Background: Translating scores to a common metric provides advantages that support the applied collaborative care model in the Netherlands. McCall's T-score is frequently used, and the optimal...Show moreBackground: Translating scores to a common metric provides advantages that support the applied collaborative care model in the Netherlands. McCall's T-score is frequently used, and the optimal approach to obtain this score is through Item Response Theory (IRT). However, IRT is complicated, requires dedicated software, and a large dataset. This study aimed to validate an alternative procedure to obtain T-scores from IRT. Methods: This study used data from an existing study, which comprised a population-based sample and a patient sample. We estimated the relation between raw scores and IRT-based T-scores with curve fitting and established conversion formulas to transform raw scores into calculated T-scores. We illustrated the process with raw scores from the Beck Depression Inventory, the Inventory of Depressive Symptomatology - Self Rated, and the Montgomery-Åsberg Depression Rating Scale. We performed a correlational analysis to assess the validity of the calculated T-scores. We also determined cut-off values using ROC analysis. Results: The curve-fitting procedure resulted in third-order polynomial regression equations to use as conversion formulas. The validity of calculated T-scores was supported by their high correlation with theta-based T-scores. ROC analysis provided cut-off values, which were comparable to the previous studies, using raw scale scores. Conclusion: The curve-fitting procedure yielded sufficiently valid calculated T-scores for all instruments in comparison to the theta-based T-scores from IRT. The resulting cut-off values demonstrated that calculated T-scores were able to distinguish patients from the general population. The practical use of the results is discussed.Show less
Background: Post-traumatic stress disorder (PTSD) has been associated with impairments across cognitive abilities. While some prior work suggests that the PTSD symptom domain of intrusion may be...Show moreBackground: Post-traumatic stress disorder (PTSD) has been associated with impairments across cognitive abilities. While some prior work suggests that the PTSD symptom domain of intrusion may be most strongly related to cognitive impairment, little is known about the relation of cognitive functioning with individual PTSD symptoms or other symptom domains, and the temporal stability of such relations. The current study addresses these questions. Methods: Data were analysed from 1,484 trauma-exposed U.S. military veterans (Mdn=65 years) who participated in the National Health and Resilience in Veterans Study (NHRVS). We estimated four regularised partial correlation networks of DSM-5 PTSD symptoms at baseline (past month or lifetime) and cognitive functioning at baseline and three-year follow-up, respectively. Network comparison tests examined temporal stability, and sensitivity analyses the robustness of the associations. Results: Across network models, difficulty concentrating and trouble experiencing positive feelings consistently showed unique negative relations to cognitive functioning. Contrary to expectations, the symptom domains of alterations in arousal and reactivity, as well as cognition and mood were more strongly linked to cognitive functioning than the other two domains. Network structures and overall strength did not significantly differ between cross-sectional and longitudinal networks. Conclusion: Overall, we highlight the importance of links between PTSD symptoms and symptom domains on the one hand, and cognitive functioning on the other—relations obfuscated by modelling only PTSD diagnosis or sum score. Given that longitudinal processes between the two constructs appear to be present, we recommend monitoring of cognitive functioning and integrating it into clinical care of PTSD.Show less
Background. Student populations show higher prevalence rates of procrastination and symptoms of stress, anxiety and depression compared to the general population. Previous research found evidence...Show moreBackground. Student populations show higher prevalence rates of procrastination and symptoms of stress, anxiety and depression compared to the general population. Previous research found evidence for an association between mental health and procrastination. The current study investigated the association of procrastination with mental health problems using the network perspective and dealt with the question whether procrastination is a state or a trait. Methods. We used Ecological Momentary Assessment (EMA) to collect data from 79 undergraduate students from Dutch universities. Our participants answered questions concerning procrastination and symptoms of stress, anxiety and depression four times a day over a time course of two weeks. We estimated contemporaneous and temporal networks to gain insight in the dynamic connections between these constructs. Moreover, we assessed procrastination with a questionnaire before and after two weeks and compared both assessments in order to investigate if procrastination categorizes as a state or a trait. Results. We found significant contemporaneous associations of procrastination with symptoms of anxiety and depression and a temporal association between procrastination and anxiety. Pre- and posttest on procrastination did not differ significantly. Conclusions. Symptoms of anxiety and depression co-occur at the same point in time and procrastination is a predictor for anxiety symptoms. The pre- and posttest results indicated no change of procrastination over time. However, the dynamic network analysis indicated fluctuations of procrastination over time and situation. We concluded that procrastination exists at trait and state level. It is important to mention that data collection took place during the Covid-19 outbreak.Show less
Previous research has investigated the association between hunger and mental health. Although constructs such as stress, anxiety and depression have been indeed found to be related to appetite,...Show morePrevious research has investigated the association between hunger and mental health. Although constructs such as stress, anxiety and depression have been indeed found to be related to appetite, results are often contradictory and point to different causal directions. The present study investigates such associations in a student population of 84 individuals, by means of an Ecological Momentary Assessment (EMA) method. Participants’ perceived levels of stress, anxiety, depression and hunger were recorded four times per day, during a two-weeks period. In addition, before accessing the study, students had to fill in a baseline assessment, which allowed for a further investigation of the relationship between trait and state hunger. A network approach was utilized for the first statistical analysis, allowing for the depiction of contemporaneous, temporal and between-subjects network, whilst a linear regression analysis was used to compare hunger data at baseline and during EMA. Results failed to replicate previous findings concerning appetite and mental health, as for all networks, hunger was not associated with any other variable of interest. However, we were able to identify a linear relationship between trait and state hunger, with the former being a significant positive predictor of the latter.Show less
Background: Research indicates that probiotics, specific strains of beneficial bacteria, are beneficial against anxiety and depression. There are indications that a potential mechanism behind this...Show moreBackground: Research indicates that probiotics, specific strains of beneficial bacteria, are beneficial against anxiety and depression. There are indications that a potential mechanism behind this might be that probiotics alter interoception and the way we respond to our body needs, which is reflected in interoception. Both critically influence anxiety and depression. Objective: The present study aimed to test whether administering probiotics over a period of four weeks increases the degree of interoception and adaptive responding to body needs in healthy individuals. Also, anxiety and depression were measured. Confirming an increase in the degree of interoception and adaptive responding would show that probiotics trigger a mechanism that reduces anxiety and depression. Design: The study was set up as a randomized, tripleblinded, placebo-controlled within/between subject (placebo versus probiotics), pre- and postintervention assessment design. 89 healthy participants without diagnosed mood or anxiety disorders, aged 18-35 years, received multispecies (diverse strains) probiotics or placebo supplementation over four weeks. In the pre- and post-intervention, degree of interoceptive awareness, adaptive responses, depression, and anxiety. Results: There were no significant changes on any measure, but one unexpected decrease in adaptive responding for the probiotics group. Conclusion: It cannot be concluded that probiotics increase the degree of interoceptive awareness and adaptive responding. Moreover, the results suggest that anxiety and depression are not influenced by probiotics in a healthy sample. However, insights from other research suggests that the effect might be stronger in a depressed and anxious sample. Further research is needed to see whether probiotics might affect interoception and adaptive responding differently in depressed and anxious individuals.Show less
According to the WHO, depression is one of the major causes of disability worldwide. However, the understanding of the disorder remains incomplete. Recently, antibiotic use has been associated with...Show moreAccording to the WHO, depression is one of the major causes of disability worldwide. However, the understanding of the disorder remains incomplete. Recently, antibiotic use has been associated with the onset of mood disorders. It is assumed that microbiota-gut-brain interactions are partly managed by the immune system. Accordingly, this study aimed to clarify the correlations between antibiotic-induced microbial dysbiosis, cognitive reactivity to sad mood (CRSM), and concentration of the antibody secretory immunoglobulin A (sIgA). Participants, which finished an antibiotic treatment within the past three months (n = 47), were compared to control participants (n = 60). Participants’ CRSM was measured using the Leiden Index of Depression Sensitivity (LEIDS-R). Antibody levels of salivary sIgA were investigated by obtaining saliva samples from the participants. Results indicated that antibiotic use was not associated with remarkable differences in sIgA concentration or depression sensitivity, i.e. CRSM. However, based on exploratory observations the preliminary idea of antibiotic use resulting in sex-specific responses was developed and is proposed valuable to be investigated in future research. Moreover, it was examined if antibiotic use can be considered a moderator in the relation between sIgA concentration and CRSM. Antibiotic use did not display a moderating role and CRSM was not predicted by sIgA concentration. The findings within this study were limited by a reduced dataset of sIgA concentrations. Ultimately, in contrast to the hypothesized outcome antibiotic-induced microbial dysbiosis was not associated with a decreased sIgA concentration or increased depression sensitivity of healthy individuals within this study. To clarify the correlation between the microbiota-immune-brain axis, antibiotic use, and mental health future research is needed.Show less
Background. Anger is experienced in various mental disorders. Based on increased mental health problems in students and the adversity of the coronavirus pandemic, (1) the relations between anger,...Show moreBackground. Anger is experienced in various mental disorders. Based on increased mental health problems in students and the adversity of the coronavirus pandemic, (1) the relations between anger, depression, anxiety, stress, and being occupied with COVID-19 were explored. As traits predict interpersonal events and states identify events under situational control, it was investigated (2) if baseline trait anger predicted average state anger during a period of self-isolation to test if anger levels were determined by general tendencies, and (3) if trait and average state anger differed within and between men and women to test if the groups were affected differently by situational factors. Methods. (1) Ecological Momentary Assessment (EMA) data was collected from 79 undergraduates from Dutch universities, with surveys prompted via smartphone four times daily for 14 days. Contemporaneous, temporal, and between-subjects networks were computed. (2) In a multiple regression analysis, average EMA state anger was regressed on trait anger while controlling for gender, age, depression, anxiety, and stress. (3) A mixed-design analysis of covariance included standardized type of anger as a within-factor and gender as a between-factor while controlling for differences in mental health. Results. (1) Contemporaneously, anger was positively associated with irritability, feeling nervous and anhedonia. Temporally, anger and irritability positively predicted each other. Anger positively predicted difficulty to relax and itself. Between-subjects, anger was positively associated with irritability and feeling nervous but negatively with being occupied with COVID-19. (2) Trait anger did not significantly predict average EMA anger, whereas the covariate stress did. (3) Despite significantly lower trait anger compared to women, men displayed significantly increased average EMA anger in relation to their trait levels. Trait and average EMA anger did not differ within women. Conclusion. EMA anger was persistently related to stress, less likely to be the source or recipient of activation compared to other constructs, not strongly linked to trait, and increased in relation to trait levels only in the male group. Differences between our healthy participants and a clinical sample encourage an investigation of anger in phase transitions towards psychopathology and its potentially adaptive effects in healthy individuals.Show less
