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"Ramsay, Craig R."
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Methodology and reporting characteristics of studies using interrupted time series design in healthcare
by
Hudson, Jemma
,
Fielding, Shona
,
Ramsay, Craig R.
in
Data collection
,
Evaluation
,
Evidence-based medicine
2019
Background
Randomised controlled trials (RCTs) are considered the gold standard when evaluating the causal effects of healthcare interventions. When RCTs cannot be used (e.g. ethically difficult), the interrupted time series (ITS) design is a possible alternative. ITS is one of the strongest quasi-experimental designs. The aim of this methodological study was to describe how ITS designs were being used, the design characteristics, and reporting in the healthcare setting.
Methods
We searched MEDLINE for reports of ITS designs published in 2015 which had a minimum of two data points collected pre-intervention and one post-intervention. There was no restriction on participants, language of study, or type of outcome. Data were summarised using appropriate summary statistics.
Results
One hundred and sixteen studies were included in the study. Interventions evaluated were mainly programs 41 (35%) and policies 32 (28%). Data were usually collected at monthly intervals, 74 (64%). Of the 115 studies that reported an analysis, the most common method was segmented regression (78%), 55% considered autocorrelation, and only seven reported a sample size calculation. Estimation of intervention effects were reported as change in slope (84%) and change in level (70%) and 21% reported long-term change in levels.
Conclusions
This methodological study identified problems in the reporting of design features and results of ITS studies, and highlights the need for future work in the development of formal reporting guidelines and methodological work.
Journal Article
An Audit and Feedback Intervention for Reducing Antibiotic Prescribing in General Dental Practice: The RAPiD Cluster Randomised Controlled Trial
by
Clarkson, Jan E.
,
Ramsay, Craig R.
,
Newlands, Rumana
in
Analysis
,
Anti-Bacterial Agents - therapeutic use
,
Antibiotics
2016
Dentists prescribe approximately 10% of antibiotics dispensed in UK community pharmacies. Despite clear clinical guidance, dentists often prescribe antibiotics inappropriately. This cluster-randomised controlled trial used routinely collected National Health Service (NHS) dental prescribing and treatment claim data to compare the impact of individualised audit and feedback (A&F) interventions on dentists' antibiotic prescribing rates.
All 795 antibiotic prescribing NHS general dental practices in Scotland were included. Practices were randomised to the control (practices = 163; dentists = 567) or A&F intervention group (practices = 632; dentists = 1,999). A&F intervention practices were allocated to one of two A&F groups: (1) individualised graphical A&F comprising a line graph plotting an individual dentist's monthly antibiotic prescribing rate (practices = 316; dentists = 1,001); or (2) individualised graphical A&F plus a written behaviour change message synthesising and reiterating national guidance recommendations for dental antibiotic prescribing (practices = 316; dentists = 998). Intervention practices were also simultaneously randomised to receive A&F: (i) with or without a health board comparator comprising the addition of a line to the graphical A&F plotting the monthly antibiotic prescribing rate of all dentists in the health board; and (ii) delivered at 0 and 6 mo or at 0, 6, and 9 mo, giving a total of eight intervention groups. The primary outcome, measured by the trial statistician who was blinded to allocation, was the total number of antibiotic items dispensed per 100 NHS treatment claims over the 12 mo post-delivery of the baseline A&F. Primary outcome data was available for 152 control practices (dentists = 438) and 609 intervention practices (dentists = 1,550). At baseline, the number of antibiotic items prescribed per 100 NHS treatment claims was 8.3 in the control group and 8.5 in the intervention group. At follow-up, antibiotic prescribing had decreased by 0.4 antibiotic items per 100 NHS treatment claims in control practices and by 1.0 in intervention practices. This represents a significant reduction (-5.7%; 95% CI -10.2% to -1.1%; p = 0.01) in dentists' prescribing rate in the intervention group relative to the control group. Intervention subgroup analyses found a 6.1% reduction in the antibiotic prescribing rate of dentists who had received the written behaviour change message relative to dentists who had not (95% CI -10.4% to -1.9%; p = 0.01). There was no significant between-group difference in the prescribing rate of dentists who received a health board comparator relative to those who did not (-4.3%; 95% CI -8.6% to 0.1%; p = 0.06), nor between dentists who received A&F at 0 and 6 mo relative to those who received A&F at 0, 6, and 9 mo (0.02%; 95% CI -4.2% to 4.2%; p = 0.99). The key limitations relate to the use of routinely collected datasets which did not allow evaluation of any effects on inappropriate prescribing.
A&F derived from routinely collected datasets led to a significant reduction in the antibiotic prescribing rate of dentists.
Current Controlled Trials ISRCTN49204710.
Journal Article
Five-Year Outcomes of a Randomized Trial of Treatments for Varicose Veins
2019
In a randomized trial, 798 patients with varicose veins were assigned to undergo laser ablation, foam sclerotherapy, or surgery. At 5 years, disease-specific quality of life was better after laser ablation or surgery than after foam sclerotherapy, and cost-effectiveness analysis favored laser ablation.
Journal Article
A Randomized Trial Comparing Treatments for Varicose Veins
by
Ramsay, Craig R
,
Baker, Sara A
,
Francis, Jill
in
Ablation
,
Adult
,
Biological and medical sciences
2014
This trial of varicose-vein treatments showed no substantial differences in quality of life 6 months after ultrasound-guided foam sclerotherapy, endovenous laser ablation, or surgery, but disease-specific quality of life was slightly worse after foam treatment than after surgery.
Ultrasound-guided foam sclerotherapy and thermal ablation techniques such as endovenous laser ablation have become widely used alternatives to surgery for the treatment of varicose veins. Previous randomized trials and meta-analyses have shown these treatments to be effective in terms of short-term technical success and clinician-reported outcomes.
1
–
19
Clinical practice guidelines recommend the use of patient-reported quality of life to assess the outcomes of treatment of varicose veins.
20
Quality of life was a primary outcome measure in two small randomized trials that compared surgery and endovenous laser ablation,
5
,
9
but to our knowledge, it has not been assessed as a primary . . .
Journal Article
Developing a core outcome set for periodontal trials
by
Clarkson, Jan E.
,
Ricketts, David N. J.
,
Gillies, Katie
in
Biology and Life Sciences
,
Care and treatment
,
Clinical trials
2021
There is no agreement which outcomes should be measured when investigating interventions for periodontal diseases. It is difficult to compare or combine studies with different outcomes; resulting in research wastage and uncertainty for patients and healthcare professionals.
Develop a core outcome set (COS) relevant to key stakeholders for use in effectiveness trials investigating prevention and management of periodontal diseases.
Mixed method study involving literature review; online Delphi Study; and face-to-face consensus meeting.
Key stakeholders: patients, dentists, hygienist/therapists, periodontists, researchers.
The literature review identified 37 unique outcomes. Delphi round 1: 20 patients and 51 dental professional and researchers prioritised 25 and suggested an additional 11 outcomes. Delphi round 2: from the resulting 36 outcomes, 13 patients and 39 dental professionals and researchers prioritised 22 outcomes. A face-to-face consensus meeting was hosted in Dundee, Scotland by an independent chair. Eight patients and six dental professional and researchers participated. The final COS contains: Probing depths, Quality of life, Quantified levels of gingivitis, Quantified levels of plaque, Tooth loss.
Implementation of this COS will ensure the results of future effectiveness trials for periodontal diseases are more relevant to patients and dental professionals, reducing research wastage. This could reduce uncertainty for patients and dental professionals by ensuring the evidence used to inform their choices is meaningful to them. It could also strengthen the quality and certainty of the evidence about the relative effectiveness of interventions.
COMET Database: http://www.comet-initiative.org/studies/details/265?result=true.
Journal Article
Predictors of long-term intraocular pressure control after lens extraction in primary angle closure glaucoma: results from the EAGLE trial
by
Mitchell, William G
,
Ramsay, Craig R
,
Halawa, Omar
in
Cataract Extraction
,
Cataracts
,
Clinical science
2023
Background/aimsTo assess baseline ocular parameters in the prediction of long-term intraocular pressure (IOP) control after clear lens extraction (CLE) or laser peripheral iridotomy (LPI) in patients with primary angle closure (PAC) disease using data from the Effectiveness of Early Lens Extraction for the treatment of primary angle-closure glaucoma (EAGLE) tria.MethodsThis study is a secondary analysis of EAGLE data where we define the primary outcome of ‘good responders’ as those with IOP<21 mm Hg without requiring additional surgery and ‘optimal responders’ as those who in addition were medication free, at 36-month follow-up. Primary analysis was conducted using a multivariate logistic regression model to assess how randomised interventions and ocular parameters predict treatment response.ResultsA total of 369 patients (182 in CLE arm and 187 in LPI arm) completed the 36-month follow-up examination. After CLE, 90% met our predefined ‘good response’ criterion compared with 67% in the LPI arm, and 66% met ‘optimal response’ criterion compared with 18% in the LPI arm, with significantly longer drops/surgery-free survival time (p<0.05 for all). Patients randomised to CLE (OR=10.1 (6.1 to 16.8)), Chinese (OR=2.3 (1.3 to 3.9)), and those who had not previously used glaucoma drops (OR=2.8 (1.6 to 4.8)) were more likely to maintain long-term optimal IOP response over 36 months.ConclusionPatients with primary angle closure glaucoma/PAC are 10 times more likely to maintain drop-free good IOP control with initial CLE surgery than LPI. Non-Chinese ethnicity, higher baseline IOP and using glaucoma drops prior to randomisation are predictors of worse long-term IOP response.
Journal Article
Using re-randomisation designs to increase the efficiency and applicability of retention studies within trials: a case study
2023
Background
Poor retention in randomised trials can lead to serious consequences to their validity. Studies within trials (SWATs) are used to identify the most effective interventions to increase retention. Many interventions could be applied at any follow-up time point, but SWATs commonly assess interventions at a single time point, which can reduce efficiency.
Methods
The re-randomisation design allows participants to be re-enrolled and re-randomised whenever a new retention opportunity occurs (i.e. a new follow-up time point where the intervention could be applied). The main advantages are as follows: (a) it allows the estimation of an average effect across time points, thus increasing generalisability; (b) it can be more efficient than a parallel arm trial due to increased sample size; and (c) it allows subgroup analyses to estimate effectiveness at different time points. We present a case study where the re-randomisation design is used in a SWAT.
Results
In our case study, the host trial is a dental trial with two available follow-up points. The Sticker SWAT tests whether adding the trial logo’s sticker to the questionnaire’s envelope will result in a higher response rate compared with not adding the sticker. The primary outcome is the response rate to postal questionnaires. The re-randomisation design could double the available sample size compared to a parallel arm trial, resulting in the ability to detect an effect size around 28% smaller.
Conclusion
The re-randomisation design can increase the efficiency and generalisability of SWATs for trials with multiple follow-up time points.
Journal Article
Dentists’ perspectives on selective caries removal for the management of deep carious lesions in permanent teeth
by
Deery, Chris
,
Ramsay, Craig R.
,
El-Yousfi, Sarab
in
Adaptation
,
Adult
,
Attitude of Health Personnel
2025
Background
To explore the views of dentists participating in the Selective Caries Removal in Permanent Teeth (SCRiPT) randomised controlled clinical trial on selective caries removal versus complete or near complete caries removal for the management of deep carious lesions.
Methods
Nineteen semi-structured one-to-one telephone or online video interviews were conducted with dentists involved in SCRiPT, using an interview guide informed by the Theoretical Domains Framework (TDF). Data were initially analysed deductively using a framework informed by the TDF, and subsequently using reflexive thematic analysis.
Results
Three themes and 25 sub-themes were generated. Themes were ‘comfort using selective caries removal’, ‘potential value of SCRiPT’ and ‘challenges of subjectivity’. Sub-themes included six enablers and five barriers to the use of selective caries removal, as well as five contextual factors potentially impacting dentists’ decision-making. The SCRiPT trial was found to have potential value in terms of ‘overcoming uncertainty’, although perceived limitations were noted. The potential value of SCRiPT may depend on other factors, including the willingness of dentists to follow evidence from the trial (reflecting personal attributes and comfort with selective caries removal). The interviews also highlighted how caries removal is perceived as subjective and involves the application of clinical judgement to individual cases. General dental practitioners who are less comfortable with selective caries removal may not start to use this approach as defined within SCRiPT, particularly if there is a lack of strong evidence from the trial.
Conclusions
Dentists’ level of comfort with selective caries removal is multi-faceted and informed by contextual factors. SCRiPT has the potential to increase acceptance of selective caries removal, but the findings may not be interpreted in this way. Future work should further explore the concept of comfort with selective caries removal, using the thematic framework outlined here to inform the design of interview topic guides.
Trial registration
Trial registry: ISRCTN. Trial registration number: ISRCTN76503940. Date of Registration: 30.10.2019.
Journal Article
Expert Opinion on Laparoscopic Surgery for Colorectal Cancer Parallels Evidence from a Cumulative Meta-Analysis of Randomized Controlled Trials
by
Martel, Guillaume
,
Boushey, Robin P.
,
Ramsay, Craig R.
in
Acceptability
,
Accumulation
,
Cancer
2012
This study sought to synthesize survival outcomes from trials of laparoscopic and open colorectal cancer surgery, and to determine whether expert acceptance of this technology in the literature has parallel cumulative survival evidence.
A systematic review of randomized trials was conducted. The primary outcome was survival, and meta-analysis of time-to-event data was conducted. Expert opinion in the literature (published reviews, guidelines, and textbook chapters) on the acceptability of laparoscopic colorectal cancer was graded using a 7-point scale. Pooled survival data were correlated in time with accumulating expert opinion scores.
A total of 5,800 citations were screened. Of these, 39 publications pertaining to 23 individual trials were retained. As well, 414 reviews were included (28 guidelines, 30 textbook chapters, 20 systematic reviews, 336 narrative reviews). In total, 5,782 patients were randomized to laparoscopic (n = 3,031) and open (n = 2,751) colorectal surgery. Survival data were presented in 16 publications. Laparoscopic surgery was not inferior to open surgery in terms of overall survival (HR = 0.94, 95% CI 0.80, 1.09). Expert opinion in the literature pertaining to the oncologic acceptability of laparoscopic surgery for colon cancer correlated most closely with the publication of large RCTs in 2002-2004. Although increasingly accepted since 2006, laparoscopic surgery for rectal cancer remained controversial.
Laparoscopic surgery for colon cancer is non-inferior to open surgery in terms of overall survival, and has been so since 2004. The majority expert opinion in the literature has considered these two techniques to be equivalent since 2002-2004. Laparoscopic surgery for rectal cancer has been increasingly accepted since 2006, but remains controversial. Knowledge translation efforts in this field appear to have paralleled the accumulation of clinical trial evidence.
Journal Article
Simulating complex patient populations with hierarchical learning effects to support methods development for post-market surveillance
by
Koola, Jejo D.
,
Govindarajulu, Usha S.
,
Ssemaganda, Henry
in
Algorithms
,
Computer Simulation
,
Deep Learning
2023
Background
Validating new algorithms, such as methods to disentangle intrinsic treatment risk from risk associated with experiential learning of novel treatments, often requires knowing the ground truth for data characteristics under investigation. Since the ground truth is inaccessible in real world data, simulation studies using synthetic datasets that mimic complex clinical environments are essential. We describe and evaluate a generalizable framework for injecting hierarchical learning effects within a robust data generation process that incorporates the magnitude of intrinsic risk and accounts for known critical elements in clinical data relationships.
Methods
We present a multi-step data generating process with customizable options and flexible modules to support a variety of simulation requirements. Synthetic patients with nonlinear and correlated features are assigned to provider and institution case series. The probability of treatment and outcome assignment are associated with patient features based on user definitions. Risk due to experiential learning by providers and/or institutions when novel treatments are introduced is injected at various speeds and magnitudes. To further reflect real-world complexity, users can request missing values and omitted variables. We illustrate an implementation of our method in a case study using MIMIC-III data for reference patient feature distributions.
Results
Realized data characteristics in the simulated data reflected specified values. Apparent deviations in treatment effects and feature distributions, though not statistically significant, were most common in small datasets (n < 3000) and attributable to random noise and variability in estimating realized values in small samples. When learning effects were specified, synthetic datasets exhibited changes in the probability of an adverse outcomes as cases accrued for the treatment group impacted by learning and stable probabilities as cases accrued for the treatment group not affected by learning.
Conclusions
Our framework extends clinical data simulation techniques beyond generation of patient features to incorporate hierarchical learning effects. This enables the complex simulation studies required to develop and rigorously test algorithms developed to disentangle treatment safety signals from the effects of experiential learning. By supporting such efforts, this work can help identify training opportunities, avoid unwarranted restriction of access to medical advances, and hasten treatment improvements.
Journal Article