Affiliation: University College London
- Simplifying a prognostic model: a simulation study based on clinical dataGareth Ambler
Department of Statistical Science, University College, 1 19 Torrington Place, London WC1E 7HB, UK
Stat Med 21:3803-22. 2002..Optimizing the Akaike information criterion appears to be appropriate for choosing the degree of simplification...
- Low-dose intravenous immunoglobulin treatment for complex regional pain syndrome (LIPS): study protocol for a randomized controlled trialAndreas Goebel
The University of Liverpool, Brownlow Hill, L69 7ZX Liverpool, UK
Trials 15:404. 2014..The development of novel, effective treatment technologies is, therefore, important. There are preliminary data suggesting that low-dose immunoglobulin treatment may significantly reduce pain from longstanding CRPS...
- An evaluation of penalised survival methods for developing prognostic models with rare eventsG Ambler
Department of Statistical Science, University College London, London, UK
Stat Med 31:1150-61. 2012..The ridge method generally performed the best, although lasso is recommended if variable selection is required...
- Non-linear models for the relation between cardiovascular risk factors and intake of wine, beer and spiritsGareth Ambler
Department of Statistical Science, University College London, 1 19 Torrington Place, London WC1E 6BT, UK
Stat Med 22:363-83. 2003..However, having clarified these issues, the apparent benefit of consuming wine instead of other alcoholic beverages may be relatively small...
- A comparison of imputation techniques for handling missing predictor values in a risk model with a binary outcomeGareth Ambler
Department of Statistical Science, University College London Joint UCLH UCL Biomedical Research Unit, London, UK
Stat Methods Med Res 16:277-98. 2007..MICE was amongst the best performing multiple imputation methods with regards to the quality of the predictions. Additionally, it produced the least biased estimates, with good coverage, and hence is recommended for use in practice...
- Generic, simple risk stratification model for heart valve surgeryGareth Ambler
Department of Statistical Science, University College, London, UK
Circulation 112:224-31. 2005..This study aims to develop a simple risk model to predict the risk of in-hospital mortality for patients undergoing heart valve surgery to provide information to patients and clinicians and to facilitate institutional comparisons...
- Recruitment of minority ethnic groups into clinical cancer research trials to assess adherence to the principles of the Department of Health Research Governance Framework: national sources of data and general issues arising from a study in one hospital trSylvia Godden
Department of Epidemiology and Public Health, Health Care Evaluation Group, UCL, London, England
J Med Ethics 36:358-62. 2010....
- Sociodemographic variations in the contribution of secondary drug prevention to stroke survival at middle and older ages: cohort studyRosalind Raine
Department of Epidemiology and Public Health, University College London, London WC1E 6BT
BMJ 338:b1279. 2009....
- Quality research in healthcare: are researchers getting enough statistical support?Rumana Z Omar
Research and Development, University College London Hospitals NHS Foundation Trust, Maple House, London W1P 9LL, UK
BMC Health Serv Res 6:2. 2006..This issue was highlighted several years ago and it was suggested that more investments were needed from health care organisations and Universities to alleviate this problem...
- Association between practice size and quality of care of patients with ischaemic heart disease: cross sectional studyAzeem Majeed
Primary Care Research Unit, School of Public Policy, University College London, London WC1H 9QU
BMJ 326:371-2. 2003
- Important determinants of self-efficacy in patients with chronic musculoskeletal painAnisur Rahman
Centre for Rheumatology, University College London, London, UK
J Rheumatol 31:1187-92. 2004..To define the presenting characteristics of a population of patients with chronic musculoskeletal pain seen in a tertiary rheumatology clinic, and to investigate which factors are associated with self-efficacy in these patients...
- Review and evaluation of penalised regression methods for risk prediction in low-dimensional data with few eventsMenelaos Pavlou
Department of Statistical Science, University College London, London, WC1E 6BT, U K
Stat Med 35:1159-77. 2016..Their use may aid variable selection, and they can be easily extended to clustered-data settings and to incorporate external information. © 2015 The Authors. Statistics in Medicine Published by JohnWiley & Sons Ltd. ..
- Cardiovascular risk and diabetes. Are the methods of risk prediction satisfactory?Jeffrey W Stephens
Department of Diabetes and Endocrinology, UCL Hospitals, Mortimer Street, London, UK
Eur J Cardiovasc Prev Rehabil 11:521-8. 2004..Our aim was to examine their efficacy in a clinic-based population of diabetic patients...
- Statistical analysis plan for the Laser-1st versus Drops-1st for Glaucoma and Ocular Hypertension Trial (LiGHT): a multi-centre randomised controlled trialVictoria Vickerstaff
Marie Curie Palliative Care Research Department, UCL Division of Psychiatry, University College London, 6th Floor, Maple House, 149 Tottenham Court Road, London, W1T 7NF, UK
Trials 16:517. 2015..This paper describes the statistical analysis plan for the study...
- Are multiple primary outcomes analysed appropriately in randomised controlled trials? A reviewVictoria Vickerstaff
Division of Psychiatry, University College London, 6th Floor, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK Department of Statistical Science, University College London, Gower Street, London WC1E 6BT, UK The Research Department of Primary Care and Population Health, University College London, Rowland Hill Street, London NW3 2PF, UK Electronic address
Contemp Clin Trials 45:8-12. 2015..We briefly describe the methods available to safeguard the inferences and to raise awareness of the potential problems caused by multiple outcomes...
- Sample size calculation for a stepped wedge trialGianluca Baio
Department of Statistical Science, University College London, Gower Street, London, UK
Trials 16:354. 2015..The specific features of SWTs need to be addressed properly in the sample size calculations to ensure valid estimates of the intervention effect...
- A note on obtaining correct marginal predictions from a random intercepts model for binary outcomesMenelaos Pavlou
Department of Statistical Science, University College London, Gower St, London, WC1E 6BT, UK
BMC Med Res Methodol 15:59. 2015..Clustered data with binary outcomes are often analysed using random intercepts models or generalised estimating equations (GEE) resulting in cluster-specific or 'population-average' inference, respectively...
- A prospective validation of the IOTA logistic regression models (LR1 and LR2) in comparison to subjective pattern recognition for the diagnosis of ovarian cancerNatalie Nunes
Gynaecological Diagnostic Outpatient Treatment Unit, University College Hospital Department of Statistical Science, University College London and Department of Women s Cancer, University College London, Elizabeth Garrett Anderson, Institute for Women s Health, London, United Kingdom
Int J Gynecol Cancer 23:1583-9. 2013..This study aimed to assess the accuracy of the International Ovarian Tumour Analysis (IOTA) logistic regression models (LR1 and LR2) and that of subjective pattern recognition (PR) for the diagnosis of ovarian cancer...
- DNA replication licensing factors and aneuploidy are linked to tumor cell cycle state and clinical outcome in penile carcinomaOliver J Kayes
Department of Pathology, University College London, London, United Kingdom
Clin Cancer Res 15:7335-44. 2009..We have analyzed replication licensing factors (RLF), together with DNA ploidy status, to investigate their role in progression of penile squamous cell carcinoma and to assess their utility as novel prognostic tools...
- Social variations in access to hospital care for patients with colorectal, breast, and lung cancer between 1999 and 2006: retrospective analysis of hospital episode statisticsRosalind Raine
Department of Epidemiology and Public Health, University College London, London WC1E 6BT
BMJ 340:b5479. 2010..To determine the extent to which type of hospital admission (emergency compared with elective) and surgical procedure varied by socioeconomic circumstances, age, sex, and year of admission for colorectal, breast, and lung cancer...
- Prevalence of conventional and lupus-specific risk factors for cardiovascular disease in patients with systemic lupus erythematosus: A case-control studyRupa Bessant
University College London, London, UK
Arthritis Rheum 55:892-9. 2006..We compared the prevalence of conventional and lupus-specific risk factors in patients with SLE just before a cardiovascular event and in matched controls with SLE but no cardiovascular disease (CVD)...
- Serum 25-hydroxy vitamin D levels in chronic fatigue syndrome: a retrospective surveySaul Berkovitz
Royal London Homeopathic Hospital, University College London Hospitals NHS Trust, London, UK
Int J Vitam Nutr Res 79:250-4. 2009..We hypothesized that serum 25-OH vitamin D levels are lower in CFS patients than in the general British population...
- Off-Pump Coronary Artery Bypass (OPCAB) surgery reduces risk-stratified morbidity and mortality: a United Kingdom Multi-Center Comparative Analysis of Early Clinical OutcomeSharif Al-Ruzzeh
National Heart and Lung Institute, Imperial College of Science, Technology and Medicine, Harefield Hospital, Middlesex UB9 6JH, United Kingdom
Circulation 108:II1-8. 2003....
- Cardiac surgery risk modeling for mortality: a review of current practice and suggestions for improvementRumana Z Omar
MRC Clinical Trials Unit London, London, United Kingdom
Ann Thorac Surg 77:2232-7. 2004..Model development and validation processes are not always linked to the clinical aim of the model, which may affect their clinical validity. We make some suggestions in this review for improvement in methodology and reporting...
- Case-mix and variation in specialist referrals in general practiceCaoimhe O Sullivan
University College London Hospital NHS Trust
Br J Gen Pract 55:529-33. 2005..The potential of a comprehensive measure of patient morbidity to explain variation in referrals to secondary care has not previously been examined in the UK...