Developing a digital informed consent app: opportunities and challenges of a new format to inform and obtain consent in public health research.

BACKGROUND: Informed consent procedures for large population-based cohort studies should be comprehensive and easy-to-use. This is particularly challenging when participants from different socio-economic groups and multicultural ethnic backgrounds are involved. Recently, more and more studies have tried to use multimedia in informed consent procedures. We describe the development and testing of a digital informed consent app and elaborate on whether this may contribute to a comprehensive and practical procedure to obtain informed consent for public health research. METHODS: In a sample of parents with young children, we used a mixed method approach to study the user experience of an informed consent app and evaluate whether it can be used to adequately inform people and register their consent. Through semi-structured interviews we investigated participants' experiences with and opinions about the app, with a special focus on comprehensibility of the content and the usability of the app. Information retention questions were asked to evaluate to what extent participants could recall key aspects of the provided study information. RESULTS: The 30 participants in this study used the app between 4 and 15 min to give their consent. Overall, they found the app well-designed, informative and easy to use. To learn more about the study for which informed consent is asked, most of the participants chose to watch the animated film, which was generally found to convey information in a clear manner. The identification process was met with mixed reactions, with some feeling it as a secure way to give consent, while for others it contradicted their view of using data anonymously. Information retention questions showed that while all participants remembered various aspects of the study, fewer than half answered all four questions satisfactorily. CONCLUSION: Our study shows that a well-designed informed consent app can be an effective tool to inform eligible participants and to record consents. Still, some issues remain, including trust barriers towards the identification procedure and lack of information retention in some participants. When implementing consent procedures that incorporate digital formats, it may be beneficial to also invest in a complementary face-to-face recruitment approach.

Measuring sleep health in primary school-aged children: A systematic review of instruments and their content validity.

STUDY OBJECTIVES: This review aimed to summarize instruments that measure one or more domains of sleep health (i.e. duration, quality, efficiency, timing, daytime sleepiness and sleep-related behaviors) in a general population of 4-12-year old children, and to assess these instruments' content validity. Other measurement properties were evaluated for instruments with indications of sufficient content validity. METHODS: A systematic literature search was performed in PubMed, PsycINFO, Web of Science, and EmBase. Methodological quality, content validity, and other measurement properties were assessed via the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology. Instruments with indications of sufficient content validity (i.e. relevance, comprehensiveness and comprehensibility) were further evaluated on other measurement properties (i.e. other aspects of validity, reliability, responsiveness). A modified GRADE approach was applied to determine the quality of evidence. RESULTS: Twenty instruments, containing 36 subscales, were included. None of the instruments measured all sleep health domains. For five (subscales of) instruments sufficient relevance and comprehensibility was found. The quality of evidence ranged from very low to moderate. For these five instruments all additional measurement properties were assessed. Sufficient results were found for structural validity (n = 1), internal consistency (n = 1), and construct validity (n = 1), with quality of evidence ranging from very low to high. CONCLUSIONS: Several (subscales of) instruments measuring domains of child sleep health showed good promise, demonstrating sufficient relevance, comprehensibility, and some also sufficient results on other measurement properties. However, more high quality studies on instrument development and the evaluation of measurement properties are required.PROSPERO registration number: CRD42021224109.

The Unique Extended Selection Cohorts Design for the Evaluation of the School-Based Jump-In Intervention on Dietary Habits: A Study Protocol.

Background: To promote healthy dietary and physical activity behaviour among primary school children, the city of Amsterdam structurally implements the school-based Jump-in intervention in over half of its primary schools. Previously shown to be effective in stimulating physical activity and outside recess play, our study is the first to evaluate Jump-in's effect on children's dietary behaviour. Evaluating the effectiveness and implementation process of an intervention in a real-life setting requests an alternative study design. Methods: we chose a mixed-methods, quasi-experimental Extended Selection Cohorts design to evaluate Jump-in's effectiveness and implementation process. Children and parents from the first ten primary schools that enrolled in the programme in 2016-2017 were invited to participate. The primary outcomes were children's dietary behaviour and behavioural determinants, assessed by child and parent questionnaires, and photographs of the food and drinks children brought to school. Process indicators, contextual factors and satisfaction with the programme were assessed by interviews with health promotion professionals, school principals, school project coordinators, and teachers; focus group discussions with parents and children; and document analysis. Discussion: Conducting research in a real-life setting is accompanied by methodological challenges. Using an Extended Selection Cohorts design provides a valuable alternative when a Randomized Controlled design is not feasible.

The role of body weight, fat distribution and weight change in ethnic differences in the 9-year incidence of hypertension.

OBJECTIVE: To investigate the role of body composition (body weight, fat distribution and weight change over time) in ethnic differences in the incidence of hypertension in an ethnic Dutch, South Asian Surinamese and African Surinamese background population living in the Netherlands. METHODS: We included 361 participants without hypertension at baseline (147 ethnic Dutch, 82 South Asian Surinamese, 132 African Surinamese), aged 35-60 years, in whom anthropometric measurements and blood pressures were measured at baseline and after mean 9 years of follow-up. Data were analysed using logistic regression analyses, with hypertension at follow up as a dependent variable. RESULTS: Body weight, fat distribution and weight gain were positively associated with the risk of developing hypertension; these associations did not statistically significantly differ between ethnic groups [odds ratios (ORs), 95% confidence interval (95% CI) per SD: BMI 1.5 (1.2-2.0); waist circumference 1.5 (1.2-1.9); waist to hip ratio (WHR) 1.4 (1.1-1.9), weight gain of 1-2.9 kg/m 1.8 (0.9-3.8)]. As compared with Dutch, a higher incidence of hypertension was found among South Asian Surinamese [OR 2.6 (1.4-4.8)] and in particular among African Surinamese [OR 3.1 (1.76-5.30)]. Among South Asian Surinamese, adjustment for WHR attenuated the OR the most [OR 1.9 (1.0-3.7)]; among African Surinamese, the strongest effect was observed for adjustment by BMI and WHR simultaneously [OR 2.5 (1.4-4.4)]. CONCLUSION: The ethnic differences in the incidence of hypertension among a middle-aged group with a Dutch, South Asian Surinamese and African Surinamese background were partly explained by body composition. This suggests that other factors may be involved, including genetic factors or unidentified other determinants.

Overweight and obesity in young Turkish, Moroccan and Surinamese migrants of the second generation in the Netherlands.

OBJECTIVE: To examine differences in overweight and obesity of second-generation Turkish, Moroccan and Surinamese migrants v. first-generation migrants and the ethnic Dutch. We also studied the influence of sociodemographic factors on this association. DESIGN: Data were collected in 2008 in a cross-sectional postal and online health survey. SETTING: Four major Dutch cities. SUBJECTS: In the survey 42 686 residents aged 16 years and over participated. Data from Dutch (n 3615) and second/first-generation Surinamese (n 230/139), Turkish (n 203/241) and Moroccan (n 172/187) participants aged 16-34 years were analysed using logistic regression with overweight (BMI ≥ 25·0 kg/m²) and obesity (BMI ≥ 30·0 kg/m²) as dependent variables. BMI was calculated from self-reported body height and weight. Sociodemographic variables included sex, age, marital status, educational level, employment status and financial situation. RESULTS: After controlling for age, overweight (including obesity) was more prevalent in most second-generation migrant subgroups compared with the Dutch population, except for Moroccan men. Obesity rates among second-generation migrant men were similar to those among the Dutch. Second-generation migrant women were more often obese than Dutch women. Ethnic differences were partly explained by the lower educational level of second-generation migrants. Differences in overweight between second- and first-generation migrants were only found among Moroccan and Surinamese men. CONCLUSIONS: We did not find a converging trend for the overweight and obesity prevalence from second-generation migrants towards the Dutch host population. Therefore, preventive interventions should also focus on second-generation migrants to stop the obesity epidemic.

Ethnic differences in the association between cardiovascular risk factors and psychological distress in a population study in the Netherlands.

BACKGROUND: There is growing body of evidence of an association between cardiovascular risk factors and depressive and anxiety symptoms. The purpose of this study was to investigate whether these associations are similar in ethnic minority groups. METHODS: A random urban population sample, aged 18+, stratified by ethnicity (484 native Dutch subjects, 383 Turkish-Dutch subjects, and 316 Moroccan-Dutch subjects), in Amsterdam, the Netherlands, was interviewed with the Kessler Psychological Distress scale (K10) in combination with measurements of several cardiovascular risk factors. The association of psychological distress (defined as a K10 score above cut-off of 20) with cardiovascular risk factors (obesity, abdominal obesity, hypertension, hypercholesterolemia, low HDL cholesterol levels or diabetes), ethnicity and their interaction was analyzed using logistic regression analyses, stratified by gender and adjusted for age. RESULTS: Cardiovascular risk factors were not significantly associated with psychological distress in any of the gender/ethnic groups, with the exception of a positive association of obesity and hypertension with psychological distress in native Dutch women and a negative association of hypertension and psychological distress in Turkish men. Interaction terms of cardiovascular risk factors and ethnicity were approaching significance only in the association of obesity with the K10 in women. CONCLUSION: In this cross-sectional multi-ethnic adult population sample the majority of the investigated cardiovascular risk factors were not associated with psychological distress. The association of obesity with psychological distress varies by gender and ethnicity. Our findings indicate that the prevention of obesity and psychological distress calls for an integrated approach in native Dutch women, but not necessarily in Turkish-Dutch and Moroccan-Dutch women, in whom these problems may be targeted separately.

Ethnic differences in systemic inflammation: an investigation of C-reactive protein levels among Moroccan, Turkish and Dutch groups in the Netherlands.

OBJECTIVE: C-reactive protein (CRP) is a sensitive, non-specific systemic marker for inflammation and tissue damage in the human body and independently associated with incident cardiovascular disease (CVD) and traditional CVD risk factors. The aim of this study is to describe and analyse ethnic differences in CRP levels between Turkish, Moroccan and ethnic Dutch groups. METHODS: Data were collected in the setting of a general health survey, in Amsterdam, the Netherlands, in 2004. From 1219 adults information on physical and psychological health, lifestyle and demographic background was obtained via health interviews. In a physical examination, measurements of anthropometry and blood pressure were performed. Blood samples were collected and high-sensitive CRP was determined. RESULTS: Mean CRP levels, excluding acute inflammation, were higher among Turkish migrants (men: 2.1mg/l; women: 2.9mg/l) and Moroccan women (2.9mg/l) compared to the Dutch (men: 1.7mg/l; women: 2.3mg/l). 'High CVD risk' CRP levels (3mg/l≥CRP≥10mg/l) were also more prevalent in these groups. Ethnic differences in mean CRP levels persisted after controlling for sex, age, BMI and smoking. Ethnic differences in 'high CVD risk' CRP levels were attenuated by controlling for traditional CVD risk factors in men, but not in women. CONCLUSION: Their relatively high CRP levels put Turkish and female Moroccan migrants at higher risk of future cardiovascular events, especially women. Known determinants cannot explain ethnic differences in mean CRP levels. Traditional CVD determinants account for ethnic differences in 'high CVD risk' CRP levels among men, but not women.

Ethnic variation in validity of the estimated obesity prevalence using self-reported weight and height measurements.

BACKGROUND: We examined ethnic differences between levels of body mass index (BMI) based on self-reported and measured body height and weight and the validity of self-reports used to estimate the prevalence of obesity (BMI≥30 kg/m2) in Turkish, Moroccan, and Dutch people in the Netherlands. Furthermore, we investigated whether BMI levels and the prevalence of obesity in Turkish and Moroccan people with incomplete self-reports (missing height or weight) differ from those with complete self-reports. METHODS: Data on self-reported and measured height and weight were collected in a population-based survey among 441 Dutch, 414 Turks and 344 Moroccans aged 18 to 69 years in Amsterdam, the Netherlands in 2004. BMI and obesity were calculated from self-reported and measured height and weight. RESULTS: The difference between measured and estimated BMI was larger in Turkish and Moroccan women than in Dutch women, which was explained by the higher BMI of the Turkish and Moroccan women. In men we found no ethnic differences between measured and estimated BMI. Sensitivity to detect obesity was low and specificity was high. In participants with available self-reported and measured height and weight, self-reports produced a similar underestimation of the obesity prevalence in all ethnic groups. However, many obese Turkish and Moroccan women had incomplete self-reports, missing height or weight, resulting in an additional underestimation of the prevalence of obesity. Among men (all ethnicities) and Dutch women, the availability of height or weight by self-report did not differ between obese and non obese participants. CONCLUSIONS: BMI based on self-reports is underestimated more by Turkish and Moroccan women than Dutch women, which is explained by the higher BMI of Turkish and Moroccan women. Further, in women, ethnic differences in the estimation of obesity prevalence based on self-reports do exist and are due to incomplete self-reports in obese Turkish and Moroccan women. In men, ethnicity is not associated with discrepancies between levels of BMI and obesity prevalence based on measurements and self-reports. Hence, our results indicate that using measurements to accurately determine levels of BMI and obesity prevalence in public health research seems even more important in Turkish and Moroccan migrant women than in other populations.

Obesity and body fat distribution: ethnic differences and the role of socio-economic status.

OBJECTIVE: This study investigates differences in overweight and body fat distribution between Turkish and Moroccan migrants and the ethnic Dutch population, and the contribution of socio-economic status to their higher obesity prevalence. METHODS: Data were collected as part of a general health survey, in Amsterdam, the Netherlands (2004). From 1,285 adults information on physical and psychological health, lifestyle and demographic background was obtained through health interviews. In a physical examination body height and weight as well as waist and hip circumference were measured. RESULTS: Overweight was more common among Turkish migrants and Moroccan migrant women as compared to their Dutch counterparts. Obesity prevalence rates were more than twice as high among Turkish (39.6%) and Moroccan (39.1%) women than among Dutch women (16.5%). Controlling for level of education and unemployment attenuated ethnic differences in overweight. Abdominal obesity was more common among Turkish and Moroccan than among Dutch women. After controlling for BMI, migrant men had a relatively low waist circumference compared to Dutch men. CONCLUSION: Overweight is relatively common among Turkish and Moroccan migrants, especially women. Education and employment are relevant in explaining ethnic differences in overweight. Compared to Dutch men, migrant men seem to have a more favourable fat distribution with less abdominal fat.

Ethnic differences in total and HDL cholesterol among Turkish, Moroccan and Dutch ethnic groups living in Amsterdam, the Netherlands.

BACKGROUND: High total cholesterol and low HDL (high-density lipoprotein) cholesterol are important determinants of cardiovascular disease. Little is known about dyslipidemia among Turkish and Moroccan migrants, two of the largest ethnic minority groups in several European countries. This study examines ethnic differences in total and HDL cholesterol levels between Dutch, Turkish and Moroccan ethnic groups. METHODS: Data were collected in the setting of a general health survey, in Amsterdam, the Netherlands, in 2004. Total response rate was 45% (Dutch: 46%, Turks: 50%, Moroccans: 39%). From 1,220 adults information on history of hypercholesterolemia, lifestyle and demographic background was obtained via health interviews. In a physical examination measurements of anthropometry and blood pressure were performed and blood was collected. Total and HDL cholesterol were determined in serum. RESULTS: Total cholesterol levels were lower and hypercholesterolemia was less prevalent among the Moroccan and Turkish than the Dutch ethnic population. HDL cholesterol was also relatively low among these migrant groups. The resulting total/HDL cholesterol ratio was particularly unfavourable among the Turkish ethnic group. Controlling for Body Mass Index and alcohol abstinence substantially attenuated ethnic differences in HDL cholesterol levels and total/HDL cholesterol ratio. CONCLUSIONS: Total cholesterol levels are relatively low in Turkish and Moroccan migrants. However part of this advantage is off-set by their relatively low levels of HDL cholesterol, resulting in an unfavourable total/HDL cholesterol ratio, particularly in the Turkish population. Important factors in explaining ethnic differences are the relatively high Body Mass Index and level of alcohol abstinence in these migrant groups.

Diabetes prevalence and risk factors among ethnic minorities.

BACKGROUND: Ethnic minorities living in Western societies may have a higher prevalence of diabetes. We investigated whether the prevalence of diabetes among Turkish and Moroccan migrants differs from the indigenous urban population in the Netherlands, and whether these differences can be explained by differences in risk factors. METHODS: In 2004 a general health survey, stratified by ethnicity and age, was carried out among the population of Amsterdam. The current study included 375 Turkish, 314 Moroccan and 417 Dutch individuals aged 18-70 years. Participants underwent a physical examination and a health interview. Diabetes was based on self-report, the use of anti-diabetic medicine, blood glucose levels and HbA1c. RESULTS: The prevalence of diabetes in the Amsterdam population was significantly higher in Turkish (5.6%) and Moroccan (8.0%), compared to Dutch individuals (3.1%). These differences, which were much larger after adjustment for age, were only partly explained by the lower socioeconomic status and higher frequency of obesity among ethnic minorities. The difference between Dutch and Moroccan individuals remained significant even after adjustments for multiple risk factors. The typical age of onset of diabetes in both Turks and Moroccans is respectively one and two decades younger than in the indigenous population. CONCLUSION: Diabetes is more prevalent among Turkish and Moroccan migrants as compared to the indigenous population. Only part of this difference can be explained by differences in demographic and lifestyle risk factors.

Ethnic differences in the effect of environmental stressors on blood pressure and hypertension in the Netherlands.

BACKGROUND: Evidence strongly suggests that the neighbourhood in which people live influences their health. Despite this, investigations of ethnic differences in cardiovascular risk factors have focused mainly on individual-level characteristics. The main purpose of this study was to investigate associations between neighbourhood-level environmental stressors (crime, housing density, nuisance from alcohol and drug misuse, quality of green space and social participation), and blood pressure (BP) and hypertension among different ethnic groups. METHODS: Individual data from the Amsterdam Health Survey 2004 were linked to data on neighbourhood stressors creating a multilevel design for data analysis. The study sample consisted of 517 Dutch, 404 Turkish and 365 Moroccans living in 15 neighbourhoods in Amsterdam, the Netherlands. RESULTS: Amongst Moroccans, high density housing and nuisance from drug misuse were associated with a higher systolic BP, while high quality of green space and social participation were associated with a lower systolic BP. High level of nuisance from drug misuse was associated with a higher diastolic BP. High quality of green space was associated with lower odds of hypertension. Amongst Turkish, high level of crime and nuisance from motor traffic were associated with a higher diastolic BP. Similar associations were observed among the Dutch group but none of the differences were statistically significant. CONCLUSION: The study findings show that neighbourhood-level stressors are associated with BP in ethnic minority groups but were less evident in the Dutch group. These findings might imply that the higher BP levels found in some ethnic minority groups might be partly due to their greater susceptibility to the adverse neighbourhood environment in which many ethnic minority people live. Primary prevention measures targeting these neighbourhood stressors may have an impact in reducing high BP related morbidity and mortality among ethnic minority groups.