HowNutsAreTheDutch (HoeGekIsNL): A crowdsourcing study of mental symptoms and strengths

Abstract

HowNutsAreTheDutch (Dutch: HoeGekIsNL) is a national crowdsourcing study designed to investigate multiple continuous mental health dimensions in a sample from the general population (n = 12,503). Its main objective is to create an empirically based representation of mental strengths and vulnerabilities, accounting for (i) dimensionality and heterogeneity, (ii) interactivity between symptoms and strengths, and (iii) intra-individual variability. To do so, HowNutsAreTheDutch (HND) makes use of an internet platform that allows participants to (a) compare themselves to other participants via cross-sectional questionnaires and (b) to monitor themselves three times a day for 30 days with an intensive longitudinal diary study via their smartphone. These data enable for personalized feedback to participants, a study of profiles of mental strengths and weaknesses, and zooming into the fine-grained level of dynamic relationships between variables over time. Measuring both psychiatric symptomatology and mental strengths and resources enables for an investigation of their interactions, which may underlie the wide variety of observed mental states in the population. The present paper describes the applied methods and technology, and presents the sample characteristics. Copyright © 2015 John Wiley & Sons, Ltd.

Mental disorders as networks of problems: a review of recent insights

“…Although studies have collected ESM data in therapeutic settings to provide feedback on patterns of affect [58–60], these data have not been analyzed using network models to derive, for instance, the most central symptoms—and a large crowdsourcing study that does provide feedback via personalized dynamic networks does so only outside a therapeutic setting [61]. Merging these two approaches may provide valuable insights, and we are aware of one such pioneering case study that investigated personalized feedback based on network models within a therapeutic setting [62].…”

Feasibility of a Web-Based Cross-Over Paleolithic Diet Intervention in the General Population

“…To determine representativeness of the sample, sex, age, body mass index, marital status, number of children, educational level, and work status of participants in the present study were compared to the Dutch population using data from (Centraal Bureau voor de Statistiek, ) with t-tests for continuous variables and for categorical variables either Chi-square tests, or, in case of low numbers in one or more categories, Fisher's exact tests. Psychological symptom scores were compared to the weighed population means published by Van Der Krieke (Van Der Krieke et al, 2016), using independent samples t-tests. No comparison data from the Dutch population were available for somatic symptoms.…”

“…Especially in The Netherlands, where over 90% of households has an internet connection, the use of web-based recruitment methods does not seem a limitation for achieving a representative sample. On the other hand, samples in other studies on diet and/or psychological symptoms also contained more females and more higher educated individuals compared to the general population (see for example, Boers et al, 2014 andVan Der Krieke et al, 2016). Thus, it seems more likely that the higher number of females and higher educated participants should be attributed to the topic of the study than to the recruitment method.…”

“…The RoSI is based on the Patient Health Questionnaire-15 (Kroenke, Spitzer, & Williams, 2002), complemented with five somatization items from the Symptom Checklist (Arrindell & Ettema, 1986) and eight items derived from an expert committee supervised by J. Rosmalen. The RoSI is currently being validated using data from the HowNutsAreTheDutch study (Van Der Krieke et al, 2016). Pending the outcomes of this validation process, use of the RoSI should be seen as a possible limitation of our sample size estimations.…”

“…Reliability and validity of the Patient Health Questionnaire are moderate to good, with a Cronbach's α of 0.80, intraclass-correlation coefficients between 0.60 and 0.83, strong associations with functional status, disability days and symptom-related difficulty which were discriminative between somatic and depressive symptoms (Kroenke et al, 2002;van Ravesteijn et al, 2009). The full somatic symptoms questionnaire is currently being validated in data from the HowNutsAreTheDutch study (Van Der Krieke et al, 2016) and called the Rosmalen Somatisation Index (RoSI).…”