On Top of Everything: a study protocol for a cluster-randomised controlled trial testing a teacher training programme to teach mindfulness among students in Danish upper secondary schools and schools of health and social care.

BACKGROUND: Mental health is decreasing among young people in Denmark. Our primary aim is to evaluate the effectiveness of a teacher training programme to teach mindfulness as part of regular classroom teaching in Danish upper secondary schools and schools of health and social care on students' self-reported mental well-being 6 months from baseline. Secondary aims are (1) to evaluate the effectiveness in a vulnerable subgroup as well as in the total population of students 3 and 6 months from baseline using other outcome measures on mental health and (2) to investigate the facilitators and barriers among teachers to implement mindfulness in schools. METHODS: This pragmatic cluster-randomised two-arm superiority trial includes 30 upper secondary schools, 13 schools of health and social care, 76 teachers, and approximately 1100 students aged 16 to 24 years. Our intervention is multi-level and consists of (a) a teacher training programme and (b) a mindfulness programme delivered to students. Students in control schools receive education as usual. Our primary study population is the total population of students. The primary outcome is changes in the short version of the Warwick-Edinburgh Mental Well-Being Scale (SWEMWBS). We also evaluate the effectiveness in a vulnerable subgroup (the 15% with the lowest SWEMWBS score), as well as in the total population of students 3 and 6 months from baseline using other outcome measures on mental health. Data will be analysed using repeated measurement models taking clusters into account. Facilitators and barriers among teachers to implement mindfulness in schools will be investigated through qualitative focus group interviews. DISCUSSION: The trial will estimate the effectiveness of a population-based strategy on mental health in Danish young people enrolled in education. TRIAL REGISTRATION: ClinicalTrials.gov NCT04610333 . Registered on October 10 2020.

SARS-CoV-2 Infection Rates Following Use of Regular Compared With Defective Respirators When Caring for COVID-19 Patients: A Retrospective Follow-up Study.

BACKGROUND: There is strong observational evidence that respirators are highly effective in protecting the users from being infected with Middle East respiratory syndrome and severe acute respiratory syndrome coronavirus (SARS-CoV), but the evidence for SARS-CoV-2 during daily work is limited. This study utilized a subset of healthcare workers' temporary use of a new brand respirator with frequent defects when caring for coronavirus disease 2019 (COVID-19) patients to assess the protective effect of regular respirators against SARS-CoV-2 infection. METHODS: We retrospectively followed 463 participants wearing a regular respirator and 168 wearing the new brand respirator day-by-day when caring for COVID-19 patients until testing polymerase chain reaction positive for SARS-CoV-2 between 27th December 2020 and 14th January 2021. RESULTS: We observed seven and eight incident SARS-CoV-2-infected cases. This corresponded with daily infection rates of 0.2 and 0.5%, an incidence rate ratio of 0.4 [95% confidence interval (CI) 0.1; 1.0], and an incidence rate difference of 0.3% (95% CI -0.1; 0.8) when comparing a regular with the new brand respirator. DISCUSSION: We regard the new brand respirator a sham intervention, and this study thus provides further evidence for the protective effect of respirators when exposed to SARS-CoV-2 virus.

Considerations for Using Multiple Imputation in Propensity Score-Weighted Analysis - A Tutorial with Applied Example.

Purpose: Propensity score-weighting for confounder control and multiple imputation to counter missing data are both widely used methods in epidemiological research. Combination of the two is not trivial and requires a number of decisions to produce valid inference. In this tutorial, we outline the assumptions underlying each of the methods, present our considerations in combining the two, discuss the methodological and practical implications of our choices and briefly point to alternatives. Throughout we apply the theory to a research project about post-traumatic stress disorder in Syrian refugees. Patients and Methods: We detail how we used logistic regression-based propensity scores to produce "standardized mortality ratio"-weights and Substantive Model Compatible-Full Conditional Specification for multiple imputation of missing data to get the estimate of association. Finally, a percentile confidence interval was produced by bootstrapping. Results: A simple propensity score model with weight truncation at 1st and 99th percentile obtained acceptable balance on all covariates and was chosen as our model. Due to computational issues in the multiple imputation, two levels of one of the substantive model covariates and two levels of one of the auxiliary covariates were collapsed. This slightly modified propensity score model was the substantive model in the SMC-FCS multiple imputation, and regression models were set up for all partially observed covariates. We set the number of imputations to 10 and number of iterations to 40. We produced 999 bootstrap estimates to compute the 95-percentile confidence interval. Conclusion: Combining propensity score-weighting and multiple imputation is not a trivial task. We present considerations necessary to do so, realizing it is demanding in terms of both workload and computational time; however, we do not consider the former a drawback: it makes some of the underlying assumptions explicit and the latter may be a nuisance that will diminish with faster computers and better implementations.

The association between long-distance migration and PTSD prevalence in Syrian refugees.

BACKGROUND: Refugees are forced migrants but there is a large variation in the distance that refugees cover and there is a paucity in the evidence of how this may affect refugees' health and health care needs. OBJECTIVE: We investigated the association between long-distance migration and post-traumatic stress disorder (PTSD), a serious psychiatric disorder associated with deteriorating mental and somatic health. METHODS: Included from 2016-2019 were adult Syrian refugees in Lebanon and Denmark that arrived up to 12 months prior to inclusion. PTSD was assessed using the Harvard Trauma Questionnaire and the estimate of association was obtained by multiply imputing missing data and adjusting for confounding by propensity score-weighting with covariates age, sex, socioeconomic status, trauma experience and general mental well-being, reporting the bootstrap 95-percentile confidence interval (95% CI). Additionally, a number of sensitivity analyses were performed. RESULTS: Included were 599 participants in Lebanon (mean age 35 years old, 73% being female) and 133 participants in Denmark (mean age 30 years old, 47% being female). After multiply imputing missing data and propensity score-weighted adjustment for confounding, migration to Denmark instead of Lebanon was associated with an increase in PTSD prevalence of 9 percentage point (95% CI [-1; 19] percentage point). CONCLUSIONS: Long-distance migration may be associated with an increase in PTSD prevalence in refugees. The migration could be an important factor to consider when assessing refugees' and asylum seekers' health. Practitioners should consider "long-distance migration" in refugee health screenings and in particular when assessing the risk of post-traumatic stress disorder. Future research should be designed to ultimately lead to studies of relevant interventions to lower the risk of post-traumatic stress disorder in refugees.

Is patient activation a mediator of the effect of a health promoting intervention in adults at high risk of type 2 diabetes? A longitudinal path model analysis within a randomised trial.

BACKGROUND: Exploring mediators of preventive intervention effects has important implications for the planning of complex interventions. Our aim was to assess the extent to which knowledge, skills and confidence to manage health, here measured as "patient activation", was a mediator of the effect of the intervention "Live your life without diabetes" on weight, waist circumference and systolic blood pressure at 12 months follow-up in adults at high risk of type 2 diabetes. METHODS: Autoregressive path models with three time points of measurement, and contemporaneous and constant b paths were used in a randomised controlled trial (RCT). The RCT took place in a Danish municipal healthcare center and included 127 individuals aged 28 to 70 years with fasting plasma glucose: 6.1-6.9 mmol/l and/or glycated haemoglobin (HbA1c): 42.0-47.9 mmol/mol. Participants were randomised to routine care (n = 64), or intervention (n = 63). The intervention group received an empirical and theory-based intervention delivered over four two-h group sessions during five weeks, and two further sessions after one and six months. The outcomes were weight, waist circumference and systolic blood pressure, and the mediator was patient activation, measured by the self-reported Patient Activation Measure (PAM). Data for the present study was derived from questionnaires and clinical measures from baseline, three- and 12-months follow-up. RESULTS: Mediated effects via PAM on: weight: - 0.09 kg (95% CI - 0.38 to 0.20) out of the total effect - 1.09 kg (95% CI - 3.05 to 0.87); waist circumference: - 0.04 cm (95% CI - 0.36 to 0.28) out of the total effect - 1.86 cm (95% CI - 4.10 to 0.39); and systolic blood pressure: - 0.31 mmHg (- 1.10 to 0.49) out of the total effect - 2.73 mmHg (95% CI - 6.34 to 0.87). CONCLUSION: We found no mediating effects of patient activation as a single variable of the intervention "Live your life without diabetes" on weight, waist circumference and systolic blood pressure at 12 months follow-up in adults at high risk of type 2 diabetes. Our study demonstrates an analytic approach for estimating mediating effects in complex interventions that comply with the criteria on temporal ordered data. Future studies should include possible interacting variables.

The effectiveness of mindfulness-based stress reduction for school teachers: a cluster-randomized controlled trial.

BACKGROUND: Teaching has been found to be one of the most stressful occupations. Hence, current interest in reducing stress and enhancing the well-being of teachers is strong. Mindfulness-based stress reduction (MBSR) is documented to be effective in reducing stress and increasing well-being. This study investigated the effectiveness of delivering MBSR to lower secondary school teachers as a part of a teacher-training programme. METHODS: This study was a nested trial within the parallel cluster-randomized controlled trial, Stress-free Everyday LiFe for Children and Adolescents REsearch (SELFCARE). Schools were recruited from all five geographical regions in Denmark between May 2018 and May 2019. One to three teachers from each school were allowed to participate. At baseline, 110 schools, representing 191 lower secondary school teachers, were cluster-randomized to intervention or a wait-list control group. The intervention group received MBSR during 2019 and the wait-list control group during 2020. Data were collected at baseline and after 3 and 6 months. The primary outcome was measured by Cohen's Perceived Stress Scale (PSS). Data were analyzed using a mixed-effect linear regression model and bootstrapped for cluster effects. RESULTS: At 3 months, the intervention group statistically significantly reduced their PSS score 1.7 [95% confidence interval (CI) 0.04-3.3] points more than did the wait-list control group. At 6 months, the intervention group had statistically significantly reduced their mean PSS score 2.1 (95% CI: 0.5-3.8) points more than the wait-list control group. CONCLUSION: It is possible to reduce perceived stress among lower secondary school teachers by delivering MBSR as part of a teacher-training programme.

Mediators for the Effect of Compassion Cultivating Training: A Longitudinal Path Analysis in a Randomized Controlled Trial Among Caregivers of People With Mental Illness.

Background: There is a paucity of research on mediators of change, within compassion training programs. The aim was to investigate the mediators, of an 8-week compassion cultivation training (CCT) program, on the effect of psychological distress on caregivers of people with a mental illness. Method: Longitudinal path models in a randomized controlled trial (RCT). One hundred ninety-two participants were assessed for eligibility, and 161 participants were included into the trial and randomized. The main outcome was psychological distress measured by the Depression, Anxiety and Stress scale at 6 months. Mediators included self-compassion (SC), mindfulness (FM), emotion regulation (ER), emotion suppression (ES), and cognitive reappraisal (CR). Baseline, post, and 3- and 6-month follow-up measurements were collected. Results: The mediated effects for CCT are as follows: depression at 6 months: SC: -1.81 (95% CI: -3.31 to -0.31); FM: -1.98 (95% CI: -3.65 to -0.33); ER: -0.14 (95% CI: -1.31 to 1.02); anxiety at 6 months: SC: -0.71 (95% CI: -1.82 to 0.40); FM: -1.24 (95% CI: -2.39 to -0.09); ER: 0.18 (95% CI: -1.04 to 1.40); stress at 6 months: SC: -1.44 (95% CI: -2.84 to -0.05); FM: -2.17 (95% CI: -3.63 to -0.71); ER: -0.27 (95% CI: -1.51 to 0.98). Conclusion: Mindfulness and self-compassion are important components in reducing psychological distress experienced by informal caregivers of people with a mental illness. Results contribute to the knowledge about the underlying mechanisms of CCT.

Linoleic acid in adipose tissue and the risk of myocardial infarction: a case-cohort study.

PURPOSE: We investigated risk of myocardial infarction (MI) associated with the content of linoleic acid (LA) in adipose tissue, a biomarker of long-term dietary intake of LA and a marker of endogenous LA exposure. METHODS: Between 1993 and 1997, 57,053 middle-aged subjects were included in the Danish Diet, Cancer and Health cohort. We performed a case-cohort study that included a random sample of the full cohort (n = 3167) and all incident MI cases appearing during 16 years of follow-up (n = 2819). Information on incident MI cases was obtained by linkage with Danish nationwide registries. Adipose tissue biopsies were taken from the buttocks of the participants, and their fatty acid composition was determined using gas chromatography. HRs (hazard ratios) with 95% confidence intervals (CIs) were used to describe the associations between content of LA in adipose tissue and the risk of MI. HRs were calculated using weighted Cox proportional hazards regression with robust variance. RESULTS: After adjustment for established risk factors of MI, adipose tissue content of LA was not associated with the risk of MI in men and women combined (quintiles 5 versus 1, HR, 1.03 (95% CI, 0.85-1.25), P-trend = 0.970) or in men and women separately (quintiles 5 versus 1, HR, 1.05 (95% CI, 0.83-1.33), P-trend = 0.871 and quintiles 5 versus 1, HR, 0.99 (95% CI 0.72-1.37), P-trend = 0.928, respectively). Investigating the association between LA and MI with a shorter, 5- or 10-year duration of follow-up provided similar results. CONCLUSION: Content of LA in adipose tissue was not associated with the risk of MI.

Stress-free Everyday LiFe for Children and Adolescents REsearch (SELFCARE): a protocol for a cluster randomised trial testing a school teacher training programme to teach mindfulness (".b").

BACKGROUND: There is a call for sustainable, evidence-based interventions in schools to promote mental health in schoolchildren. Our primary aim of this trial is to evaluate the effectiveness in vulnerable pupils of a school teacher training programme to teach mindfulness (".b" programme) as a part of compulsory class room teaching in Danish schools on the pupils' self-reported mental health at 6-month follow-up. Our secondary aim is to evaluate the effectiveness of the school teacher training programme to teach the ".b"-programme as a part of compulsory class room teaching among the total pupil population on the pupils' self-reported mental health at 3 and 6 months after baseline. METHODS: The pragmatic cluster two-armed randomised controlled trial includes 110 municipal or private schools from all five regions in Denmark; 191 school teachers and approximately 2000 pupils at 11-15 years of age. Exclusion criteria; for schools: < 100 pupils; for pupils: parental opt out. Our intervention consists of (A) a school teacher training programme and (B) the ".b"-programme delivered as part of compulsory class room teaching in schools to pupils at the age of 11-15 years. The pupils in the control schools receive education as usual. Our primary study population is the vulnerable subgroup with a Strengths and Difficulties Questionnaire (SDQ) total difficulties score > 80% percentile at baseline (approximately 400 pupils). The primary outcome is change in the SDQ total score by the pupils. We also evaluate the effectiveness among the total pupil study population and in girls and boys, respectively and use other measures on mental health. Data will be analysed with repeated measurement models taken clusters into account. DISCUSSION: This large-scale trial will estimate the effectiveness of a population-based strategy on mental health in Danish schoolchildren. The trial evaluates the effect of a school teacher training programme, where teachers are trained in teaching the ".b" programme. The ".b" programme will be taught as a part of compulsory class room teaching. The intervention takes implementation issues into account. Effectiveness will be evaluated both in a vulnerable subgroup and among the total population. Trial registration number ClinicalTrials.gov Identifier: NCT04208113, registered December 23 2019, https://clinicaltrials.gov/ct2/show/NCT04208113 .

Does parental farm upbringing influence the risk of asthma in offspring? A three-generation study.

BACKGROUND: A farm upbringing has been associated with lower risk of asthma and methylation of asthma-related genes. As such, a farm upbringing has the potential to transfer asthma risk across generations, but this has never been investigated. We aimed to study the generational effects from a parental farm upbringing on offspring asthma. METHODS: Our study involved three generations: 5759 participants from the European Community Respiratory Health Survey (ECRHS) study (born 1945-1971, denoted G1), their 9991 parents (G0) and their 8260 offspring (G2) participating in RHINESSA (Respiratory Health In Northern Europe, Spain and Australia). Questionnaire data were collected on G0 and G1 from G1 in 2010 and on G2 from themselves in 2013. The parental/grandparental place of upbringing was categorized: (i) both parents from farm; (ii) mother from farm, father from village/city; (iii) father from farm, mother from village/city; (iv) both parents from village or one parent from village and one from city; (v) both parents from city (reference group). Grandparental upbringing was equivalently categorized. Offspring asthma was self-reported and data were analysed using Cox-regression models with G2 age as the time scale. RESULTS: A parental farm upbringing was not associated with offspring asthma when compared with city upbringing [hazard ratio (HR) 1.12, 95% confidence interval (CI) 0.74-1.69]. Findings remained similar when stratified by offspring upbringing and asthma phenotypes. Quantitative bias analyses showed similar estimates for alternative data sources. A grandparental farm upbringing was not associated with offspring asthma in either the maternal (HR 1.05, 95% CI 0.67-1.65) or paternal line (HR 1.02, 95% CI 0.62-1.68). CONCLUSIONS: This multigenerational analysis suggests no evidence of an association between parental/grandparental farm upbringing and offspring asthma.

The long-term course of fatigue following breast cancer diagnosis.

PURPOSE: Fatigue following breast cancer is a well-known problem, with both high and persistent prevalence. Previous studies suffer from lack of repeated measurements, late recruitment and short periods of follow-up. The course of fatigue from diagnosis and treatment to the long-time outcome status is unknown as well as differences in the level of fatigue between treatment regimens. The purpose of this study was to describe the long-time course of fatigue from the time of clinical suspicion of breast cancer, its dependence of patient characteristics and treatment regimens and the comparison with the course of fatigue among women with the same suspicion, but not diagnosed with breast cancer. METHODS: Three hundred thirty-two women referred to acute or subacute mammography was followed with questionnaires from before the mammography and up to 1500 days. Fatigue was measured by the Multidimensional Fatigue Inventory (MFI-20). The women reported their initial level of fatigue before the mammography and thus without knowledge of whether they had cancer or not. Both women with and without cancer were followed. Women with cancer were identified in the clinical database established by Danish Breast Cancer Cooperative Group (DBCG) to collect information on treatment regimen. RESULTS: Compared to fatigue scores before diagnosis, women with breast cancer reported a large increase of fatigue, especially in the first 6 months, followed by a slow decrease over time. Despite the long follow-up period, the women with breast cancer did not return to their level of fatigue at time of the mammography. Women without breast cancer, experienced a rapid decrease of fatigue after disproval of diagnosis followed by a steadier period. CONCLUSIONS: Fatigue is a persistent problem in women diagnosed with breast cancer, even several years following diagnosis and treatment. The women with breast cancer were most affected by fatigue in the first 6 months after diagnosis.

Asylum seekers' and Refugees' Changing Health (ARCH) study protocol: an observational study in Lebanon and Denmark to assess health implications of long-distance migration on communicable and non-communicable diseases and mental health.

INTRODUCTION: By end of 2018, the European Union countries hosted approximately 2.5 million refugees and Lebanon alone hosted more than 1 million. The majority of refugees worldwide came from Syria. The prevailing study design in published studies on asylum seekers' and refugees' health leaves a number of fundamental research questions unanswerable. In the Asylum seekers' and Refugees' Changing Health (ARCH) study, we examine the health of a homogeneous group of refugees and asylum seekers in two very different host countries with very different migration histories. We aim to study the health impact of the migration process, living conditions, access to healthcare, gene-environment interactions and the health transition. METHODS AND ANALYSIS: ARCH is an international multisite study of the health of adult (>18 years old) Syrian refugees and asylum seekers in Lebanon and Denmark. Using a standardised framework, we collect information on mental and physical health using validated scales and biological samples. We aim to include 220 participants in Danish asylum centres and 1100 participants in Lebanese refugee camps and settlements. We will use propensity score weights to control for confounding and multiple imputation to handle missing data. ETHICS AND DISSEMINATION: Ethical approval has been obtained in Lebanon and Denmark. In the short term, we will present the cross-sectional association between long-distance migration and the results of the throat and wound swab, blood and faeces samples and mental health screenings. In the longer term, we are planning to follow the refugees in Denmark with collection of dried blood spots, mental health screenings and semistructured qualitative interviews on the participant's health and access to healthcare in the time lived in Denmark. Here, we present an overview of the background for the ARCH study as well as a thorough description of the methodology.

Asthma and selective migration from farming environments in a three-generation cohort study.

Individuals raised on a farm appear to have less asthma than individual raised elsewhere. However, selective migration might contribute to this as may also the suggested protection from farm environment. This study investigated if parents with asthma are less likely to raise their children on a farm. This study involved three generations: 6045 participants in ECRHS/RHINE cohorts (born 1945-1973, denoted G1), their 10,121 parents (denoted G0) and their 8260 offspring participating in RHINESSA (born 1963-1998, denoted G2). G2-offspring provided information on parents not participating in ECRHS/RHINE. Asthma status and place of upbringing for all three generations were reported in questionnaires by G1 in 2010-2012 and by G2 in 2013-2016. Binary regressions with farm upbringing as outcome were performed to explore associations between parental asthma and offspring farm upbringing in G0-G1 and G1-G2. Having at least one parent with asthma was not associated with offspring farm upbringing, either in G1-G2 (RR 1.11, 95% CI 0.81-1.52) or in G0-G1 (RR 0.99, 0.85-1.15). G1 parents with asthma born in a city tended to move and raise their G2 offspring on a farm (RR 2.00, 1.12-3.55), while G1 parents with asthma born on a farm were less likely to raise their G2 offspring on a farm (RR 0.34, 0.11-1.06). This pattern was not observed in analyses of G0-G1. This study suggests that the protective effect from farm upbringing on subsequent asthma development could not be explained by selective migration. Intriguingly, asthmatic parents appeared to change environment when having children.

Parent Training for Preschool ADHD in Routine, Specialist Care: A Randomized Controlled Trial.

OBJECTIVE: Parent training is recommended for attention-deficit/hyperactivity disorder (ADHD) in preschool children. Evidence-based interventions are important, but only if they produce better outcomes than usual care. METHOD: The authors conducted a multicenter, 2-arm, parallel-group, randomized controlled trial in routine specialist ADHD clinics in the Danish Child and Adolescent Mental Health Services. Children (N = 164, 3-7 years old) with ADHD received a well-established parent training program (New Forest Parenting Programme; n = 88) or treatment as usual (n = 76). The primary outcome was parent ratings of child ADHD symptoms. Secondary outcomes included teacher ratings and direct observations of ADHD symptoms. Outcomes were measured at baseline, after treatment, and at follow-up (36 weeks later). Representativeness of participants was evaluated against the total national cohort of children (N = 1,378, 3-7 years old) diagnosed with ADHD during the same period using the Danish Civil Registration System. Statistical analysis used a repeated measure model. RESULTS: After treatment, the parent training program was superior to treatment as usual on parent-rated ADHD symptoms (p = .009; effect size d = 0.30) and on parenting self-efficacy and family strain. Effects persisted to 36 weeks after treatment. There were no effects on teacher ratings or direct observations of ADHD or on ratings of conduct problems or parenting. The clinical sample was similar to the national cohort of young children with ADHD. CONCLUSION: Evidence-based parent training has value as an intervention for preschool ADHD in routine clinical settings. As in previous trials, effects were restricted to parent-reported outcomes. Surprisingly, there were no effects on child conduct problems. CLINICAL TRIAL REGISTRATION INFORMATION: A Controlled Study of Parent Training in the Treatment of ADHD in Young Children (D'SNAPP). http://clinicaltrial.gov/;NCT01684644.

Short-term effects of night shift work on breast cancer risk: a cohort study of payroll data.

Objectives The objective was to examine if night shift work is a short-term risk factor for breast cancer, including combined estrogen receptor (ER) and human epidermal growth factor 2 (HER2) breast cancer subtypes. Methods The cohort comprised 155 540 public sector female workers in Denmark who were followed from 2007-2012. Day-to-day work-hour information was available from payroll registers and 1245 incident cases of breast cancer were identified in national cancer registries together with receptor subtype information. Results A rate ratio (RR) of 0.90 [95% confidence interval (95% CI) 0.80-1.01] was observed for workers ever working night shifts during the follow-up period compared with workers only working day shifts after adjustment for age, age at first child, parity, family history of breast or ovarian cancer, sex hormones, medications related to alcoholism, family educational level, mammography screening, and other potential confounders. Comparable results were seen for the inception population of employees with first recorded employment after 2007. Modestly increased RR were suggested for breast cancer subtypes characterized by a positive HER2 status irrespective of ER status. Conclusions These findings do not support an overall short-term effect of night shift work on breast cancer risk. Future studies should explore further the impact of HER2 status.

Response to Dr Stevens' letter ref. Visitisen et al: "Short-term effects of night shift work on breast cancer risk: a cohort study of payroll data".

We thank Dr Richard Stevens for his comments (1) on our recent article that showed no increased risk of breast cancer following recent night shift work when compared with recent day shift work (2). This finding was based on linkage of day-by-day information on working hours and breast cancer incidence data. Results are thus less likely to have been biased by differential misclassification than findings from earlier studies relying on self-report (3). We defined a night shift as ≥3 hours of work between 24:00-05:00 hours and a day shift as ≥3 hours work between 6:00-20:00 hours. This day shift definition did not exclude shifts starting before 05:00 or ending after 24:00 hours. However, this affected only 0.02% and 0.3% of all day shifts, respectively. This diminutive misclassification, that is expected to be non-differential, can hardly explain our negative findings. It is suggested that shifts that begin after 07:00 and end before 18:00 would constitute a more sensible baseline comparison group. Since the biological mechanism is not certain, it is not obvious to us if this will be a more appropriate reference than the present. However, we agree that future studies should test how different definitions of shifts affect the risk of breast cancer, which will be possible using this type of data. We only had information on working hours from 2007 and onwards, and night shift work prior to 2007 could have confounded our analyses towards no effect but only if inversely associated with night shift work in 2007 or later. We find this unlikely. Left truncation could also have biased findings towards the null. We therefore supplemented analyses of the total study population with analyses of the one-third of the population with first recorded employment in 2008 or later (the inception population). Even if the mean age was 35.5 years - and many undoubtedly had been working (with and without night shifts) prior to 2008 - this population should be less affected by such selection bias, but we observed similar risk estimates as for the total study population. Taken together, we find that our study provides rather robust evidence of no short-term breast cancer risk following recent night shift work. It must, however, be stressed that data did not allow assessment of a possible long-term risk. Reference 1. Stevens R. Letter ref. Vitisen et al: "Short-term effects of night shift work on breast cancer risk: a cohort study of payroll data". Scand J Work Environ Health. 2017;43(1):95. http://dx.doi.org/10.5271/sjweh.3607 2. Vistisen HT, Garde AH, Frydenberg M, Christiansen P, Hansen AM, Hansen J, Bonde JP, Kolstad HA. Short-term effects of night shift work on breast cancer risk: A cohort study of payroll data. Scand J Work Environ Health. 2017;43(1):59-67. http://dx.doi.org/10.5271/sjweh.3603. 3. Ijaz S, Verbeek J, Seidler A, Lindbohm ML, Ojajarvi A, Orsini N, Costa G, Neuvonen K. Night-shift work and breast cancer--a systematic review and meta-analysis. Scand J Work Environ Health. 2013 Sep 1;39(5):431-47. http://dx.doi.org/10.5271/sjweh.3371.

Risk of hypersensitivity pneumonitis and interstitial lung diseases among pigeon breeders.

We studied the risk of hypersensitivity pneumonitis and other interstitial lung diseases (ILDs) among pigeon breeders.This is a retrospective follow-up study from 1980 to 2013 of 6920 pigeon breeders identified in the records of the Danish Racing Pigeon Association. They were compared with 276 800 individually matched referents randomly drawn from the Danish population. Hospital based diagnoses of hypersensitivity pneumonitis and other ILDs were identified in the National Patient Registry 1977-2013. Stratified Cox regression analyses estimated the hazard ratios (HR) of hypersensitivity pneumonitis and other ILDs adjusted for occupation, residence and redeemed prescription of medication with ILDs as a possible side-effect. Subjects were censored at death, emigration or a diagnosis of connective tissue disease.The overall incidence rate of ILD was 77.4 per 100 000 person-years among the pigeon breeders and 50.0 among the referents. This difference corresponded to an adjusted HR of 1.56 (95% CI 1.26-1.94). The adjusted HRs of hypersensitivity pneumonitis and other ILDs for pigeon breeders were 14.36 (95% CI 8.10-25.44) and 1.33 (95% CI 1.05-1.69), respectively.This study shows an increased risk of ILD among pigeon breeders compared with the referent population. Protective measures are recommended even though ILD leading to hospital contact remains rare among pigeon breeders.

The Effectiveness of Parent Training as a Treatment for Preschool Attention-Deficit/Hyperactivity Disorder: Study Protocol for a Randomized Controlled, Multicenter Trial of the New Forest Parenting Program in Everyday Clinical Practice.

BACKGROUND: Parent training is recommended as the first-line treatment for attention-deficit/hyperactivity disorder (ADHD) in preschool children. The New Forest Parenting Programme (NFPP) is an evidence-based parenting program developed specifically to target preschool ADHD. OBJECTIVE: The objective of this trial is to investigate whether the NFPP can be effectively delivered for children referred through official community pathways in everyday clinical practice. METHODS: A multicenter randomized controlled parallel arm trial design is employed. There are two treatment arms, NFPP and treatment as usual. NFPP consists of eight individually delivered parenting sessions, where the child attends during three of the sessions. Outcomes are examined at three time points (T1, T2, T3): T1 (baseline), T2 (week 12, post intervention), and T3 (6 month follow/up). 140 children between the ages of 3-7, with a clinical diagnosis of ADHD, informed by the Development and Well Being Assessment, and recruited from three child and adolescent psychiatry departments in Denmark will take part. Randomization is on a 1:1 basis, stratified for age and gender. RESULTS: The primary endpoint is change in ADHD symptoms as measured by the Preschool ADHD-Rating Scale (ADHD-RS) by T2. Secondary outcome measures include: effects on this measure at T3 and T2 and T3 measures of teacher reported Preschool ADHD-RS scores, parent and teacher rated scores on the Strength & Difficulties Questionnaire, direct observation of ADHD behaviors during Child's Solo Play, observation of parent-child interaction, parent sense of competence, and family stress. Results will be reported using the standards set out in the Consolidated Standards of Reporting Trials Statement for Randomized Controlled Trials of nonpharmacological treatments. CONCLUSIONS: The trial will provide evidence as to whether NFPP is a more effective treatment for preschool ADHD than the treatment usually offered in everyday clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov NCT01684644; https://clinicaltrials.gov/ct2/show/NCT01684644?term= NCT01684644&rank=1 (Archived by WebCite at http://www.webcitation/6eOOAe8Qe).

Symptoms of Posttraumatic Stress after Intensive Care Delirium.

INTRODUCTION: Long-term psychological consequences of critical illness are receiving more attention in recent years. The aim of our study was to assess the correlation of ICU-delirium and symptoms of posttraumatic stress disorder (PTSD) anxiety and depression after ICU-discharge in a Danish cohort. METHODS: A prospective observational cohort study assessing the incidence of delirium in the ICU. Psychometrics were screened by validated tools in structured telephone interviews after 2 months (n = 297) and 6 months (n = 248) after ICU-discharge. RESULTS: Delirium was detected in 54% of patients in the ICU and symptoms of PTSD in 8% (2 months) and 6% (6 months) after ICU-discharge. Recall of ICU stay was present in 93%. Associations between ICU-delirium and post-discharge PTSD-symptoms were weak and insignificant. Memories of delusions were significantly associated with anxiety after two months. Remaining associations between types of ICU-memories and prevalence of post-discharge symptoms of PTSD, anxiety, and depression were insignificant after adjusting for age. Incidence of ICU-delirium was unaffected by preadmission use of psychotropic drugs. Prevalence of PTSD-symptoms was unaffected by use of antipsychotics and sedation in the ICU. CONCLUSION: ICU-delirium did not increase the risk of PTSD-symptoms at 2 and 6 months after ICU discharge.