Why would young people donate blood? A survey‐based questionnaire study

Background and Objectives   Different issues associated with blood donation among young donors were studied, towards building a large and consistent blood donor base.
Methods   Data were collected from 221/285 donors in drives conducted among military personnel (response rate of 78%), through a self-administered questionnaire tailored to review knowledge, beliefs, attitudes and habits regarding blood and general donations. Data were then further analysed using a multivariate model.
Results   The most significant factors related to blood donation were the donors' perception of approval from a superior (the commander's request to donate blood) and the participant's military rank or position ( P  < 0·0001 and P  = 0·0019, respectively). Experienced blood donors comprised 71·9% of all donors and more donations were noted among men ( P  = 0·0013).
Conclusions   The important role of a significant superior, and his or her personal involvement in the blood drive organization was elucidated. Various other factors, previously found to be related to readiness or reluctance to donate blood, were insignificant among the studied population. Our finding may assist blood centres in optimizing their efforts in recruiting and retention of young donors.     

A prospective study of colonoscopy practice in the UK today: are we adequately prepared for national colorectal cancer screening tomorrow?

AIM: To study the availability and quality of adult and paediatric colonoscopy in three National Health Service (NHS) regions. METHOD: A prospective four month study of colonoscopies in North East Thames, West Midlands, and East Anglia. PATIENTS: Subjects undergoing colonoscopy in 68 endoscopy units. RESULTS: A total of 9223 colonoscopies were studied. The mean number of colonoscopies performed over the four month period was 142 in district general hospitals and 213 in teaching hospitals. Intravenous sedation was administered in 94.6% of procedures, but 2.2% and 11.4% of "at risk" patients did not have continuous venous access or did not receive supplemental oxygen, respectively. Caecal intubation was recorded in 76.9% of procedures but the adjusted caecal intubation rate was only 56.9%. Reasons for failing to reach the caecum included patient discomfort (34.7%), looping (29.7%), and poor bowel preparation (19.6%). A normal colonoscopy was reported in 42.1%. The most common diagnosis was polyps (22.5%) followed by diverticular disease (14.9%). Inflammatory bowel disease was recorded in 13.9% and carcinoma in 3.8%. Only half of the patients remembered being told of possible adverse events prior to the procedure. Rectal bleeding requiring admission following colonoscopy was reported in six patients. The overall perforation rate was 1:769 and colonoscopy was considered a possible factor in six deaths occurring within 30 days of the procedure. Only 17.0% of colonoscopists had received supervised training for their first 100 colonoscopies and only 39.3% had attended a training course. CONCLUSION: There is serious under provision of colonoscopy service in most NHS hospitals. Endoscopy sedation guidelines are not always adhered to and there is a wide variation in practice between units. Colonoscopy is often incomplete and does not achieve the target 90% caecal intubation rate. Serious complications of colonoscopy were comparable with previous studies. Training in colonoscopy is often inadequate and improved practice should result from better training.     

A population‐based audit for diagnosing colorectal cancer

Background: Knowledge of the diagnostic work‐up of colorectal cancer is a prerequisite to improve its quality. Family history is one of few known risk factors of the disease and it is therefore important to investigate to what extent this factor is used in routine management. Methods: Copies of records from all health‐care suppliers visited during diagnostic work‐up were requested for 227/235 (97%) patients with recently diagnosed colorectal cancer in the county of Västmanland during 1998–99. A first consultation was identified and records and all diagnostic measures related to the initial consultation were scrutinized. A family history of colorectal cancer was known for 179 patients. Results: Most of the patients, 107 (66%) colon and 57 (86%) rectal cancer patients, had consulted with a general practitioner. The median diagnostic work‐up time was 42 days (IQ 12–110) for colon and 23 days (IQ 0–49) for rectal cancer. A double‐contrast barium enema was the most commonly used diagnostic method for colon cancer. Family history was documented at the first consultation in 2/179 (1%) cases. In patients with right‐sided cancer, median diagnostic work‐up time was 53 days in patients with a positive result of faecal occult blood test (FOBT) as compared with 448 in patients with a negative result (P?Conclusion: Primary care is the key actor in diagnosing rectal cancer. The restricted capacity for X‐ray is one of the main obstacles in detection of colon cancer. Family history is rarely documented during diagnostic work‐up of colorectal cancer. The benefit of using FOBT in symptomatic patients is questioned.     

Complex hepato-pancreato-biliary caseload during general surgery residency training: are we adequately training the next generation?

BackgroundInformation on procedure volume of graduating chief residents (GCRs) for hepato-pancreato-biliary(HPB) surgical procedures may inform assessments of resident training. This study sought to characterize trends in operative volumes over a 19-year period to define the degree to which general surgery residents gain exposure to HPB procedures during training.MethodsThe ACGME was queried for all HPB operations performed by GCR between 2000-2018. Total procedures as well as means and fold change was calculated and reported for each year.ResultsBetween 2000–2018, the number of general surgery residency programs varied between 240 and 254. A total of 411,383 HPB procedures (36.2% liver, 42.8% pancreas, 21% complex biliary) were performed by 22,229 GCR. Each year of the study, GCR had similar mean number total procedures:liver 7.4, pancreas 8.7, and complex biliary 4.4. For liver procedures there was no difference in the fold change over time, however for pancreas there was an increase in the fold change from 2.25 to 3.25.ConclusionMost GCRs are graduating with a low number of HPB procedures and trends suggesting a decrease in the mean number of procedures per GCR and an increasing variability among residents.     

Are prophylactic antibiotics necessary for urodynamic study?

The aim of this study was to assess the efficacy of prophylactic fosfomycin tromethamine (FT) and ciprofloxacin in preventing bacteriuria caused by urodynamic studies (UDS). A total of 426 adult patients presenting for UDS were enrolled the study. A midstream urine sample was taken 72 hours before and 5 days after the procedure. All patients underwent a standard UDS. The 411 patients who had sterile urine before intervention were included in the study. Patients were randomized into three groups. Group1 received no prophylaxis (n = 133), Group 2 (n = 141) received oral ciprofloxacin (500 mg) 1 hour before the procedure, and Group 3 (n = 137) received a single dose of FT approximately 12 hours before the procedure. Bacteriuria was evaluated for each group. Bacteriuria was detected in 3 (2.3%), 6 (4.3%) and 3 patients (1.6%) in Group 1, Group 2, and Group 3, respectively. The most common identified microorganism was Escherichia coli (E coli) in 6 patients (50%). Among the E coli group, extended spectrum beta-lactamase producing E coli was seen in 2 patients (33.3%). Univariate analysis demonstrated that a history of urogenital operation (p < 0.01) and female gender (p < 0.01) were significant risk factors for bacteriuria. On multiple logistic regression analysis, the past urogenital operation history was the only significant independent risk factor for significant bacteriuria after UDS (OR = 14, 95% CI = 1.82–23.8, p = 0.01). The prevalence of bacteriuria after UDS was relatively low in the current study population. Therefore, for most patients, it may be unnecessary to use preventive prophylactic antibiotics. However, our results suggest that in patients with a previous history of urologic surgery, the risk for significant bacteriuria is increased and the use of prophylaxis should be considered.     

Metabolic syndrome: A clinic based rural study – Are women at high risk?

BackgroundReports of urban based studies suggest an increase in the prevalence of MS worldwide along with diabetes, hypertension and atherogenic dyslipidemia. The supporting rural based studies on MS are few and prevalence of MS among women is underestimated. In this prospective study we have evaluated the clinic prevalence of metabolic syndrome among rural Indian population with special emphasis on prevalence in women.Research design and method2329 patients attending to diabetic centre were evaluated for the markers of MS. Anthropometric measurements, clinical assessment, capillary blood glucose and lipid profile (TC, HDL-C, TG, LDL-C, VLDL-C) were done and classified as per NCEP ATP III and NCEP ATP III modified for Asian guidelines. We compared the prevalence of MS between males and females for statistical significance by SPSS 16.0 statistical software. The level of significance was kept at <0.05.ResultsThe Clinic prevalence of metabolic syndrome was 61.74% with 57.59% males and 69.66% females as per NCEP ATP III guidelines. 73.85% of the study population had MS, with 68.85% males and 83.39% females had MS as per modified Asian criteria. We could get a statistically significant variation between males and females in FBS, PPBS, SBP, DBP, TC, HDL-C, TG, LDL-C, VLDL-C, TC/HDL, LDL/HDL, BMI, W/H ratio and W/S ratio.ConclusionPrevalence MS is increasing at an epidemic proportion bringing with it micro and macro vascular complications. Women are more prone to develop MS in rural population than the men and there is a statistically significant variation in the biochemical and anthropometric parameters. This is an era of ‘gender equality’; here we see women over taking men in metabolic syndrome and its complications.     

A role for exercise after bariatric surgery?

Obesity predisposes an individual to develop numerous comorbidities, including type 2 diabetes, and represents a major healthcare issue in many countries worldwide. Bariatric surgery can be an effective treatment option, resulting in profound weight loss and improvements in metabolic health; however, not all patients achieve similar weight loss or metabolic improvements. Exercise is an excellent way to improve health, with well‐characterized physiological and psychological benefits. In the present paper we review the evidence to determine whether there may be a role for exercise as a complementary adjunct therapy to bariatric surgery. Objectively measured physical activity data indicate that most patients who undergo bariatric surgery do not exercise enough to reap the health benefits of exercise. While there is a dearth of data on the effects of exercise on weight loss and weight loss maintenance after surgery, evidence from studies of caloric restriction and exercise suggest that similar adjunctive benefits may be extended to patients who perform exercise after bariatric surgery. Recent evidence from exercise interventions after bariatric surgery suggests that exercise may provide further improvements in metabolic health compared with surgery‐induced weight loss alone. Additional randomized controlled exercise trials are now needed as the next step to more clearly define the potential for exercise to provide additional health benefits after bariatric surgery. This valuable evidence will inform clinical practice regarding much‐needed guidelines for exercise after bariatric surgery.     

A general construction for parallelizing Metropolis?Hastings algorithms

Markov chain Monte Carlo methods (MCMC) are essential tools for solving many modern-day statistical and computational problems; however, a major limitation is the inherently sequential nature of these algorithms. In this paper, we propose a natural generalization of the Metropolis−Hastings algorithm that allows for parallelizing a single chain using existing MCMC methods. We do so by proposing multiple points in parallel, then constructing and sampling from a finite-state Markov chain on the proposed points such that the overall procedure has the correct target density as its stationary distribution. Our approach is generally applicable and straightforward to implement. We demonstrate how this construction may be used to greatly increase the computational speed and statistical efficiency of a variety of existing MCMC methods, including Metropolis-Adjusted Langevin Algorithms and Adaptive MCMC. Furthermore, we show how it allows for a principled way of using every integration step within Hamiltonian Monte Carlo methods; our approach increases robustness to the choice of algorithmic parameters and results in increased accuracy of Monte Carlo estimates with little extra computational cost.Since its introduction in the 1970s, the Metropolis−Hastings algorithm has revolutionized computational statistics (1). The ability to draw samples from an arbitrary probability distribution, π(X), known only up to a constant, by constructing a Markov chain that converges to the correct stationary distribution has enabled the practical application of Bayesian inference for modeling a huge variety of scientific phenomena, and has resulted in Metropolis−Hastings being noted as one of the top 10 most important algorithms from the 20th century (2). Despite regular increases in available computing power, Markov chain Monte Carlo (MCMC) algorithms can still be computationally very expensive; many thousands of iterations may be necessary to obtain low-variance estimates of the required quantities with an oftentimes complex statistical model being evaluated for each set of proposed parameters. Furthermore, many Metropolis−Hastings algorithms are severely limited by their inherently sequential nature.Many approaches have been proposed for improving the statistical efficiency of MCMC, and although such algorithms are guaranteed to converge asymptotically to the stationary distribution, their performance over a finite number of iterations can vary hugely. Much research effort has therefore focused on developing transition kernels that enable moves to be proposed far from the current point and subsequently accepted with high probability, taking into account, for example, the correlation structure of the parameter space (3, 4), or by using Hamiltonian dynamics (5) or diffusion processes (6). A recent investigation into proposal kernels suggests that more exotic distributions, such as the Bactrian kernel, might also be used to increase the statistical efficiency of MCMC algorithms (7). The efficient exploration of high-dimensional and multimodal distributions is hugely challenging and provides the motivation for many further methods (8).Computational efficiency of MCMC algorithms is another important issue. Approaches have been suggested for making use of the increasingly low-cost parallelism that is available in modern-day computing, with the most straightforward based on running multiple Markov chains simultaneously (9). These may explore the same distribution, or some product of related distributions, as in parallel tempering (10). Furthermore, the locations of other chains may additionally be used to guide the proposal mechanism (11). More recent work combines the use of multiple chains with adaptive MCMC in an attempt to use these multiple sources of information to learn an appropriate proposal distribution (12, 13). Sometimes, specific MCMC algorithms are directly amenable to parallelization, such as independent Metropolis−Hastings (14) or slice sampling (15), as indeed are some statistical models via careful reparameterization (16) or implementation on specialist hardware, such as graphics processing units (GPUs) (17, 18); however, these approaches are often problem specific and not generally applicable. For problems involving large amounts of data, parallelization may in some cases also be possible by partitioning the data and analyzing each subset using standard MCMC methods simultaneously on multiple machines (19). The individual Markov chains in these methods, however, are all based on the standard sequential Metropolis−Hastings algorithm.The idea of parallelizing Metropolis−Hastings using multiple proposals has been investigated previously; however, the main shortcoming of such attempts has been their lack of computational efficiency. Algorithms such as Multiple Try Metropolis (20), Ensemble MCMC (21), and “prefetching” approaches (22, 23) all allow the computation of multiple proposals or future proposed paths in parallel, although only one proposal or path is subsequently accepted by the Markov chain, resulting in wasted computation of the remaining points. Another class of approaches involves incorporating rejected states into the Monte Carlo estimator with an appropriate weighting, such that the resulting estimate is still unbiased. An overview of such approaches is given by Frenkel (24). In particular, the work presented by Tjelmeland (25) makes use of multiple rejected states at each iteration and is related to the ideas presented here, although recent investigations suggest that including all rejected proposals may in fact sometimes result in a Monte Carlo estimate with asymptotically larger variance than using only accepted states (26).In this paper, we present a generalization of Metropolis−Hastings that may be used to parallelize a wide variety of existing MCMC algorithms, including most of those mentioned previously, from simple random-walk Metropolis to more recent Langevin-based algorithms, defined either on Euclidean or Riemannian spaces, and Adaptive MCMC. The approach we propose is highly scalable and may offer a couple of magnitudes improvement in time-normalized efficiency over existing algorithms. The approach offers additional practical benefit for Hamiltonian Monte Carlo (HMC) methods, by improving robustness to the choice of tuning parameters and providing a principled way of making use of the intermediate integration steps that are calculated at every iteration.     

Are diagnostic criteria for general joint hypermobility and benign joint hypermobility syndrome based on reproducible and valid tests? A review of the literature

OBJECTIVE: In this review we focus on current knowledge of the reliability of tests and diagnostic criteria for generalized joint hypermobility (GJH) and benign joint hypermobility syndrome (BJHS). METHODS: Currently, The British Society of Rheumatology recommends the Beighton scoring system. With this approach, GJH is judged present when 4 or more of 9 tests are positive. Curiously, only one inter/intrarater reproducibility study is available and it uses a cutoff level of 6, rather than the Beighton-recommended 4 positive tests. RESULTS: Using a 6 cut level, intra- and interobserver kappa scores were 0.75 and 0.78, respectively. Beighton scoring recommendations have been correlated with a global joint mobility index as well as with 2 other scoring systems, the Carter and Wilkinson, and the Rotès-Quérol. All illustrate high concurrent validity with one another. For the recently proposed Brighton criteria diagnosing BJHS no reproducibility studies exist. In the latter, the recommendations reflect high nosographic sensitivity and specificity while predictive values for positive test scores are poor. CONCLUSION: In general, the reproducibility of the various tests seems to be good, especially when performed by experienced rheumatologists.     

Are financial incentives for breastfeeding feasible in the UK? A mixed methods field study

BackgroundThe UK has one of the lowest breastfeeding rates (duration and exclusivity) in the world. Moreover, breastfeeding is strongly socially patterned, with young women in areas of high deprivation being less likely to breastfeed than women in areas of low deprivation. This study tested the feasibility of a financial incentive intervention to increase breastfeeding in areas with 6–8 week breastfeeding rates of 40% or less.MethodsThe intervention was the offer of a structured financial incentive scheme to women with babies aged up to 6 months old. If women were breastfeeding their baby, they could claim vouchers, at five different timepoints—ie, when their baby reached 2 days, 10 days, 6 weeks, 3 months, and 6 months old. Breastfeeding was verified by signed statements from the mother and health-care professional. Vouchers were for supermarkets and high street shops, to the value of £40, up to a maximum of £200. Starting in November, 2013, the scheme was offered to women with babies born during a 16-week period resident in three neighbourhoods in Derbyshire and South Yorkshire, UK, all of whom had historically persistent low 6–8 week breastfeeding rates, ranging from 21% to 29%. The feasibility (acceptability and deliverability) of the incentive scheme and the study design to key stakeholder groups was assessed with quantitative and qualitative methods, in advance of undertaking a full randomised controlled trial. 36 health-care providers and 18 women gave semi-structured interviews.FindingsRelevant approvals for the study were obtained. Women learnt about the scheme from their midwife or the media (print, radio, social media), or both. Of a total of 108 women eligible for the scheme, 58 (53·7%) joined the scheme, 48 (44·4%) claimed 2-day vouchers, 45 (41·7%) claimed 10-day vouchers, and 37 (34·3%) claimed 6–8 week vouchers. 3-month and 6-month data are still accruing. 53 health-care providers cosigned claim forms. Satisfaction with the scheme (including the method used to verify breastfeeding) was high among both mothers and health-care staff participating in the scheme.InterpretationThe scheme was both deliverable and acceptable to mothers and health-care staff in this field study. The scheme was extended (and will continue until at least December, 2014) in all three areas. A randomised controlled trial testing the effectiveness of the scheme is now planned.FundingMedical Research Council National Prevention Research Initiative (MR/J000434/1).     

Are multiple sinus cultures necessary during sinus surgery for chronic rhinosinusitis?

Background

Multiple cultures are commonly obtained from different sinuses where purulence is encountered during endoscopic sinus surgery (ESS). This brings into question the utility and necessity of obtaining multiple cultures. The purpose of this study was to evaluate if multiple cultures obtained during a single case is informative in finding additional pathogens or if it is a redundant, cost‐increasing practice. We hypothesized that multiple sinus cultures are necessary to identify the pathogens responsible for an individual's sinus disease. We seek to add information on the utility of performing multiple sinus cultures from a patient care and a health economics standpoint.

Methods

This study was a retrospective review of a single rhinologist's surgical database from 2008 to 2016. Patients that underwent ESS for chronic rhinosinusitis (CRS) and had multiple cultures obtained during surgery were included. Culture difference was recorded as a discrepancy of an infectious pathogen between cultures.

Results

We identified 231 patients with multiple sinus cultures. Of those, 39.4% had a difference of pathogens noted on culture between different sinuses. Only 5% of the cohort received clinically relevant benefit from the second culture obtained in regard to a change in antibiotics.

Conclusion

In this retrospective review we showed that, for the practitioner who obtains sinus cultures intraoperatively, limiting this practice to a single culture rather than multiple is cost‐effective and sufficient for identifying the pathogen to be treated. This study, and the resultant change in practice, has the potential to reduce healthcare costs associated with the surgical care of the patient with CRS.

     

Are treatments for vasovagal syncope effective? A meta-analysis

Background

Therapies used to treat vaso-vagal syncope (VVS) recurrence have not been proven effective in single studies.

Methods

Comprehensive search of PubMed, EMBASE and Cochrane Central databases of published trials was done. Randomized or non-randomized studies, comparing the intervention of interest to control group(s), with the endpoint of spontaneous recurrence or syncope on head-up tilt test, were included. Data were extracted on an intention-to-treat basis. Study heterogeneity was analyzed by Cochran's Q statistics. A random-effect analysis was used.

Results

α-adrenergic agonists were found effective (n = 400, OR 0.19, CI 0.06–0.62, p < 0.05) in preventing VVS recurrence. β-blockers were not found to be effective when only randomized studies comparing β-blockers to non-pharmacologic agents were assessed (9 studies, n = 583, OR 0.48, CI 0.22–1.04, p = 0.06). Tilt-training had no effect when only randomized studies were considered (4 studies, n = 298, OR 0.47, CI 0.21–1.05, p = 0.07). Selective serotonin reuptake inhibitors were found effective (n = 131, OR 0.28, CI 0.10–0.74, p < 0.05), though the analysis contained only 2 studies. Pacemakers were found effective in preventing syncope recurrence when all studies were analyzed (n = 463, OR 0.13, CI 0.05–0.36, p < 0.05). However, studies comparing active pacemaker to sensing mode only did not show benefit (3 studies, n = 162, OR 0.45, CI 0.09–2.14, p = 0.32).

Conclusions

This meta-analysis highlights the totality of evidence for commonly used medications used to treat VVS, and the requirement for larger, double-blind, placebo controlled trials with longer follow-up.     

Are script concordance tests suitable for the assessment of undergraduate students? A multicenter comparative study

IntroductionScript concordance tests (SCTs) have been developed to assess clinical reasoning in uncertain situations. Their reliability for the evaluation of undergraduate medical students has not been evaluated.MethodsTwenty internal medicine SCT cases were implemented in undergraduate students of two programs. The results obtained on the SCTs were compared to those obtained by the same students on clinical-based classical multiple-choice questions (MCQs).ResultsA total of 551/883 students (62%) answered the SCTs. The mean aggregate score (based on a total 20 points) was 11.54 (3.29). The success rate and mean score for each question did not differ depending on the modal response but the discrimination rate did. The results obtained by the students on the SCT test correlated with their scores on the MCQ tests. Among students, 446/517 (86%) considered the SCTs to be more difficult than classical MCQs, although the mean score did not differ between the SCT and MCQ tests.ConclusionThe use of SCTs is a feasible option for the evaluation of undergraduate students. The SCT scores correlated with those obtained on classical MCQ tests.