The Four-Dimensional Symptom Questionnaire (4DSQ) in the general population: scale structure, reliability, measurement invariance and normative data: a cross-sectional survey

Measuring the psychological burden of women with pelvic floor complaints: The psychometric characteristics of a new instrument

Background

To be able to optimize pelvic healthcare, it would be helpful to specifically assess women's psychological burden with pelvic floor complaints. In the absence of such an instrument, a new instrument was developed to measure this burden in women who seek help. In previous research, a comprehensive overview was yielded of women's restrictions and distress with pelvic floor complaints, and a conceptual model was developed of seven types of distress that were reflected by 33 statements. The present study was performed to investigate the psychometric properties of the new instrument, termed the Pelvic Floor Complaint-related Psychological Burden Inventory (PFC-PBI).

Methods

In an online survey data was collected from women with and without pelvic floor complaints on the 33 statements. The internal consistency of the types of distress was tested using item-total correlation analysis, Principal Component and Confirmatory Factor Analyses were performed, and the convergent and divergent validity of the types of distress was examined against existing questionnaires using the Multi-Trait Multi-Method methodology.

Results

Based on the factor analyses, a 10-item instrument was tested. Outcomes show excellent internal consistency of this instrument, comprising a single component. The PFC-PBI demonstrated satisfactory convergent and divergent validity.

Conclusions

This new measure appears to be a promising tool to inventory the psychological burden of women suffering from pelvic floor complaints. Research into its further development, implementation, and clinical use appears warranted.

Sexual functioning is not, but psychological burden is predictive for receiving help in pelvic physical therapy practice: A cross-sectional study

Background

Pelvic floor complaints are common among women and often accompanied by sexual dysfunction and psychological burden. They are also associated with pregnancy and childbirth. However, not all women with these complaints receive help in pelvic physical therapy practice. This study explored if pregnancy, parity, pelvic floor complaints, sexual functioning, and psychological burden are predictive of receiving help in pelvic physical therapy practice.

Methods

In a cross-sectional exploratory design, women completed an online survey about pelvic floor complaints, sexual function, and psychological burden. Binary logistic analysis was used to analyze the predictive value of the above-mentioned factors.

Results

Data from 542 participants were analyzed. Pregnancy and parity, PFC severity, psychological burden, and the interaction between pelvic floor complaints and psychological burden were significant predictors of receiving help. Against expectations, sexual functioning was not predictive of receiving help.

Conclusions

Women's psychological burden is an important factor in determining if or when women receive help in PPT practice. More research is needed to unravel the role of sexual functioning in the context of pelvic floor complaints and women's psychological burden. More insight into this area of expertise could possibly improve and enhance pelvic health care for women with pelvic floor complaints.

Cohort profile: Netherlands Longitudinal Study on Hearing (NL-SH)

PURPOSE

The Netherlands Longitudinal Study on Hearing (NL-SH) was set up to examine associations of hearing ability with psychosocial, work and health outcomes in working age adults.

PARTICIPANTS

Inclusion started in 2006 and is ongoing. Currently the sample comprises 2800 adults with normal and impaired hearing, aged 18-70 years at inclusion. Five-year follow-up started in 2011, 10-year follow-up in 2016 and 15-year follow-up in 2021. All measurements are web-based. Participants perform a speech-in-noise recognition test to measure hearing ability and fill out questionnaires about their hearing status, hearing aid use, self-reported hearing disability and coping, work status and work-related outcomes (work performance, need for recovery), physical and psychosocial health (depression, anxiety, distress, somatisation, loneliness), healthcare usage, lifestyle (smoking, alcohol), and technology use.

FINDINGS TO DATE

The NL-SH has shown the vast implications of reduced hearing ability for the quality of life and health of working-age adults. A selection of results published in 27 papers is presented. Age-related deterioration of hearing ability accelerates after the age of 50 years. Having a history of smoking is associated with a faster decline in hearing ability, but this relationship is not found for other cardiovascular risk factors. Poorer hearing ability is associated with increased distress, somatisation, depression and loneliness. Adults with impaired hearing ability are more likely to be unemployed or unfit for work, and need more time to recuperate from work effort.

FUTURE PLANS

Participant data will be linked to a national database to enable research on the association between hearing ability and mortality. Linking to environmental exposure data will facilitate insight in relations between environmental factors, hearing ability and psychosocial outcomes. The unique breadth of the NL-SH data will also allow for further research on other functional problems, for instance, hearing ability and fall risk.

TRIAL REGISTRATION NUMBER

NL12015.029.06.

A Common Measurement Scale for Self-Report Instruments in Mental Health Care

Abstract. The diversity of measures in clinical psychology hampers a straightforward interpretation of test results, complicates communication with the patient, and constitutes a challenge to the implementation of measurement-based care. In educational research and assessment, it is common practice to convert test scores to a common metric, such as T scores. We recommend applying this also in clinical psychology and propose and test a procedure to arrive at T scores approximating a normal distribution that can be applied to individual test scores. We established formulas to estimate normalized T scores from raw scale scores by regressing IRT-based θ scores on raw scores. With data from a large population and clinical samples, we established crosswalk formulas. Their validity was investigated by comparing calculated T scores with IRT-based T scores. IRT and formulas yielded very similar T scores, supporting the validity of the latter approach. Theoretical and practical advantages and disadvantages of both approaches to convert scores to common metrics and alternative approaches are discussed. Provided that scale characteristics allow for their computation, T scores will help to better understand measurement results, which makes it easier for patients and practitioners to use test results in joint decision-making about the course of treatment.

Head-to-head comparison of somatic symptom scales: The Patient Health Questionnaire (PHQ-15) and the somatization scale of the Four-Dimensional Symptom Questionnaire (4DSQ-S)

OBJECTIVE

The goal of this study was to compare the 15-item Patient Health Questionnaire (PHQ-15) and the somatization subscale of the Four-Dimensional Symptoms Questionnaire (4DSQ-S) with respect to their latent structure and reliability, and to examine whether their scores are affected by age and gender, and whether the scales measure the same construct(s).

METHODS

The study population consisted of individuals with a tendency to experience persistent somatic symptoms, recruited in multiple healthcare settings, who completed the PHQ-15 and 4DSQ-S concurrently. We analyzed the scales' latent factor structure using confirmatory factor analysis (CFA), the scales' reliability, and differential item functioning (DIF) due to age and gender. We performed a head-to-head comparison by fitting structural equation models of the questionnaires' factors.

RESULTS

We included 234 participants. CFA showed that both questionnaires fitted a bifactor model with a general factor and four specific factors, three of which (labeled "musculoskeletal", "gastrointestinal", and "cardiopulmonary") were substantively similar. Both scales were essentially unidimensional. The reliability of the PHQ-15 and 4DSQ-S was equally high (omega 0.933 and 0.942, respectively). DIF-analysis showed minor DIF for age in one item of each questionnaire, with negligible impact on the scale score. Head-to-head comparison showed that the PHQ-15 and 4DSQ-S measured the same constructs. We present PHQ-15 - 4DSQ-S cross-walk tables.

CONCLUSIONS

Both questionnaires mainly measure a single somatic symptom burden dimension of which all symptoms (covered by the questionnaires) are adequate indicators. They do so equally accurately and they behave the same across gender and age categories.

Factors Associated With the Development of Tinnitus and With the Degree of Annoyance Caused by Newly Developed Tinnitus

OBJECTIVES

Tinnitus is highly prevalent, but only a few risk factors for developing tinnitus are known and little is known about factors associated with the degree of annoyance of new-onset tinnitus. Longitudinal analysis can reveal risk factors associated with the development of tinnitus and might lead to targeted prevention. The aim of this study is twofold. (1) To identify risk factors that are longitudinally associated with the odds of developing tinnitus 5 years later. (2) To identify factors that are cross-sectionally associated with tinnitus annoyance in adults with new-onset tinnitus.

METHODS

Baseline, 5-year, and 10-year follow-up data of participants in the Netherlands Longitudinal Study on Hearing (NL-SH) were used. The NL-SH is a web-based prospective cohort study, which started in 2006 and includes both normal hearing and hearing-impaired adults aged 18 to 70 years at baseline. The NL-SH uses an online digit-triplet speech-in-noise test to asses speech recognition ability in noise, and online questionnaires on various aspects of life. At follow-up, participants are asked (1) if they suffer from tinnitus and (2) to rate tinnitus annoyance on a 0 to 100 numeric rating scale. We investigated whether demographic (age, sex, living arrangement, educational level), lifestyle (history of tobacco smoking, alcohol use), health (asthma, severe heart disease, hypertension, history of stroke, osteoarthritis, rheumatoid arthritis, epilepsy, multiple sclerosis, and migraine), hearing (speech recognition ability in noise, hyperacusis, and occupational noise exposure), and psychological variables (distress, somatization, depression, and anxiety) were potential risk factors for new-onset tinnitus, or associated with annoyance caused by new-onset tinnitus. Generalized estimating equations were used to longitudinally analyze the association between potential risk factors and new-onset tinnitus measured 5 years later. A multivariable association model was constructed using a forward selection procedure with p < 0.05 for model entry. Linear regression analysis was used to cross-sectionally analyze the association between potential factors and tinnitus annoyance in new-onset tinnitus. For this purpose, a multivariable association model was constructed using a forward selection procedure with p <0.05 for model entry.

RESULTS

In total, 734 participants without tinnitus at baseline were included, from which 137 participants reported to suffer from new-onset tinnitus 5 or 10 years later. Risk factors for new-onset tinnitus were history of smoking (odds ratio 1.5, 95% confidence interval [CI] 1.0 to 2.2, p = 0.027) and higher levels of somatization (odds ratio 2.0, 95% CI 1.2 to 3.3, overall p = 0.024). Factors associated with the degree of tinnitus annoyance were increased levels of anxiety (β = 11.6, 95% CI 2.3-20.8, overall p = 0.035) and poor speech recognition ability in noise (β = 13.5, 95% CI, 4.4 to 22.6, overall p = 0.014).

CONCLUSIONS

Higher levels of somatization and a history of smoking were found to be risk factors for new-onset tinnitus 5 years later. Anxiety and poor speech recognition ability in noise were associated with higher degrees of tinnitus annoyance in new-onset tinnitus. Somatization deserves to be addressed in future research and clinical practice as it might provide part of a model for the development of chronic tinnitus.

Neuroimaging in Breast Implant Illness: An fMRI Pilot Study

BACKGROUND

Some women with breast implants report systemic and cognitive symptoms known as breast implant illness (BII), which are very similar to those of fibromyalgia. Functional MRI (fMRI) has shown altered brain activity in fibromyalgia patients.

OBJECTIVES

The aim of this pilot study was to investigate whether brain alterations could be observed in BII patients by fMRI.

METHODS

Women aged 18 to 76 with silicone breast implants for cosmetic reasons were recruited through a Dutch online BII support organization (MKS) and through the Maastricht University Medical Center. Study participants comprised 12 women with BII and 12 women without symptoms. Participants completed questionnaires regarding demographic characteristics, medical history, psychosocial complaints (Four-Dimensional Symptom Questionnaire), cognitive failure (Mini-Mental State Examination), and pain intensity and pain-related disability (Chronic Pain Grade Scale). Subsequently, brain images of all participants were obtained by resting-state fMRI and diffusion tensor imaging in a 3-T MRI scanner (Siemens Medical System, Erlangen, Germany).

RESULTS

Eleven BII patients and 12 healthy controls were included in the analysis. Baseline characteristics were similar in the 2 groups and the mean silicone exposure was 15 years. Patients scored significantly higher than controls on both pain intensity and disability. Patients scored worse on depression, somatization, distress, and anxiety compared with asymptomatic women. Mini-Mental State Examination scores were normal. However, the analyses of both functional connectivity and structural integrity showed no significant differences between the 2 groups.

CONCLUSIONS

This pilot study showed no evidence of brain alterations in BII patients. However, patients scored significantly worse on psychosocial symptoms than controls. Psychological factors appear to play an important role in BII and should be further investigated.

LEVEL OF EVIDENCE: 2

Role of resilience in healthcare workers' distress and somatization during the COVID-19 pandemic: A cross-sectional study across Flanders, Belgium

AIM

To evaluate the impact and the possible role of psychological resilience in the COVID-19 pandemic outbreak on healthcare workers' mental and physical well-being in Belgium.

DESIGN

This cross-sectional, survey-based study enrolled 1376 healthcare workers across Belgium from 17 April 2020 to 24 April 2020.

METHODS

The study sample consisted of direct care workers (nurses and doctors), supporting staff and management staff members. The main outcomes are resilience, distress and somatization.

RESULTS

Higher educational level was associated with lower symptoms of distress and somatization. Physicians exhibited the lowest risk of experiencing heightened levels of distress and somatization. Controlling for confounding factors, higher levels of resilience were associated with a 12% reduced chance of increased distress levels and 5% lower chance of increased somatization levels. Our results suggest the potentially buffering role of mental resilience on those working on the frontline during the COVID-19 pandemic outbreak.

Uptake of Hearing Aids and Hearing Assistive Technology in a Working Population: Longitudinal Analyses of The Netherlands Longitudinal Study on Hearing

OBJECTIVE

To identify predictors of the 5-year uptake of hearing aids (HAs) and hearing assistive technology (HAT) in a sample of Dutch employees eligible for HAs and/or HAT. The potential predictors included demographic factors (age, sex, marital status, and living situation), education, hearing factors (ability to recognize speech in noise and self-reported hearing disability), distress, self-efficacy, and work-related factors (job demand, job control, and need for recovery).

DESIGN

Five-year follow-up data of the Netherlands Longitudinal Study on Hearing (NL-SH) collected until January 2019 were included. An online digit-triplet in noise test, the National Hearing Test (NHT), was used to assess speech-recognition-in-noise ability. In addition, online questionnaires on demographic, socioeconomic, self-reported hearing disability, health, and work-related characteristics were administered. Adults who worked over 12 hours per week, who had not yet taken up HAs or HAT, but who would be eligible for HAs/HAT based on their NHT score (insufficient or poor hearing ability), were included in the study. The 5-year uptake of HAs/HAT was defined as a dichotomous variable of self-reported HA/HAT use reported 5 years later. Generalized Estimating Equations analyses were performed to analyze the associations between potential predicting factors and the 5-year uptake of HAs/HAT, taking into account the repeated measurements of the predicting factors and the 5-year uptake of HAs/HAT.

RESULTS

Data of 218 participants were included. The cumulative incidence of the 5-year uptake of HAs/HAT was 15 to 33%, of which 52 employees took up HAs and 11 employees took up HAT. Married participants had increased odds for 5-year uptake of HAs/HAT compared with unmarried participants (odds ratio [OR] = 2.13, 95% confidence interval [CI] = 1.05 to 4.35). Higher self-reported hearing disability (per one unit, scale range 0 to 74) was associated with increased odds for 5-year uptake of HAs/HAT (OR = 1.05, 95% CI = 1.03 to 1.07). Job demand showed a significant interaction with sex (p = 0.002), and therefore, stratified analyses were performed. In male participants, participants with higher job demand scores (per one unit, scale range 12 to 48) had increased odds for 5-year uptake of HAs/HAT (OR = 1.18, 95% CI = 1.05 to 1.35). No difference was seen in females.

CONCLUSION

This study confirms that factors predicting the uptake of HAs/HAT in the general or older populations, including marital status and self-reported hearing disability, also extend to the working population. The identification of job demand as a predictor of the uptake of HAs/HAT (in males only) was a novel finding. It demonstrates the importance of considering work-related factors in aural rehabilitation.

The Role of Coping Behavior in Healthcare Workers' Distress and Somatization During the COVID-19 Pandemic

Background: Constantly searching for a balance between work demands and their own physical and psychological health has challenged medical and nursing staff during the immediate wake of this COVID-19 viral epidemic leading to acute stress reactions and psychosomatic symptoms. Coping behavior might be a buffer for work-related stress in relation to mental well-being. The present study aims to evaluate the role of positive and negative stress-reducing activities on healthcare workers' mental and physical well-being. Methods: This was a cross-sectional study using an online survey that was sent out using our network of healthcare workers at the University of Antwerp and through social media. Socio-demographic data, coping behavior with the Palliative Pallet Scale (P3), and distress and somatization using the Four-dimensional symptom checklist were collected. Surveys were completed by 1,376 participants. Results: The results clearly showed that positive stress-reducing activities are related to fewer symptoms of distress and somatization. Providing direct care to COVID-19 patients was associated with a higher decrease of applying positive stress-reducing activities during the peak of the pandemic compared to the ideal situation. Finally, fewer symptoms of distress and somatization were associated with the following activities: reading, mind sports games, keeping a hobby collection, studying; engaging in sexual activities with your partner; cleaning the house, tidying up, working in the garden, doing household chores; exercising alone; walking, or taking a trip together with someone; exercise together with someone; watching TV, listening/playing (to) music/, playing computer games; playing a card game or other board game; and preparing something extra tasteful outside regular meals. Conclusion: Our study demonstrated an association between concrete coping behaviors and distress and somatization in healthcare workers during the first peak of the COVID-19 pandemic. The results provide relevant and additional insights to develop and investigate interventions among others in personal leadership and resilience.

Limited predictive value of illness perceptions for short-term poor recovery in musculoskeletal pain. A multi-center longitudinal study

Background

Musculoskeletal pain (MSP) is recognized worldwide as a major cause of increased years lived with disability. In addition to known generic prognostic factors, illness perceptions (IPs) may have predictive value for poor recovery in MSP. We were interested in the added predictive value of baseline IPs, over and above the known generic prognostic factors, on clinical recovery from MSP. Also, it is hypothesized there may be overlap between IPs and domains covered by the Four-Dimensional Symptom Questionnaire (4DSQ), measuring distress, depression, anxiety and somatization. The aim of this study is twofold; 1) to assess the added predictive value of IPs for poor recovery and 2) to assess differences in predictive value for poor recovery between the Brief Illness Perception Questionnaire - Dutch Language Version (Brief IPQ-DLV) and the 4DSQ.

Methods

An eligible sample of 251 patients with musculoskeletal pain attending outpatient physical therapy were included in a multi-center longitudinal cohort study. Pain intensity, physical functioning and Global Perceived Effect were the primary outcomes. Hierarchical logistic regression models were used to assess the added value of baseline IPs for predicting poor recovery. To investigate the performance of the models, the levels of calibration (Hosmer-Lemeshov test) and discrimination (Area under the Curve (AUC)) were assessed.

Results

Baseline ‘Treatment Control’ added little predictive value for poor recovery in pain intensity [Odds Ratio (OR) 0.80 (Confidence Interval (CI) 0.66–0.97), increase in AUC 2%] and global perceived effect [OR 0.78 (CI 0.65–0.93), increase in AUC 3%]. Baseline ‘Timeline’ added little predictive value for poor recovery in physical functioning [OR 1.16 (CI 1.03–1.30), increase in AUC 2%]. There was a non-significant difference between AUCs in predictive value for poor recovery between the Brief IPQ-DLV and the 4DSQ.

Conclusions

Based on the findings of this explorative study, assessing baseline IPs, over and above the known generic prognostic factors, does not result in a substantial improvement in the prediction of poor recovery.

Also, no recommendations can be given for preferring either the 4DSQ or the Brief IPQ-DLV to assess psychological factors.

Validation of the Four-Dimensional Symptom Questionnaire (4DSQ) in a mental health setting

Mental health problems are highly prevalent in primary care. Validated tools to detect mental disorders in general practice are needed. The Four-Dimensional Symptom Questionnaire (4DSQ) was designed to help GPs differentiating between psychological distress and psychopathological conditions (depression, anxiety, somatization). The aim of the current study was to examine psychometric properties of the 4DSQ in a mental health setting. Reliability, factorial, construct, and criterion validity of the English translation of the 4DSQ were analyzed in an American sample of 159 patients attending a psychotherapy outpatient clinic. Measurement equivalence across languages was determined by analyzing differential item functioning (DIF) and differential test functioning (DTF) in the American sample and a Dutch mental health sample, matched by age and sex. A confirmatory factor analysis confirmed all 4DSQ subscales to be unidimensional. All 4DSQ subscales revealed excellent reliability (Cronbach's alpha and McDonald omega ≥.90) and high correlations with a symptom distress subscale of an instrument that is commonly used to monitor psychotherapy progress, the Outcome Questionnaire-45. Eight items were flagged with DIF. The Depression subscale was free of DIF. DTF analyses showed an impact of DIF on scale level for the lower cutoff score of the Distress scale. The 4DSQ Distress score was the best predictor of a mood disorder diagnosis and the Anxiety score outperformed other 4DSQ scales to predict an anxiety disorder. In conclusion, the 4DSQ demonstrates excellent reliability and validity in a mental health setting. Further research is needed to determine reliable cutoff values on 4DSQ subscales to predict psychiatric diagnoses.

Fear at the time of the COVID-19 pandemic: validation of the Arabic version of the Four-Dimensional Symptom Questionnaire among Saudi-based respondents

BACKGROUND

The COVID-19 pandemic has caused unprecedented stress and fear throughout the world.

AIMS

To evaluate the psychological effects of the COVID-19 pandemic on the Saudi public, and to examine the performance of the Arabic version of the Four-Dimensional Symptom Questionnaire (4DSQ) scale.

METHOD

We conducted an online questionnaire-based cross-sectional survey of a sample of the Saudi public.

RESULTS

The study included 347 participants, who reported significantly higher levels of distress, depressive symptoms, anxiety symptoms and somatisation compared with a normative sample. Females scored higher in terms of somatisation, depression and anxiety symptoms, and distress. Obtaining COVID-19 information from friends and relatives was associated with higher levels of somatisation, depression and anxiety symptoms, and distress. Cronbach's alpha was 0.93 for the distress scale, 0.88 for the depression scale, 0.88 for the anxiety scale and 0.86 for the somatisation scale.

CONCLUSIONS

Levels of psychological distress were high among the Saudi public during the COVID-19 pandemic. We found high reliability for the Arabic version of the 4DSQ scale. However, three items did not conform to the four-factor structure, namely, item 1: 'During the past week, did you suffer from dizziness or feeling light-headed?', item 20: 'During the past week, did you suffer from disturbed sleep?' and item 46: 'During the past week did you ever think I wish I was dead?'.

Convergent Validity of the Central Sensitization Inventory in Chronic Whiplash-Associated Disorders; Associations with Quantitative Sensory Testing, Pain Intensity, Fatigue, and Psychosocial Factors

OBJECTIVE

Central sensitization is present in different pain conditions, including chronic whiplash-associated disorders. In the absence of a gold standard method of assessment to determine the presence of central sensitization, quantitative sensory testing is currently understood as an optimal proxy. Laboratory sensory testing is, however, not feasible in clinical practice, and the Central Sensitization Inventory was developed as an alternative. The aim of the current study was to evaluate the convergent validity of the Central Sensitization Inventory in chronic whiplash-associated patients by determining the association between the Central Sensitization Inventory and quantitative sensory testing, pain intensity, fatigue, and psychosocial factors.

METHODS

A total of 125 chronic whiplash-associated patients completed multiple questionnaires and were subjected to pressure pain thresholds and temporal summation.

RESULTS

. The Central Sensitization Inventory showed a strong association with constructs of general psychopathology, anxiety, distress, depression, and somatization in chronic whiplash-associated disorders. Moderate correlations were found with fatigue and intrusive and avoidant phenomena after a variety of traumatic events. No significant association was found between the Central Sensitization Inventory and pressure pain thresholds and temporal summation, nor between the Central Sensitization Inventory and other pain measurements.

CONCLUSIONS

Overall, we found that the Central Sensitization Inventory is better in identifying the psychosocial factors related to central sensitization in chronic whiplash-associated disorders than the central nervous system adaptations. Thus, the convergent validity of the Central Sensitization Inventory appears to be only partially present in chronic whiplash-associated disorders.

Illness perceptions as an independent predictor of chronic low back pain and pain-related disability: a prospective cohort study

OBJECTIVES

To investigate whether illness perceptions, measured with the Brief Illness Perception Questionnaire, are an independent predictor of chronic low back pain and pain-related disability at 12 weeks.

DESIGN

A prospective, observational cohort study.

SETTING

26 outpatient primary care physiotherapy practices throughout the Netherlands.

PARTICIPANTS

Acute nonspecific low back pain patients between the age of 18 and 60 years, with or without radiating pain, and a pain-free episode of at least three months before onset.

INTERVENTIONS

Standard physiotherapy care according to Dutch clinical practice guidelines.

OUTCOME MEASURE

Chronic low back pain defined as pain ≥3/10 on the Numeric Pain Rating Scale and as pain-related disability ≥19/70 on the Pain Disability Index measured after 12 weeks.

RESULTS

Two hundred and four people with acute nonspecific low back pain completed both assessments. In the multivariable analyses, adjusted for pain intensity, disability, duration, radiating pain, depressed mood, associations of illness perceptions were OR 1.04 (95% CI: 1.01 to 1.08) for pain and 1.04 (95% CI: 0.99 to 1.09) for pain-related disability.

CONCLUSIONS

Illness perceptions independently predicted chronic low back pain but not pain-related disability at 12 weeks. The added predictive value of illness perceptions was relatively low.

Assessing measurement equivalence of the Danish and Dutch Four-Dimensional Symptom Questionnaire using differential item and test functioning analysis

Aims: The Dutch Four-Dimensional Symptom Questionnaire (4DSQ) measures distress, depression, anxiety and somatisation, facilitating the distinction between stress-related problems and psychiatric disorder in primary and occupational health care. The aim of the study was to examine the measurement equivalence across the Danish and Dutch 4DSQ. Methods: Danish 4DSQ data were obtained from a cohort of Danish citizens on sick leave for mental-health problems. Dutch 4DSQ data were obtained from a cohort of Dutch employees on sick leave and a cohort of general practice attenders suspected of having mental-health problems. The study samples were matched on age and sex. The 4DSQ scales were assessed for essential unidimensionality using confirmatory factor analysis. Measurement equivalence of the 4DSQ across the groups was assessed using differential item and test functioning (DIF and DTF) analysis. Results: The study groups each consisted of 1363 people (63% female, M_age=42 years). The 4DSQ scales proved essentially unidimensional. DIF was detected in 20 items. In terms of Cohen’s effect size, DIF was mostly small or moderate. In terms of effect size, the mean effect on the scale score (DTF) was negligible. Nevertheless, it is recommended to adjust some of the cut-off points for two Danish 4DSQ scales to retain the meaning of these cut-off points in Dutch respondents. Conclusions:The Danish version of the 4DSQ measures the same constructs as the original Dutch questionnaire. Twenty items functioned differently in Danish respondents than in Dutch respondents, but this had only a small impact on the scale scores.

Illness perceptions associated with patient burden with musculoskeletal pain in outpatient physical therapy practice, a cross-sectional study

INTRODUCTION

Musculoskeletal pain (MSP) is a burden to patients and to society. In addition to well-known prognostic factors, illness perceptions (IPs) may be associated with pain intensity and physical functioning in MSP but their role is not fully understood. Our research focused on these questions: 1) Do IPs differ between patients with acute, sub-acute and persistent MSP 2) Are IPs, in addition to well-known prognostic factors, associated with pain intensity and with limitations in physical functioning?

METHODS

Eligible MSP patients from 29 physical therapy practices were invited to participate in a cross-sectional study. IPs were measured with the Brief IPQ-DLV. We compared IPs between patients with acute, sub-acute and persistent MSP (1-way ANOVA with Tukey post-hoc tests). Secondly, associations between IPs with pain intensity and physical functioning were assessed (multiple linear regression).

RESULTS

With 658 participants, most IP dimensions showed small differences between acute, sub-acute or persistent pain. For pain intensity, the IP dimensions Consequences, Identity and Comprehensibility explained an additional 13.3% of the variance. For physical functioning, the dimensions Consequences, Treatment Control, Identity and Concern explained an additional 26.5% of the variance.

DISCUSSION/CONCLUSION

Most IP dimensions showed small differences between acute, sub-acute or persistent pain. In addition to some well-known prognostic variables, higher scores on some IP dimensions are associated with higher pain intensity and more limitations in physical functioning in patients with MSP. Longitudinal studies are needed to explore the longitudinal associations.

Measurement equivalence of the Four-Dimensional Symptom Questionnaire (4DSQ) in adolescents and emerging adults

The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report instrument measuring distress, depression, anxiety and somatization. The questionnaire has been developed and validated in adult samples. It is unknown whether adolescents and emerging adults respond to the 4DSQ items in the same way as adults do. The objective of the study was to examine measurement equivalence of the 4DSQ across adolescents, emerging adults and adults. 4DSQ data were collected in a primary care psychotherapy practice (N = 1349). Measurement equivalence was assessed using differential item and test functioning (DIF and DTF) analysis in an item response theory framework. DIF was compared across the following groups: adolescents (age 10–17), emerging adults (age 18–25), and adults (age 26–40). DIF was found in 9 items (out of 50) across adolescents and adults, and in 4 items across emerging adults and adults. The item with the largest DIF was ‘difficulty getting to sleep’, which was less severe for adolescents compared to adults. A likely explanation is that adolescents have a high base rate for problems with sleep initiation. The effect of DIF on the scale scores (DTF) was negligible. Adolescents and emerging adults score some 4DSQ items differently compared to adults but this had practically no effect on 4DSQ scale scores. 4DSQ scale scores from adolescents and emerging adults can be interpreted in the same way as 4DSQ scores from adults.

Searching for the optimal number of response alternatives for the distress scale of the four-dimensional symptom questionnaire

BACKGROUND

The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report questionnaire designed to measure distress, depression, anxiety, and somatization. Prior to computing scale scores from the item scores, the three highest response alternatives ('Regularly', 'Often', and 'Very often or constantly present') are usually collapsed into one category to reduce the influence of extreme responding on item- and scale scores. In this study, we evaluate the usefulness of this transformation for the distress scale based on a variety of criteria.

METHODS

Specifically, by using the Graded Response Model, we investigated the effect of this transformation on model fit, local measurement precision, and various indicators of the scale's validity to get an indication on whether the current practice of recoding should be advocated or not. In particular, the effect on the convergent- (operationalized by the General Health Questionnaire and the Maastricht Questionnaire), divergent- (operationalized by the Neuroticism scale of the NEO-FFI), and predictive validity (operationalized as obtrusion with daily chores and activities, the Biographical Problem list and the Utrecht Burnout Scale) of the distress scale was investigated.

RESULTS

Results indicate that recoding leads to (i) better model fit as indicated by lower mean probabilities of exact test statistics assessing item fit, (ii) small (<.02) losses in the sizes of various validity coefficients, and (iii) a decrease (DIFF (SE's) = .10-.25) in measurement precision for medium and high levels of distress.

CONCLUSIONS

For clinical applications and applications in longitudinal research, the current practice of recoding should be avoided because recoding decreases measurement precision for medium and high levels of distress. It would be interesting to see whether this advice also holds for the three other domains of the 4DSQ.

Cross-cultural validation of the German version of the Four-Dimensional Symptom Questionnaire (4DSQ) in multimorbid elderly people

PURPOSE

Psychosomatic symptoms and mental health problems are highly prevalent in multimorbid elderly people challenging general practitioners to differentiate between normal stress and psychopathological conditions. The 4DSQ is a Dutch questionnaire developed to detect anxiety, depression, somatization, and distress in primary care. This study aims to analyze measurement equivalence between a German version and the original Dutch instrument.

METHODS

A Dutch and a German sample of multimorbid elderly people, matched by gender and age, were analyzed. Equivalence of scale structures was assessed by confirmatory factor analysis (CFA). To evaluate measurement equivalence across languages, differential item functioning (DIF) was analyzed using Mantel-Haenszel method and hybrid ordinal logistic regression analysis. Differential test functioning (DTF) was assessed using Rasch analysis.

RESULTS

A total of 185 German and 185 Dutch participants completed the questionnaire. The CFA confirmed one-factor models for all scales of both 4DSQ versions. Nine items in three scales were flagged with DIF. The anxiety scale showed to be free of DIF. DTF analysis revealed negligible scale impact of DIF.

CONCLUSIONS

The German 4DSQ demonstrated measurement equivalence to the original Dutch instrument. Hence, it can be considered a valid questionnaire for the screening for mental health problems in primary care.

Insomnia Really Hurts: Effect of a Bad Night's Sleep on Pain Increases With Insomnia Severity

Insomnia and chronic pain are highly prevalent conditions and are often comorbid. Somatic complaints other than pain are also often observed in insomnia. Poor sleep and pain are known to mutually reinforce each other. However, it is unknown whether the habitual severity of insomnia modulates the acute effect of a particularly bad night's sleep on the next day's pain severity, and whether it modulates the acute effect of pain on the following night's sleep quality. Using data from 3,508 volunteers (2,684 female, mean age 50.09 y), we addressed these questions in addition to the associations between the habitual severity of insomnia, somatic complaints, and pain. Results indicated that people suffering from more severe habitual insomnia showed stronger mutual acute within-day reactivity of pain and poor sleep quality. The same increased reactivity was found in people with more severe habitual pain. Interestingly, the acute within-day mutual reactivity of pain and sleep quality showed consistent asymmetry. Pain worsened more after a particularly bad night's sleep than it improved after a particularly good night's sleep. Likewise, sleep worsened more after a day with more-than-usual pain than it improved after a day with less-than-usual pain. Future interventions may profit from addressing this asymmetric mutual reactivity especially in people with severe comorbid insomnia and chronic pain.

Improved health-related quality of life, participation, and autonomy in patients with treatment-resistant chronic pain after an intensive social cognitive intervention with the participation of support partners

Despite the availability of various specific treatments, most patients with chronic pain (CP) consider their pain problem as undertreated. Recently, multiple sclerosis (MS) patients who were given an intensive 3-day social cognitive treatment with the participation of support partners experienced lasting improvements in health-related quality of life (HRQoL) and self-efficacy. In this study, a similar intervention was given to treatment-resistant CP patients with stressors, relational problems with support partner, and distress, anxiety or depression. Before and 1, 3, and 6 months after the intervention, patients completed the Euro-Qol 5 Dimensions 5 Levels (EQ-5D-5L) and Impact on Participation and Autonomy (IPA) questionnaires (primary outcomes), and the Survey Of Pain Attitudes (SOPA), the Four-Dimensional Symptom Questionnaire (4DSQ) (distress, depression, anxiety, and somatization), and Visual Analog Scale for pain intensity, whereas the support partners completed the Caregiver Strain Index (CSI) questionnaire. Differences between baseline and post-treatment were tested via paired t-tests (significance level 0.05). Of the 39 patients who were included, 34 (87.2%) completed the 3-day treatment. At 1, 3, and 6 months, improvements were seen in EQ-5D-5L-Index (+40.6%; +22.4%; +31.7%), Health Today (+61.8%; +36.3%; +46.8%), Control attitude (+45.8%; not significant [NS]; +55.0%) and decreases in IPA-Problems (−14.8%; NS; −20.4%), Harm attitude (−18.9%; −15.0%; −17.7%), Distress (−17.7%; −31.8%; −37.1%), and Depression (−37.4%; −31.4%; −35.7%) scores. The CSI score had decreased by −29.0%, −21.4%, and −25.9%, respectively. In conclusion, after an intensive 3-day social cognitive intervention, treatment-resistant CP patients experienced substantial and lasting improvements in HRQoL and in problematic limitations to participation and autonomy, in association with improvements in pain attitudes, depression, and distress. To assess whether this innovative approach may be an effective treatment for this subgroup of CP patients, future randomized controlled studies are needed.

Identifying levels of general distress in first line mental health services: can GP- and eHealth clients' scores be meaningfully compared?

BACKGROUND

The Four-Dimensional Symptom Questionnaire (4DSQ) (Huisarts Wetenschap 39: 538-47, 1996) is a self-report questionnaire developed in the Netherlands to distinguish non-specific general distress from depression, anxiety, and somatization. This questionnaire is often used in different populations and settings and there is a paper-and-pencil and computerized version.

METHODS

We used item response theory to investigate whether the 4DSQ measures the same construct (structural equivalence) in the same way (scalar equivalence) in two samples comprised of primary mental health care attendees: (i) clients who visited their General Practitioner responded to the 4DSQ paper-and-pencil version, and (ii) eHealth clients responded to the 4DSQ computerized version. Specifically, we investigated whether the distress items functioned differently in eHealth clients compared to General Practitioners' clients and whether these differences lead to substantial differences at scale level.

RESULTS

Results showed that in general structural equivalence holds for the distress scale. This means that the distress scale measures the same construct in both General Practitioners' clients and eHealth clients. Furthermore, although eHealth clients have higher observed distress scores than General Practitioners' clients, application of a multiple group generalized partial credit response model suggests that scalar equivalence holds.

CONCLUSIONS

The same cutoff scores can be used for classifying respondents as having low, moderate and high levels of distress in both settings.