ABSTRACT

The Albero study analyzes the personal transitions of a cohort of high school students at the end of their studies. The data consist of (a) the longitudinal social network of the students, before (n = 69) and after (n = 57) finishing their studies; and (b) the longitudinal study of the personal networks of each of the participants in the research. The two observations of the complete social network are presented in two matrices in Excel format. For each respondent, two square matrices of 45 alters of their personal networks are provided, also in Excel format. For each respondent, both psychological sense of community and frequency of commuting is provided in a SAV file (SPSS). The database allows the combined analysis of social networks and personal networks of the same set of individuals.

INTRODUCTION

Ecological transitions are key moments in the life of an individual that occur as a result of a change of role or context. This is the case, for example, of the completion of high school studies, when young people start their university studies or try to enter the labor market. These transitions are turning points that carry a risk or an opportunity (Seidman & French, 2004). That is why they have received special attention in research and psychological practice, both from a developmental point of view and in the situational analysis of stress or in the implementation of preventive strategies.

The data we present in this article describe the ecological transition of a group of young people from Alcala de Guadaira, a town located about 16 kilometers from Seville. Specifically, in the “Albero” study we monitored the transition of a cohort of secondary school students at the end of the last pre-university academic year. It is a turning point in which most of them began a metropolitan lifestyle, with more displacements to the capital and a slight decrease in identification with the place of residence (Maya-Jariego, Holgado & Lubbers, 2018).

Normative transitions, such as the completion of studies, affect a group of individuals simultaneously, so they can be analyzed both individually and collectively. From an individual point of view, each student stops attending the institute, which is replaced by new interaction contexts. Consequently, the structure and composition of their personal networks are transformed. From a collective point of view, the network of friendships of the cohort of high school students enters into a gradual process of disintegration and fragmentation into subgroups (Maya-Jariego, Lubbers & Molina, 2019).

These two levels, individual and collective, were evaluated in the “Albero” study. One of the peculiarities of this database is that we combine the analysis of a complete social network with a survey of personal networks in the same set of individuals, with a longitudinal design before and after finishing high school. This allows combining the study of the multiple contexts in which each individual participates, assessed through the analysis of a sample of personal networks (Maya-Jariego, 2018), with the in-depth analysis of a specific context (the relationships between a promotion of students in the institute), through the analysis of the complete network of interactions. This potentially allows us to examine the covariation of the social network with the individual differences in the structure of personal networks.

PARTICIPANTS

The social network and personal networks of the students of the last two years of high school of an institute of Alcala de Guadaira (Seville) were analyzed. The longitudinal follow-up covered approximately a year and a half. The first wave was composed of 31 men (44.9%) and 38 women (55.1%) who live in Alcala de Guadaira, and who mostly expect to live in Alcala (36.2%) or in Seville (37.7%) in the future. In the second wave, information was obtained from 27 men (47.4%) and 30 women (52.6%).

DATE STRUCTURE AND ARCHIVES FORMAT

The data is organized in two longitudinal observations, with information on the complete social network of the cohort of students of the last year, the personal networks of each individual and complementary information on the sense of community and frequency of metropolitan movements, among other variables.

Social network

The file “Red_Social_t1.xlsx” is a valued matrix of 69 actors that gathers the relations of knowledge and friendship between the cohort of students of the last year of high school in the first observation. The file “Red_Social_t2.xlsx” is a valued matrix of 57 actors obtained 17 months after the first observation.

The data is organized in two longitudinal observations, with information on the complete social network of the cohort of students of the last year, the personal networks of each individual and complementary information on the sense of community and frequency of metropolitan movements, among other variables.

In order to generate each complete social network, the list of 77 students enrolled in the last year of high school was passed to the respondents, asking that in each case they indicate the type of relationship, according to the following values: 1, “his/her name sounds familiar"; 2, "I know him/her"; 3, "we talk from time to time"; 4, "we have good relationship"; and 5, "we are friends." The two resulting complete networks are represented in Figure 2. In the second observation, it is a comparatively less dense network, reflecting the gradual disintegration process that the student group has initiated.

Personal networks

Also in this case the information is organized in two observations. The compressed file “Redes_Personales_t1.csv” includes 69 folders, corresponding to personal networks. Each folder includes a valued matrix of 45 alters in CSV format. Likewise, in each case a graphic representation of the network obtained with Visone (Brandes and Wagner, 2004) is included. Relationship values range from 0 (do not know each other) to 2 (know each other very well).

Second, the compressed file “Redes_Personales_t2.csv” includes 57 folders, with the information equivalent to each respondent referred to the second observation, that is, 17 months after the first interview. The structure of the data is the same as in the first observation.

Sense of community and metropolitan displacements

The SPSS file “Albero.sav” collects the survey data, together with some information-summary of the network data related to each respondent. The 69 rows correspond to the 69 individuals interviewed, and the 118 columns to the variables related to each of them in T1 and T2, according to the following list:

 • Socio-economic data.


 • Data on habitual residence.


 • Information on intercity journeys.


 • Identity and sense of community.


 • Personal network indicators.


 • Social network indicators.

DATA ACCESS

Social networks and personal networks are available in CSV format. This allows its use directly with UCINET, Visone, Pajek or Gephi, among others, and they can be exported as Excel or text format files, to be used with other programs.

The visual representation of the personal networks of the respondents in both waves is available in the following album of the Graphic Gallery of Personal Networks on Flickr: .

In previous work we analyzed the effects of personal networks on the longitudinal evolution of the socio-centric network. It also includes additional details about the instruments applied. In case of using the data, please quote the following reference:

Maya-Jariego, I., Holgado, D. & Lubbers, M. J. (2018). Efectos de la estructura de las redes personales en la red sociocéntrica de una cohorte de estudiantes en transición de la enseñanza secundaria a la universidad. Universitas Psychologica, 17(1), 86-98. https://doi.org/10.11144/Javeriana.upsy17-1.eerp

The English version of this article can be downloaded from: https://tinyurl.com/yy9s2byl

CONCLUSION

The database of the “Albero” study allows us to explore the co-evolution of social networks and personal networks. In this way, we can examine the mutual dependence of individual trajectories and the structure of the relationships of the cohort of students as a whole. The complete social network corresponds to the same context of interaction: the secondary school. However, personal networks collect information from the different contexts in which the individual participates. The structural properties of personal networks may partly explain individual differences in the position of each student in the entire social network. In turn, the properties of the entire social network partly determine the structure of opportunities in which individual trajectories are displayed.

The longitudinal character and the combination of the personal networks of individuals with a common complete social network, make this database have unique characteristics. It may be of interest both for multi-level analysis and for the study of individual differences.

ACKNOWLEDGEMENTS

The fieldwork for this study was supported by the Complementary Actions of the Ministry of Education and Science (SEJ2005-25683), and was part of the project “Dynamics of actors and networks across levels: individuals, groups, organizations and social settings” (2006 -2009) of the European Science Foundation (ESF). The data was presented for the first time on June 30, 2009, at the European Research Collaborative Project Meeting on Dynamic Analysis of Networks and Behaviors, held at the Nuffield College of the University of Oxford.

REFERENCES

Brandes, U., & Wagner, D. (2004). Visone - Analysis and Visualization of Social Networks. In M. Jünger, & P. Mutzel (Eds.), Graph Drawing Software (pp. 321-340). New York: Springer-Verlag.

Maya-Jariego, I. (2018). Why name generators with a fixed number of alters may be a pragmatic option for personal network analysis. American Journal of

The full text of this article can be freely accessed on the publisher's website.

Data from a prospective observational longitudinal study examining the relationship between sole hemorrhages or sole ulcers in peak to mid-lactation and time standing during the weeks around calving. A convenience sample of 8 dairy cattle herds were visited every other week, and animals without previous severe horn lesions and deemed sound at 4 to 8 wk before calving were enrolled. Standing behavior was measured with data loggers attached to a rear leg, and standing time and duration of the longest standing bout were determined for each cow. Standing behavior was summarized into 3 periods: before (d -14 to -2), around (d -1 to 1), and after (d 2 to 14) calving. Average daily standing time and average daily longest standing bout were determined for each cow and period.

When traditional approaches for weight loss, such as diet, exercise, and medications, fail as effective treatments for obesity, bariatric surgical procedures that restrict stomach size or lead to altered absorption of nutrients may be performed. While these procedures often result in significant, sustained weight loss, the benefits must be balanced against the short- and long-term risks of bariatric surgery. The Longitudinal Assessment of Bariatric Surgery (LABS) observational study was established by the LABS Consortium to assess the risks and health benefits associated with bariatric surgery and to identify aspects of the procedures and patient characteristics associated with optimal outcomes. The study is organized into three phases: LABS-1, which evaluates the short-term safety of bariatric surgery; LABS-2, which evaluates the longer-term safety and efficacy of bariatric surgery, in addition to examining patient characteristics associated with short- and intermediate-term outcomes; and LABS-3, which examines the psychosocial, quality-of-life, and health economics aspects of obesity, as well as the mechanisms of obesity-related diseases.

The LABS-1 study enrolled patients at least 18 years of age who underwent bariatric surgical procedures between March 2005 and December 2007 at LABS surgical centers. Participants underwent a pre-operative evaluation, during which data was collected on height, weight, blood pressure, comorbid conditions, and physical examination. Participant outcomes were recorded post-operatively. The primary outcome measure was a composite endpoint of any of the following occurring within 30 days of surgery: death; deep vein thrombosis (DVT) or venothromboembolism (VTE); reintervention using percutaneous, endoscopic, or operative techniques; or failure to discharge from the hospital. Of the 4776 patients who had a first-time procedure, over half had at least two co-morbid conditions. The 30-day mortality rate for Roux-en-y gastric bypass or laparoscopic adjustable gastric banding was 0.3%; 4.3% of participants had at least one major adverse outcome. The LABS-1 study showed that the short-term risk of death and adverse outcome after bariatric surgery was low, particularly when contrasted with patient characteristics.

Following conclusion of the LABS-1 study, the LABS-2 study was initiated to examine the longer-term safety, outcomes, and durability of health changes of bariatric surgery. The primary objectives of the LABS-2 study were to determine weight, medical, surgical, and behavioral outcomes, including incidence and remission of co-morbid conditions, and to evaluate patient, procedure, and other characteristics that were associated with these outcomes. The cohort included patients who underwent bariatric surgery at LABS clinical centers through 2009.

Clinical assessments and detailed interviews and questionnaires are administered at several post-operative time points (30 days, 6 months, 12 months following surgery, and annually thereafter) to assess risks of surgery and changes in clinical, metabolic, and psychosocial characteristics in patients following bariatric surgery. Detailed data about the surgical procedure and peri- and post-operative care are also collected to determine if components of the surgical procedure, care, and/or clinical/demographic patient characteristics are associated with post-operative risks and changes in patient status.

An ancillary study from LABS-2 regarding psychosocial issues associated with weight loss was conducted at two of the LABS study centers, and a set of control participants were recruited from primary care practices outside of the LABS consortium. The overall duration of this ancillary study was 48 months with the goal of assessing changes in sexual function and sex hormones in the two groups at predetermined follow-up visits.

An ancillary study from LABS-3 regarding psychosocial issues associated with bariatric surgery was conducted at three of the LABS study centers with participants that were previously enrolled in LABS-1 and LABS-2. This prospective cohort ancillary study aimed to understand the mental health impacts of bariatric surgery and changes in mental health outcomes over a 7-year follow-up period. Data were collected on psychosocial issues such as eating disorders, substance abuse, affective disorders, and cognitive function.

The current data package available includes full data from LABS-1 and LABS-2, and ancillary data from LABS-2 and LABS-3.

Supplementary Material 3.

The Project on Human Development in Chicago Neighborhoods (PHDCN) was a large-scale, interdisciplinary study of how families, schools, and neighborhoods affect child and adolescent development. One component of the PHDCN was the Longitudinal Cohort Study, which was a series of coordinated longitudinal studies that followed over 6,000 randomly selected children, adolescents, and young adults, and their primary caregivers over time to examine the changing circumstances of their lives, as well as the personal characteristics, that might lead them toward or away from a variety of antisocial behaviors. Numerous measures were administered to respondents to gauge various aspects of human development, including individual differences, as well as family, peer, and school influences. One of the measures composing the Longitudinal Cohort Study was the Home Observation for Measurement of the Environment (HOME) inventory. The HOME inventory sought to observe the developmental environment in which children belonging to the Longitudinal Cohort Study sample were raised. The HOME inventory was designed to capture the absence or presence of certain cognitive stimuli, including varied learning experiences and diverse educational materials. The HOME inventory also measured the extent and nature of the interactions that occurred between the subject and his or her primary caregiver, the subject and the subject's father (if the father was not the primary caregiver), and the subject and other family members. The PHDCN version of the HOME inventory also assessed the physical conditions in and around the respondent's home, taking careful note of the layout of the streets and buildings comprising the neighborhood.

The dataset contains the two Stata V17 files on which the article in World Development (2014) with the same title as the dataset is based. It also includes the Stata computer codes (do files) and a one-page Word document on how to run the datasets

Background: Low serum 25-hydroxyvitamin D (25(OH)D) levels have consistently been associated with hypertension. During the last decades there has been an unexplained reduction in blood pressure (BP) in Western countries. We therefore examined the relation between serum 25(OH)D and BP in the 7th survey of the Tromsø study 2015/2016. Methods: Blood pressure and serum 25(OH)D were measured and life-style factors registered in 15,951 subjects not using BP medication. Results: In unadjusted analyses there was a significant negative association between serum 25(OH)D and systolic and diastolic BP that disappeared after adjusting for relevant confounders. This finding is in contrast to our previous reports on 25(OH)D and BP. We therefore cross-sectionally re-analyzed non-smoking (due to interference by smoking in the 25(OH)D assay) subjects not using BP medication from the 4th survey in 1994/1995 (n = 4108), 6th survey in 2007/2008 (n = 7553) and 7th survey 2015/2016 (n = 13,413). Adjusting for age and BMI, there were significant inverse relations between BP and 25(OH)D in the 4th, to a lesser degree in the 6th, and none in the 7th survey. For males the age- and BMI-adjusted differences in systolic BP between those with serum 25(OH)D < 25 nmol/L versus serum 25(OH)D > 100 nmol/L were 6.2 mmHg, 4.1 mmHg and −0.1 mmHg, for the 4th, 6th and 7th surveys, respectively. Conclusions: Concomitant with a substantial reduction in BP from 1994 to 2015, there has been a loss of relation between 25(OH)D and BP which is hard to explain.

Initial data analysis (IDA) is the part of the data pipeline that takes place between the end of data retrieval and the beginning of data analysis that addresses the research question. Systematic IDA and clear reporting of the IDA findings is an important step towards reproducible research. A general framework of IDA for observational studies includes data cleaning, data screening, and possible updates of pre-planned statistical analyses. Longitudinal studies, where participants are observed repeatedly over time, pose additional challenges, as they have special features that should be taken into account in the IDA steps before addressing the research question. We propose a systematic approach in longitudinal studies to examine data properties prior to conducting planned statistical analyses. In this paper we focus on the data screening element of IDA, assuming that the research aims are accompanied by an analysis plan, meta-data are well documented, and data cleaning has already been performed. IDA data screening comprises five types of explorations, covering the analysis of participation profiles over time, evaluation of missing data, presentation of univariate and multivariate descriptions, and the depiction of longitudinal aspects. Executing the IDA plan will result in an IDA report to inform data analysts about data properties and possible implications for the analysis plan—another element of the IDA framework. Our framework is illustrated focusing on hand grip strength outcome data from a data collection across several waves in a complex survey. We provide reproducible R code on a public repository, presenting a detailed data screening plan for the investigation of the average rate of age-associated decline of grip strength. With our checklist and reproducible R code we provide data analysts a framework to work with longitudinal data in an informed way, enhancing the reproducibility and validity of their work.

Subset from COVID-19 Dataset from https://zenodo.org/record/3766350#.YVcfyTFBxgA. Used as reference for a publication dealing with synthetic patient cohort generation.

Important statistical issues pervade the evaluation of training programs’ effects for unemployed people. In particular the fact that offered wages are observed and well-defined only for subjects who are employed (truncation by death), and the problem that information on the individuals’ employment status and wage can be lost over time (attrition) raise methodological challenges for causal inference. We present an extended framework for simultaneously addressing the aforementioned problems, and thus answering important substantive research questions, in training evaluation observational studies with covariates, a binary treatment and longitudinal information on employment status and wage, which may be missing due to the lost to follow-up. There are two key features of this framework: we use principal stratification to properly define the causal effects of interest and to deal with non-ignorable missingness, and we adopt a Bayesian approach for inference. The proposed framework allows us to also at least partially answer an open issue in economics: the assessment of the trend of reservation wage over the duration of unemployment. We apply our framework to evaluate causal effects of foreign language training programs in Luxembourg, using administrative data on the labor force (IGSS-ADEM dataset). Our findings might be an incentive for the employment agencies to better design and implement future language training programs.

The TODAY (Treatment Options for Type 2 Diabetes in Adolescents and Youth) study was a multi-center randomized clinical trial (2004-2011). Youth aged 10-17 years diagnosed with type 2 diabetes (T2D) for less than 2 years were enrolled. The trial compared the efficacy of three treatment arms: (1) metformin alone, (2) metformin plus rosiglitazone, and (3) metformin plus an intensive lifestyle intervention. The TODAY trial concluded in February 2011 and was followed by TODAY2 (2011-2020), an observational longitudinal study to continue follow-up of the TODAY cohort to document the progression of diabetes and its complications and related comorbidities.

In the last year of the TODAY study, the cohort was assessed by echocardiography. A follow-up echocardiogram was completed 5 years later during the TODAY2 study. During TODAY2, the study also collected comparative echocardiogram control data in individuals without diabetes and hypertension, and also performed a one-time collection of data and blood for storage of serum and plasma in these consented control participants.

The purpose of this study was to evaluate the long-term organizational transition of the Chicago Police Department (CPD) to a community policing model. The Chicago Alternative Policing Strategy (CAPS) was an ambitious plan to reorganize the CPD, restructure its management, redefine its mission, and forge a new relationship between police and city residents. This evaluation of the CAPS program included surveys of police officers, residents, and program activists. In addition, observational data were collected from beat meetings, and aggregate business establishment and land-use data were added to describe the police beats and districts.

The PROFILE study is a longitudinal observational study of patients with Idiopathic Pulmonary Fibrosis and Nonspecific Interstitial Pneumonitis. Patients were recruited to the study within 6 months of diagnosis and followed up for three years.

Evidence on social stimuli associated with mental health is based mostly on self-reported health measures. These datasets comprise data to examine prospective associations between social connectedness and clinical diagnosis of depression and of anxiety. This dataset was constructed by merging longitudinal observational data with health insurance data comprising medical information on diagnosis of depression and anxiety. Not imputed and imputed [imputations using chained equations (with 10 sets of imputed data)] datasets are provided. Stata script to replicate analyses is attached.

Causal inference with observational longitudinal data and time-varying exposures is complicated due to the potential for time-dependent confounding and unmeasured confounding. Most causal inference methods that handle time-dependent confounding rely on either the assumption of no unmeasured confounders or the availability of an unconfounded variable that is associated with the exposure (e.g., an instrumental variable). Furthermore, when data are incomplete, validity of many methods often depends on the assumption of missing at random. We propose an approach that combines a parametric joint mixed-effects model for the study outcome and the exposure with g-computation to identify and estimate causal effects in the presence of time-dependent confounding and unmeasured confounding. G-computation can estimate participant-specific or population-average causal effects using parameters of the joint model. The joint model is a type of shared parameter model where the outcome and exposure-selection models share common random effect(s). We also extend the joint model to handle missing data and truncation by death when missingness is possibly not at random. We evaluate the performance of the proposed method using simulation studies and compare the method to both linear mixed-effects models and fixed-effects models combined with g-computation as well as to targeted maximum likelihood estimation. We apply the method to an epidemiologic study of vitamin D and depressive symptoms in older adults and include code using SAS PROC NLMIXED software to enhance the accessibility of the method to applied researchers.

Abstract copyright UK Data Service and data collection copyright owner.

The Smart Energy Research Lab (SERL) delivers a unique energy data resource to the UK research community that enables a broad range of multi-disciplinary, socio-technical research relating to energy consumption in domestic buildings.

The SERL Observatory is transforming Great Britain's energy research through the long-term provision of high quality, high-resolution energy data that provides a reliable evidence base for intervention, observational and longitudinal studies across the socio-technical spectrum.

The goals of the Smart Energy Research Lab are to provide:

• A trusted data resource for researchers to utilise large-scale, high-resolution energy data
• An effective mechanism for collecting and linking energy data with other contextual data
• High quality data management to ensure fit-for-purpose data are provisioned to researchers

Participant recruitment began in August 2019. Approximately 1,700 participants were recruited from central and southern England and from Wales as part of a pilot study that tested different recruitment strategies. The second recruitment wave took place in August-September 2020, and the third wave at the start of 2021. SERL recruited over 13,000 households which are regionally representative across England, Scotland and Wales. Recruitment is also designed to be representative of each Index of Multiple Deprivation (IMD) quintile; an area-based relative measure of deprivation.

For the latest edition (released in May 2024), all SERL data up to and including 31st December 2023 were made available. Users should note that this is the 6th edition of SERL data that has been released, though the citation may refer to the 7th edition.

All code provided with the data is now managed on the SERL GitHub website.

Smart meter data:

• Daily and half-hourly energy (electricity and gas) consumption data
• Tariff data
• Additional smart meter technical data

Contextual data:

• SERL survey (initial) completed by participant households on sign-up providing data on household information and building characteristics.
• Energy Performance Certificate (EPC) data
• Weather data
• SERL Covid-19 survey: sent to wave 1 participants in May 2020 to understand their circumstances during the first lockdown
• SERL survey (Follow-up 2023): sent to all active participants in early 2023 to investigate the impact of rapidly rising energy costs in 2022/2023

SERL data will be updated and made available to researchers on a quarterly basis. SERL is an evolving data resource and thus new editions of the data might include:

• additional records – more smart meter data, since the previous edition
• additional participants – more participants recruited since the previous release
• additional variables – where new variables become available to SERL

Further information about SERL can be found on serl.ac.uk and in the associated documentation. The 'Key Documents' section of the SERL website, which links to all publications that use SERL data, can be found at serl.ac.uk/key-documents. If you do not see your SERL-data publication listed, please contact the SERL team via info@serl.ac.uk.

For the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 data users should note that neither the European Commission nor the European Centre for Medium-Range Weather Forecasts will be held responsible for any use that may be made of the Copernicus information or data it contains. The Energy Performance of Buildings Data is also included and users must read and abide by the Copyright Information Notice, provided by the Department for Levelling Up, Housing and Communities, that covers the use of Royal Mail information and non-address data provided under the Open Government Licence v3.0.

For the latest edition (released in November 2024), all SERL smart meter and climate data have been updated to June 2024. Users should note that this is the 7th edition of SERL data that has been released, though the citation may refer to the 8th edition.

Main Topics:

The SERL Observatory panel provides data primarily relating to energy demand and consumption in domestic buildings in Great Britain.

Born in Scotland is an ongoing observational longitudinal study set to capture a contemporary and representative cohort of mothers in Scotland and provide a valuable research resource to assess current clinical issues and health disparities and investigate the drivers of long-term maternal and child wellbeing. The current pilot study is open to recruitment and is testing consent models. The scale-up study intends to include 100,000 pregnant women and their children, constituting a diverse, flexible, and nationally representative maternity cohort. It is embedded within the NHS services, capitalising on capturing routinely collected data and biological samples, and allowing linkage to additional clinical and demographic data through the unique Community Health Index (CHI) number.

The pilot study currently targets all women aged 18-50 years old, living in Edinburgh and the Lothians and the Borders, and who are planning to give birth in Scotland, offering recruitment during any of the routine antenatal booking appointments. Data from the participants is extracted from the electronic maternity records, neonatal units, and clinical and diagnostic results. Biological samples are retrieved from hospital laboratories using samples that would otherwise be discarded after clinical use or collected at birth. The aim is to use the cohort to link to future maternal and child health and social care records to address key research questions to improve maternal and child health in Scotland.

The Maternal Lifestyle Study (MLS) was the largest of the NIH longitudinal studies of children with prenatal cocaine exposure (PCE). MLS was a longitudinal multi-site observational study of the long-term effects of in-utero exposure to cocaine on child development. MLS was conducted at four geographically diverse, collaborating university centers (Wayne State University, University of Tennessee at Memphis, University of Miami, and Brown University). Participants were identified during the newborn period while in the hospital. The MLS began enrollment of a longitudinal birth cohort of 1,388 infant/mother dyads in 1993. Subjects in the follow-up were seen from 1 month of age through 16 years of age. The overall purpose of the study was to investigate the effects of drug use during pregnancy on acute neonatal events and long-term physical health, social, behavioral and neurodevelopmental outcomes.

Cholestasis, a rare condition involving a reduction or obstruction of bile flow from the liver to the small intestine, can cause significant growth problems, liver complications, the need for liver transplantation, and death. The four rare genetic disorders Alagille syndrome (ALGS), alpha-1 antitrypsin (a-1AT) deficiency, bile acid synthesis defects, and progressive familial intrahepatic cholestasis (PFIC) account for approximately 20% to 30% of all infant cases of cholestasis. Current knowledge concerning the etiology and outcomes of these diseases is limited. The Longitudinal Study of Genetic Causes of Intrahepatic Cholestasis (LOGIC) study is a longitudinal cohort study that was established by the Childhood Liver Disease Research and Education Network (ChiLDReN) to investigate the natural history and progression of these four genetic disorders.

Children and adults ages 6 months through 25 years who have been diagnosed with ALGS, a-1AT deficiency, bile acid synthesis defects, and PFIC are enrolled. Individuals who are siblings of a-A1T participants and have underlying disease with no evidence of liver involvement may also be enrolled. Participants will complete a baseline visit and give annual follow-up visits. Study visits involve review of clinical information, family history, and any treatments and their outcomes. A physical exam, laboratory tests, and radiologic and imaging evaluations will also be performed. In addition to these standard of care evaluations, participants will undergo neurodevelopment evaluations, DEXA scanning, hearing exams, and liver histology studies. The primary outcome measure is the evaluation of disease progression for each condition, which includes assessment of growth failure, worsening liver functions, developmental complications of portal high blood pressure, liver transplantation, and death. Jaundice, listing for liver transplantation, calculated pediatric end-stage liver disease (PELD) score or model for end-stage liver disease (MELD) score, health-related quality of life, growth, bone mineral density, and presence of hearing loss are assessed as secondary outcome measures.

The data package now includes analysis datasets from multiple publications.