Measuring maternal mental health using the Dutch Four-Dimensional Symptom Questionnaire (4DSQ): Pregnancy-related item bias across the perinatal period.

OBJECTIVE: the Four-Dimensional Symptom Questionnaire (4DSQ) measures four dimensions of common psychopathology: distress, depression, anxiety and somatization. The instrument is developed and validated for general practice. A previous validation study of the 4DSQ for midwifery practice indicated that pregnant women respond differently to the items of the 4DSQ. This phenomenon is called item bias. The present study is a followup validation study in which pregnant women were followed up until one year post partum, to assess pregnancy-related item bias. DESIGN: cohort study with repeated measurements. SETTING AND PARTICIPANTS: the research group consisted of participants of the Mom@Work study, a study concerning mental health in a group of 574 working pregnant women and young mothers, recruited between 2004 and 2006. Measurements in the research group took place at 33 weeks of pregnancy and post partum at 7, 13, 25 and 52 weeks. The comparison group consisted of female general practice patients, matched for age (N=835). MEASUREMENTS AND FINDINGS: pregnancy-related item bias was assessed by two methods of differential item functioning (DIF) analysis: ordinal logistic regression (OLR) and the Mantel-Haenszel (MH) method. The impact of item bias on total scale scores was estimated by linear regression. Impact of item bias was found in the somatization-, distress- and anxiety scales of the 4DSQ across the perinatal period up until 13 weeks post partum. The depression scale remained free of item bias. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: pregnant and postpartum women responded differently to the 4DSQ than the women in the comparison group up until 13 weeks post partum. Pregnancy-related item bias lead to overestimation of distress and underestimation of somatization and anxiety. The depression scale was free of bias. The 4DSQ is a valid tool for case-finding and assessment of psychological conditions in the perinatal period, provided cut-off points are adapted up until 13 weeks post partum. Validation of generic questionnaires is recommended before using them in the perinatal period.

Distinguishing between emotional distress and psychiatric disorder in primary care attenders: A cross sectional study of the four-dimensional symptom questionnaire (4DSQ).

BACKGROUND: Detection of psychiatric disorder in primary care is a complex issue. Distinctions between 'normal' emotional distress and psychiatric disorder depend on how disorder is conceptualized. Our aim was to explore two different conceptualizations by examining patients' scores on one-dimensional depression measures and scores on the Four Dimensional Symptom Questionnaire (4DSQ), a measure that uniquely has separate dimensions for general distress and depressive disorder. METHODS: This was a cross sectional study of 487 primary care patients attending general clinics in Hampshire, UK. Patients completed the 4DSQ, Patient Health Questionnaire-9 (PHQ-9), General Health Questionnaire-12 (GHQ-12) and the Hospital Anxiety and Depression Scale (HADS) whilst in the waiting room. RESULTS: The 4DSQ classified 26% (126/485) of patients as having heightened distress levels and 8% (38/468) as possible cases of depressive disorder. Casesness was consistently higher across the one-dimensional measures (PHQ-9: 16%, GHQ-12: 28%, HADS-D: 13%). Of those patients deemed possible cases by the PHQ-9 (≥ 10), the 4DSQ classified 91% (71/78) as having heightened distress and 44% (32/72) as possible cases of depressive disorder. LIMITATIONS: The sample was predominately older and white, which may limit generalizability of the findings to more diverse patient groups. There are limits to self-report measures in the assessment of complex diagnostic issues. CONCLUSIONS: Inclusion of a distinct general distress dimension alongside a dimension focusing on specific depression symptomatology lowered the number of primary care patients classified as possible cases of disorder. This view of symptoms may have implications for the targeting of existing treatments, and may be useful in guiding the development of novel self-management interventions.

Minimal important change (MIC) based on a predictive modeling approach was more precise than MIC based on ROC analysis.

OBJECTIVES: To present a new method to estimate a "minimal important change" (MIC) of health-related quality of life (HRQOL) scales, based on predictive modeling, and to compare its performance with the MIC based on receiver operating characteristic (ROC) analysis. To illustrate how the new method deals with variables that modify the MIC across subgroups. STUDY DESIGN AND SETTING: The new method uses logistic regression analysis and identifies the change score associated with a likelihood ratio of 1 as the MIC. Simulation studies were conducted to investigate under which distributional circumstances both methods produce concordant or discordant results and whether the methods differ in accuracy and precision. RESULTS: The "predictive MIC" and the ROC-based MIC were identical when the variances of the change scores in the improved and not-improved groups were equal and the distributions were normal or oppositely skewed. The predictive MIC turned out to be more precise than the ROC-based MIC. The predictive MIC allowed for the testing and estimation of modifying factors such as baseline severity. CONCLUSION: In many situations, the newly described MIC based on predictive modeling yields the same value as the ROC-based MIC but with significantly greater precision. This advantage translates to increased statistical power in MIC studies.

Systematic tailoring for the implementation of guideline recommendations for anxiety and depressive disorders in general practice: perceived usefulness of tailored interventions.

BACKGROUND: The uptake of guideline recommendations in general practice can potentially be improved by designing implementation interventions that are tailored to prospectively identify barriers. However, there is insufficient evidence regarding the most effective and efficient approaches to tailoring. Our study provides an insight into the usefulness of tailored interventions to prospectively identified barriers affecting the uptake of guideline recommendations for anxiety and depressive disorders experienced by general practitioners (GPs) in their local context. METHODS: A qualitative study was conducted, in which 23 GPs gave informed consent and 14 finally participated. To explore the barriers affecting the uptake of guideline recommendations, a face-to-face interview was conducted with each GP to generate a personalised list. In response to this list, interventions were tailored to remove the barriers experienced by the GPs. To examine the perceived usefulness of the tailored interventions, telephone interviews were conducted after one year and coded through thematic coding. The analysis was descriptive in nature. RESULTS: The most frequently perceived barriers were: a lack of knowledge and skills, no agreement on guideline recommendations, negative outcome expectancy, low self-efficacy, no consensus with patients, and a lack of information about treatments provided by mental health professionals, together with waiting lists. The tailored interventions 'peer group supervision' and 'individualised telephone consultations' were perceived as useful by most GPs. Besides the tailored interventions, a perceived benefit of using a self-rating scale, measuring depressive and anxiety symptoms, and the idea of delivering better patient care, were supportive in the uptake of guideline recommendations. CONCLUSIONS: Our findings suggest that tailoring interventions to prospectively identified barriers, affecting the uptake of guideline recommendations for anxiety and depressive disorders, as perceived by GPs, may enhance the implementation of these guideline recommendations.

Integrating nurse-led Self-Management Support (SMS) in routine primary care: design of a hybrid effectiveness-implementation study among type 2 diabetes patients with problems of daily functioning and emotional distress: a study protocol.

BACKGROUND: Psychosocial problems are more prevalent among patients with chronic diseases than among the general population. They may lead to a downward spiral of poor adherence, deterioration of the condition and decline in daily functioning. In addition to medical management, systematic attention to emotional and role management tasks during routine chronic care seems mandatory. We intend to integrate an existing nurse-led minimal psychological intervention to support patients' self-management, which appeared to be effective and cost-effective, in routine care by primary care nurses, so we adjusted it to fit the host setting. The resulting Self-Management Support (SMS) programme involves early detection of patients with emotional distress and problems of daily functioning, as well as self-management support through problem solving and reattribution techniques. Strategies to embed SMS in daily practice include training and booster sessions for practice nurses as well as organisational and financial arrangements. This study aims to simultaneously evaluate the implementation process and effects of SMS in routine care, using a hybrid effectiveness-implementation design. METHODS/DESIGN: Registration data, questionnaires and interviews will be used to explore the facilitators, barriers and costs regarding successful implementation of SMS. The effects of SMS will be evaluated in a pragmatic cluster-randomised controlled trial with a baseline measurement and follow-up measurements after 4 and 12 months. The population will consist of 46 practice nurses and their type 2 diabetes patients (N = 460; 10 per practice nurse). The practice nurses will be randomly assigned to the intervention or control group. Practice nurses of the intervention group will receive SMS training. Patients for the intervention and control groups will be recruited by a researcher-led self-administered screening procedure to decide which patients of those scheduled for routine consultation are likely to be detected by the practice nurses as eligible for the self-management support. Primary outcome measure is patients' daily functioning. Secondary measures include emotional well-being, participation, autonomy and control over the disease. DISCUSSION: Our hybrid study design is complicated by the detection method used by the practice nurses. This method is an implementation issue in itself that has consequences for the realisation and power of the effect evaluation. TRIAL REGISTRATION: Current Controlled Trials, NTR2764.

A validation study of the Four-Dimensional Symptom Questionnaire (4DSQ) in insurance medicine.

OBJECTIVE: This study aimed to evaluate the criterion validity and the diagnostic accuracy of the Four-Dimensional Symptom Questionnaire (4DSQ) regarding the identification of depressive and anxiety disorders in an insurance medicine setting. PARTICIPANTS: Our sample consisted of 230 individuals who applied for a work disability benefit due to mental health problems. METHODS: Depressive and anxiety disorders were assessed using the 4DSQ and the Composite International Diagnostic Interview (CIDI). Internal consistency was determined by calculating Cronbach's alpha values. Criterion validity was evaluated by regression techniques. A Receiver Operating Characteristic (ROC) analysis was performed to evaluate diagnostic accuracy. RESULTS: Of the 230 participants 109 (47.4%) had a current DSM-IV depressive disorder and 146 (63.5%) an anxiety disorder. The 4DSQ scales showed an excellent internal consistency. The depression scale of the 4DSQ had specific sensitivity for major depressive disorder. The anxiety scale was also sensitive for the anxiety disorders. The area under the ROC curve (AUC) indicated good diagnostic accuracy of the 4DSQ for assessing depressive and/or anxiety disorders: AUC-value 0.81 for both depression and anxiety. CONCLUSIONS: Although the 4DSQ shows good criterion validity and diagnostic accuracy with respect to depressive and anxiety disorders in applicants for a work disability benefit due to mental health problems, the feasibility of the 4DSQ as a screening measure for depressive and anxiety disorders is limited due to the high prevalence of depressive and anxiety disorders.

Cost-effectiveness of a minimal intervention for stress-related sick leave in general practice: results of an economic evaluation alongside a pragmatic randomised control trial.

BACKGROUND: Stress-related mental health problems negatively impact quality of life and productivity. Worldwide, treatment is often sought in primary care. Our objective was to determine whether a general practitioner-based minimal intervention for workers with stress-related sick leave (MISS) was cost-effective compared to usual care (UC). METHODS: We conducted an economic evaluation from a societal perspective. Quality-adjusted life years (QALYs) and resource use were measured by the EuroQol and cost diaries, respectively. Uncertainty was estimated by 95% confidence intervals, cost-effectiveness planes and acceptability curves. Sensitivity analyses and ancillary analyses based on preplanned subgroups were performed. RESULTS: No statistically significant differences in costs or QALYs were observed. The mean incremental cost per QALY was -euro 7356 and located in the southeast quadrant of the cost-effectiveness plane, whereby the intervention was slightly more effective and less costly. For willingness-to-pay (lambda) thresholds from euro 0 to euro 100,000, the probability of MISS being cost-effective was 0.58-0.90. For the preplanned subgroup of patients diagnosed with stress-related mental disorders, the incremental ratio was -euro 28,278, again in the southeast quadrant. Corresponding probabilities were 0.92 or greater. LIMITATIONS: Non-significant findings may be related to poor implementation of the MISS intervention and low power. Also, work-presenteeism and unpaid labor were not measured. CONCLUSIONS: The minimal intervention was not cost-effective compared to usual care for a heterogeneous patient population. Therefore, we do not recommend widespread implementation. However, the intervention may be cost-effective for the subgroup stress-related mental disorders. This finding should be confirmed before implementation for this subgroup is considered.

Cost-effectiveness of usual general practitioner care with or without antidepressant medication for patients with minor or mild-major depression.

BACKGROUND: Minor depression is common in primary care and associated with increased health care costs. Many mildly depressed patients are prescribed antidepressants, although there is insufficient information on the cost-effectiveness of antidepressants for these patients. The objective of this study was to evaluate whether usual care without antidepressants is equivalent to (i.e. as effective as and as expensive as) usual care with antidepressants in patients with minor or mild-major depression. METHODS: Severity of depression was measured using the Montgomery Asberg Depression Rating Scale (MADRS) and quality-adjusted life-years (QALYs) using the EuroQol. Resource use was measured from a societal perspective using cost diaries. Bootstrapping was used to analyze the cost-effectiveness data. RESULTS: Equivalence could not be shown for improvement in MADRS score or QALYs gained at 52 weeks. The mean (95% CI) difference in total costs between usual care without antidepressants and usual care with antidepressants was -euro751 (-3601; 1522). Using an equivalence margin of euro500 equivalence in costs could not be shown. In the cost-effectiveness analyses equivalence also could not be shown. LIMITATIONS: This study was underpowered for economic outcomes. Another limitation was the loss-to-follow-up. CONCLUSIONS: Although equivalence could not be shown in the costs and cost-effectiveness analyses, 95% confidence intervals also did not show that usual care without antidepressants was vastly superior or inferior to usual care with antidepressants. Therefore, we recommend general practitioners to show restraint when prescribing antidepressants to mildly depressed patients.

Cost-effectiveness of a workplace intervention for sick-listed employees with common mental disorders: design of a randomized controlled trial.

BACKGROUND: Considering the high costs of sick leave and the consequences of sick leave for employees, an early return-to-work of employees with mental disorders is very important. Therefore, a workplace intervention is developed based on a successful return-to-work intervention for employees with low back pain. The objective of this paper is to present the design of a randomized controlled trial evaluating the cost-effectiveness of the workplace intervention compared with usual care for sick-listed employees with common mental disorders. METHODS: The study is designed as a randomized controlled trial with a follow-up of one year. Employees eligible for this study are on sick leave for 2 to 8 weeks with common mental disorders. The workplace intervention will be compared with usual care. The workplace intervention is a stepwise approach that aims to reach consensus about a return-to-work plan by active participation and strong commitment of both the sick-listed employee and the supervisor. Outcomes will be assessed at baseline, 3, 6, 9 and 12 months. The primary outcome of this study is lasting return-to-work, which will be acquired from continuous registration systems of the companies after the follow-up. Secondary outcomes are total number of days of sick leave during the follow-up, severity of common mental disorders, coping style, job content, and attitude, social influence, and self-efficacy determinants. Cost-effectiveness will be evaluated from the societal perspective. A process evaluation will also be conducted. DISCUSSION: Return-to-work is difficult to discuss in the workplace for sick-listed employees with mental disorders and their supervisors. Therefore, this intervention offers a unique opportunity for the sick-listed employee and the supervisor to discuss barriers for return-to-work. Results of this study will possibly contribute to improvement of disability management for sick-listed employees with common mental disorders. Results will become available in 2009. TRIAL REGISTRATION: ISRCTN92307123.

Cost-effectiveness of an activating intervention by social workers for patients with minor mental disorders on sick leave: a randomized controlled trial.

BACKGROUND: Sickness absence often occurs in patients with emotional distress or minor mental disorders. In several European countries, these patients are over-represented among those receiving illness benefits, and interventions are needed. The aim of this study was to evaluate the cost-effectiveness of an intervention conducted by social workers, designed to reduce sick leave duration in patients absent from work owing to emotional distress or minor mental disorders. METHODS: In this Randomized Controlled Trial, patients were recruited by GPs. The intervention group (N = 98) received an activating, structured treatment by social workers, the control group (N = 96) received routine GP care. Sick leave duration, clinical symptoms, and medical consumption (consumption of medical staffs' time as well as consumption of drugs) were measured at baseline and 3, 6, and 18 months later. RESULTS: Neither for sick leave duration nor for clinical improvement over time were significant differences found between the groups. Also the associated costs were not significantly lower in the intervention group. CONCLUSIONS: Compared with usual GP care, the activating social work intervention was not superior in reducing sick leave duration, improving clinical symptoms, and decreasing medical consumption. It was also not cost-effective compared with GP routine care in the treatment of minor mental disorders. Therefore, further implementation of the intervention is not justified. Potentially, programmes aimed at reducing sick leave duration in patients with minor mental disorders carried out closer to the workplace (e.g. by occupational physicians) are more successful than programmes in primary care.

Reliability and validity of the assessment of depression in general practice: the Short Depression Interview (SDI).

General practitioners (GPs) are recommended to use DSM-IV criteria to diagnose major depression in daily clinical practice. This implies the assessment of nine depressive symptoms and four additional criteria. A short structured interview has been developed to assess these symptoms and criteria, and a study was carried out to investigate the reliability and validity with which GPs can assess these symptoms and criteria and the DSM-IV diagnosis of major depression. In 14 general practices, 52 patients with symptoms of distress and depression were interviewed twice by their GP, with an interval of one to four days. Furthermore, the patients filled out three depression questionnaires. The reproducibility of eight symptoms and three additional criteria was moderate to good (kappa >0.40). The reproducibility of the depressive symptom count, that is necessary to arrive at a diagnosis of major depression, was such that in 75 percent of the patients the test-retest difference did not exceed one symptom. The reproducibility of the diagnosis of major depression was good (kappa 0.63). The validity of the diagnosis of major depression assessed by the GPs, as compared to results of the self-report depression questionnaires, was satisfactory (r 0.35-0.61). Diagnosing major depression in patients with depressive symptomatology just above or below the threshold of major depression warrants a certain amount of caution in general practice.