Melody Ni

Melody Ni
Imperial College London | Imperial · Department of Surgery and Cancer

PhD
creating value through health innovations

About

94
Publications
18,888
Reads
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1,579
Citations
Introduction
I am a decision analyst with particular interests in understanding and supporting decision making under risks and uncertainty. I have worked on improving safety of nasogastric tube feeding, assessing impact of terrorist attacks on transportation choices, and investigating proficiency gain in surgery. I am currently working on designing appropriate methods to support the design, development, assessment and adoption of medical technologies. http://london.dec.nihr.ac.uk
Additional affiliations
September 2019 - September 2019
Imperial College London
Position
  • Senior Researcher
January 2007 - present
Imperial College London
Position
  • Research Associate
October 2002 - present
The London School of Economics and Political Science
Position
  • Visiting Lecturer

Publications

Publications (94)
Article
Full-text available
Background Acute appendicitis is the most common surgical emergency and can represent a challenging diagnosis, with a negative appendectomy rate as high as 20 %. This review aimed to evaluate the clinical utility of individual biomarkers in the diagnosis of appendicitis and appraise the quality of these studies. MethodsA systematic review of the li...
Article
Full-text available
Background This study aimed to develop the Point-of-Care Key Evidence Tool (POCKET); a multi-dimensional checklist to guide the evaluation of point-of-care tests (POCTs) incorporating validity, utility, usability, cost-effectiveness and patient experience. The motivation for this was to improve the efficiency of evidence generation in POCTs and red...
Article
Introduction: Health technology assessments (HTA) are tools for policy making and resource allocation. Early HTAs are increasingly used in design and development of new technologies. Conducting early HTAs is challenging, due to a lack of evidence and significant uncertainties in the technology and the market. A multi-disciplinary approach is consid...
Article
PURPOSE The aim of this study was to examine the external validity of the randomized TIME trial, when minimally invasive esophagectomy (MIE) was implemented nationally in the Netherlands, using data from the Dutch Upper GI Cancer Audit (DUCA) for transthoracic esophagectomy. METHODS Original patient data from the TIME trial were extracted along wi...
Preprint
Full-text available
Background In a tertiary respiratory centre, large cohorts of patients are managed in an outpatient setting and require blood tests to monitor disease activity and organ toxicity. This requires either visits to tertiary centres for phlebotomy and physician review or utilisation of primary care services. Objectives This study aims to validate remote...
Article
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Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Background: The advent of COVID-19 has meant that patients with chronic diseases needed to shield, however, investigations were needed to guide continual management of their disease. Remote monitoring options were evaluated to ensure the standard of care is not compromised. Purpose and Hypoth...
Article
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Background NG (nasogastric) tubes are used worldwide as a means to provide enteral nutrition. Testing the pH of tube aspirates prior to feeding is commonly used to verify tube location before feeding or medication. A pH at or lower than 5.5 was taken as evidence for stomach intubation. However, the existing standard pH strips lack sensitivity, espe...
Conference Paper
Full-text available
Background Naso or oro-gastric feeding tubes are essential component of care in providing nutrition and medication in neonatal units. The existing standard pH strips lack sensitivity. As a result, neonates may require re-insertion or some cases require unnecessary x-rays. A new generation of ester impregnated pH strips have been developed, utilisin...
Article
Emerging data demonstrate long-term survival after salvage interventions for local or oligometastatic recurrence after planned curative resection for esophageal cancer, providing rationale for postoperative surveillance. However, the impact of intensive surveillance on oncologic outcome is unknown. This multicenter collaborative study aimed to char...
Article
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Background Improving the design of technology relies in part, on the reporting of performance failures in existing devices. Healthcare has low levels of formal reporting of performance and failure of medical equipment. This paper examines methods of reporting in the car industry and healthcare and aims to understand differences and identify opportu...
Article
Full-text available
Objectives This study investigated the barriers and facilitators to the adoption of point-of-care tests (POCTs). Design Qualitative study incorporating a constant comparative analysis of stakeholder responses to a series of interviews undertaken to design the Point-of-Care Key Evidence Tool. Setting The study was conducted in relation to POCTs us...
Article
Full-text available
Background Individuals with cystic fibrosis (CF) have an increased susceptibility to fungal infection/allergy, with triazoles often used as first-line therapy. Therapeutic drug monitoring (TDM) is essential due to significant pharmacokinetic variability and the recent emergence of triazole resistance worldwide. Objectives In this retrospective stu...
Article
Objective: To examine the impact of The National Training Programme for Laparoscopic Colorectal Surgery (Lapco) on the rate of laparoscopic surgery and clinical outcomes of cases performed by Lapco surgeons after completion of training. Summery background data: Lapco provided competency-based supervised clinical training for specialist colorecta...
Article
Full-text available
Background: High-quality documentation of dumping symptoms after esophagectomy is currently limited. The aim of the study was to describe the incidence of symptoms associated with dumping syndrome and their relationship with health-related quality of life after esophagectomy. Methods: The study cohort was identified from prospective IRB-approved...
Article
Full-text available
Background Complex surgical procedures including minimally invasive esophagectomy (MIE) are commonly associated with a period of proficiency gain. We aim to study the effect of reduced procedural interval upon the number of cases required to gain proficiency and adverse patient outcomes during this period from MIE.Methods All adult patients undergo...
Article
Introduction Individuals with chronic lung disease (eg, cystic fibrosis (CF)) often receive antimicrobial therapy including aminoglycosides resulting in ototoxicity. Extended high-frequency audiometry has increased sensitivity for ototoxicity detection, but diagnostic audiometry in a sound-booth is costly, time-consuming and requires a trained audi...
Article
Objective: The aim was to develop a reliable surgical quality assurance system for 2-stage esophagectomy. This development was conducted during the pilot phase of the multicenter ROMIO trial, collaborating with international experts. Summary of background data: There is evidence that the quality of surgical performance in randomized controlled t...
Article
Aims The TIME trial showed reduced pulmonary complications from minimally invasive esophagectomy (MIE) over an open approach, and led to widespread adoption of MIE in the Netherlands. The aim of this study was to compare clinical outcomes from minimally invasive esophagectomy in the DUCA (national dataset) and the TIME trial (RCT) for transthoracic...
Article
Background: Clinically significant deterioration of patients admitted to general wards is a recognized complication of hospital care. Rapid Response Systems (RRS) aim to reduce the number of avoidable adverse events. The authors aimed to develop a core quality metric for the evaluation of RRS. Methods: We conducted an international consensus pro...
Article
Objectives: To determine the length of the learning curve of femtosecond laser assisted cataract surgery (FLACS) by a risk-adjusted cumulative sum method. Materials and Methods: This was a retrospective review of the first 288 FLACS performed by 3 surgeons over a 12 month period. The learning curves were analysed separately for each surgeon and as...
Conference Paper
Introduction Individuals with Cystic Fibrosis (CF) often receive frequent, prolonged anti-infective therapy including aminoglycosides which result in ototoxicity. There are, however, no current national or international screening recommendations. Although high-frequency audiometry has increased sensitivity for early detection of drug-induced hearin...
Conference Paper
Full-text available
The reliability and clinical utility of a medical device are required to demonstrate its impact and to enhance its success in the market. To fully establish these attributes it is necessary to investigate the context of use and the needs of the users. In healthcare, there is a growing use of human factors and health economics methods to generate ev...
Article
Aims To test a hypothesis that cataract operating room (OR) productivity can be improved with a femtosecond laser (FL) using a hub-and-spoke model and whether any increase in productivity can offset additional costs relating to the FL. Methods 400 eyes of 400 patients were enrolled in a randomised-controlled trial comparing FL-assisted cataract su...
Article
Introduction. The slow adoption of innovation into healthcare calls into question the manner of evidence generation for medical technology. This paper identifies potential reasons for this including a lack of attention to human factors, poor evaluation of economic benefits, lack of understanding of the existing healthcare system and a failure to re...
Article
Full-text available
[This corrects the article DOI: 10.1186/s41512-016-0001-y.].
Conference Paper
Rationale Timely, accurate diagnosis of invasive aspergillosis (IA) is key to enable initiation of antifungal therapy in lung transplantation. Despite promising novel fungal biomarkers, the lack of a diagnostic gold-standard creates difficulty in determining utility. Objectives This study aimed to use latent class modelling of fungal diagnostics t...
Article
Full-text available
Aims (1) To model the process of use and usability of pH strips (2) to identify, through simulation studies, the likelihood of misreading pH strips, and to assess professional’s acceptance, trust and perceived usability of pH strips. Methods This study was undertaken in four phases and used a mixed method approach (an audit, a semi-structured in...
Data
Semi-structured interview—Results of standardised questionnaire. (DOCX)
Data
Online survey—Results of standardised questionnaire. (DOCX)
Data
Questionnaires and evaluation scales. (DOCX)
Data
Preliminary graphic representation of NG-tube and pH strips use. (TIF)
Data
Revised graphic representation of NG-tube and pH strips use. (TIF)
Article
Full-text available
Aim To provide a quantitative assessment of cataract theatre lists focusing on productivity and staffing levels/tasks using time and motion studies. Methods National Health Service (NHS) cataract theatre lists were prospectively observed in five different institutions (four NHS hospitals and one private hospital). Individual tasks and their timing...
Article
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Objectives The existing British National Patient Safety Agency (NPSA) safety guideline recommends testing the pH of nasogastric (NG) tube aspirates. Feeding is considered safe if a pH of 5.5 or lower has been observed; otherwise chest X-rays are recommended. Our previous research found that at 5.5, the pH test lacks sensitivity towards oesophageal...
Article
Full-text available
Objective To determine if use of point of care testing (POCT) is less costly than laboratory testing to the National Health Service (NHS) in delivering the NHS Health Check (NHSHC) programme in the primary care setting. Design Observational study and theoretical mathematical model with microcosting approach. Setting We collected data on NHSHC del...
Article
Full-text available
Aims To develop financial models which offset additional costs associated with femtosecond laser (FL)-assisted cataract surgery (FLACS) against improvements in productivity and to determine important factors relating to its implementation into the National Health Service (NHS). Methods FL platforms are expensive, in initial purchase and running co...
Conference Paper
Joris de Groot, Christiana Naaktgeboren, Hans Reitsma, Carl Moons Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, 3584 CG Utrecht, Netherlands Correspondence: Joris de Groot (j.degroot-17@umcutrecht.nl) A major contributor to the rising problem of overdiagnosis, with the subsequent risk of overtreatment, is t...
Article
Full-text available
Background Gastrointestinal cancers constitute the third most common cancers worldwide. Tumor markers have long since been used in the postoperative surveillance of these malignancies; however, the true value in clinical practice remains undetermined. Objective This study aimed to evaluate the clinical utility of three tumor markers in colorectal a...
Article
Full-text available
Background: Synthetic mesh (SM) has been used in the laparoscopic repair of hiatus hernia but remains controversial due to reports of complications, most notably esophageal erosion. Biological mesh (BM) has been proposed as an alternative to mitigate this risk. The aim of this study is to establish the incidence of complications, recurrence and re...
Conference Paper
When debiasing meets dread: an online study “reconstructing” preferences for transportation after the London bombings. A terrorist attack on public transport destructs not just lives, but also how we travel and think about it. We trace the impact of a terrorist attack and four debiasing interventions on choice and risk perception of transportation....
Article
Full-text available
Background: The primary aim of this study was to compare survival from neoadjuvant chemoradiotherapy plus surgery (NCRS) versus neoadjuvant chemotherapy plus surgery (NCS) for the treatment of esophageal or junctional adenocarcinoma. The secondary aims were to compare pathological effects, short-term mortality and morbidity, and to evaluate the ef...
Article
Full-text available
Objective Endoscopic mucosal resection (EMR) is established for the management of benign and early malignant upper GI disease. The aim of this observational study was to establish the effect of endoscopist procedural volume on mortality. Design Patients undergoing upper GI EMR between 1997 and 2012 were identified from the Hospital Episode Statist...
Article
Objective Endoscopic mucosal resection (EMR) is established for the management of benign and early malignant upper GI disease. The aim of this observational study was to establish the effect of endoscopist procedural volume on mortality. Design Patients undergoing upper GI EMR between 1997 and 2012 were identified from the Hospital Episode Statisti...
Article
Full-text available
Objectives Point-of-care (POC) C reactive protein (CRP) is incorporated in National Institute of Health and Care Excellence (NICE) guidelines for the diagnosis of pneumonia, reduces antibiotic prescribing and is cost effective. Aim To determine the barriers and facilitators to adoption of POC CRP testing in National Health Service (NHS) primary car...
Article
Background Minimal access surgery for gastrointestinal cancer has short-term benefits but is associated with a proficiency-gain curve. The aim of this study was to define national proficiency-gain curves for minimal access colorectal and oesophagogastric surgery, and to determine the impact on clinical outcomes. Methods All adult patients undergoi...
Article
Objective: The aim of the study was to assess whether there is a proficiency curve-like relationship between surgeon volume and operative mortality and determine the minimum surgeon volume for optimum operative mortality. Background: The inverse relationship between hospital volume and operative mortality is well-established for esophageal, gast...
Article
Full-text available
Point-of-care in vitro diagnostics (POC-IVD) are increasingly becoming widespread as an acceptable means of providing rapid diagnostic results to facilitate decision-making in many clinical pathways. Evidence in utility, usability and cost-effectiveness is currently provided in a fragmented and detached manner that is fraught with methodological ch...
Article
There is a lack of educational tools available for surgical teaching critique, particularly for advanced laparoscopic surgery. The aim was to develop and implement a tool that assesses training quality and structures feedback for trainers in the English National Training Programme for laparoscopic colorectal surgery. Semi-structured interviews were...
Article
The National Training Programme for laparoscopic colorectal surgery in England was implemented to ensure training was supervised, structured, safe and effective. Delegates were required to pass a competency assessment (sign-off) before undertaking independent practice. This study described the types of errors identified and associated these errors...
Article
The English National Training Programme for Laparoscopic Colorectal Surgery introduced a validated objective competency assessment tool to accredit surgeons before independent practice. The aim of this study was to determine whether this technical skills assessment predicted clinical outcomes. Established consultants, training in laparoscopic color...
Article
Full-text available
Point-of-care (POC) tests enable rapid results and are well established in medical practice. Recent advances in analytical techniques have led to a new generation of POC devices that will alter gastrointestinal diagnostic pathways. This review aims to identify current and new technologies for the POC diagnosis of gastrointestinal cancer. A structur...
Article
Multicentre, randomised, controlled trials (RCTs) provide level 1 evidence for surgery in the treatment of gastro-oesophageal cancer. This systematic review investigated whether standardisation of surgical techniques in RCTs reduces the variation in lymph-node harvest, in-hospital mortality, and locoregional cancer recurrence. The range in the coef...
Article
Full-text available
Nasogastric (NG) tubes are commonly used for enteral feeding. Complications of feeding tube misplacement include malnutrition, pulmonary aspiration, and even death. We built a Bayesian network (BN) to analyse the risks associated with available bedside tests to verify tube position. Evidence on test validity (sensitivity and specificity) was retrie...