A new Lindley-Burr XII power series distribution: model, properties and applications.

A new generalized class of distributions called the Lindley-Burr XII Power Series (LBXIIPS) distribution is proposed and explored. This new class of distributions contain some special cases such as Lindley-Burr XII Poisson (LBXIIP), Lindley-Burr XII Logarithmic (LBXIIL), Lindley-Burr XII Binomial (LBXIIB) and their sub-models among others. Some structural properties of the new distribution including moments, probability weighted moments, distribution of the order statistics and entropy are derived. Maximum likelihood estimation technique is used to estimate the model parameters. A simulation study to examine the bias and mean square error of the maximum likelihood estimators is presented and finally, an application to a real data set in order to illustrate the usefulness of the new distribution is given.

Prevalence of asthma among school children in Gaborone, Botswana.

BACKGROUND: Asthma prevalence is high (>10%) in developed countries and although data is still missing for most of Africa, rates are increasing in developing regions as they become more westernized. We investigated the prevalence of asthma in school children in Gaborone, Botswana. METHODS: This was a cross sectional descriptive study. ISAAC methodology was used. A representative proportionate size random sample of two age groups of children (13-14 year olds and 6-7 year olds) was consecutively enrolled from 10 schools. The schools were selected using a table of random numbers. A minimum sample size of 924 individuals (462 from each group) was adequate to achieve a precision of 3 % around our estimated prevalence of asthma of 10% with 95% confidence assuming a non-response rate of 20%. Data was collected using the validated International study of Asthma and Allergies in children (ISAAC) questionnaire. In accordance with the ISAAC criteria, Asthma was defined as wheezing in the previous 12 months. Data was captured in microsoft excel and analysed using SPSS version 23. RESULTS: The prevalence of asthma (wheezing in the previous 12 months) was 16.5% (194/1175). Among the 6-7 year olds, the prevalence of asthma (wheezing in the previous 12 months) was 15.9%, while among the 13-14 years olds it was 16.8 %. The prevalence school type was 22.3 % in private schools versus 14.5 % in public schools. More severe asthma was associated with older children, 13-14 years. The older children reported more limited speech due to wheezing (OR= 2.0, 95% CI =1.034, 3.9, p-value=0.043), ever had asthma (OR= 1.5, 95% CI=1.031, 2.3, p-value=0.034) and wheezing during exercise (OR=3.4, 95% CI= 2.5, 4.9, p-value= <0.001) compared to the younger children 6-7 years. Children from private schools had more wheezing symptoms. They were more likely to have ever wheezed (OR=2.2, .95% CI=1.7,2.9, p-value < 0.0001), wheezed in the previous twelve months (have asthma) (OR=1.7,95%CI=1.2,2.4, p-value = 0.001), ever had asthma (OR=2.4, 95% CI=1.7,3.5, p-value< 0.0001), and wheezed during exercise (OR=1.8, 95% CI=1.4,2.4, p-value < 0.0001). CONCLUSION: The prevalence of asthma amongst school children in Gaborone, Botswana is high with older children experiencing more severe symptoms of asthma.

Bilateral Breast Reconstruction with Abdominal Free Flaps: A Single Centre, Single Surgeon Retrospective Review of 55 Consecutive Patients.

Breast reconstruction using free tissue transfer is an increasingly utilised oncoplastic procedure. The aim was to review all bilateral breast reconstructions using abdominal free flaps by a single surgeon over an 11-year period (2003-2014). A retrospective review was performed on all patients who underwent bilateral breast reconstruction using abdominal free flaps between 2003 and 2014 by the senior author (DAM). Data analysed included patient demographics, indication for reconstruction, surgical details, and complications. Fifty-five female patients (mean 48.6 years [24-71 years]) had bilateral breast reconstruction. The majority (41, 74.5%) underwent immediate reconstruction and DIEP flaps were utilised on 41 (74.5%) occasions. Major surgical complications occurred in 6 (10.9%) patients, all of which were postoperative vascular compromise of the flap. Failure to salvage the reconstruction occurred on 3 (5.5%) occasions resulting in a total flap failure rate of 2.7%. Obesity (>30 kg/m(2)) and age > 60 years were shown to have a statistically increased risk of developing postoperative complications (P < 0.05). Our experience demonstrates that abdominal free flaps for bilateral breast reconstruction fares well, with a flap failure rate of 2.7%. Increased body mass index and patient age (>60 years) were associated with higher complication rates.

Bad apples or spoiled barrels? Multilevel modelling analysis of variation in high-risk prescribing in Scotland between general practitioners and between the practices they work in.

OBJECTIVES: Primary care high-risk prescribing causes significant harm, but it is unclear if it is largely driven by individuals (a 'bad apple' problem) or by practices having higher or lower risk prescribing cultures (a 'spoiled barrel' problem). The study aimed to examine the extent of variation in high-risk prescribing between individual prescribers and between the practices they work in. DESIGN, SETTING AND PARTICIPANTS: Multilevel logistic regression modelling of routine cross-sectional data from 38 Scottish general practices for 181,010 encounters between 398 general practitioners (GPs) and 26,539 patients particularly vulnerable to adverse drug events (ADEs) of non-steroidal anti-inflammatory drugs (NSAIDs) due to age, comorbidity or co-prescribing. OUTCOME MEASURE: Initiation of a new NSAID prescription in an encounter between GPs and eligible patients. RESULTS: A new high-risk NSAID was initiated in 1953 encounters (1.1% of encounters, 7.4% of patients). Older patients, those with more vulnerabilities to NSAID ADEs and those with polypharmacy were less likely to have a high-risk NSAID initiated, consistent with GPs generally recognising the risk of NSAIDs in eligible patients. Male GPs were more likely to initiate a high-risk NSAID than female GPs (OR 1.73, 95% CI 1.39 to 2.16). After accounting for patient characteristics, 4.2% (95% CI 2.1 to 8.3) of the variation in high-risk NSAID prescribing was attributable to variation between practices, and 14.2% (95% CI 11.4 to 17.3) to variation between GPs. Three practices had statistically higher than average high-risk prescribing, but only 15.7% of GPs with higher than average high-risk prescribing and 18.5% of patients receiving such a prescription were in these practices. CONCLUSIONS: There was much more variation in high-risk prescribing between GPs than between practices, and only targeting practices with higher than average rates will miss most high-risk NSAID prescribing. Primary care prescribing safety improvement should ideally target all practices, but encourage practices to consider and act on variation between prescribers in the practice.

Alcohol consumption and interpersonal injury in a pediatric oral and maxillofacial trauma population: a retrospective review of 1,192 trauma patients.

The social, financial, and health implications of adult alcohol-related oral and maxillofacial trauma have been recognized for several years. Affordability and widespread accessibility of alcohol and issues of misuse in the pediatric trauma population have fostered concerns alcohol may be similarly implicated in young patients with orofacial trauma. The aim of this study was to review data of pediatric facial injuries at a regional maxillofacial unit, assess the prevalence of alcohol use, and review data of patients sustaining injury secondary to interpersonal violence. This study is a retrospective, 3-year review of a Regional Maxillofacial Unit (RMU) trauma database. Inclusion criterion was consecutive facial trauma patients under 16 years of age, referred to RMU for further assessment and/or management. Alcohol use and injuries sustained were reviewed. Of 1,192 pediatric facial trauma patients, 35 (2.9%) were associated with alcohol intake. A total of 145 (12.2%) alleged assault as the mechanism of injury, with older (12-15 years) (n = 129; 88.9%), male (n = 124; 85.5%) (p < 0.001) patients commonly involved and alcohol use implicated in 26 (17.9%) presentations. A proportion of vulnerable adolescents misuse alcohol to the risk of traumatic facial injury, and prospective research to accurately determine any role of alcohol in the pediatric trauma population is essential.

The rising tide of polypharmacy and drug-drug interactions: population database analysis 1995-2010.

BACKGROUND: The escalating use of prescribed drugs has increasingly raised concerns about polypharmacy. This study aims to examine changes in rates of polypharmacy and potentially serious drug-drug interactions in a stable geographical population between 1995 and 2010. METHODS: This is a repeated cross-sectional analysis of community-dispensed prescribing data for all 310,000 adults resident in the Tayside region of Scotland in 1995 and 2010. The number of drug classes dispensed and the number of potentially serious drug-drug interactions (DDIs) in the previous 84 days were calculated, and age-sex standardised rates in 1995 and 2010 compared. Patient characteristics associated with receipt of ≥ 10 drugs and with the presence of one or more DDIs were examined using multilevel logistic regression to account for clustering of patients within primary care practices. RESULTS: Between 1995 and 2010, the proportion of adults dispensed ≥ 5 drugs doubled to 20.8%, and the proportion dispensed ≥ 10 tripled to 5.8%. Receipt of ≥ 10 drugs was strongly associated with increasing age (20-29 years, 0.3%; ≥ 80 years, 24.0%; adjusted OR, 118.3; 95% CI, 99.5-140.7) but was also independently more common in people living in more deprived areas (adjusted OR most vs. least deprived quintile, 2.36; 95% CI, 2.22-2.51), and in people resident in a care home (adjusted OR, 2.88; 95% CI, 2.65-3.13). The proportion with potentially serious drug-drug interactions more than doubled to 13% of adults in 2010, and the number of drugs dispensed was the characteristic most strongly associated with this (10.9% if dispensed 2-4 drugs vs. 80.8% if dispensed ≥ 15 drugs; adjusted OR, 26.8; 95% CI 24.5-29.3). CONCLUSIONS: Drug regimens are increasingly complex and potentially harmful, and people with polypharmacy need regular review and prescribing optimisation. Research is needed to better understand the impact of multiple interacting drugs as used in real-world practice and to evaluate the effect of medicine optimisation interventions on quality of life and mortality.

Lung sounds: how doctors draw crackles and wheeze.

BACKGROUND: The content of medical records is a potential source of miscommunication between clinicians. Doctors' written entries have been criticised for their illegibility and ambiguity, but no studies have examined doctors' drawings that are commonly used for recording auscultation findings. OBJECTIVE: To compare doctors' drawings of auscultation findings, based on identical clinical information. METHODS: Doctors at the Royal London Hospital and a group of London based general practitioners (GPs) documented a respiratory examination with a drawing of the auscultation findings of bilateral mid and lower zone wheeze and right lower zone crackles. The graphical properties of each drawing were examined and the use of written captions and labels recorded. Drawings were classified into styles according to the use of symbols (defined as discrete characters or icons) and shading (cross-hatching, speckling or darkening) to depict the auscultation findings. The study was conducted between September and November 2011. RESULTS: Sixty-nine hospital doctors and 13 GPs participated. Ten drawing styles were identified from 78 completed drawings. Ten distinct symbols and a range of shading techniques were used. The most frequent style (21% of drawings) combined 'X' symbols representing crackles with musical notes for wheeze. There was inconsistency of representation across the drawings. Forty-seven (60%) drawings used an 'X' symbol exclusively to represent crackles, but six (8%) used 'X' only to represent wheeze, and 10 (13%) used 'X' to represent both findings. 91% of participants included captions or labels with their drawing. CONCLUSIONS: There was wide variation in doctors' drawings of identical auscultation findings, and inconsistency in the meaning of symbols both between and within drawings. Doctors risk incorrectly interpreting each other's drawings when they are not effectively labelled. We recommend doctors consider using a written description instead, or draw different findings with distinct symbols or shading, labelling all findings clearly.

Making electronic prescribing alerts more effective: scenario-based experimental study in junior doctors.

OBJECTIVE: Expert authorities recommend clinical decision support systems to reduce prescribing error rates, yet large numbers of insignificant on-screen alerts presented in modal dialog boxes persistently interrupt clinicians, limiting the effectiveness of these systems. This study compared the impact of modal and non-modal electronic (e-) prescribing alerts on prescribing error rates, to help inform the design of clinical decision support systems. DESIGN: A randomized study of 24 junior doctors each performing 30 simulated prescribing tasks in random order with a prototype e-prescribing system. Using a within-participant design, doctors were randomized to be shown one of three types of e-prescribing alert (modal, non-modal, no alert) during each prescribing task. MEASUREMENTS: The main outcome measure was prescribing error rate. Structured interviews were performed to elicit participants' preferences for the prescribing alerts and their views on clinical decision support systems. RESULTS: Participants exposed to modal alerts were 11.6 times less likely to make a prescribing error than those not shown an alert (OR 11.56, 95% CI 6.00 to 22.26). Those shown a non-modal alert were 3.2 times less likely to make a prescribing error (OR 3.18, 95% CI 1.91 to 5.30) than those not shown an alert. The error rate with non-modal alerts was 3.6 times higher than with modal alerts (95% CI 1.88 to 7.04). CONCLUSIONS: Both kinds of e-prescribing alerts significantly reduced prescribing error rates, but modal alerts were over three times more effective than non-modal alerts. This study provides new evidence about the relative effects of modal and non-modal alerts on prescribing outcomes.

Predictive validity of the personal qualities assessment for selection of medical students in Scotland.

BACKGROUND: The Personal Qualities Assessment (PQA) was developed to enhance medical student selection by measuring a range of non-cognitive attributes in the applicants to medical school. Applicants to the five Scottish medical schools were invited to pilot the test in 2001 and 2002. AIMS: To evaluate the predictive validity of PQA for selecting medical students. METHODS: A longitudinal cohort study was conducted in which PQA scores were compared with senior year medical school performance. RESULTS: Consent to access performance markers was obtained from 626 students (61.6% of 1017 entrants in 2002-2003). Linkable Foundation Year (4th) rankings were available for 411 (66%) students and objective structured clinical examination (OSCE) rankings for 335 (54%) of those consenting. Both samples were representative of the original cohort. No significant correlations were detected between separate elements of the PQA assessment and student performance. However, using the algorithm advocated by Powis et al. those defined as 'non-extreme' (<±1.5 SD from the cohort mean scores; SD, standard deviation) character types on the involved-detached and on the libertarian-communitarian moral orientation scales were ranked higher in OSCEs (average of 7.5% or 25 out of 335, p = 0.049). CONCLUSIONS: This study was limited by high attrition and basic outcome markers which are insensitive to relevant non-cognitive characteristics. However, it is the largest currently available study of predictive validity for the PQA assessment. There was one finding of significance: that those students who were identified by PQA as 'not extreme' on the two personal characteristics scales performed better in an OSCE measure of professionalism. Futures studies are required since psychometric testing for both cognitive and non-cognitive attributes are increasingly used in admission process and these should include more and better measures of professionalism against which to correlate non-cognitive traits.

Planning and analysis of cross-over trials in infertility.

The use of cross-over trials in investigating treatments for infertility is discussed. A simple possible approach to analyzing such trials using the Mantel-Haenszel procedure is explained. A more flexible approach based on the normal-binomial mixture model of Ezzet and Whitehead is examined. It is shown how this may be implemented in various statistical packages by applying it to two real examples of trials in infertility. An approach that may be used to compare designs via simulation is explained briefly. It is concluded that provided that cross-over trials in infertility are regarded as parallel group trials with extra information rather than as cross-over trials with missing information, their use may be more promising than that has previously been concluded.