Psychometric validation of the Danish version of the Major Depression Inventory using data from the Lolland-Falster health study (LOFUS).

PURPOSE: The Major Depression Inventory (MDI) is a widely used self-rating depression scale commonly in primary care in Denmark. It has not been subject to robust psychometric validation in a general population setting. The aim of this study was to evaluate the psychometric measurement properties of the MDI when applied in the general population. METHODS: We evaluated statistical psychometric validity using modern test theory (confirmatory factor analysis, item response theory models and Rasch measurement theory) testing local independence and differential item function across groups defined by gender, age, education, and chronic disease status. Separate analyses across different strata and across different statistical models were employed. RESULTS: Regarding structural validity we consistently identified local dependence for the item two pairs (MDI2,MDI3) and (MDI4,MDI5) across strata. This result was confirmed by bifactor CFA models and item screening. We further identified substantial differential item functioning with respect to age group and with respect to chronic disease. We identified quantified the magnitude of this lack of measurement invariance. CONCLUSION: The MDI is psychometrically valid in homogenous sub populations, but the disclosed evidence of local dependence means that published estimates of its reliability cannot be trusted. The lack of measurement invariance means that the instrument cannot be used to compare individuals or groups unless they are similar in terms of age group and chronic disease status.

Concurrent validity of the anxiety symptom-scale compared to two well-being scales: results from the Lolland-Falster health study.

OBJECTIVE: To examine the concurrent validity of the Anxiety Symptom-scale against two well-being scales, the Cantril Ladder (CL) and World Health Organization Well-Being Index (WHO-5), to test the algorithm defining anxiety against these scales, and identify cut-off points for the Anxiety Symptom-scale sum score. SUBJECTS: 14,405 adult respondents completing all psychometric questions in the Lolland Falster Health Study. METHOD: Receiver operating characteristic analyses comparing Anxiety Symptom-scale WHO-5 and CL. RESULTS: 2.5% of respondents had an anxiety disorder (3% female and 2% male) according to the Anxiety Symptom-scale algorithm. The area under the curve (AUC) was 0.87 for CL and 0.90 for WHO-5 (using inverse scores), indicating high concordance with anxiety disorder as identified by the scale. A score solely ≥2 on item 10 is a relevant cut off to low wellbeing. Anxiety disorder covers a broad range on the scale's sum score, with 3 to 4 indicating low well-being in this population sample and a sensitivity of 0.85 - 0.99 against CL and WHO-5. CONCLUSION: The Anxiety Symptom-scale is a sensitive and valid instrument for the identification of patients in low well-being with symptoms of anxiety. A score ≥2 on the functional impact (Item 10) of all symptoms is a relevant indicator of anxiety associated with low well-being in this sample. A higher Anxiety Symptom-scale sum score is coherent with lower well-being, though without specific cut-off points. Further validation of the Anxiety Symptom-scale in a clinical setting is recommended.

Prevalence of anxiety disorders and association to socioeconomic position. Results from the Lolland Falster Health Study.

PURPOSE: The purpose of this study is to describe the prevalence of anxiety disorders in a general population and the association to socioeconomic position (SEP), which has not been described in a Danish context before. MATERIAL AND METHODS: We present data on anxiety symptoms from respondents in the rural-provincial Lolland-Falster population Health Study (LOFUS). Analyses of the questionnaire responses to the Anxiety Symptom Scale were done by descriptive statistics and logistic regression analyses adjusted for sex and age. RESULTS: 14,834 LOFUS respondents who completed the Anxiety Symptom Scale were included; According to the original algorithm 371 (2.5%) had an anxiety disorder. The adjusted odds ratios (aOR) for anxiety disorder were strongly associated to SEP. We found aOR for anxiety to be: 3.8 (confidence interval (CI 95%) 2.54 - 5.92) for respondents with no postsecondary education compared to those with 3+ years of postsecondary education; 11.9 (CI 8.89 - 16.01) for respondents temporarily out of a job compared to those working; 9.4 (CI 6.06 - 14.51) for those experiencing constant financial strain compared to those not experiencing financial strain. Relaxing the criteria for anxiety to item 10 > 1, the prevalence raised to 3.9%. The association was unchanged related to education; however, the aOR dropped to 9 and 8 respectively, for being temporally out of job, or in financial strain every month- when doing same comparisons. CONCLUSIONS: The 14-day prevalence of anxiety disorder seems low but strongly associated to SEP especially for individuals temporarily out of a job or experiencing financial strain.

Rasch analysis of the structural validity of the anxiety symptom scale in the lolland-falster health study.

BACKGROUND: We aimed to assess the psychometric properties of the ten-item Anxiety Symptom Scale (ASS) using Rasch analysis. Data from the Lolland-Falster Health Study (LOFUS) were used including ASS data for 16,137 persons aged 18-90 years. METHODS: Fit to the Rasch model, ordering of response categories, dimensionality testing, test for differential item functioning, test for local dependency of items, and calculation of reliability were used to evaluate the psychometric characteristics of the ASS. RESULTS: Ordered response categories were achieved for nine of ten items after modifying the original six-point scoring system into a five-point system. After adjustment of the sample size to 500 persons, the ASS fitted the Rasch Model (p = 0.051). Dimensionality testing supported combining the ten items into a total score. No significant differential item functioning was observed for sex, age group, and educational level. Items 1 and 9 and items 4 and 5 demonstrated indication of local dependency. Combining these two item pairs improved the fit of the ASS to the Rasch model. LIMITATIONS: The total ASS was poorly targeted for the LOFUS population as the majority of persons were located at the lower end of the construct. This poor alignment could explain the low reliability (PSI 0.49). Analyzing a balanced random sample of responders with high and low ASS scores demonstrated a sufficient PSI (0.81). CONCLUSIONS: Despite problems with the measurement structure, the ASS seems to be a promising instrument for measuring anxiety. However, it may prove more reliable for use in clinical samples of respondents.

Treatment of difficult-to-treat depression - clinical guideline for selected interventions.

BACKGROUND: Difficult-to-treat-depression (DTD) is a clinical challenge. The interventions that are well-established for DTD are not suitable or effective for all the patients. Therefore, more treatment options are highly warranted. We formulated an evidence-based guideline concerning six interventions not well-established for DTD in Denmark. METHODS: Selected review questions were formulated according to the PICO principle with specific definitions of the patient population (P), the intervention (I), the comparison (C), and the outcomes of interest (O), and systematic literature searches were performed stepwise for each review question to identify relevant systematic reviews/meta-analyses, and randomized controlled trials. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the methodological quality of the included studies. Clinical recommendations were formulated based on the evidence, the risk-benefit ratio, and perceived patient preferences. RESULTS: We found sufficient evidence for a weak recommendation of repetitive transcranial magnetic stimulation (rTMS) and cognitive behavioural analysis system of psychotherapy (CBASP). The use of bright light therapy in DTD was not sufficiently supported by the evidence, but should be considered as good clinical practice. The interventions should be considered in addition to ongoing antidepressant treatment. We did not find sufficient evidence to recommend intravenous ketamine/esketamine, rumination-focused psychotherapy, or cognitive remediation to patients with DTD. CONCLUSION: The evidence supported two of the six reviewed interventions, however it was generally weak which emphasizes the need for more good quality studies. This guideline does not cover all treatment options and should be regarded as a supplement to relevant DTD-guidelines.

Association of Socioeconomic Status With Dementia Diagnosis Among Older Adults in Denmark.

Importance: Low socioeconomic status (SES) has been identified as a risk factor for the development of dementia. However, few studies have focused on the association between SES and dementia diagnostic evaluation on a population level. Objective: To investigate whether household income (HHI) is associated with dementia diagnosis and cognitive severity at the time of diagnosis. Design, Setting, and Participants: This population- and register-based cross-sectional study analyzed health, social, and economic data obtained from various Danish national registers. The study population comprised individuals who received a first-time referral for a diagnostic evaluation for dementia to the secondary health care sector of Denmark between January 1, 2017, and December 17, 2018. Dementia-related health data were retrieved from the Danish Quality Database for Dementia. Data analysis was conducted from October 2019 to December 2020. Exposures: Annual HHI (used as a proxy for SES) for 2015 and 2016 was obtained from Statistics Denmark and categorized into upper, middle, and lower tertiles within 5-year interval age groups. Main Outcomes and Measures: Dementia diagnoses (Alzheimer disease, vascular dementia, mixed dementia, dementia with Lewy bodies, Parkinson disease dementia, or other) and cognitive stages at diagnosis (cognitively intact; mild cognitive impairment but not dementia; or mild, moderate, or severe dementia) were retrieved from the database. Univariable and multivariable logistic and linear regressions adjusted for age group, sex, region of residence, household type, period (2017 and 2018), medication type, and medical conditions were analyzed for a possible association between HHI and receipt of dementia diagnosis. Results: Among the 10 191 individuals (mean [SD] age, 75 [10] years; 5476 women [53.7%]) included in the study, 8844 (86.8%) were diagnosed with dementia. Individuals with HHI in the upper tertile compared with those with lower-tertile HHI were less likely to receive a dementia diagnosis after referral (odds ratio, 0.65; 95% CI, 0.55-0.78) and, if diagnosed with dementia, had less severe cognitive stage (ß, -0.16; 95% CI, -0.21 to -0.10). Individuals with middle-tertile HHI did not significantly differ from those with lower-tertile HHI in terms of dementia diagnosis (odds ratio, 0.92; 95% CI, 0.77-1.09) and cognitive stage at diagnosis (ß, 0.01; 95% CI, -0.04 to 0.06). Conclusions and Relevance: The results of this study revealed a social inequality in dementia diagnostic evaluation: in Denmark, people with higher income seem to receive an earlier diagnosis. Public health strategies should target people with lower SES for earlier dementia detection and intervention.

Socioeconomic position and mental health care use before and after first redeemed antidepressant and time until subsequent contact to psychologist or psychiatrists: a nationwide Danish follow-up study.

PURPOSE: The purpose was to investigate inequalities in access to care among people with possible depression. METHOD: In this nationwide register-based cohort study of 30,593 persons, we observed the association between socioeconomic position (SEP, education/income) and mental health care use (MHCU) four months before the date of first redeemed antidepressant (Index Date/ID) and 12 months afterwards-and time to contact to psychologist/psychiatrist (PP). Logistic, Poisson, and Cox regression models were used, adjusted for sex, age, cohabitation, and psychiatric comorbidity. RESULTS: Before ID, high SEP was associated with less GP contact (general practitioner), higher odds ratios for GP-Mental Health Counseling (GP-MHC), psychologist contact, and admissions to hospital. This disparity decreased the following 12 months for GP-MHC but increased for contact to psychologist; same pattern was seen for rate of visits. However, the low-income group had more contact to private psychiatrist. For the 25,217 individuals with no MHCU before ID, higher educational level was associated with almost twice the rate of contact to PP the following 12 months; for the high-income group, the rate was 40% higher. 10% had contact to PP within 40 days after ID in the group with higher education; whereas, 10% of those with a short education would reach PP by day 120. High-income group had faster access as well. CONCLUSION: Being in high SEP was positively associated with MHCU, before and after ID, and more rapid PP contact, most explicit when measured by education. Co-payment for psychologist may divert care towards private psychiatrist for low-income groups.

Questionnaire development for the Lolland-Falster Health Study, Denmark: an iterative and incremental process.

In composing multi-thematic questionnaires for the Lolland-Falster Health Study (LOFUS), we faced a range of challenges, for which we found limited guidance in the literature. LOFUS is a household-based population study covering multiple medical and social research areas and targeting the mixed rural-provincial population of 103,000 persons on the Danish islands Lolland and Falster. Households were randomly selected for invitation. In this paper, we describe and discuss challenges in developing the questionnaires related to stakeholders, content of the questionnaire, and the process itself. The development process was characterised by loops of learning and can be described as an iterative and incremental process. We propose recommendations to researchers and administrators involved in similar development processes, including awareness of the non-linearity and complexity of the process, a need for negotiations and navigation among multiple stakeholders, and acknowledgement of pragmatism as an inherent part of decisions made in the process.

Are perceived barriers to accessing mental healthcare associated with socioeconomic position among individuals with symptoms of depression? Questionnaire-results from the Lolland-Falster Health Study, a rural Danish population study.

OBJECTIVE: To evaluate if perceived barriers to accessing mental healthcare (MHC) among individuals with symptoms of depression are associated with their socio-economic position (SEP). DESIGN: Cross-sectional questionnaire-based population survey from the Lolland-Falster Health Study (LOFUS) 2016-17 of 5076 participants. PARTICIPANTS: The study included 372 individuals, with positive scores for depression according to the Major Depression Inventory (MDI), participating in LOFUS . INTERVENTIONS: A set of five questions on perceived barriers to accessing professional care for mental health problem was posed to individuals with symptoms of depression (MDI score >20). OUTCOMES: The association between SEP (as measured by educational attainment, employment status and financial strain) and five different types of barriers to accessing MHC were analysed in separate multivariable logistic regression models adjusted for gender and age. RESULTS: A total of 314 out of 372 (84%) completed the survey questions and reported experiencing barriers to MHC access. Worry about expenses related to seeking or continuing MHC was a considerable barrier for 30% of the individuals responding and, as such, the greatest problem among the five types of barriers. 22% perceived Stigma as a barrier to accessing MHC, but there was no association between perceived Stigma and SEP. Transportation was not only the barrier of least concern for individuals in general but also the issue with the greatest and most consistent socio-economic disparity (OR 2.99, 95% CI 1.19 to 7.52) for the lowest vs highest educational groups and, likewise, concerning Expenses (OR 2.77, 95% CI 1.34 to 5.76) for the same groups. CONCLUSION: Issues associated with Expenses and Transport were more frequently perceived as barriers to accessing MHC for people in low SEP compared with people in high SEP. Stigma showed no association with SEP.Informed written consent was obtained. Region Zealand's Ethical Committee on Health Research (SJ-421) and the Danish Data Protection Agency (REG-24-2015) approved the study.

Socioeconomic position, symptoms of depression and subsequent mental healthcare treatment: a Danish register-based 6-month follow-up study on a population survey.

OBJECTIVE: Examine whether the severity of symptoms of depression was associated with the type of mental healthcare treatment (MHCT) received, independent of socioeconomic position (SEP). DESIGN: Register-based 6-month follow-up study on participants from the Danish General Suburban Population Study (GESUS) 2010-2013, who scored the Major Depression Inventory (MDI). PARTICIPANTS: Nineteen thousand and eleven respondents from GESUS. INTERVENTIONS: The MHCT of the participants was tracked in national registers 4 months prior and 6 months after their MDI scores. MHCT was graduated in levels. SEP was defined by years of formal postsecondary education and income categorised into three levels. Data were analysed using logistic and Poisson regression analyses. OUTCOMES: MHCT included number of contacts with: general practitioner (GP), GP mental health counselling, psychologist, psychiatrist, emergency contacts, admissions to psychiatric hospitals and prescriptions of antidepressants. RESULTS: For 547 respondents with moderate to severe symptoms of depression there was no difference across SEP in use of services, contact (y/n), frequency of contact or level of treatment, except respondents with low SEP had more frequent contact with their GP. However, of the 547 respondents , 10% had no treatment contacts at all, and 47% had no treatment beyond GP consultation. Among respondents with no/few symptoms of depression, postsecondary education ≥3 years was associated with more contact with specialised services (adjusted OR (aOR) 1.92; 95% CI 1.18 to 3.13); however, this difference did not apply for income; additionally, high SEP was associated with fewer prescriptions of antidepressants (education aOR 0.69; CI 0.50 to 0.95; income aOR 0.56, CI 0.39 to 0.80) compared with low SEP. CONCLUSION: Participants with symptoms of depression were treated according to the severity of their symptoms, independent of SEP; however, more than half with moderate to severe symptoms received no treatment beyond GP consultation. People in low SEP and no/few symptoms of depression were more often treated with antidepressants. The study was approved by The Danish Data Protection Agency Journal number 2015-41-3984. Accessible at: https://www.datatilsynet.dk/fortegnelsen/soeg-i-fortegnelsen/.

Correction to: Impact of socioeconomic position and distance on mental health care utilization: a nationwide Danish follow-up study.

In the original publication of this article, Table 3 was published incorrectly. The corrected table is shown below.

Impact of socioeconomic position and distance on mental health care utilization: a nationwide Danish follow-up study.

PURPOSE: To determine the impact of socioeconomic position (SEP) and distance to provider on outpatient mental health care utilization among incident users of antidepressants. METHOD: A nationwide register-based cohort study of 50,374 person-years. RESULTS: Persons in low SEP were more likely to have outpatient psychiatrist contacts [odds ratio (OR) 1.25; confidence interval (CI) 1.17-1.34], but less likely to consult a co-payed psychologist (OR 0.49; CI 0.46-0.53) and to get mental health service from a GP (MHS-GP) (OR 0.81; CI 0.77-0.86) compared to persons in high SEP after adjusting for socio-demographics, comorbidity and car ownership. Furthermore, persons in low SEP who had contact to any of these therapists tended to have lower rates of visits compared to those in high SEP. When distance to services increased by 5 km, the rate of visits to outpatient psychiatrist tended to decrease by 5% in the lowest income group (IRR 0.95; CI 0.94-0.95) and 1% in the highest (IRR 0.99; CI 0.99-1.00). Likewise, contact to psychologists decreased by 11% in the lowest income group (IRR 0.89; CI 0.85-0.94), whereas rate of visits did not interact. CONCLUSION: Patients in low SEP have relatively lower utilization of mental health services even when services are free at delivery; co-payment and distance to provider aggravate the disparities in utilization between patients in high SEP and patients in low SEP.