Contact patterns in a high school: a comparison between data collected using wearable sensors, contact diaries and friendship surveys

Given their importance in shaping social networks and determining how information or diseases propagate in a population, human interactions are the subject of many data collection efforts. To this aim, different methods are commonly used, from diaries and surveys to wearable sensors. These methods show advantages and limitations but are rarely compared in a given setting. As surveys targeting friendship relations might suffer less from memory biases than contact diaries, it is also interesting to explore how daily contact patterns compare with friendship relations and with online social links. Here we make progresses in these directions by leveraging data from a French high school: face-to-face contacts measured by two concurrent methods, sensors and diaries; self-reported friendship surveys; Facebook links. We compare the data sets and find that most short contacts are not reported in diaries while long contacts have larger reporting probability, with a general tendency to overestimate durations. Measured contacts corresponding to reported friendship can have durations of any length but all long contacts correspond to reported friendships. Online links not associated to reported friendships correspond to short face-to-face contacts, highlighting the different nature of reported friendships and online links. Diaries and surveys suffer from a low sampling rate, showing the higher acceptability of sensor-based platform. Despite the biases, we found that the overall structure of the contact network, i.e., the mixing patterns between classes, is correctly captured by both self-reported contacts and friendships networks. Overall, diaries and surveys tend to yield a correct picture of the structural organization of the contact network, albeit with much less links, and give access to a sort of backbone of the contact network corresponding to the strongest links in terms of cumulative durations

Estimating the epidemic risk using non-uniformly sampled contact data

Many datasets describing contacts in a population suffer from incompleteness due to population sampling and underreporting of contacts. Data-driven simulations of spreading processes using such incomplete data lead to an underestimation of the epidemic risk, and it is therefore important to devise methods to correct this bias. We focus here on a non-uniform sampling of the contacts between individuals, aimed at mimicking the results of diaries or surveys, and consider as case studies two datasets collected in different contexts. We show that using surrogate data built using a method developed in the case of uniform population sampling yields an improvement with respect to the use of the sampled data but is strongly limited by the underestimation of the link density in the sampled network. We put forward a second method to build surrogate data that assumes knowledge of the density of links within one of the groups forming the population. We show that it gives very good results when the population is strongly structured, and discuss its limitations in the case of a population with a weaker group structure. These limitations highlight the interest of measurements using wearable sensors able to yield accurate information on the structure and durations of contacts

Longitudinal falls data in Parkinson’s disease: feasibility of fall diaries and effect of attrition

Background: Identifying causes of falls for people with Parkinson’s disease has met with limited success. Prospective falls measurement using the “gold standard” approach is challenging. This paper examines the process and outcomes associated with longitudinal falls reporting in this population. Methods: Participants were recruited from ICICLE-GAIT (a collaborative study with ICICLE-PD; an incident cohort study). Monthly falls diaries were examined over 48 months for accuracy of data and rate of attrition. To further inform analysis, characteristics of participants with 36-month completed diaries were compared with those who did not complete diaries. Results: One hundred and twenty-one participants were included at baseline. By 12 months, falls diary data had reduced to 107 participants; to 81 participants by 36 months; and to 59 participants by 48 months. Key reasons for diary attrition were withdrawal from ICICLE-gait (n = 16) (13.2%), and noncompliance (n = 11) (9.1%). The only significant difference between the completed and non-completed diary groups was age at 36 months, with older participants being more likely to send in diaries. Conclusions: Prospective falls data is feasible to collect over the long term. Attrition rates are high; however, participants retained in the study are overall representative of the total falls diary cohort

Social contact structures and time use patterns in the Manicaland Province of Zimbabwe.

BACKGROUND: Patterns of person-to-person contacts relevant for infectious diseases transmission are still poorly quantified in Sub-Saharan Africa (SSA), where socio-demographic structures and behavioral attitudes are expected to be different from those of more developed countries. METHODS AND FINDINGS: We conducted a diary-based survey on daily contacts and time-use of individuals of different ages in one rural and one peri-urban site of Manicaland, Zimbabwe. A total of 2,490 diaries were collected and used to derive age-structured contact matrices, to analyze time spent by individuals in different settings, and to identify the key determinants of individuals' mixing patterns. Overall 10.8 contacts per person/day were reported, with a significant difference between the peri-urban and the rural site (11.6 versus 10.2). A strong age-assortativeness characterized contacts of school-aged children, whereas the high proportion of extended families and the young population age-structure led to a significant intergenerational mixing at older ages. Individuals spent on average 67% of daytime at home, 2% at work, and 9% at school. Active participation in school and work resulted the key drivers of the number of contacts and, similarly, household size, class size, and time spent at work influenced the number of home, school, and work contacts, respectively. We found that the heterogeneous nature of home contacts is critical for an epidemic transmission chain. In particular, our results suggest that, during the initial phase of an epidemic, about 50% of infections are expected to occur among individuals younger than 12 years and less than 20% among individuals older than 35 years. CONCLUSIONS: With the current work, we have gathered data and information on the ways through which individuals in SSA interact, and on the factors that mostly facilitate this interaction. Monitoring these processes is critical to realistically predict the effects of interventions on infectious diseases dynamics

The Sleep Or Mood Novel Adjunctive therapy (SOMNA) trial: a study protocol for a randomised controlled trial evaluating an internet-delivered cognitive behavioural therapy program for insomnia on outcomes of standard treatment for depression in men

BACKGROUND: Insomnia is a significant risk factor for depression onset, can result in more disabling depressive illness, and is a common residual symptom following treatment cessation that can increase the risk of relapse. Internet-based cognitive behavioural therapy for insomnia has demonstrated efficacy and acceptability to men who are less likely than women to seek help in standard care. We aim to evaluate whether internet delivered cognitive behavioural therapy for insomnia as an adjunct to a standard depression therapeutic plan can lead to improved mood outcomes.METHODS/DESIGN: Male participants aged 50 years or more, meeting Diagnostic and Statistical Manual of Mental Disorders criteria for current Major Depressive Episode and/or Dysthymia and self-reported insomnia symptoms, will be screened to participate in a single-centre double-blind randomised controlled trial with two parallel groups involving adjunctive internet-delivered cognitive behavioural therapy for insomnia and an internet-based control program. The trial will consist of a nine-week insomnia intervention period with a six-month follow-up period. During the insomnia intervention period participants will have their depression management coordinated by a psychiatrist using standard guideline-based depression treatments. The study will be conducted in urban New South Wales, Australia, where 80 participants from primary and secondary care and direct from the local community will be recruited. The primary outcome is change in the severity of depressive symptoms from baseline to week 12. DISCUSSION: This study will provide evidence on whether a widely accessible, evidence-based, internet-delivered cognitive behavioural therapy for insomnia intervention can lead to greater improvements than standard treatment for depression alone, in a group who traditionally do not readily access psychotherapy. The study is designed to establish effect size, feasibility and processes associated with implementing e-health solutions alongside standard clinical care, to warrant undertaking a larger more definitive clinical trial.Trial registration: Australian and New Zealand Clinical Trials Registry ACTRN12612000985886.The study is supported by beyondblue: the national depression and anxiety initiative National Priority Driven Research Program and funded through a donation from the Movember Foundation

Diary reports of concerns in mothers of infant siblings of children with autism across the first year of life

We examined the home-based concerns reported by mothers of infant siblings of children with autism across the first year of life. At all three ages measured, mothers of high-risk infants were significantly more likely than mothers of low-risk infants to report language, social communication, and restricted and repetitive behavior concerns but were not more likely to report general, medically based concerns. At 6 and 9 months of age, maternal concerns were poorly related to infant or family variables. At 12 months of age, there were moderate correlations between maternal concerns and infant behavior, and concerns were associated with the proband's autism symptoms and mothers' concurrent depressive symptoms. These findings highlight the need to examine high-risk infants' development in the family context.R21 DC 08637 - NIDCD NIH HHS; R01-DC010290 - NIDCD NIH HHS; AS1323 - Autism Speaks; R21 DC008637 - NIDCD NIH HHS; R01 DC010290 - NIDCD NIH HH

Nausea and vomiting in pregnancy (NVP) is not just 'Morning Sickness' : data from a prospective cohort study

Background: Nausea and vomiting in pregnancy is usually called ‘morning sickness’. This is felt by sufferers to trivialise the condition. Symptoms have been described as occurring both before and after noon, but daily symptom patterns have not been clearly described and statistically modelled to enable the term ‘morning sickness’ to be accurately analysed. Aim: To describe the daily variation in nausea and vomiting symptoms during early pregnancy in a group of sufferers. Design and setting: A prospective cohort study of females recruited from 15 May 2014 to 17 February 2017 by Swiss Precision Diagnostics (SPD) Development Company Limited, which was researching hormone levels in early pregnancy and extended its study to include the description of pregnancy symptoms. Method: Daily symptom diaries of nausea and vomiting were kept by females who were trying to conceive. They also provided daily urine samples, which when analysed enabled the date of ovulation to be determined. Data from 256 females who conceived during the first month of the study are included in this article. Daily symptom patterns and changes in daily patterns by week of pregnancy were modelled. Functional data analysis was used to produce estimated symptom probability functions. Results: There was a peak probability of nausea in the morning, a lower but sustained probability of nausea throughout the day, and a slight peak in the evening. Vomiting had a defined peak incidence in the morning. Conclusion: Referring to nausea and vomiting in pregnancy as simply ‘morning sickness’ is inaccurate, simplistic, and therefore unhelpful

Content Creation Online

Presents findings from surveys conducted between March and May 2003. Measures the extent to which American adults have used the Internet to publish their thoughts, respond to others, post pictures, and share files

Intake of game birds in the UK:assessment of the contribution to the dietary intake of lead by women of childbearing age and children

AbstractObjectiveConcern has recently been expressed about Pb levels in Pb-shot game meat. Our aim was to determine the consumption of game birds in a representative sample population in the UK, and in children and women of childbearing age in particular.DesignPopulation-based cross-sectional cohort study. Data from 4 d diet diaries from the UK National Diet and Nutrition Survey (NDNS; 2008–2010) were extracted to analyse data on game bird consumption in the sample population, in women of childbearing age (15–45 years old) and in children ≤6 years old.SettingHome-based study in representative areas of the UK.SubjectsParticipants in the NDNS (2008–2010; n 2126, age 1·5 to &gt;65 years).ResultsFifty-eight participants (2·7 %) reported eating game birds. The mean intake was 19·5 (sd 18·1) g/d (median 15·6, range 1·3–92·9 g/d). In women of childbearing age (15–45 years), 11/383 (2·9 %) reported eating game birds, with a mean intake of 22·4 (sd 25·8) g/d (median 15·6, range 2·0–92·9 g/d). In children aged ≤6 years old, 3/342 (0·9 %) were reported as eating game birds, with a mean intake of 6·8 (sd 9·7) g/d (median 2·4, range 1·3–23·2 g/d).ConclusionsThe prevalence of consumption of game birds by women of childbearing age and children ≤6 years old was relatively low and intakes were small. However, any exposure to Pb in these two groups is undesirable. As are uncertainties about the ability of the diet diary method to capture the consumption of food items that are infrequently consumed, alternative methods of capturing these data should be used in future studies.</jats:sec