Effectiveness of strategies to increase participation in school-based epidemiological surveys: a rapid review.

OBJECTIVE: Rapid review of the literature on strategies to increase participation rates in school-based epidemiological surveys. BASIC RESEARCH DESIGN: Rapid review. MEDLINE and Embase databases were searched for articles written in English from 2000 onwards. Synthesised evidence and primary research were included as data sources from peer reviewed journals and reports. INTERVENTIONS: Any strategy aiming to increase participation in school-based health surveys. The comparator was usual procedure or an alternative strategy to increase participation. MAIN OUTCOME MEASURES: Primary outcomes included participation and consent rates. Secondary outcomes were feasibility, acceptability and adverse effects. RESULTS: The search identified 591 unique records, of which 587 were excluded. Four studies were suitable for inclusion, including one systematic review, one randomised controlled trial, one cross-sectional study and one retrospective analysis. Based on very low certainty evidence, recommendations for maximising participation rates in one systematic review of US studies included: promoting the survey to school staff, parents and students; disseminating study information using direct rather than mediated methods; offering incentives to schools, staff and participants; following up non-responders; and employing a research team member to co-ordinate and monitor recruitment. However, UK studies found that different strategies did not increase participation more than that achieved by a standard approach (delivery of covering letter/consent forms via the child with no follow-up of non-responders). CONCLUSION: Given the lack of evidence of effectiveness of alternative strategies in the UK, additional measures beyond existing standard approaches for active consent cannot be recommended.

Augmenting lung cancer diagnosis on chest radiographs: positioning artificial intelligence to improve radiologist performance.

AIM: To evaluate the role that artificial intelligence (AI) could play in assisting radiologists as the first reader of chest radiographs (CXRs), to increase the accuracy and efficiency of lung cancer diagnosis by flagging positive cases before passing the remaining examinations to standard reporting. MATERIALS AND METHODS: A dataset of 400 CXRs including 200 difficult lung cancer cases was curated. Examinations were reviewed by three FRCR radiologists and an AI algorithm to establish performance in tumour identification. AI and radiologist labels were combined retrospectively to simulate the proposed AI triage workflow. RESULTS: When used as a standalone algorithm, AI classification was equivalent to the average radiologist performance. The best overall performances were achieved when AI was combined with radiologists, with an average reduction of missed cancers of 60%. Combination with AI also standardised the performance of radiologists. The greatest improvements were observed when common sources of errors were present, such as distracting findings. DISCUSSION: The proposed AI implementation pathway stands to reduce radiologist errors and improve clinician reporting performance. Furthermore, taking a radiologist-centric approach in the development of clinical AI holds promise for catching systematically missed lung cancers. This represents a tremendous opportunity to improve patient outcomes for lung cancer diagnosis.

Diagnosis of normal chest radiographs using an autonomous deep-learning algorithm.

AIM: To evaluate the suitability of a deep-learning (DL) algorithm for identifying normality as a rule-out test for fully automated diagnosis in frontal adult chest radiographs (CXR) in an active clinical pathway. MATERIALS AND METHODS: This multicentre study included 3,887 CXRs from four distinct NHS institutions. A convolutional neural network (CNN) was developed and trained prior to this study and was used to classify a subset of examinations with the lowest abnormality scores as high confidence normal (HCN). For each radiograph, the ground truth (GT) was established using two independent reviewers and an arbitrator in case of discrepancy. RESULTS: The DL algorithm was able to classify 15% of all examinations as HCN, with a corresponding precision of 97.7%. There were 0.33% of examinations classified incorrectly as HCN, with 84.6% of these examinations identified as borderline cases by the radiologist GT process. CONCLUSION: A DL algorithm can achieve a high level of precision as a fully automated diagnostic tool for reporting a subset of CXRs as normal. The removal of 15% of all CXRs has the potential to significantly reduce workload and focus radiology resources on more complex examinations. To optimise performance, site-specific deployment of algorithms should occur with robust feedback mechanisms for incorrect classifications.

Risky Sexual Behaviors, Substance Use, and Perceptions of Risky Behaviors Among Criminal Justice Involved Women Who Trade Sex.

This study examined risky sexual behaviors, Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV)-defined alcohol and substance use disorders, and perceptions of risky behaviors among community released, justice-involved women, who are currently trading sex (CTS), formerly traded sex (FTS), or have never traded sex. Data were derived from 266 sexually active women recruited from a Municipal Drug Court System in St. Louis, Missouri. In an adjusted multinomial regression model, being dependent on alcohol and cocaine was the most robust correlate of sex-trading status (adjusted odds ratio [AOR]: CTS = 4.21, FTS = 4.66). Perceptions of sexual risk and HIV were significantly associated with CTS (AOR = 3.39), however, not FTS. Other significant correlates of sex trading status included age, lifetime injection drug use, lower education, child sexual abuse, and unstable housing. Gender-specific interventions tailored toward currently and formerly sex-trading women are needed.

Obesity and obesogenic growth are both highly heritable and modified by diet in a nonhuman primate model, the African green monkey (Chlorocebus aethiops sabaeus).

OBJECTIVE: In humans, the ontogeny of obesity throughout the life course and the genetics underlying it has been historically difficult to study. We compared, in a non-human primate model, the lifelong growth trajectories of obese and non-obese adults to assess the heritability of and map potential genomic regions implicated in growth and obesity. STUDY POPULATION: A total of 905 African green monkeys, or vervets (Chlorocebus aethiops sabaeus) (472 females, 433 males) from a pedigreed captive colony. METHODS: We measured fasted body weight (BW), crown-to-rump length (CRL), body-mass index (BMI) and waist circumference (WC) from 2000 to 2015. We used a longitudinal clustering algorithm to detect obesogenic growth, and logistic growth curves implemented in nonlinear mixed effects models to estimate three growth parameters. We used maximum likelihood variance decomposition methods to estimate the genetic contributions to obesity-related traits and growth parameters, including a test for the effects of a calorie-restricted dietary intervention. We used multipoint linkage analysis to map implicated genomic regions. RESULTS: All measurements were significantly influenced by sex, and with the exception of WC, also influenced by maternal and post-natal diet. Chronic obesity outcomes were significantly associated with a pattern of extended growth duration with slow growth rates for BW. After accounting for environmental influences, all measurements were found to have a significant genetic component to variability. Linkage analysis revealed several regions suggested to be linked to obesity-related traits that are also implicated in human obesity and metabolic disorders. CONCLUSIONS: As in humans, growth patterns in vervets have a significant impact on adult obesity and are largely under genetic control with some evidence for maternal and dietary programming. These results largely mirror findings from human research, but reflect shorter developmental periods, suggesting that the vervet offers a strong genetic model for elucidating the ontogeny of human obesity.

Combined genome-wide linkage and targeted association analysis of head circumference in autism spectrum disorder families.

BACKGROUND: It has long been recognized that there is an association between enlarged head circumference (HC) and autism spectrum disorder (ASD), but the genetics of HC in ASD is not well understood. In order to investigate the genetic underpinning of HC in ASD, we undertook a genome-wide linkage study of HC followed by linkage signal targeted association among a sample of 67 extended pedigrees with ASD. METHODS: HC measurements on members of 67 multiplex ASD extended pedigrees were used as a quantitative trait in a genome-wide linkage analysis. The Illumina 6K SNP linkage panel was used, and analyses were carried out using the SOLAR implemented variance components model. Loci identified in this way formed the target for subsequent association analysis using the Illumina OmniExpress chip and imputed genotypes. A modification of the qTDT was used as implemented in SOLAR. RESULTS: We identified a linkage signal spanning 6p21.31 to 6p22.2 (maximum LOD = 3.4). Although targeted association did not find evidence of association with any SNP overall, in one family with the strongest evidence of linkage, there was evidence for association (rs17586672, p = 1.72E-07). CONCLUSIONS: Although this region does not overlap with ASD linkage signals in these same samples, it has been associated with other psychiatric risk, including ADHD, developmental dyslexia, schizophrenia, specific language impairment, and juvenile bipolar disorder. The genome-wide significant linkage signal represents the first reported observation of a potential quantitative trait locus for HC in ASD and may be relevant in the context of complex multivariate risk likely leading to ASD.

Annealing Stability Study of Co20Fe60B20\MgO\ Co20Fe60B20 Perpendicular Magnetic Tunnel Junctions.

A full Co20Fe60B20\MgO\ Co20Fe60B20 perpendicular magnetic tunnel junction (pMTJ) with (Co\Pt) multilayers as pinning layers and different functional multilayers stacks were made and annealed at different temperatures. The tunneling magnetoresistance ratio (TMR) and MgO barrier resistance-area product (RA) were measured and analyzed as a function of annealing temperature. The TMR of pMTJs dramatically declines with increasing annealing temperatures from 320 °C to 400 °C while the RA increases with temperature from 375 °C to 450 °C. The pMTJs and partial stacks were also measured in a vibrating sample magnetometer (VSM). We found that the (Co\Pt) multilayers are very stable and maintain a magnetization direction perpendicular to the film plane up to 450 °C. However, the magnetization direction of the CoFeB above and below the MgO barrier rotates from perpendicular to in-plane with increasing annealing temperature. Furthermore, the CoFeB layer influences the adjacent (Co\Pt) layers to rotate at the same time. The pMTJs' elemental depth profiles in the as deposited and annealed states were determined by Secondary Ion Mass Spectrometry (SIMS). We found that Boron and Tantalum migrate towards the top of the stack. The other elements (Platinum, Cobalt, Ruthenium, and Magnesium) are very stable and do not interdiffuse during annealing up to 450°C.

Genome-wide significant loci for addiction and anxiety.

BACKGROUND: Psychiatric comorbidity is common among individuals with addictive disorders, with patients frequently suffering from anxiety disorders. While the genetic architecture of comorbid addictive and anxiety disorders remains unclear, elucidating the genes involved could provide important insights into the underlying etiology. METHODS: Here we examine a sample of 1284 Mexican-Americans from randomly selected extended pedigrees. Variance decomposition methods were used to examine the role of genetics in addiction phenotypes (lifetime history of alcohol dependence, drug dependence or chronic smoking) and various forms of clinically relevant anxiety. Genome-wide univariate and bivariate linkage scans were conducted to localize the chromosomal regions influencing these traits. RESULTS: Addiction phenotypes and anxiety were shown to be heritable and univariate genome-wide linkage scans revealed significant quantitative trait loci for drug dependence (14q13.2-q21.2, LOD=3.322) and a broad anxiety phenotype (12q24.32-q24.33, LOD=2.918). Significant positive genetic correlations were observed between anxiety and each of the addiction subtypes (ρg=0.550-0.655) and further investigation with bivariate linkage analyses identified significant pleiotropic signals for alcohol dependence-anxiety (9q33.1-q33.2, LOD=3.054) and drug dependence-anxiety (18p11.23-p11.22, LOD=3.425). CONCLUSIONS: This study confirms the shared genetic underpinnings of addiction and anxiety and identifies genomic loci involved in the etiology of these comorbid disorders. The linkage signal for anxiety on 12q24 spans the location of TMEM132D, an emerging gene of interest from previous GWAS of anxiety traits, whilst the bivariate linkage signal identified for anxiety-alcohol on 9q33 peak coincides with a region where rare CNVs have been associated with psychiatric disorders. Other signals identified implicate novel regions of the genome in addiction genetics.

The acceptability of healthcare: from satisfaction to trust.

The assessment of healthcare quality increasingly emphasises lay acceptability, as evidenced by the emergence of patient satisfaction and patient-centred care in the literature and in policy. In this paper we aim to provide a conceptual overview of acceptability and propose ways to enhance its assessment. Firstly, we map how acceptability's importance in quality assessments has increased and how the term acceptability has been used as synonymous with patient satisfaction, despite it being a broader concept. We then critique the concept of patient satisfaction and its measurement and challenge its use as an indicator of acceptability and quality. By drawing on our research and those of others, the second half of the paper describes how trust in clinicians and health services has emerged as a related concept, including a theoretical discussion of trust in healthcare outlining how it can be built, undermined and abused. We propose trust as an alternative indicator of acceptability in healthcare quality and review its measurement. Finally, we consider how healthcare policy may impact on trust and make recommendations for future research.

Species turnover (ß-diversity) in ectomycorrhizal fungi linked to NH4+ uptake capacity.

Ectomycorrhizal (EcM) fungal communities may be shaped by both deterministic and stochastic processes, potentially influencing ecosystem development and function. We evaluated community assembly processes for EcM fungi of Pseudotsuga menziesii among 12 sites up to 400 km apart in southwest British Columbia (Canada) by investigating species turnover (ß-diversity) in relation to soil nitrogen (N) availability and physical distance. We then examined functional traits for an N-related niche by quantifying net fluxes of NH4+, NO3- and protons on excised root tips from three contrasting sites using a microelectrode ion flux measurement system. EcM fungal communities were well aligned with soil N availability and pH, with no effect of site proximity (distance-decay curve) on species assemblages. Species turnover was significant (ß(1/2) = 1.48) along soil N gradients, with many more Tomentella species on high N than low N soils, in contrast to Cortinarius species. Ammonium uptake was greatest in the spring on the medium and rich sites and averaged over 190 nmol/m(2)/s for Tomentella species. The lowest uptake rates of NH4+ were by nonmycorrhizal roots of axenically grown seedlings (10 nmol/m(2)/s), followed by Cortinarius species (60 nmol/m(2)/s). EcM roots from all sites displayed only marginal uptake of nitrate (8.3 nmol/m(2)/s). These results suggest NH4+ uptake capacity is an important functional trait influencing the assembly of EcM fungal communities. The diversity of EcM fungal species across the region arguably provides critical belowground adaptations to organic and inorganic N supply that are integral to temperate rainforest ecology.

Waist circumference is genetically correlated with incident Type 2 diabetes in Mexican-American families.

AIMS: We aimed to determine the genetic and environmental correlation between various anthropometric indexes and incident Type 2 diabetes with a focus on waist circumference. METHODS: We used the data on extended Mexican-American families (808 subjects, 7617.92 person-years follow-up) from the San Antonio Family Heart Study and estimated the genetic and environmental correlations of 16 anthropometric indexes with the genetic liability of incident Type 2 diabetes. We performed bivariate trait analyses using the solar software package. RESULTS: All 16 anthropometric indexes were significantly heritable (range of heritabilities 0.24-0.99). Thirteen indexes were found to have significant environmental correlation with the liability of incident Type 2 diabetes. In contrast, only anthropometric indexes consisting of waist circumference (waist circumference, waist-hip ratio and waist-height ratio) were significantly genetically correlated (genetic correlation coefficients: 0.45, 0.55 and 0.44, respectively) with the liability of incident Type 2 diabetes. We did not observe such a correlation for BMI. CONCLUSIONS: Waist circumference as a predictor of future Type 2 diabetes is supported by the finding that they share common genetic influences.

Localization of a major susceptibility locus influencing preterm birth.

Preterm birth (PTB) is a complex trait, but little is known regarding its major genetic determinants. The objective of this study is to localize genes that influence susceptibility to PTB in Mexican Americans (MAs), a minority population in the USA, using predominantly microfilmed birth certificate-based data obtained from the San Antonio Family Birth Weight Study. Only 1302 singleton births from 288 families with information on PTB and significant covariates were considered for genetic analysis. PTB is defined as a childbirth that occurs at <37 completed weeks of gestation, and the prevalence of PTB in this sample was 6.4%. An ∼10 cM genetic map was used to conduct a genome-wide linkage analysis using the program SOLAR. The heritability of PTB was high (h(2) ± SE: 0.75 ± 0.20) and significant (P = 4.5 × 10(-5)), after adjusting for the significant effects of birthweight and birth order. We found significant evidence for linkage of PTB (LOD = 3.6; nominal P = 2.3 × 10(-5); empirical P = 1.0 × 10(-5)) on chromosome 18q between markers D18S1364 and D18S541. Several other chromosomal regions (2q, 9p, 16q and 20q) were also potentially linked with PTB. A strong positional candidate gene in the 18q linked region is SERPINB2 or PAI-2, a member of the plasminogen activator system that is associated with various reproductive processes. In conclusion, to our knowledge, perhaps for the first time in MAs or US populations, we have localized a major susceptibility locus for PTB on chromosome 18q21.33-q23.

Transcriptomics of cortical gray matter thickness decline during normal aging.

INTRODUCTION: We performed a whole-transcriptome correlation analysis, followed by the pathway enrichment and testing of innate immune response pathway analyses to evaluate the hypothesis that transcriptional activity can predict cortical gray matter thickness (GMT) variability during normal cerebral aging. METHODS: Transcriptome and GMT data were available for 379 individuals (age range=28-85) community-dwelling members of large extended Mexican American families. Collection of transcriptome data preceded that of neuroimaging data by 17 years. Genome-wide gene transcriptome data consisted of 20,413 heritable lymphocytes-based transcripts. GMT measurements were performed from high-resolution (isotropic 800 µm) T1-weighted MRI. Transcriptome-wide and pathway enrichment analysis was used to classify genes correlated with GMT. Transcripts for sixty genes from seven innate immune pathways were tested as specific predictors of GMT variability. RESULTS: Transcripts for eight genes (IGFBP3, LRRN3, CRIP2, SCD, IDS, TCF4, GATA3, and HN1) passed the transcriptome-wide significance threshold. Four orthogonal factors extracted from this set predicted 31.9% of the variability in the whole-brain and between 23.4 and 35% of regional GMT measurements. Pathway enrichment analysis identified six functional categories including cellular proliferation, aggregation, differentiation, viral infection, and metabolism. The integrin signaling pathway was significantly (p<10(-6)) enriched with GMT. Finally, three innate immune pathways (complement signaling, toll-receptors and scavenger and immunoglobulins) were significantly associated with GMT. CONCLUSION: Expression activity for the genes that regulate cellular proliferation, adhesion, differentiation and inflammation can explain a significant proportion of individual variability in cortical GMT. Our findings suggest that normal cerebral aging is the product of a progressive decline in regenerative capacity and increased neuroinflammation.

The self-reported oral health status and dental attendance of smokers and non-smokers.

AIM: To report the oral health status and dental attendance of smokers and non-smokers. METHODS: A postal survey enquiring about smoking status, stop smoking advice, dental attendance and perceptions of oral health was conducted in Yorkshire and the Humber, U.K., in 2008. To address potential biases data were weighted to account for variations in gender, age and deprivation. Data were analysed using descriptive statistics, chi-square tests and binary logistic regression. RESULTS: A response rate of 43.1% was achieved (n=10,864). Across all deprivation quintiles, smokers (17.5% of respondents) were more likely than non-smokers to report fair, poor or very poor oral health (p<0.001). Smokers in the least deprived areas were more likely than non-smokers to attend the dentist symptomatically (p<0.001). Advice to quit was most frequently gained from GP services followed by NHS Stop Smoking Services and dental teams. CONCLUSIONS: Smokers were more likely than non-smokers to have a poor self-rated oral health status and attend the dentist symptomatically, irrespective of deprivation.

What matters to patients when their care is delegated to dental therapists?

AIM: To explore the experiences of adult patients and parents of child patients when their oral healthcare is delegated to dental therapists. METHOD: Narrative study using semi-structured in-depth interviews of a purposive sample of patients (n = 15) and parents of child patients (n = 3) who have been treated by therapists. RESULTS: Overall, participants reported positive experiences of treatment provided by therapists. Two main themes emerged from the data. The first; perceptions of the nature of dental services appeared related to the second; trust and familiarity in the dental team. Perceptions of the nature of dental services ranged from viewing dentistry as a public service to that of a private service, consistent with a more consumerist stance. Within this theme, three dimensions were identified: rationale for skill-mix; team hierarchy and importance of choice and cost. Consumerist perspectives saw cost reduction, rather than increasing access, as the rationale for skill-mix. Such perspectives tended to focus on hierarchy and a rights-based approach, envisaging dentists as the head of the team and emphasising their right to choose a clinician. Trust in and familiarity with the dental team appeared critical for therapists to be acceptable. Two dimensions were important in developing trust: affective behaviour and communication and continuity of care. Two further dimensions were identified in this theme: experience over qualification and awareness of therapists. Where trust and familiarity existed, participants emphasised the importance of their experiences of care over the qualifications of the providing clinician. Equally, trust in the dentist delegating care appeared to reassure participants, despite awareness of the role of therapists and their training being universally low. CONCLUSION: Regardless of perspective, views and experiences of treatment provided by therapists were positive. However, trust in and familiarity with the dental team appeared critical. Trust was apparently founded on dental teams' affective behaviour, communication skills and continuity of care. There are implications for skill-mix where staff turnover is high, as this is likely to compromise familiarity, continuity of care and ultimately trust.

QTL-based association analyses reveal novel genes influencing pleiotropy of metabolic syndrome (MetS).

OBJECTIVE: Metabolic Syndrome (MetS) is a phenotype cluster predisposing to type 2 diabetes and cardiovascular disease. We conducted a study to elucidate the genetic basis underlying linkage signals for multiple representative traits of MetS that we had previously identified at two significant QTLs on chromosomes 3q27 and 17p12. DESIGN AND METHODS: We performed QTL-specific genomic and transcriptomic analyses in 1,137 individuals from 85 extended families that contributed to the original linkage. We tested in SOLAR association of MetS phenotypes with QTL-specific haplotype-tagging SNPs as well as transcriptional profiles of peripheral blood mononuclear cells (PBMCs). RESULTS: SNPs significantly associated with MetS phenotypes under the prior hypothesis of linkage mapped to seven genes at 3q27 and seven at 17p12. Prioritization based on biologic relevance, SNP association, and expression analyses identified two genes: insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) at 3q27 and tumor necrosis factor receptor 13B (TNFRSF13B) at 17p12. Prioritized genes could influence cell-cell adhesion and adipocyte differentiation, insulin/glucose responsiveness, cytokine effectiveness, plasma lipid levels, and lipoprotein densities. CONCLUSIONS: Using an approach combining genomic, transcriptomic, and bioinformatic data we identified novel candidate genes for MetS.

P-selectin Expression Tracks Cerebral Atrophy in Mexican-Americans.

BACKGROUND AND PURPOSE: We hypothesized that the P-selectin (SELP) gene, localized to a region on chromosome 1q24, pleiotropically contributes to increased blood pressure and cerebral atrophy. We tested this hypothesis by performing genetic correlation analyses for 13 mRNA gene expression measures from P-selectin and 11 other genes located in 1q24 region and three magnetic resonance imaging derived indices of cerebral integrity. METHODS: The subject pool consisted of 369 (219F; aged 28-85, average = 47.1 ± 12.7 years) normally aging, community-dwelling members of large extended Mexican-American families. Genetic correlation analysis decomposed phenotypic correlation coefficients into genetic and environmental components among 13 leukocyte-based mRNA gene expressions and three whole-brain and regional measurements of cerebral integrity: cortical gray matter thickness, fractional anisotropy of cerebral white matter, and the volume of hyperintensive WM lesions. RESULTS: From the 13 gene expressions, significant phenotypic correlations were only found for the P- and L-selectin expression levels. Increases in P-selectin expression levels tracked with decline in cerebral integrity while the opposite trend was observed for L-selectin expression. The correlations for the P-selectin expression were driven by shared genetic factors, while the correlations with L-selectin expression were due to shared environmental effects. CONCLUSION: This study demonstrated that P-selectin expression shared a significant variance with measurements of cerebral integrity and posits elevated P-selectin expression levels as a potential risk factor of hypertension-related cerebral atrophy.

What do we really know about UK paediatric dental general anaesthesia services?

Dental general anaesthesia (DGA) is only permitted within a hospital setting where critical care facilities are available. Recently, concern has been expressed about the number of hospital admissions for the dental care of children following the publication of a high profile paper which highlighted an apparent increase in children being admitted for extractions due to caries under DGA. Coincidentally new best practice standards for paediatric DGA services have been published. An evaluation of DGA services in Yorkshire and the Humber suggested that existing monitoring was inadequate and is unlikely to represent true levels of activity and that any apparent increase may reflect the method of remuneration for services. In fact, recent changes in service structure and changes to improve quality have reduced DGA activity in some areas. In addition, the evaluation revealed that many services were not meeting standards of best practice.

Genome-wide linkage scan for quantitative trait loci underlying normal variation in heel bone ultrasound measures.

Quantitative ultrasound (QUS) traits are correlated with bone mineral density (BMD), but predict risk for future fracture independent of BMD. Only a few studies, however, have sought to identify specific genes influencing calcaneal QUS measures. The aim of this study was to conduct a genome-wide linkage scan to identify quantitative trait loci (QTL) influencing normal variation in QUS traits. QUS measures were collected from a total of 719 individuals (336 males and 383 females) from the Fels Longitudinal Study who have been genotyped and have at least one set of QUS measurements. Participants ranged in age from 18.0 to 96.6 years and were distributed across 110 nuclear and extended families. Using the Sahara ® bone sonometer, broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness index (QUI) were collected from the right heel. Variance components based linkage analysis was performed on the three traits using 400 polymorphic short tandem repeat (STR) markers spaced approximately 10 cM apart across the autosomes to identify QTL influencing the QUS traits. Age, sex, and other significant covariates were simultaneously adjusted. Heritability estimates (h²) for the QUS traits ranged from 0.42 to 0.57. Significant evidence for a QTL influencing BUA was found on chromosome 11p15 near marker D11S902 (LOD = 3.11). Our results provide additional evidence for a QTL on chromosome 11p that harbors a potential candidate gene(s) related to BUA and bone metabolism.