An evidence-informed pedagogical approach to support professional identity formation in medical students: AMEE Guide No. 171.

There is a long and impressive scholarly history evidencing why it is important to address professional identity formation (PIF) in medical curricula. In this AMEE Guide, the authors present an evidence-informed pedagogical approach to assist educators in developing educational practices to foster a healthy PIF in medical students. The authors first describe the theoretical framework that underpin this approach. At the core of this framework is the recognition that, for a healthy PIF, students need to become aware that they have the autonomy, but also responsibility, to form their professional identity in a way that fits both their personality and their (future) professional role. In other words, students need to learn to navigate the interplay between socialization and subjectification. Next, the authors outline the six-step structure of their pedagogical approach, designed to help students: (1) undergo a PIF-related experience, (2) observe their responses to the experience, (3) externalize their reflections, (4) share their reflections, (5) broaden their perspective, and (6) explore their freedom of choice through experimentation. The authors also describe six conducive conditions to facilitate the implementation of the pedagogical approach. These conditions include (1) creating a setting that enables students to slow down, (2) adopting a longitudinal approach, (3) making it part of the formal curriculum, (4) refraining from grading, (5) establishing an interdisciplinary expert team, and (6) providing teacher training. The authors conclude that the theoretical framework leads to a coherent and consistent pedagogical approach that, when implemented according to the conducive conditions, enables students to gradually internalize the reflective process and help them to cultivate a reflective attitude towards their PIF.

The Effectiveness of Family Constellation Therapy in Improving Mental Health: A Systematic Review.

Family/systemic constellation therapy is a short-term group intervention aiming to help clients better understand and then change their conflictive experiences within a social system (e.g., family). The aim of the present systematic review was to synthetize the empirical evidence on the tolerability and effectiveness of this intervention in improving mental health. The PsycINFO, Embase, MEDLINE, ISI Web of Science, Psyndex, PsycEXTRA, ProQuest Dissertations & Theses, The Cochrane Library, Google Scholar, and an intervention-specific organization's databases were searched for quantitative, prospective studies published in English, German, Spanish, French, Dutch or Hungarian up until April 2020. Out of 4,197 identified records, 67 were assessed for eligibility, with 12 studies fulfilling inclusion criteria (10 independent samples; altogether 568 participants). Outcome variables were diverse ranging from positive self-image through psychopathology to perceived quality of family relationships. Out of the 12 studies, nine showed statistically significant improvement postintervention. The studies showing no significant treatment benefit were of lower methodological quality. The random-effect meta-analysis-conducted on five studies in relation to general psychopathology-indicated a moderate effect (Hedges' g of 0.531, CI: 0.387-0.676). Authors of seven studies also investigated potential iatrogenic effects and four studies reported minor or moderate negative effects in a small proportion (5-8%) of participants that potentially could have been linked to the intervention. The data accumulated to date point into the direction that family constellation therapy is an effective intervention with significant mental health benefits in the general population; however, the quantity and overall quality of the evidence is low.

La terapia de constelación sistémica/familiar es una intervención grupal a corto plazo orientada a ayudar a los pacientes a comprender mejor y a cambiar sus experiencias conflictivas dentro de un sistema social (p. ej.: la familia). El objetivo del presente análisis sistemático fue sintetizar las pruebas empíricas sobre la tolerabilidad y la eficacia de esta intervención en la mejora de la salud mental. Se buscó en PsycINFO, Embase, MEDLINE, ISI Web of Science, Psyndex, PsycEXTRA, ProQuest Dissertations & Theses, The Cochrane Library, Google Scholar y en bases de datos de una organización dedicada a las intervenciones para obtener estudios cuantitativos y prospectivos publicados en inglés, alemán, español, francés, holandés o húngaro hasta abril de 2020. Se identificaron 4197 documentos y se evaluó la elegibilidad de 67. Finalmente se determinó que 12 cumplían con los criterios de inclusión (10 muestras independientes; en total, 568 participantes). Los criterios de valoración fueron diversos y abarcaron desde una autoimagen positiva hasta la psicopatología y la calidad percibida de las relaciones familiares. De los 12 estudios, 9 demostraron mejoras estadísticamente significativas después de la intervención. Los estudios que no demostraron ningún beneficio significativo del tratamiento fueron de menor calidad metodológica. El metaanálisis de efectos aleatorios -realizado en 5 estudios en relación con la psicopatología general- indicaron un efecto moderado (g de Hedges de 0.531, CI: 0.387-0.676). Los autores de 7 estudios también investigaron los posibles efectos iatrogénicos, y en 4 estudios se informaron efectos negativos moderados o leves en una pequeña proporción (5-8%) de participantes que podrían haber estado ligados a la intervención. Los datos acumulados hasta la fecha señalan que la terapia de constelación familiar es una intervención eficaz con beneficios considerables para la salud mental en la población en general; sin embargo, la cantidad y la calidad general de las pruebas es baja.

MOLGENIS research: advanced bioinformatics data software for non-bioinformaticians.

MOTIVATION: The volume and complexity of biological data increases rapidly. Many clinical professionals and biomedical researchers without a bioinformatics background are generating big '-omics' data, but do not always have the tools to manage, process or publicly share these data. RESULTS: Here we present MOLGENIS Research, an open-source web-application to collect, manage, analyze, visualize and share large and complex biomedical datasets, without the need for advanced bioinformatics skills. AVAILABILITY AND IMPLEMENTATION: MOLGENIS Research is freely available (open source software). It can be installed from source code (see http://github.com/molgenis), downloaded as a precompiled WAR file (for your own server), setup inside a Docker container (see http://molgenis.github.io), or requested as a Software-as-a-Service subscription. For a public demo instance and complete installation instructions see http://molgenis.org/research.

Maternal high-dose folic acid during pregnancy and asthma medication in the offspring.

PURPOSE: Low-dose folic acid supplementation (0.5 mg) taken during pregnancy has been associated with an increased risk for childhood asthma. The effect of high-dose folic acid (5 mg) advised to women at risk for having a child with neural tube defect has not been assessed so far. Our aim was to investigate the effect of dispensed high-dose folic acid during pregnancy and asthma medication in the offspring. METHODS: We used data from the pregnancy database IADB.nl, which contains pharmacy-dispensing data of mothers and children from community pharmacies in the Netherlands from 1994 until 2011. The dispension of asthma medication in children exposed in utero to high-dose folic acid was compared with children who were not exposed to this high dose. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated. RESULTS: In 2.9% (N = 913) of the 39,602 pregnancies in the database, the mother was dispensed high-dose folic acid. Maternal high-dose folic acid was associated with an increased rate of asthma medication among children: recurrent asthma medication IRR = 1.14 (95%CI: 1.04-1.30) and recurrent inhaled corticosteroids IRR = 1.26 (95%CI: 1.07-1.47). Associations were clustered on the mother and adjusted for maternal age, maternal asthma medication, and dispension of benzodiazepines during pregnancy. CONCLUSION: Almost 3% of the children were prenatally exposed to high-dose folic acid. This study suggests that supplementation of high-dose folic acid during pregnancy might increase the risk of childhood asthma.

A Systemic Perspective on Organizations: International Experience with the Systemic Constellation Method.

A systemic perspective is considered helpful when facing complex organizational challenges, but its practical implementation may be challenging. A potential effective method that facilitates the practical application of a systemic perspective may be the Systemic Constellation method. This method aims to raise individuals' awareness of their social context and to render explicit their tacit knowledge relating to this social context. In recent decades, consultants, coaches, and other professionals, worldwide, have adopted this method, acquired through self-education. However, thus far, this method received only little attention from the scientific community and scientific evidence on the effectiveness of the method is limited. There is currently almost no data on professionals using the Systemic Constellation method within organizations or on how and when they apply it. This lack of insights impedes its scientific evaluation and quality monitoring. We collected data from 273 professionals who use this method. Our results confirmed the existence of a diverse and growing international community. Respondents reported that the primary advantage of using this method is its perceived effectiveness. They felt that the method could benefit from a stronger scientific foundation. Our results shed light on a potentially effective and feasible method for applying a systemic perspective within organizations and suggest directions for future research. Supplementary Information: The online version contains supplementary material available at 10.1007/s11213-023-09642-2.

Maternal use of folic acid supplements during pregnancy, and childhood respiratory health and atopy.

Previous studies have suggested possible adverse side-effects of maternal use of folic acid-containing supplements (FACSs) during pregnancy on wheeze and asthma in early childhood. We investigated the association between maternal use of FACSs and childhood respiratory health and atopy in the first 8 yrs of life. Data on maternal use of FACSs, collected during pregnancy, were available for 3,786 children participating in the Prevention and Incidence of Asthma and Mite Allergy birth cohort study. Questionnaire data on children's respiratory and allergic symptoms were collected annually and allergic sensitisation and bronchial hyperresponsiveness (BHR) were measured at 8 yrs of age. No overall (from 1 to 8 yrs of age) associations were observed between maternal use of FACSs and (frequent) asthma symptoms, wheeze, lower respiratory tract infection, frequent respiratory tract infection and eczema. Maternal folic acid use was associated with wheeze at 1 yr of age (prevalence ratio 1.20, 95% CI 1.04-1.39), but not with wheeze at later ages. Pre-natal exposure to FACSs was not associated with sensitisation and BHR. Apart from a small increased risk of early wheeze, we observed no adverse respiratory or allergic outcomes associated with pre-natal FACSs exposure in our study population.

Quantification of the energy gap in young overweight children. The PIAMA birth cohort study.

BACKGROUND: Overweight develops gradually as a result of a long term surplus on the balance between energy intake and energy expenditure. Aim of this study was to quantify the positive energy balance responsible for excess body weight gain (energy gap) in young overweight children. METHODS: Reported data on weight and height were used of 2190 Dutch children participating in the PIAMA birth cohort study. Accumulated body energy was estimated from the weight gain observed between age 2 and age 5-7. Energy gap was calculated as the difference in positive energy balance between children with and without overweight assuming an energy efficiency of 50%. RESULTS: Ten percent of the children were overweight at the age of 5-7 years. For these children, median weight gain during 4-years follow-up was 13.3 kg, as compared to 8.5 kg in the group of children who had a normal weight at the end of the study. A daily energy gap of 289-320 kJ (69-77 kcal) was responsible for the excess weight gain or weight maintenance in the majority of the children who were overweight at the age of 5-7 years. The increase in daily energy requirement to maintain the 4.8 kilograms excess weight gain among overweight children at the end of the study was approximately 1371 kJ. CONCLUSIONS: An energy gap of about 289-320 kJ per day over a number of years can make the difference between normal weight and overweight in young children. Closing the energy gap in overweight children can be achieved by relatively small behavior changes. However, much more effort is required to lose the excess weight gained.

Maternal smoking during pregnancy and childhood obesity: results from the CESAR Study.

Childhood obesity is a worldwide public health concern. Recent studies from high income countries have demonstrated associations between maternal smoking during pregnancy and children's excess body weight. We examine associations between maternal smoking during pregnancy and children's overweight or obesity, in six countries in the less affluent Central/Eastern European region. Questionnaire data were analysed, for 8,926 singleton children aged 9-12 years. Country-specific odds ratios for effects of maternal smoking during pregnancy on being overweight, and on obesity, were estimated using logistic regression. Heterogeneity between country-specific results, and mean effects (allowing for heterogeneity) were estimated. Positive associations between maternal smoking and overweight were seen in all countries but Romania. While not individually statistically significant, the mean odds ratio was 1.26 (95% CI 1.03-1.55), with no evidence of between-country heterogeneity. Obese children were few (2.7%), and associations between obesity and maternal smoking during pregnancy were more heterogeneous, with odds ratios ranging from 0.71 (0.32-1.57) in Poland to 5.49 (2.11-14.30) in Slovakia. Between-country heterogeneity was strongly related to average persons-per-room, a possible socioeconomic indicator, with stronger associations where households were less crowded. Estimates of dose-response relationships tended to be small and non-significant, even when pooled. Our results provide evidence of a link between maternal smoking in pregnancy and childhood overweight. Associations with obesity, though strong in some countries, were less consistent. Maternal smoking may confer an addition to a child's potential for obesity, which is more likely to be realised in affluent conditions.

Early daycare is associated with an increase in airway symptoms in early childhood but is no protection against asthma or atopy at 8 years.

RATIONALE: Daycare exposes young children to more infections early in life and may thereby prevent the development of asthma and allergy. OBJECTIVES: To prospectively study the effect of daycare on the development of asthma and allergic sensitization during the first 8 years of life. METHODS: In the Prevention and Incidence of Asthma and Mite Allergy birth cohort 3,963 newborn children were followed prospectively for 8 years. Daycare use and respiratory health were assessed yearly by questionnaires. At 8 years, sensitization to airborne allergens and airway responsiveness were measured. Daycare was defined as early (aged 0-2 yr), late (aged 2-4 yr), or none (no daycare before age 4 yr). Associations of daycare and/or older siblings with asthma symptoms (wheezing, shortness of breath, and inhaled steroids taken in the last year), airway responsiveness, and allergic sensitization were assessed in a longitudinal repeated-event analysis. MEASUREMENTS AND MAIN RESULTS: Children with early daycare had more wheezing in the first years of life, but less wheezing and steroid use between 4 and 8 years of age. At the age of 8 years, early daycare was not protective for asthma symptoms (adjusted odds ratio [aOR], 0.99; 95% confidence interval [CI], 0.74-1.32), allergic sensitization (aOR 0.86; 95% CI, 0.63-1.18), or airway hyperresponsiveness (aOR, 0.80; 95% CI, 0.57-1.14). The transient reduction in airway symptoms between age 4 and 8 years was only observed in children without older siblings. CONCLUSION: Early daycare is associated with an increase in airway symptoms until the age of 4 years, and fewer symptoms between the ages of 4 and 8 years. We found no protection against asthma symptoms, hyperresponsiveness, or allergic sensitization at the age of 8 years.

Differences in school environment, school policy and actions regarding overweight prevention between Dutch schools. A nationwide survey.

BACKGROUND: Schools are regarded as an important setting for the prevention of overweight. This study presents a nationally representative picture of the obesogenity of the school environment, the awareness of schools regarding overweight, and actions taken by the schools aiming at overweight prevention. In addition, differences between school levels were studied. METHODS: In 2006-2007, questionnaires were sent to all Dutch secondary schools (age group 12-18 years). Prevalences of the outcome variables were calculated for the schools in total and by school level. The association between school level and outcome variables were analysed by a log linear regression. RESULTS: Unhealthy foods and drinks are widely available at secondary schools. One third of the schools indicated that overweight has increased among students and half of the schools agreed that schools were (co)responsible for the prevention of overweight. Only 3% of the schools have a policy on overweight prevention. Small differences were observed between vocational education schools and higher education schools. The presence of vending machines did not differ by school level, but at vocational education schools, the content of the vending machines was less healthy. CONCLUSION: This study describes the current situation at schools which is essential for the development and evaluation of future overweight prevention policies and interventions. In general, secondary schools are not actively involved in overweight prevention and the nutritional environment at most schools could be improved. The small differences between school levels do not give reason for a differential approach for a certain school level for overweight prevention.

Comorbidities of obesity in school children: a cross-sectional study in the PIAMA birth cohort.

BACKGROUND: There is ample evidence that childhood overweight is associated with increased risk of chronic disease in adulthood. The aim of this study was to investigate associations between childhood overweight and common childhood health problems. METHODS: Data were used from a general population sample of 3960 8-year-old children, participating in the Dutch PIAMA birth cohort study. Weight and height, measured by the investigators, were used to define BMI status (thinness, normal weight, moderate overweight, obesity). BMI status was studied cross-sectionally in relation to the following parental reported outcomes: a general health index, GP visits, school absenteeism due to illness, health-related functional limitations, doctor diagnosed respiratory infections and use of antibiotics. RESULTS: Obesity was significantly associated with a lower general health score, more GP visits, more school absenteeism and more health-related limitations, (adjusted odds ratios around 2.0 for most outcomes). Obesity was also significantly associated with bronchitis (adjusted odds ratio (aOR) and 95% confidence intervals (95%CI): 5.29 (2.58;10.85) and with the use of antibiotics (aOR (95%CI): 1.79 (1.09;2.93)). Associations with flu/serious cold, ear infection and throat infection were positive, but not statistically significant. Moderate overweight was not significantly associated with the health outcomes studied. CONCLUSION: Childhood obesity is not merely a risk factor for disease in adulthood, but obese children may experience more illness and health related problems already in childhood. The high prevalence of the outcomes studied implies a high burden of disease in terms of absolute numbers of sick children.

Overweight and changes in weight status during childhood in relation to asthma symptoms at 8 years of age.

BACKGROUND: Asthma may be more prevalent in overweight children. However, how early overweight and changes in weight status during childhood affect the asthma risk is unclear. OBJECTIVES: To investigate overweight and changes in overweight status in children age 1 to 8 years in relation to asthma symptoms in childhood. METHODS: We studied 3756 children who participated in a large birth cohort study. The parents reported their children's weight and height, and wheeze, dyspnea, and prescription of inhaled corticosteroids in yearly questionnaires. Sensitization to inhalant allergens and bronchial hyperresponsiveness (BHR) were determined at 8 years. RESULTS: At 8 years, 275 children (7.3%) wheezed, 361 (9.6%) had dyspnea, and 268 (7.1%) had a prescription of inhaled corticosteroids in the preceding year. Children who had a persistent high body mass index (BMI, weight/height2) during childhood or a high BMI at 6 to 7 years had a significantly increased risk of dyspnea (adjusted odds ratio, 1.68; 95% CI, 1.18-2.39, for a high BMI at 6-7 years) and measured BHR (adjusted odds ratio, 1.66; 95% CI, 1.10-2.52) at 8 years. Children with a high BMI at a young age, but who developed a normal BMI at 6 to 7 years, did not have an increased risk of dyspnea or BHR at 8 years. BMI was not associated with sensitization. CONCLUSION: Children with a current high BMI are at increased risk to have dyspnea and BHR at 8 years. A high BMI at an earlier age is not related to an increased risk if the child has become normal weight at 6 to 7 years.

Implementing Individually Tailored Prescription of Physical Activity in Routine Clinical Care: Protocol of the Physicians Implement Exercise = Medicine (PIE=M) Development and Implementation Project.

BACKGROUND: The prescription of physical activity (PA) in clinical care has been advocated worldwide. This "exercise is medicine" (E=M) concept can be used to prevent, manage, and cure various lifestyle-related chronic diseases. Due to several challenges, E=M is not yet routinely implemented in clinical care. OBJECTIVE: This paper describes the rationale and design of the Physicians Implement Exercise = Medicine (PIE=M) study, which aims to facilitate the implementation of E=M in hospital care. METHODS: PIE=M consists of 3 interrelated work packages. First, levels and determinants of PA in different patient and healthy populations will be investigated using existing cohort data. The current implementation status, facilitators, and barriers of E=M will also be investigated using a mixed-methods approach among clinicians of participating departments from 2 diverse university medical centers (both located in a city, but one serving an urban population and one serving a more rural population). Implementation strategies will be connected to these barriers and facilitators using a systematic implementation mapping approach. Second, a generic E=M tool will be developed that will provide tailored PA prescription and referral. Requirements for this tool will be investigated among clinicians and department managers. The tool will be developed using an iterative design process in which all stakeholders reflect on the design of the E=M tool. Third, we will pilot-implement the set of implementation strategies, including the E=M tool, to test its feasibility in routine care of clinicians in these 2 university medical centers. An extensive learning process evaluation will be performed among clinicians, department managers, lifestyle coaches, and patients using a mixed-methods design based on the RE-AIM framework. RESULTS: This project was approved and funded by the Dutch grant provider ZonMW in April 2018. The project started in September 2018 and continues until December 2020 (depending on the course of the COVID-19 crisis). All data from the first work package have been collected and analyzed and are expected to be published in 2021. Results of the second work package are described. The manuscript is expected to be published in 2021. The third work package is currently being conducted in clinical practice in 4 departments of 2 university medical hospitals among clinicians, lifestyle coaches, hospital managers, and patients. Results are expected to be published in 2021. CONCLUSIONS: The PIE=M project addresses the potential of providing patients with PA advice to prevent and manage chronic disease, improve recovery, and enable healthy ageing by developing E=M implementation strategies, including an E=M tool, in routine clinical care. The PIE=M project will result in a blueprint of implementation strategies, including an E=M screening and referral tool, which aims to improve E=M referral by clinicians to improve patients' health, while minimizing the burden on clinicians.

Long-chain polyunsaturated fatty acids in breast milk and early weight gain in breast-fed infants.

The long-chain PUFA (LCPUFA) content of an infant's diet might affect early weight gain. In early trials on supplementation of formula feeding n-3 LCPUFA affected weight gain adversely. n-6 LCPUFA are thought to promote adipose tissue development and might be associated with higher weight gain. We studied the association between the natural n-3 and n-6 LCPUFA content of breast milk of Dutch women and weight and BMI gain of their breast-fed infants in the first year of life. The children in this study were enrolled in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study and were born in 1996-1997 in The Netherlands. Parents reported their child's weight and length in a questionnaire. Of a subgroup of the total population breast-milk samples were collected (n 244). The fatty acid composition of breast milk was determined by GLC and expressed as weight percentages. Linear regression was used for data analysis. Mean gain in weight, length and BMI per week from birth to 1 year of age was 119.5 (SD 16.1) g, 0.48 (SD 0.05) cm and 0.06 (SD 0.03) kg/m2, respectively. The associations between n-6 and n-3 LCPUFA in breast milk, and infant weight, length and BMI gain were weak and inconsistent. The n-3 and n-6 LCPUFA content in breast milk did not affect weight or BMI gain in the first year of life in breast-fed term infants.

Active recruitment and limited participant-load related to high participation in large population-based biobank studies.

OBJECTIVES: Insight into baseline participation rates and their determinants is crucial for designing future population-based biobank studies. We therefore conducted a systematic review and meta-analysis of baseline participation rates and their determinants in large longitudinal population-based biobank studies. STUDY DESIGN AND SETTING: We screened studies registered within the Public Population Project in Genomics and Society and in the Biobanking and Biomolecular Resources Research Infrastructure catalogues to find potentially eligible studies. We retrieved data with regard to participation rate, biobank design, performed measurements, and specific strategies for improving participation. We calculated weighted pooled proportions for each determinant using random-effects models. RESULTS: We included 25 studies (participation rates 5-96%). Participation rates were highest for studies involving face-to-face recruitment [82.6%; 95% confidence interval (CI): 72.2%, 90.9%], for studies in which participants were visited for an examination (77.5%; 95% CI: 64.0%, 88.6%) and for studies in which at maximum four measurements were performed (78.2%; 95% CI: 69.7%, 85.7%). Specific strategies to improve participation were not found to be associated with higher participation rates. CONCLUSION: Specific choices of recruitment methods and design have consequences for participation rates. These insights may help to increase participation in future studies, thereby enhancing the validity of their findings.

The LifeLines Cohort Study: a resource providing new opportunities for environmental epidemiology.

BACKGROUND: Lifelines is a prospective population-based cohort study investigating the biological, behavioral and environmental determinants of healthy ageing among 167,729 participants from the North East region of the Netherlands. The collection and geocoding of (history of) home and work addresses allows linkage of individual-level health data to detailed exposure data. We describe the reasons for choosing particular assessments of environmental exposures in LifeLines and consider the implications for future investigations. METHODS: Exposure to ambient air pollution and road traffic noise was estimated using harmonized models. Data on noise annoyance, perceived exposure to electromagnetic fields, perceived living environment, and neighborhood characteristics were collected with questionnaires. A comprehensive medical assessment and questionnaires were completed in order to assess determinants of health and well-being. Blood and urine samples were collected from all participants and genome wide association data are available for a subsample of 15,638 participants. RESULTS: Mean age was 45 years (standard deviation (SD) 13 years), and 59 % were female. Median levels of NO2 and PM10 were 15.7 (interquartile range (IQR) 4.9) µg/m(3) and 24.0 (IQR 0.6) µg/m(3) respectively. Median levels of daytime road traffic noise were 54.0 (IQR 4.2) dB(A). CONCLUSIONS: The combination of harmonized environmental exposures and extensive assessment of health outcomes in LifeLines offers great opportunities for environmental epidemiology. LifeLines aims to be a resource for the international scientific community.

Representativeness of the LifeLines Cohort Study.

BACKGROUND: LifeLines is a large prospective population-based three generation cohort study in the north of the Netherlands. Different recruitment strategies were adopted: recruitment of an index population via general practitioners, subsequent inclusion of their family members, and online self-registration. Our aim was to investigate the representativeness of the adult study population at baseline and to evaluate differences in the study population according to recruitment strategy. METHODS: Demographic characteristics of the LifeLines study population, recruited between 2006-2013, were compared with the total adult population in the north of the Netherlands as registered in the Dutch population register. Socioeconomic characteristics, lifestyle, chronic diseases, and general health were further compared with participants of the Permanent Survey of Living Conditions within the region (2005-2011, N = 6,093). Differences according to recruitment strategy were assessed. RESULTS: Compared with the population of the north of the Netherlands, LifeLines participants were more often female, middle aged, married, living in a semi-urban place and Dutch native. Adjusted for differences in demographic composition, in LifeLines a smaller proportion had a low educational attainment (5% versus 14%) or had ever smoked (54% versus 66%). Differences in the prevalence of various chronic diseases and low general health scores were mostly smaller than 3%. The age profiles of the three recruitment groups differed due to age related inclusion criteria of the recruitment groups. Other differences according to recruitment strategy were small. CONCLUSIONS: Our results suggest that, adjusted for differences in demographic composition, the LifeLines adult study population is broadly representative for the adult population of the north of the Netherlands. The recruitment strategy had a minor effect on the level of representativeness. These findings indicate that the risk of selection bias is low and that risk estimates in LifeLines can be generalized to the general population.