Matthew Fell

Bio: Matthew Fell is an academic researcher from University of Bristol. The author has contributed to research in topics: Incidence (epidemiology) & Hard palate. The author has an hindex of 1, co-authored 6 publications receiving 3 citations.

Maternal Cigarette Smoking and Cleft Lip and Palate: A Systematic Review and Meta-Analysis.

Abstract: ObjectivesA systematic review and meta-analysis to determine the association between active maternal smoking and cleft lip and palate etiology.Data sourcesMedline, Embase, Web of Science and the Co...

The impact of changing cigarette smoking habits and smoke-free legislation on orofacial cleft incidence in the United Kingdom: Evidence from two time-series studies.

Abstract: BACKGROUND Both active and passive cigarette smoking have previously been associated with orofacial cleft aetiology. We aimed to analyse the impact of declining active smoking prevalence and the implementation of smoke-free legislation on the incidence of children born with a cleft lip and/or palate within the United Kingdom. METHODS AND FINDINGS We conducted regression analysis using national administrative data in the United Kingdom between 2000-2018. The main outcome measure was orofacial cleft incidence, reported annually for England, Wales and Northern Ireland and separately for Scotland. First, we conducted an ecological study with longitudinal time-series analysis using smoking prevalence data for females over 16 years of age. Second, we used a natural experiment design with interrupted time-series analysis to assess the impact of smoke-free legislation. Over the study period, the annual incidence of orofacial cleft per 10,000 live births ranged from 14.2-16.2 in England, Wales and Northern Ireland and 13.4-18.8 in Scotland. The proportion of active smokers amongst females in the United Kingdom declined by 37% during the study period. Adjusted regression analysis did not show a correlation between the proportion of active smokers and orofacial cleft incidence in either dataset, although we were unable to exclude a modest effect of the magnitude seen in individual-level observational studies. The data in England, Wales and Northern Ireland suggested an 8% reduction in orofacial cleft incidence (RR 0.92, 95%CI 0.85 to 0.99; P = 0.024) following the implementation of smoke-free legislation. In Scotland, there was weak evidence for an increase in orofacial cleft incidence following smoke-free legislation (RR 1.16, 95%CI 0.94 to 1.44; P = 0.173). CONCLUSIONS These two ecological studies offer a novel insight into the influence of smoking in orofacial cleft aetiology, adding to the evidence base from individual-level studies. Our results suggest that smoke-free legislation may have reduced orofacial cleft incidence in England, Wales and Northern Ireland.

Maternal cigarette smoking and cleft lip and palate: A systematic review and meta-analysis

Abstract: Objectives: A systematic review and meta-analysis to determine the association between active maternal smoking and cleft lip and palate etiology. Data Sources: Medline, Embase, Web of Science and the Cochrane database from inception to November 2020. Study selection: Observational studies of cigarette smoking habits in pregnant women. Outcomes included cleft lip and/or palate, cleft lip +- palate and cleft palate only. Data analysis: Publication bias analyses were performed and the Newcastle Ottawa scales were used to assess study quality. Fixed or random effect models were used in the meta-analysis, dependent on risk of statistical heterogeneity. Results: Forty-five studies were eligible for inclusion of which 11 were cohort and 34 were case-control studies. Sixteen studies were of sufficient standard for inclusion in the meta-analysis. The summary odds ratio for the association between smoking and cleft lip and/or palate was 1.42 (95%CI 1.27 to 1.59) with a population attributable fraction of 4% (95%CI 3% - 5%). There was limited evidence to show a dose-response effect of smoking. Conclusions: This review reports a moderate association between maternal smoking and orofacial cleft but the overall quality of the conventional observational studies included was poor. There is a need for high quality and novel research strategies to further define the role of smoking in the etiology of cleft lip and palate.

Adapting cleft care protocols in low- and middle-income countries during and after COVID-19: a process-driven review with recommendations

Abstract: Objective A consortium of global cleft professionals, predominantly from low- and middle-income countries, identified adaptions to cleft care protocols during and after COVID as a priority learning area of need. Design A multidisciplinary international working group met on a videoconferencing platform in a multi-staged process to make consensus recommendations for adaptions to cleft protocols within resource-constrained settings. Feedback was sought from a roundtable discussion forum and global organisations involved in comprehensive cleft care. Results Foundational principles were agreed to enable recommendations to be globally relevant and two areas of focus within the specified topic were identified. First the safety aspects of cleft surgery protocols were scrutinised and COVID adaptions, specifically in the pre and peri-operative periods, were highlighted. Second, surgical operations and access to services were prioritized according to their relationship to functional outcomes and time-sensitivity. The operations assigned the highest priority were emergent interventions for breathing and nutritional requirements and primary palatoplasty. The cleft services assigned the highest priority were new-born assessments, paediatric support for children with syndromes, management of acute dental or auditory infections and speech pathology intervention. Conclusions A collaborative, interdisciplinary and international working group delivered consensus recommendations to assist with the provision of cleft care in low- and middle-income countries. At a time of global cleft care delays due to COVID-19, a united approach amongst global cleft care providers will be advantageous to advocate for children born with cleft lip and palate in resource-constrained settings.

Current surgical practice for children born with a cleft lip and/or palate in the United Kingdom

Abstract: Background: This study describes primary surgical reconstructions performed for children born with a cleft lip and/or palate in the United Kingdom. Methods: Data were obtained from the Cleft Collective, a national longitudinal cohort study. Data forms completed at the time of surgery included details on timing, technique and adjuncts used during the operative period. Demographic data on participants were validated via parental questionnaires. Results: Between 2015 and 2021, 1782 Cleft Collective surgical forms were included, relating to the primary reconstructions of 1514 individual children. The median age at primary cheiloplasty was 4.3 months. Unilateral cleft lips were reconstructed with an anatomical subunit approximation technique in 53%, whereas bilateral cleft lips were reconstructed with a broader range of eponymous techniques. Clefts of the soft palate were reconstructed at a median age of 10.3 months with an intravelar veloplasty in 94% cases. Clefts of the hard palate were reconstructed with a vomer flap in 84% cases in a bi-modal age distribution, relating to reconstruction carried out simultaneously with either lip or soft palate reconstruction. Antibiotics were used in 96% of cases, with an at-induction-only regimen used more commonly for cheiloplasties (p<0.001) and a 5 to 7day post-operative regime used more commonly for soft palatoplasties (p<0.001). Peri-operative steroids were used more commonly in palatoplasties than cheiloplasties (p<0.001) but tranexamic acid use was equivalent (p=0.73). Conclusion: This study contributes to our understanding of current cleft surgical pathways in the United Kingdom and will provide a baseline for analysis of the effectiveness of utilised protocols.

Tools for assessing quality and risk of bias in Mendelian randomization studies: a systematic review

Abstract: Abstract Background The use of Mendelian randomization (MR) in epidemiology has increased considerably in recent years, with a subsequent increase in systematic reviews of MR studies. We conducted a systematic review of tools designed for assessing risk of bias and/or quality of evidence in MR studies and a review of systematic reviews of MR studies. Methods We systematically searched MEDLINE, Embase, the Web of Science, preprints servers and Google Scholar for articles containing tools for assessing, conducting and/or reporting MR studies. We also searched for systematic reviews and protocols of systematic reviews of MR studies. From eligible articles we collected data on tool characteristics and content, as well as details of narrative description of bias assessment. Results Our searches retrieved 2464 records to screen, from which 14 tools, 35 systematic reviews and 38 protocols were included in our review. Seven tools were designed for assessing risk of bias/quality of evidence in MR studies and evaluation of their content revealed that all seven tools addressed the three core assumptions of instrumental variable analysis, violation of which can potentially introduce bias in MR analysis estimates. Conclusion We present an overview of tools and methods to assess risk of bias/quality of evidence in MR analysis. Issues commonly addressed relate to the three standard assumptions of instrumental variables analyses, the choice of genetic instrument(s) and features of the population(s) from which the data are collected (particularly in two-sample MR), in addition to more traditional non-MR-specific epidemiological biases. The identified tools should be tested and validated for general use before recommendations can be made on their widespread use. Our findings should raise awareness about the importance of bias related to MR analysis and provide information that is useful for assessment of MR studies in the context of systematic reviews.

Tools for the assessment of quality and risk of bias in Mendelian randomization studies: a systematic review

Abstract: Background. The use of Mendelian randomization (MR) in epidemiology has increased considerably in recent years, with a subsequent increase in systematic reviews of MR studies. We conducted a systematic review of tools designed for risk of bias and/or quality of evidence assessment in (MR) studies, and a review of systematic reviews of MR studies. Methods. We systematically searched MEDLINE, Embase, the Web of Science, preprints servers and Google Scholar for articles containing tools for assessing, conducting and/or reporting MR studies. We also searched for systematic reviews and protocols of systematic reviews of MR. From eligible articles we collected data on tool characteristics and content, as well as details of narrative description of bias assessment. Results. Our searches retrieved 2464 records to screen, from which 14 tools, 35 systematic reviews and 38 protocols were included in our review. Seven tools were designed for assessing risk of bias/quality of evidence in MR studies and evaluation of their content revealed that all seven tools addressed the three core assumptions of instrumental variable analysis, violation of which can potentially introduce bias in MR analysis estimates. Conclusions. We present an overview of tools and methods to assess risk of bias/quality of evidence in MR analysis. As none of these methods has been tested and validated for general use, we do not provide recommendations on their use. Our findings should raise awareness about the importance of bias related to MR analysis and provide information that is useful for assessment of MR studies in the context of systematic reviews.

The impact of changing cigarette smoking habits and smoke-free legislation on orofacial cleft incidence in the United Kingdom: Evidence from two time-series studies.

Abstract: BACKGROUND Both active and passive cigarette smoking have previously been associated with orofacial cleft aetiology. We aimed to analyse the impact of declining active smoking prevalence and the implementation of smoke-free legislation on the incidence of children born with a cleft lip and/or palate within the United Kingdom. METHODS AND FINDINGS We conducted regression analysis using national administrative data in the United Kingdom between 2000-2018. The main outcome measure was orofacial cleft incidence, reported annually for England, Wales and Northern Ireland and separately for Scotland. First, we conducted an ecological study with longitudinal time-series analysis using smoking prevalence data for females over 16 years of age. Second, we used a natural experiment design with interrupted time-series analysis to assess the impact of smoke-free legislation. Over the study period, the annual incidence of orofacial cleft per 10,000 live births ranged from 14.2-16.2 in England, Wales and Northern Ireland and 13.4-18.8 in Scotland. The proportion of active smokers amongst females in the United Kingdom declined by 37% during the study period. Adjusted regression analysis did not show a correlation between the proportion of active smokers and orofacial cleft incidence in either dataset, although we were unable to exclude a modest effect of the magnitude seen in individual-level observational studies. The data in England, Wales and Northern Ireland suggested an 8% reduction in orofacial cleft incidence (RR 0.92, 95%CI 0.85 to 0.99; P = 0.024) following the implementation of smoke-free legislation. In Scotland, there was weak evidence for an increase in orofacial cleft incidence following smoke-free legislation (RR 1.16, 95%CI 0.94 to 1.44; P = 0.173). CONCLUSIONS These two ecological studies offer a novel insight into the influence of smoking in orofacial cleft aetiology, adding to the evidence base from individual-level studies. Our results suggest that smoke-free legislation may have reduced orofacial cleft incidence in England, Wales and Northern Ireland.

Philtral Height Discrepancy in Patients with Complete and Incomplete Cleft Lips + /-Palate - Results from a Single Nation Consecutive Cohort.

Abstract: INTRODUCTION The aim of unilateral cleft lip repair is to restore form and function, including symmetrisation of cleft and non-cleft philtral height. Expectation of best outcome is achieved in situations with minimal asymmetry and is assumed occurs most often in incomplete cleft lip only patients. We sought to investigate philtral height discrepancy (PHD) in children with unilateral cleft lip + /-palate from a single nation cohort. METHODS Review of prospectively collected PHD measurements taken at time of surgery for all children undergoing unilateral cleft lip repair in Scotland born Jan 2017-December 2020. Data was collected using Microsoft Excel and analysed using embedded statistical software. RESULTS 102 consecutive patients with unilateral lip involvement were identified from the national database. 94 had prospectively documented PHD (92.2%). The majority of patients had an isolated cleft lip (51.1%). Incomplete clefts presented more frequently (52.1%) than complete clefts (47.9%). Mean PHD for the whole cohort was 3.91mm (standard deviation 1.01mm, range 1-6mm). The difference in mean PHD (in-complete versus complete) was 1.1mm (3.4 vs. 4.5, p < 0.001). For lip only versus lip and palate the difference in mean PHD was 1.0mm (3.4 vs. 4.4, p < 0.001). CONCLUSIONS This single country consecutive cohort review of PHD in children undergoing unilateral cleft lip repair statistically supports the anecdote that patients with an incomplete cleft lip and isolated cleft lip have lesser asymmetry at presentation. This study presents a consecutive cohort with a greater range of PHD than has previously been reported in the literature.