = 0.71-0.79) and 0.72 (95% CI = 0.67-0.77) for NMP22. Importantly, Mcm5 combined with NMP22 identified 95% (79/83; 95% CI = 88-99%) of potentially life threatening diagnoses (i.e. grade 3 or carcinoma in situ or stage ≥pT1) with high specificity (72%, 95% CI = 69-74%). CONCLUSIONS: The Mcm5 immunoassay is a non-invasive test for identifying patients with urothelial cancers with similar accuracy to the FDA-approved NMP22 ELISA Test Kit. The combination of Mcm5 plus NMP22 improves the detection of UCC and identifies 95% of clinically significant disease. Trials of a commercially developed Mcm5 assay suitable for an end-user laboratory alongside NMP22 are required to assess their potential clinical utility in improving diagnostic and surveillance care pathways.


Subject(s)
Biomarkers, Tumor/urine , Carcinoma, Transitional Cell/diagnosis , Cell Cycle Proteins/urine , Nuclear Proteins/urine , Urinary Bladder Neoplasms/diagnosis , Aged , Area Under Curve , Carcinoma , Carcinoma, Transitional Cell/urine , False Positive Reactions , Female , Humans , Limit of Detection , Male , Middle Aged , ROC Curve , Statistics, Nonparametric , Urinary Bladder Neoplasms/urine
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