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Simon Gates

Publications and source records attributed to Simon Gates.

9 recordsLinked to original sources
PubMed2026

Chemoradiotherapy versus short-course radiotherapy for response-adapted organ preservation in early-stage and intermediate-stage rectal cancer (STAR-TREC): 12-month results of an international, multicentre, open-label, parallel-group, randomised, phase 2/3 trial.

BACKGROUND: Total mesorectal excision (TME) is the standard treatment for most early-stage and intermediate-stage rectal cancer but can cause substantial perioperative morbidity, functional impairment, and reduced quality of life. We assessed whether long-course chemoradiotherapy (LCCRT) or short-course radiotherapy (SCRT) could increase organ preservation and reduce surgery, toxicity, and quality-of-life harms without compromising oncological outcomes. METHODS: STAR-TREC is an international, multicentre, open-label, parallel-group, randomised, phase 2/3 trial in five European countries. Eligible patients were aged 16 years or older in the UK or aged 18 years or older elsewhere, had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and rectal adenocarcinoma (≤40 mm staged as mrT1-T3bN0). In phase 2, participants were randomly assigned (1:1:1) to LCCRT-based organ preservation (LCCRT-OP; 50 Gy in 25 fractions plus oral capecitabine 825 mg/m2 twice daily), SCRT-based organ preservation (SCRT-OP; 25 Gy in five fractions), or primary TME. Phase 2 assessed feasibility, with recruitment at months 12 and 24 as the primary endpoint and feasibility thresholds of four or more and six or more randomisations per month, respectively. Phase 3 adopted a partially randomised patient-preference design, allowing participants to choose either organ preservation or TME. Participants that chose organ preservation were randomly assigned (1:1) to receive LCCRT-OP or SCRT-OP using centralised, computer-generated assignment, with stratification by country and MRI T category (≤T3a vs T3b) using minimisation. The phase 3 primary endpoint was organ-preservation 30 months after treatment initiation, defined as absence of TME, stoma, or local recurrence, which was assessed in the modified intention-to-treat population, which included participants in phase 2 and phase 3. After a planned interim analysis of unmasked phase 2 data, the trial steering committee and independent data monitoring committee recommended reporting a 12-month, modified intention-to-treat analysis of implementation outcomes for participants recruited before Aug 8, 2023. This study is registered with ISRCTN (14240288) and is closed. FINDINGS: Between June 14, 2017, and April 8, 2024, 503 participants were enrolled at 37 sites. Phase 2 enrolled 120 participants, with recruitment rates of three and six participants per month at months 12 and 24, respectively. Overall, 12-month TME-free survival was 60% (47 of 78 participants). After phase 3 recruitment ended, interim analysis of unmasked phase 2 data showed an early TME-free survival benefit with LCCRT versus SCRT (12-month median TME-free survival not reached [95% CI not reached-not reached] vs 7·6 months [95% CI 6·4-not reached]; hazard ratio [HR] 3·7 [95% CI 1·7-8·0]; posterior probability of superiority >99·5%). The trial steering committee and independent data monitoring committee therefore recommended expanded analysis of 426 participants recruited before Aug 8, 2023: 120 from phase 2 and 306 from phase 3. 17 participants withdrew before treatment, leaving 409 in the modified intention-to-treat population: 163 allocated to LCCRT, 168 to SCRT, and 78 to primary TME. 116 (28%) participants were female and 293 (72%) were male. Among participants who opted for organ preservation, 12-month TME-free survival was 78·5% (95% CI 72·4-85·1) with LCCRT and 60·6% (53·6-68·4) with SCRT (HR 1·90 [95% CI 1·29-2·81]). The most common grade 3-4 serious adverse events were gastrointestinal disorders (four [2%] with LCCRT vs six [4%] with SCRT vs six [8%] with TME) and procedural complications (three [2%] with LCCRT vs five [3%] with SCRT vs five [6%] with TME). One participant allocated to primary TME died after an anastomotic leak. INTERPRETATION: These early results support a response-adapted organ-preservation approach, with LCCRT appearing more effective than SCRT at 12 months. Organ-preservation might also reduce treatment-related toxicity compared with primary TME. Longer follow-up is needed for the prespecified 30-month endpoint and definitive functional and oncological outcomes. FUNDING: Cancer Research UK, Stand Up to Cancer, Dutch Cancer Society, Danish Cancer Society, Kom Op Tegen Kanker, Cancerfonden, ALF Region Stockholm, RCC Region Stockholm.

Humans↗
PubMed2006

Maximising response to postal questionnaires--a systematic review of randomised trials in health research.

BACKGROUND: Postal self-completion questionnaires offer one of the least expensive modes of collecting patient based outcomes in health care research. The purpose of this review is to assess the efficacy of methods of increasing response to postal questionnaires in health care studies on patient populations. METHODS: The following databases were searched: Medline, Embase, CENTRAL, CDSR, PsycINFO, NRR and ZETOC. Reference lists of relevant reviews and relevant journals were hand searched. Inclusion criteria were randomised trials of strategies to improve questionnaire response in health care research on patient populations. Response rate was defined as the percentage of questionnaires returned after all follow-up efforts. Study quality was assessed by two independent reviewers. The Mantel-Haenszel method was used to calculate the pooled odds ratios. RESULTS: Thirteen studies reporting fifteen trials were included. Implementation of reminder letters and telephone contact had the most significant effect on response rates (odds ratio 3.7, 95% confidence interval 2.30 to 5.97 p = or <0.00001). Shorter questionnaires also improved response rates to a lesser degree (odds ratio 1.4, 95% confidence interval 1.19 to 1.54). No evidence was found that incentives, re-ordering of questions or including an information brochure with the questionnaire confer any additional advantage. CONCLUSION: Implementing repeat mailing strategies and/or telephone reminders may improve response to postal questionnaires in health care research. Making the questionnaire shorter may also improve response rates. There is a lack of evidence to suggest that incentives are useful. In the context of health care research all strategies to improve response to postal questionnaires require further evaluation.

Correspondence as Topic↗
PubMed2005

Effect on survey response rate of hand written versus printed signature on a covering letter: randomised controlled trial [ISRCTN67566265].

BACKGROUND: It is important that response rates to postal surveys are as high as possible to ensure that the results are representative and to maximise statistical power. Previous research has suggested that any personalisation of approach helps to improve the response rate. This experiment tested whether personalising questionnaires by hand signing the covering letter improved the response rate compared with a non-personalised group where the investigator's signature on the covering letter was scanned into the document and printed. METHODS: Randomised controlled trial. Questionnaires about surgical techniques of caesarean section were mailed to 3,799 Members and Fellows of the Royal College of Obstetricians and Gynaecologists resident in the UK. Individuals were randomly allocated to receive a covering letter with either a computer printed signature or a hand written signature. Two reminders were sent to non-respondents. The outcome measures were the proportion of questionnaires returned and their time to return. RESULTS: The response rate was 79.1% (1506/1905) in the hand-signed group and 78.4% (1484/1894) in the scanned and printed signature group. There was no detectable difference between the groups in response rate or time taken to respond. CONCLUSION: No advantage was detected to hand signing the covering letter accompanying a postal questionnaire to health professionals.

Adult↗
PubMed2004

Thromboprophylaxis and pregnancy: two randomized controlled pilot trials that used low-molecular-weight heparin.

OBJECTIVE: The purpose of this study was to conduct pilot studies for large randomized controlled trials to compare low-molecular-weight heparin with placebo for antenatal thromboprophylaxis (trial 1), and for thromboprophylaxis after cesarean delivery (trial 2). STUDY DESIGN: Multicenter randomized controlled trials (trial 1, 23 units; trial 2, 8 units) were conducted. Pregnant women at increased risk for thromboembolic disease were eligible for trial 1; women who underwent cesarean delivery were eligible for trial 2. The interventions were once daily injections of low-molecular-weight heparin or placebo. Primary outcomes were as follows: trial 1, confirmed symptomatic thromboembolic events and symptomatic osteoporotic fractures; trial 2, confirmed symptomatic thromboembolic events and wound complications. RESULTS: Sixteen women were recruited for trial 1; 1 woman in the placebo group had a symptomatic thromboembolic event. One hundred forty-one women were recruited for trial 2; 1 woman in the low molecular weight heparin group had a symptomatic thromboembolic event. CONCLUSION: Poor recruitment indicates that large-scale trials using these designs would be difficult. Collection of data on the number of women that are eligible and the reasons for nonrecruitment in future trials of these interventions would allow a better understanding of the reasons for poor recruitment.

Adult↗
PubMed2004

How should randomised trials including multiple pregnancies be analysed?

OBJECTIVE: To compare the effects of four methods of analysis on the results of randomised controlled trials that recruit women with multiple pregnancies and measure outcomes on their babies. DESIGN: Analysis of one real and two simulated data sets. SETTING: Secondary analysis of perinatal randomised controlled trials. POPULATION: Randomised controlled trials including women with multiple pregnancies. METHODS: The analytical methods compared were (a) assuming independence among babies, (b) analysing outcomes per women, counting a woman as having an outcome if any of her babies had it (equivalent to selecting the worst outcome among any of a woman's babies), (c) randomly selecting one baby from each set of multiples for inclusion in the analysis, (d) adjustment of the analysis to take account of non-independence of babies from multiple pregnancies, using methods developed for analysis of cluster randomised trials. MAIN OUTCOME MEASURES: Odds ratios for trials' main outcomes. RESULTS: Results from application of cluster trial methods were similar to those from assuming independence among babies, but with slightly wider confidence intervals, reflecting the reduced effective sample size caused by non-independence between babies from the same pregnancy. Results were more variable using the other two methods, and in some cases, departed markedly from the results of the cluster trial methods. CONCLUSIONS: Cluster trial methods provide a simple way of adjusting the analysis to take account of non-independence between babies from the same pregnancy. Random selection and analysis by pregnancy (methods (b) and (c)) have disadvantages and do not report outcomes for all of the babies in the trial. This may cause problems with incorporating trials analysed using these methods into systematic reviews.

Cluster Analysis↗
PubMed2003

Admission cardiotocography: a randomised controlled trial.

BACKGROUND: Admission cardiotocography is widely used to identify pregnancies that might benefit from continuous electronic fetal monitoring in labour. We aimed to compare the effect on neonatal outcome of admission cardiotocography versus intermittent auscultation of the fetal heart rate. METHODS: 8580 women admitted to the delivery ward of a Dublin teaching hospital who were at low risk of fetal distress in labour were randomly assigned admission cardiotocography (20 min) or the unit's usual care (intermittent auscultation only, with continuous cardiotocography only if clinically indicated). The primary outcome was moderate to severe neonatal morbidity, or perinatal mortality in the absence of a major congenital malformation. Analyses were by intention to treat. FINDINGS: 44 (1.0%) women assigned admission cardiotocography did not undergo the procedure; 15 (0.4%) assigned usual care had admission cardiotocography. The primary endpoint occurred in 56 (1.3%) of 4298 women assigned admission cardiotocography and 55 (1.3%) of 4282 in the usual-care group (relative risk 1.01; 95% CI 0.70-1.47). Other indices of neonatal morbidity also showed no differences. Despite an increase in use of continuous cardiotocography (1.39; 1.33-1.45) and fetal blood sampling (1.30; 1.14-1.47) with admission cardiotocography, there were no significant differences in the rates of caesarean delivery (1.13; 0.92-1.40), instrumental delivery (1.03; 0.92-1.16), or episiotomy (1.06; 0.99-1.13). INTERPRETATION: Routine use of cardiotocography for 20 min on admission to the delivery ward does not improve neonatal outcome. No significant increase in operative delivery was apparent, probably because of liberal use of fetal blood sampling.

Apgar Score↗
PubMed2002

Surgical techniques used during caesarean section operations: results of a national survey of practice in the UK.

OBJECTIVE: To determine what surgical techniques are used by obstetricians in the UK for elective and emergency caesarean section operations. STUDY DESIGN: A postal questionnaire to all members and fellows of the Royal College of Obstetricians and Gynaecologists (RCOG) resident in the UK, requesting information about the use of surgical techniques and antibiotic and anticoagulant prophylaxis for elective and emergency caesarean sections. RESULTS: The response rate was 78.7%. A range of techniques was used for all procedures in caesarean section operations. Only a few techniques were used by more than 80% of obstetricians, including double layer closure of the uterus, use of prophylactic antibiotics and Pfannenstiel abdominal entry (for elective caesarean sections). There were few large differences in practice between elective and emergency caesarean sections. In emergency operations, more obstetricians use the Joel-Cohen method of abdominal entry (32.7 versus 16%) and more usually use prophylactic antibiotics and heparin (93.2 versus 85.4% and 45.8 versus 32.9%, respectively). CONCLUSIONS: There was wide variation in the surgical techniques used by obstetricians for caesarean section operations. There is an urgent need for future research to evaluate many aspects of caesarean section operations on substantive short- and long-term outcomes.

Anti-Bacterial Agents↗