Extra virgin olive oil improves HDL lipid fraction but not HDL-mediated cholesterol efflux capacity: a double-blind, randomised, controlled, cross-over study (OLIVAUS).

Olive oil (OO) polyphenols have been shown to improve HDL anti-atherogenic function, thus demonstrating beneficial effects against cardiovascular risk factors. The aim of the present study was to investigate the effect of extra virgin high polyphenol olive oil (HPOO) v. low polyphenol olive oil (LPOO) on the capacity of HDL to promote cholesterol efflux in healthy adults. In a double-blind, randomised cross-over trial, fifty participants (aged 38·5 (sd 13·9) years, 66 % females) were supplemented with a daily dose (60 ml) of HPOO (320 mg/kg polyphenols) or LPOO (86 mg/kg polyphenols) for 3 weeks. Following a 2-week washout period, participants crossed over to the alternate treatment. Serum HDL-cholesterol efflux capacity, circulating lipids (i.e. total cholesterol, TAG, HDL, LDL) and anthropometrics were measured at baseline and follow-up. No significant between-group differences were observed. Furthermore, no significant changes in HDL-cholesterol efflux were found within either the LPOO and HPOO treatment arms; mean changes were 0·54 % (95 % CI (0·29, 1·37)) and 0·10 % (95 % CI (0·74, 0·94)), respectively. Serum HDL increased significantly after LPOO and HPOO intake by 0·13 mmol/l (95 % CI (0·04, 0·22)) and 0·10 mmol/l (95 % CI (0·02, 0·19)), respectively. A small but significant increase in LDL of 0·14 mmol/l (95 % CI (0·001, 0·28)) was observed following the HPOO intervention. Our results suggest that additional research is warranted to further understand the effect of OO with different phenolic content on mechanisms of cholesterol efflux via different pathways in multi-ethnic populations with diverse diets.

Prediction of clinical anxious and depressive problems in mid childhood amongst temperamentally inhibited preschool children: a population study.

Shy/inhibited young children are at risk for internalising difficulties; however, for many, this temperamental style does not result in mental health problems. This study followed a population-based sample of temperamentally inhibited preschool children into mid childhood to explore the aetiology of clinical-level anxious and depressive problems. Amongst inhibited preschool children, we aimed to predict each of clinical child anxiety and depressive problems in mid childhood from a broad range of potential risks (demographics, traumatic events and broader recent stressors, parents' well-being, and parenting practices). This study is based on data from a wider population trial of Cool Little Kids that recruited a representative sample of inhibited preschool children enrolled in their year before starting school. In 2011-2012, an inhibition screen was universally distributed to parents of children in their year before school (age 4 years) across eight diverse government areas in Melbourne, Australia. Participants were 545 parents of inhibited preschoolers (78% uptake, 545/703) who were followed to mid childhood (three annual waves 2015-2017, age 7-10 years) with 84% retention (456/545). Parents completed questionnaires spanning child ages 4-10 years, along with diagnostic interviews for child anxiety. Children also completed questionnaires in mid childhood. The questionnaires encompassed a variety of potential risks including sociodemographics, traumatic events, recent life stressors, parent wellbeing and parenting practices. In mid childhood, 57% (246/430) of inhibited preschoolers had a clinical level of anxiety problems while 22% (95/432) had depressive problems (by one or more sources). The aetiology analyses highlighted parent distress and parenting practices (overinvolved/protective, harsh discipline) as key predictors of inhibited preschoolers' internalising problems by mid childhood. Some high-risk families may not have participated. Child depression was not assessed with a diagnostic interview. The measures did not include every possible risk factor. The findings lend support to parenting programs for shy/inhibited young children that aim to prevent the development of anxiety and depression as they grow.

Follow-up of the Cool Little Kids translational trial into middle childhood.

BACKGROUND: Public health advocates have highlighted internalising problems as a leading cause of global burden of disease. Internalising problems (anxiety/depression) affect up to 20% of school-age children and can impact peer relations, school engagement and later employment and mortality. This translational trial aimed to determine whether a selective/indicated parenting group programme to prevent internalising distress in shy/inhibited preschool children had sustained effects in middle childhood. Translational design aspects were a brief parent-report screening tool for child inhibition offered universally across the population via preschools in the year before school, followed by an invitation to parents of all inhibited children to attend the parenting programme at venues in their local community. METHODS: Design of the study was a randomised controlled trial. The setting was 307 preschool services across eight socioeconomically diverse government areas in Melbourne, Australia. Participants were 545 parents of inhibited four-year-old children of which 456 (84%) were retained during middle childhood (age of seven to 10 years). Early intervention was the Cool Little Kids parenting group programme, and control was 'usual care' access to available support services in the community. Primary outcomes were child anxiety and depression symptoms (parent and child report) and DSM-IV anxiety disorders (assessor masked). Secondary outcomes were parenting practices and parent mental health. RESULTS: There was no significant difference in anxiety disorders between the intervention and control group during the three annual follow-ups of the cohort in middle childhood (2015 43% vs. 41%, 2016 40% vs. 36%, 2017 27% vs. 30%, respectively; p's > .05). There were also no significant differences in child anxiety or depression symptoms (by child or parent report), parenting practices or parent mental health, between the intervention and control group during middle childhood. However, a priori interaction tests suggested that for children with anxious parents, early intervention attenuated risk for middle childhood internalising problems. CONCLUSIONS: An issue for population translation is low levels of parent engagement in preventive interventions. Initial effects of the Cool Little Kids parenting group programme in reducing shy/inhibited preschool children's internalising distress at school entry dissipated over time, perhaps due to low engagement. Future translational research on early prevention of internalising problems could benefit from screening preschool children in the population at higher risk (combining temperamental inhibition and parent distress) and incorporating motivational techniques to facilitate family engagement. Trial registration ISRCTN30996662 http://www.isrctn.com/ISRCTN30996662.

Behaviour change interventions to increase physical activity in hospitalised patients: a systematic review, meta-analysis and meta-regression.

BACKGROUND: Low physical activity levels are a major problem for people in hospital and are associated with adverse outcomes. OBJECTIVE: This systematic review, meta-analysis and meta-regression aimed to determine the effect of behaviour change interventions on physical activity levels in hospitalised patients. METHODS: Randomised controlled trials of behaviour change interventions to increase physical activity in hospitalised patients were selected from a database search, supplemented by reference list checking and citation tracking. Data were synthesised with random-effects meta-analyses and meta-regression analyses, applying Grades of Recommendation, Assessment, Development and Evaluation criteria. The primary outcome was objectively measured physical activity. Secondary measures were patient-related outcomes (e.g. mobility), service level outcomes (e.g. length of stay), adverse events and patient satisfaction. RESULTS: Twenty randomised controlled trials of behaviour change interventions involving 2,568 participants (weighted mean age 67 years) included six trials with a high risk of bias. There was moderate-certainty evidence that behaviour change interventions increased physical activity levels (SMD 0.34, 95% CI 0.14-0.55). Findings in relation to mobility and length of stay were inconclusive. Adverse events were poorly reported. Meta-regression found behaviour change techniques of goal setting (SMD 0.29, 95% CI 0.05-0.53) and feedback (excluding high risk of bias trials) (SMD 0.35, 95% CI 0.11-0.60) were independently associated with increased physical activity. CONCLUSIONS: Targeted behaviour change interventions were associated with increases in physical activity in hospitalised patients. The trials in this review were inconclusive in relation to the patient-related or health service benefits of increasing physical activity in hospital.

Cool Little Kids translational trial to prevent internalising: two-year outcomes and prediction of parent engagement.

BACKGROUND: The aim was to determine outcomes in the first year of school of a population-delivered parenting program to prevent internalising problems in temperamentally inhibited preschool children and predictors of engagement in parenting groups. METHOD: Design: Randomised controlled trial. SETTING: 307 preschool services across eight socio-economically diverse government areas in Melbourne, Australia. PARTICIPANTS: 545 parents of inhibited 4-year-old children; 469 (86%) retained at two-year follow-up. INTERVENTION: Cool Little Kids program. Primary outcomes were child internalising symptoms and anxiety disorders. Secondary outcomes were parenting, parent well-being and engagement. Trial registration ISRCTN30996662 http://www.isrctn.com/ISRCTN30996662. RESULTS: In the first year of school (M (SD) age 6.7 (0.4) years), child anxiety symptoms were reduced in the intervention versus control arm (PAS-R M (SD): total 36.2 (17.2) versus 39.4 (18.5); adjusted difference -3.26, 95% CI -6.46 to -0.05, p = .047; specific fears 9.1 (6.2) versus 10.7 (6.8), adjusted difference -1.53; 95% CI -2.69 to -0.38, p = .009). However, there was little difference in broader child internalising (CMFWQ M (SD): 2.2 (0.5) versus 2.3 (0.6); adjusted difference -0.03, 95% CI -0.13 to 0.06, p = .489) or anxiety disorders (37.6% vs. 42.6%; adjusted OR 0.79, 95% CI 0.53 to 1.18, p = .242). Lower income, younger mothers, less educated and more culturally diverse fathers engaged less with the intervention. Continued skills practice was less frequent for parents of girls and in advantaged neighbourhoods. CONCLUSIONS: There were population effects of Cool Little Kids in the first year of school for anxiety symptoms but not disorders. Considering motivation techniques to engage subgroups of families would be helpful in translation research.

Tree pollen exposure is associated with reduced lung function in children.

BACKGROUND: Allergic disease is a recognized global epidemic and a significant cause of ill health and poor quality of life. The prevalence of pollen allergy is high throughout the world, and pollen exposure itself plays a role in emergency department presentations and hospitalizations for asthma. Lung function and airway inflammation are important measures of asthma activity and control. OBJECTIVE: To examine associations between exposure to multiple pollen types and lung function and markers of airway inflammation at 8 and 14 years of age, and to explore potential modification by residential greenness. METHODS: A cohort of high-risk children living in Sydney, Australia had spirometry and fractional exhaled nitric oxide (FeNO) measured at 8 and 14 years of age. Ambient pollen concentration on the day of lung function measurement and up to three days prior was used as the exposure measure. Residential greenness was derived from satellite imagery. We modelled the association between six pollen types and lung function and FeNO. We also assessed modifying effects of residential greenness. RESULTS: Casuarina, cypress and Pinus pollen in the air the day before measurement and 3 days prior respectively, were associated with reduced lung function in 8-year-olds. The pollen exposures were associated with decreases in FEV1 and FVC; however, the FEV1 /FVC ratio was not affected. Effect modification by greenness was not observed due to loss of power. CONCLUSIONS & CLINICAL RELEVANCE: Airborne tree pollen of cypress, Casuarina and Pinus and not grass in some regions may be detrimental to childhood lung function.

Pollen exposure at birth and adolescent lung function, and modification by residential greenness.

BACKGROUND: Exposure to high levels of pollen in infancy is a risk factor for allergic respiratory diseases in later childhood, but effects on lung function are not fully understood. We aim to examine associations between grass pollen exposure in the first months of life and lung function at 12 and 18 years, and explore potential modification. METHODS: Using the Melbourne Atopy Cohort Study, a birth cohort of children with a family history of allergic diseases, we modeled the association between cumulative grass pollen exposure up to 3 months after birth, on FEV1 , FVC, and FEV1 /FVC ratio at 12 and 18 years. We also assessed modifying effects of residential greenness levels (derived from satellite imagery), asthma, and early life sensitization to ryegrass. RESULTS: Grass pollen exposure in the first 7 days was associated with a reduction in FEV1 (-15.5 mL; 95% CI: -27.6, -3.3 per doubling of pollen count) and FVC (-20.8 mL; -35.4, -6.1) at 12 years, but not at 18 years. Increase in cumulative grass pollen exposure up to 3 months was negatively associated with FVC at 12 and 18. Exposure to high residential greenness modified the association at 18 years. CONCLUSION: Early exposure to grass pollen was associated with decreased lung function in children and adolescents. Targeted interventions for pollen avoidance strategies that take into account local topography could be implemented alongside other clinical interventions such as immunotherapy.

Powerful differential expression analysis incorporating network topology for next-generation sequencing data.

MOTIVATION: RNA-seq has become the technology of choice for interrogating the transcriptome. However, most methods for RNA-seq differential expression (DE) analysis do not utilize prior knowledge of biological networks to detect DE genes. With the increased availability and quality of biological network databases, methods that can utilize this prior knowledge are needed and will offer biologists with a viable, more powerful alternative when analyzing RNA-seq data. RESULTS: We propose a three-state Markov Random Field (MRF) method that utilizes known biological pathways and interaction to improve sensitivity and specificity and therefore reducing false discovery rates (FDRs) when detecting differentially expressed genes from RNA-seq data. The method requires normalized count data (e.g. in Fragments or Reads Per Kilobase of transcript per Million mapped reads (FPKM/RPKM) format) as its input and it is implemented in an R package pathDESeq available from Github. Simulation studies demonstrate that our method outperforms the two-state MRF model for various sample sizes. Furthermore, for a comparable FDR, it has better sensitivity than DESeq, EBSeq, edgeR and NOISeq. The proposed method also picks more top Gene Ontology terms and KEGG pathways terms when applied to real dataset from colorectal cancer and hepatocellular carcinoma studies, respectively. Overall, these findings clearly highlight the power of our method relative to the existing methods that do not utilize prior knowledge of biological network. AVAILABILITY AND IMPLEMENTATION: As an R package at https://github.com/MalathiSIDona/pathDESeq. TO INSTALL THE PACKAGE TYPE: install_github("MalathiSIDona/pathDESeq",build_vignettes = TRUE). After installation, type vignette("pathDESeq") to access the vignette. CONTACT: a.salim@latrobe.edu.au. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

The role of human rhinovirus (HRV) species on asthma exacerbation severity in children and adolescents.

OBJECTIVE: It is recognized that human rhinovirus (HRV) infection is an important factor in asthma exacerbations requiring hospitalization in children. However, previous studies have disagreed on the differential impact of various HRV species. We sought to assess the impact of HRV species on the severity of asthma exacerbations in children and adolescents. We also examined whether the effect of HRV species on severity was modified by age and gender. METHODS: Virus strain was determined for 113 children with HRV detectable at the time of admission for asthma exacerbation. Patient characteristics were collected on admission and exacerbation severity was scored using several validated scales. RESULTS: HRV species by itself was not associated with moderate/severe vs. mild exacerbations. Boys with HRV-C infections were more likely (OR: 3.7, 95% CI: 1.2-13.4) to have a moderate/severe exacerbation than girls with HRV-C (p = 0.04 for interaction term). Higher odds were observed in younger boys (3 years old: OR: 9.1, 95% CI: 1.8-47.1 vs 5 years old: OR: 3.3, 95% CI: 0.9-11.8 vs 7 years old: OR: 1.2, 95% CI: 0.2-6.6). In contrast, children with HRV-C infection and sensitized to pollen during the pollen season were less likely to have moderate/severe exacerbations (p = 0.01 for the interaction term). CONCLUSION: Acute asthma exacerbations are more likely to be moderate/severe in boys under 5 years of age who had HRV-C infection on admission. The opposite was found in children with sensitization to pollen during pollen season.

Translational delivery of Cool Little Kids to prevent child internalising problems: Randomised controlled trial.

OBJECTIVE: To determine whether a population-delivered parenting programme assists in preventing internalising problems at school entry for preschool children at-risk with temperamental inhibition. METHODS: Design: a randomised controlled trial was used. SETTING: the setting was 307 preschool services across eight socioeconomically diverse government areas in Melbourne, Australia. PARTICIPANTS: a total of 545 parents of inhibited 4-year-old children: 498 retained at 1-year follow up. Early intervention: Cool Little Kids parenting group programme was implemented. Primary outcomes: the primary outcomes were child DSM-IV anxiety disorders (assessor blind) and internalising problems. SECONDARY OUTCOMES: the secondary outcomes were parenting practices and parent mental health. RESULTS: At 1-year follow up (mean (standard deviation) age = 5.8 (0.4) years), there was little difference in anxiety disorders between the intervention and control arms (44.2% vs 50.2%; adjusted odds ratio = 0.86, 95% confidence interval = [0.60, 1.25], p = 0.427). Internalising problems were reduced in the intervention arm (Strengths and Difficulties Questionnaire: abnormal - 24.2% vs 33.0%; adjusted odds ratio = 0.56, 95% confidence interval = [0.35, 0.89], p = 0.014; symptoms - mean (standard deviation) = 2.5 (2.0) vs 2.9 (2.2); adjusted mean difference = -0.47, 95% confidence interval = [-0.81, -0.13], p = 0.006). Parents' participation in the intervention was modest (29.4% attended most groups, 20.5% used skills most of the time during the year). A priori interaction tests suggested that for children with anxious parents, the intervention reduced anxiety disorders and internalising symptoms after 1 year. CONCLUSION: Offering Cool Little Kids across the population for inhibited preschoolers does not impact population outcomes after 1 year. Effects may be emerging for inhibited children at highest risk with parent anxiety. Trial outcomes will continue into mid-childhood.

Effects of testosterone treatment on body fat and lean mass in obese men on a hypocaloric diet: a randomised controlled trial.

BACKGROUND: Whether testosterone treatment has benefits on body composition over and above caloric restriction in men is unknown. We hypothesised that testosterone treatment augments diet-induced loss of fat mass and prevents loss of muscle mass. METHODS: We conducted a randomised double-blind, parallel, placebo controlled trial at a tertiary referral centre. A total of 100 obese men (body mass index ≥ 30 kg/m2) with a total testosterone level of or below 12 nmol/L and a median age of 53 years (interquartile range 47-60) receiving 10 weeks of a very low energy diet (VLED) followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of 10-weekly intramuscular testosterone undecanoate (n = 49, cases) or matching placebo (n = 51, controls). The main outcome measures were the between-group difference in fat and lean mass by dual-energy X-ray absorptiometry, and visceral fat area (computed tomography). RESULTS: A total of 82 men completed the study. At study end, compared to controls, cases had greater reductions in fat mass, with a mean adjusted between-group difference (MAD) of -2.9 kg (-5.7 to -0.2; P = 0.04), and in visceral fat (MAD -2678 mm2; -5180 to -176; P = 0.04). Although both groups lost the same lean mass following VLED (cases -3.9 kg (-5.3 to -2.6); controls -4.8 kg (-6.2 to -3.5), P = 0.36), cases regained lean mass (3.3 kg (1.9 to 4.7), P < 0.001) during weight maintenance, in contrast to controls (0.8 kg (-0.7 to 2.3), P = 0.29) so that, at study end, cases had an attenuated reduction in lean mass compared to controls (MAD 3.4 kg (1.3 to 5.5), P = 0.002). CONCLUSIONS: While dieting men receiving placebo lost both fat and lean mass, the weight loss with testosterone treatment was almost exclusively due to loss of body fat. TRIAL REGISTRATION: clinicaltrials.gov, identifier NCT01616732 , registration date: June 8, 2012.

Meta-analysis of ratios of sample variances.

When conducting a meta-analysis of standardized mean differences (SMDs), it is common to use Cohen's d, or its variants, that require equal variances in the two arms of each study. While interpretation of these SMDs is simple, this alone should not be used as a justification for assuming equal variances. Until now, researchers have either used an F-test for each individual study or perhaps even conveniently ignored such tools altogether. In this paper, we propose a meta-analysis of ratios of sample variances to assess whether the equality of variances assumptions is justified prior to a meta-analysis of SMDs. Quantile-quantile plots, an omnibus test for equal variances or an overall meta-estimate of the ratio of variances can all be used to formally justify the use of less common methods when evidence of unequal variances is found. The methods in this paper are simple to implement and the validity of the approaches are reinforced by simulation studies and an application to a real data set.

Online processing of sentences containing noun modification in young children with high-functioning autism.

BACKGROUND: There is variability in the language of children with autism, even those who are high functioning. However, little is known about how they process language structures in real time, including how they handle potential ambiguity, and whether they follow referential constraints. Previous research with older autism spectrum disorder (ASD) participants has shown that these individuals can use context to access rapidly the meaning of ambiguous words. The severity of autism has also been shown to influence the speed in which children with ASD access lexical information. AIMS: To understand more about how children with ASD process language in real time (i.e., as it unfolds). The focus was the integration of information and use of referential constraints to identify a referent named in a sentence. METHODS & PROCEDURES: We used an eye-tracking task to compare performance between young, high-functioning children with autism (HFA) and children with typical development (TD). A large sample of 5-9-year-old children (mean age = 6;8 years), 48 with HFA and 56 with TD participated; all were attending mainstream schools. For each item participants were shown a display of four images that differed in two dimensions. Each sentence contained an adjective and noun that restricted the choice from four to two (the target and competitor), followed by a prepositional phrase (e.g., the blue square with dots); this added modifying information to provide a unique description of the target. We calculated looking time at the target, the competitor and the two distractors for each 200 ms time interval as children processed the sentence and looked at the display. Generalized estimating equations were used to carry out repeated-measures analyses on the proportion of looking time to target and competitor and time to fixate to target. OUTCOMES & RESULTS: Children in both groups (HFA and TD) looked at the target and competitor more than at the distractors following the adjective and noun and following the modifying information in the prepositional phrase more at the target. However, the HFA group was significantly slower in both phases and looked proportionally less at the target. Across the sample, IQ and language did not affect the results; however, age and attention had an impact. The older children showed an advantage in processing the information as did the children with higher attention scores. CONCLUSIONS & IMPLICATIONS: The HFA group took longer than the TD group to integrate the disambiguating information provided in the course of processing a sentence and integrate it with the visual information, indicating that for the ASD group incremental processing was not as advanced as for children with ASD, and they were less sensitive to referential conventions. Training for young children with ASD on the use of referential conventions and available contextual clues may be of benefit to them in understanding the language they hear.

Long-term persistence of hormonal adaptations to weight loss.

BACKGROUND: After weight loss, changes in the circulating levels of several peripheral hormones involved in the homeostatic regulation of body weight occur. Whether these changes are transient or persist over time may be important for an understanding of the reasons behind the high rate of weight regain after diet-induced weight loss. METHODS: We enrolled 50 overweight or obese patients without diabetes in a 10-week weight-loss program for which a very-low-energy diet was prescribed. At baseline (before weight loss), at 10 weeks (after program completion), and at 62 weeks, we examined circulating levels of leptin, ghrelin, peptide YY, gastric inhibitory polypeptide, glucagon-like peptide 1, amylin, pancreatic polypeptide, cholecystokinin, and insulin and subjective ratings of appetite. RESULTS: Weight loss (mean [±SE], 13.5±0.5 kg) led to significant reductions in levels of leptin, peptide YY, cholecystokinin, insulin (P<0.001 for all comparisons), and amylin (P=0.002) and to increases in levels of ghrelin (P<0.001), gastric inhibitory polypeptide (P=0.004), and pancreatic polypeptide (P=0.008). There was also a significant increase in subjective appetite (P<0.001). One year after the initial weight loss, there were still significant differences from baseline in the mean levels of leptin (P<0.001), peptide YY (P<0.001), cholecystokinin (P=0.04), insulin (P=0.01), ghrelin (P<0.001), gastric inhibitory polypeptide (P<0.001), and pancreatic polypeptide (P=0.002), as well as hunger (P<0.001). CONCLUSIONS: One year after initial weight reduction, levels of the circulating mediators of appetite that encourage weight regain after diet-induced weight loss do not revert to the levels recorded before weight loss. Long-term strategies to counteract this change may be needed to prevent obesity relapse. (Funded by the National Health and Medical Research Council and others; ClinicalTrials.gov number, NCT00870259.).

Walking self-confidence and lower levels of anxiety are associated with meeting recommended levels of physical activity after hip fracture: a cross-sectional study.

PURPOSE: To explore whether psychological factors are associated with ability to meet recommended physical activity thresholds after hip fracture. MATERIALS AND METHODS: Cross-sectional observational study of 216 community-dwelling adults aged ≥65 years after hip fracture (mean age 79 SD 7 years, 70% female). Multiple ordinal regression analysis determined factors associated with meeting physical activity thresholds related to positive health outcomes: 4,400 and 7,100 daily steps. Explanatory variables were: walking self-confidence; falls self-efficacy; depression; anxiety; co-morbidities; previous gait aid use; nutritional status; age; and gender. RESULTS: Forty-three participants (20%) met the lower threshold of ≥4,400 to <7,100 steps and thirty participants (14%) met the upper threshold of ≥7,100 steps. Walking self-confidence was positively associated with meeting higher physical activity thresholds (adjusted odds ratio [AOR] 1.32: 95% CI 1.11 to 1.57, p = 0.002). Age (AOR 0.93: 95% CI 0.89 to 0.98, p = 0.003), DASS-21 anxiety score (AOR 0.81: 95% CI 0.69 to 0.94, p = 0.008) and comorbidity index score (AOR 0.52: 95% CI 0.36 to 0.72, p < 0.001) were negatively associated with meeting higher physical activity thresholds. CONCLUSION: Walking self-confidence and anxiety are potentially modifiable factors associated with meeting physical activity thresholds related to positive health outcomes after hip fracture.

Older people are often physically inactive after hip fracture, which can lead to negative health outcomes and increased risk of mortality.The potentially modifiable psychological factors of walking self-confidence and anxiety are associated with meeting recommended physical activity levels after hip fracture.Therapists should include assessment of psychological factors to help guide rehabilitation of patients after hip fracture.

Transforming the Model T: random effects meta-analysis with stable weights.

Standard meta-analytic theory assumes that study outcomes are normally distributed with known variances. However, methods derived from this theory are often applied to effect sizes having skewed distributions with estimated variances. Both shortcomings can be largely overcome by first applying a variance stabilizing transformation. Here we concentrate on study outcomes with Student t-distributions and show that we can better estimate parameters of fixed or random effects models with confidence intervals using stable weights or with profile approximate likelihood intervals following stabilization. We achieve even better coverage with a finite sample bias correction. Further, a simple t-interval provides very good coverage of an overall effect size without estimation of the inter-study variance. We illustrate the methodology on two meta-analytic studies from the medical literature, the effect of salt reduction on systolic blood pressure and the effect of opioids for the relief of breathlessness. Substantial simulation studies compare traditional methods with those newly proposed. We can apply the theoretical results to other study outcomes for which an effective variance stabilizer is available.

Health Professionals can Sustain Proficiency in Motivational Interviewing With a Moderate Amount of Training: An Intervention Fidelity Study.

INTRODUCTION: Motivational interviewing (MI) proficiency may erode quickly, limiting its effectiveness. We examined whether health professionals completing a 2-day workshop, with 3 to 5 hours of personalized coaching, and twice-yearly group reflections sustained proficiency for the duration of a hip fracture rehabilitation trial and whether intervention was implemented as intended. METHODS: A fidelity study was completed as part of a process evaluation of the trial that tested whether physical activity increased among hip fracture patients randomly allocated to receive MI (experimental) compared with dietary advice (control) over ten 30-minute sessions. Twelve health professionals (none were proficient in MI before trial commencement) delivered the intervention for up to 952 days. Two hundred experimental sessions (24% of all sessions, 83 patients) were randomly selected to evaluate proficiency using the MI Treatment Integrity scale; along with 20 control sessions delivered by four dietitians. Linear mixed-effects regression analyses determined whether proficiency was sustained over time. Dose was assessed from all experimental sessions (n = 840, 98 patients). RESULTS: Intervention was implemented as intended; 82% of patients received at least eight 30-minute sessions. All motivational interviewers were proficient, whereas dietitians did not inadvertently deliver MI. Time had no effect on MI proficiency (est < 0.001/d, P = .913, 95% CI, -0.001 to 0.001). DISCUSSION: MI proficiency was sustained in a large trial over 2.6 years by completing a 2-day workshop, 3 to 5 hours of personalized coaching, and twice-yearly group reflections, even for those without previous experience; further research needs to establish the maximum duration of training effectiveness.

On ratio measures of heterogeneity for meta-analyses.

As a measure of heterogeneity in meta-analysis, the coefficient of variation (CV) has been recently considered, providing researchers with a complement to the very popular I 2 measure. While I 2 measures the proportion of total variance that is due to variance of the random effects, the CV is the ratio of the standard deviation of the random effects to the effect of interest. Consequently, the CV provides a different measure of the extent of heterogeneity in a meta-analysis relative to the effect being measured. However, very large CV values can occur when the effect is small making interpretation difficult. The purpose of this article is two-fold. First, we consider variants of the CV that exist in the interval 0 , 1 which may be preferable for some researchers. Second, we provide interval estimators for the CV and its variants with excellent coverage properties. We perform simulation studies based on simulated and real data sets and draw comparisons between the methods. For both the CV and its transformations, we recommend confidence intervals using the propagating imprecision method or, as a simpler alternative but at the expense of slightly worse performance in terms of coverage, combining reduced-coverage confidence intervals for the two parameters. These interval estimators typically have better coverage properties for the CV measure than those previously considered.

Robust analogs to the coefficient of variation.

The coefficient of variation (CV) is commonly used to measure relative dispersion. However, since it is based on the sample mean and standard deviation, outliers can adversely affect it. Additionally, for skewed distributions the mean and standard deviation may be difficult to interpret and, consequently, that may also be the case for the CV . Here we investigate the extent to which quantile-based measures of relative dispersion can provide appropriate summary information as an alternative to the CV. In particular, we investigate two measures, the first being the interquartile range (in lieu of the standard deviation), divided by the median (in lieu of the mean), and the second being the median absolute deviation, divided by the median, as robust estimators of relative dispersion. In addition to comparing the influence functions of the competing estimators and their asymptotic biases and variances, we compare interval estimators using simulation studies to assess coverage.

The diamond ratio: A visual indicator of the extent of heterogeneity in meta-analysis.

The result of a meta-analysis is conventionally pictured in the forest plot as a diamond, whose length is the 95% confidence interval (CI) for the summary measure of interest. The Diamond Ratio (DR) is the ratio of the length of the diamond given by a random effects meta-analysis to that given by a fixed effect meta-analysis. The DR is a simple visual indicator of the amount of change caused by moving from a fixed-effect to a random-effects meta-analysis. Increasing values of DR greater than 1.0 indicate increasing heterogeneity relative to the effect variances. We investigate the properties of the DR, and its relationship to four conventional but more complex measures of heterogeneity. We propose for the first time a CI on the DR, and show that it performs well in terms of coverage. We provide example code to calculate the DR and its CI, and to show these in a forest plot. We conclude that the DR is a useful indicator that can assist students and researchers to understand heterogeneity, and to appreciate its extent in particular cases.