Measurement-based Treatment of Residual Symptoms Using Clinically Useful Depression Outcome Scale: Korean Validation Study

Measurement Properties of the Patient Health Questionnaire-15 and Somatic Symptom Scale-8: A Systematic Review and Meta-Analysis

Importance

The subjective experience of somatic symptoms is a key concern throughout the health care system. Valid and clinically useful instruments are needed.

Objective

To evaluate the measurement properties of 2 widespread patient-reported outcomes: the Patient Health Questionnaire-15 (PHQ-15) and Somatic Symptom Scale-8 (SSS-8).

Data Sources

Medline, PsycINFO, and Web of Science were last searched February 1, 2024.

Study Selection

English-language studies reporting estimates pertaining to factor analysis, taxometric analysis, internal consistency, construct validity, mean scores in relevant groups, cutoffs, areas under the receiver operating characteristic curves (AUROCs), minimal clinically important difference, test-retest reliability, or sensitivity to change.

Data Extraction and Synthesis

Search hits were reviewed by independent raters. Cronbach α, Pearson r, means, and between-group effect sizes indicative of sensitivity to change were pooled in random-effects meta-analysis. Study quality was assessed using 3 instruments. Reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 reporting guideline.

Main Outcomes and Measures

Comprehensive overview of evidence pertaining to the measurement properties of the PHQ-15 and SSS-8.

Results

A total of 305 studies with 361 243 participants were included. Most concerned routine care (178 studies) and the general population (27 studies). In factor analyses, both scales reflected a combination of domain-specific factors (cardiopulmonary, fatigue, gastrointestinal, pain) and a general symptom burden factor. The pooled PHQ-15 α was 0.81 (95% CI, 0.80-0.82), but with low item-total correlations for items concerning menstrual problems, fainting spells, and sexual problems (item-total correlations <0.40), and the SSS-8 α was 0.80 (0.77-0.83). Pooled correlations with other measures of somatic symptom burden were 0.71 (95% CI, 0.64-0.78) for the PHQ-15 and 0.82 (95% CI, 0.72-0.92) for the SSS-8. Reported AUROCs for identification of somatoform disorders ranged from 0.63 (95% CI, 0.50-0.76) to 0.79 (95% CI, 0.73-0.85) for the PHQ-15 and from 0.71 (95% CI, 0.66-0.77) to 0.73 (95% CI, 0.69-0.76) for the SSS-8. The minimal clinically important difference on both scales was 3 points. Test-retest reliability could not be pooled and was inconsistent for the PHQ-15 (PHQ-15: r = 0.65-0.93; ICC, 0.87; SSS-8: r = 0.996, ICC = 0.89). The PHQ-15 showed tentative sensitivity to change (g = 0.32; 95% CI, 0.08-0.56), but data for the SSS-8 were lacking.

Conclusions and Relevance

In this systematic review and meta-analysis, findings supported use of the PHQ-15 and SSS-8 for the assessment of symptom burden, but users should be aware of the complex, multifactorial structures of these scales. More evidence is needed concerning longitudinal measurement properties.

A psychometric analysis of the Japanese version of the clinically useful depression outcome scale supplemented with questions for the DSM-5 anxious distress specifier (CUDOS-A)

AIM

The aim of the study was to identify the clinical significance of anxiety in those with depression, the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) defined criteria for an anxious distress specifier for major depressive disorder (MDD). The Clinically Useful Depression Outcome Scale (CUDOS) supplemented with questions for the DSM-5 anxious distress specifier (CUDOS-A) is a self-report instrument to assess the clinical significance of anxiety in addition to assess symptoms and the severity of depression. This study aimed to evaluate the psychometric properties of the Japanese version of the CUDOS-A.

METHODS

An observational, prospective study was conducted with 131 MDD outpatients and 200 healthy controls. The Japanese version of the CUDOS-A, along with other measures, was administered to assess depressive symptoms, anxiety, social function, and biological rhythm. Reliability and validity analyses were performed, including internal consistency, test-retest reliability, convergent validity, and contrasted-groups validity.

RESULTS

The Japanese version of the CUDOS-A demonstrated excellent internal consistency (Cronbach's alpha = 0.96) and test-retest reliability (ICC = 0.78). Significant positive correlations were found between the CUDOS-A and measures of depression, anxiety, social function, and biological rhythm (all, p < 0.001), supporting its convergent validity. The CUDOS-A effectively differentiated between patients with MDD and healthy controls (p < 0.001), indicating good contrasted-groups validity.

CONCLUSIONS

The Japanese version of the CUDOS-A is a useful measure for research and for clinical practice, enabling the efficient assessment of anxious distress in individuals with depression.

Rasch analysis of the Chinese version of the clinically useful depression outcome scale in patients with major depressive disorder

OBJECTIVE

To examine the psychometric properties of the Chinese version of the Clinically Useful Depression Outcome Scale (CUDOS) in the Chinese patients with major depressive disorder (MDD) using Rasch analysis.

METHODS

The sample consisted of 283 patients with MDD (69% females). The Rasch model was applied to examine the overall fit of the Chinese version of CUDOS and the fit of the 18 items. Dimensionality, item-model fit, differential item functioning (DIF), reliability, ordering of response category and targeting were tested to examine the psychometric properties of the Chinese version of CUDOS.

RESULTS

Rasch analysis demonstrated the unidimensionality of the Chinese version of CUDOS. Of the 18 items, three items (item 4, item 5, item 6) showed misfit in the model. After merging item 4 into item 3 and item 6 into item 5, the overall model fit improved. The person separation index (PSI) was 3.0 and the person reliability coefficient was 0.90. No evidence of significant DIF was found when associated with gender and age. No disordered category and threshold of the rating response were observed, which meant the response category setting was reasonable. The mean ability of person was - 0.53.

CONCLUSION

The results suggested that the Chinese version of CUDOS has acceptable psychometric properties. In order to improve the quality and applicability of the Chinese version of CUDOS, the merging of item 4 into item 3 and item 6 into item 5 are suggested.

Comparison between Atomoxetine and OROS Methylphenidate as an Adjunctive to SSRIs in Attention-deficit/Hyperactivity Disorder Adults with Comorbid Partially Responsive Major Depressive Disorder: A Head-to-head, 12-week, Randomized, Rater-blinded Clinical Trial

Objective

This study aimed to compare the efficacy and safety of atomoxetine (ATX) and OROS methylphenidate (MPH) as adjunctive to selective serotonin reuptake inhibitors (SSRIs) in adults with attention-deficit hyperactivity disorder (ADHD) with comorbid partially responsive major depressive disorder (MDD).

Methods

Sixty Korean adults with ADHD and comorbid partially responsive MDD were recruited in a 12-week, randomized, rater-blinded, active-controlled trial and were evenly randomized to ATX or OROS MPH treatment.

Results

Depressive symptoms measured using the Hamilton Depression Rating Scale and Clinically Useful Depression Outcome Scale, and ADHD symptoms measured using the Adult ADHD Self-Report Scale, as well as the Clinical Global Impression-Severity, Clinical Global Impression-Improvement, and the Sheehan Disability Scale scores were significantly improved in both groups during the 12 weeks of treatment. The changes in all outcome measures during the 12-week treatment were not significantly different between the two groups (all p > 0.05). No serious adverse events were reported and there were no significant differences in systolic and diastolic blood pressure, pulse rate, weight, or body mass index between the ATX and MPH groups.

Conclusion

Our findings suggest that ATX and MPH can be used as adjunctive treatments in adults with ADHD and comorbid partially responsive MDD. The efficacy and tolerability of ATX and MPH in adults with ADHD did not differ significantly. Further studies should be conducted to draw a definitive conclusion.

Reliability and validity of clinically useful depression outcome scale identifying mixed features in patients with manic episode

OBJECTIVES

This study aims to explore the reliability, validity, and feasibility of Clinically Useful Depression Outcome Scale (CUDOS) in screening mixed features in patients diagnosed with mania.

METHODS

A total of 109 patients with (hypo-) manic episode were recruited. The reliability of Chinese version of CUDOS (CUDOS-C) were analyzed with Cronbach's alpha and intraclass correlation coefficient (ICC). Spearman correlation coefficient was used to analyze the validity by comparing the correlation between CUDOS-C and Patient Health Questionnaire-9 (PHQ-9), 32-item Hypomania Checklist (HCL-32). The score of MINI (hypo-) manic episode with mixed features-DSM-5 Module-Chinese version(MINI-M-C) ≥ 2 was considered as the gold standard of mixed features, and the receiver operating characteristic (ROC) curve analysis was used to calculate the optimal cut-off values of CUDOS-C score.

RESULTS

The Cronbach's alpha value of CUDOS-C was 0.898, and the ICC of CUDOS-C test-retest was 0.880 (95% CI: 0.812-0.923, p < .05).The CUDOS-C score was significantly correlated with PHQ-9 score (r = 0.893, p = .000), but not with HCL-32 score(r = 0.088, p = .364).The area under ROC curve was 0.909 (95% CI: 0.855 to 0.963, p < .001) for CUDOS-C identifying mixed features in mania. The optimal cut-off value was 11 with a sensitivity of 0.854 and a specificity of 0.868. The CUDOS-C (score ≥ 12) identified 40.4% of the patients with mixed features, which was higher than those diagnosed by clinicians (18.3%) and screened using MINI-M-C (37.6%).

CONCLUSIONS

The results indicate the CUDOS-C is a reliable and valid self-administered questionnaire for assessing depressive symptoms and screening patients with mixed mania.

Additional Reduction of Residual Symptoms with Aripiprazole Augmentation in the Patients with Partially Remitted Major Depressive Disorder

Objective

Many patients with major depressive disorder (MDD) suffer from residual symptoms without achieving remission. However, pharmacologic options for residual symptoms of MDD have been limited. This study aimed to investigate benefit of aripiprazole augmentation in the treatment of residual symptoms in the patients with partially remitted MDD.

Methods

We retrospectively analyzed the 8-week medical records of the patients. The enrolled patients did respond to treatment of antidepressant but were not remitted. The range of 17-item Hamilton Depression Rating Scale (HAMD) total score of the subjects were 8 to 15 points. All patients were currently taking antidepressants when they started aripiprazole. The primary endpoint was the mean change of Clinically Useful Depression Outcome Scale (CUDOS). Secondary endpoint measures were HAMD, Clinical Global Impression-severity (CGI-S) scores, Patient Health Questionnaire-15 (PHQ-15), Beck Anxiety Inventory (BAI), Perceived Deficit Questionnaire-depression (PDQ-D), Sheehan Disability Scale (SDS) and General Health Questionnaire/Quality of Life-12 (GHQ/QL-12).

Results

A total of 134 medical records were analyzed. The changes of CUDOS, HAMD, CGI-S, BAI, PHQ-15, PDQ-D, SDS and GHQ/QL-12 from baseline to the endpoint were −7.93, −3.29, −0.80, −4.02, −2.05, −4.35, −4.77 and −2.82, respectively (all p < 0.001). At the endpoint, the newly remitted subjects rate by HAMD score criteria were approximately 46%.

Conclusion

Our preliminary findings have presented the effectiveness of aripiprazole augmentation for residual symptoms of partially remitted MDD patients in routine practice. This study assures subsequent well-controlled studies of the possibility of generalizing the above promising outcome in the future.

Estructura interna y evidencias de validez de la Escala Baptista de Depresión para Adultos en población adulta de Argentina

El objetivo de este estudio fue analizar la estructura factorial de la adaptación al español rioplatense de la Escala Baptista de Depresión para Adultos (ebadep-a) en población argentina, y aportar evidencias de validez sobre la misma. Para evaluar la estructura interna de la escala se realizaron cálculos por medio de análisis factoriales exploratorios y confirmatorios, así como de la teoría de respuesta al ítem; mientras que, para brindar evidencias de validez convergente y concurrente, se aplicaron correlaciones, regresiones y análisis de modelos de ecuaciones estructurales (SEM) con medidas relacionadas. Los resultados sugieren que la versión final del instrumento podría reducirse de 45 a 23 ítems con adecuados índices de ajuste, con un modelo unidimensional, y con cargas factoriales satisfactorias tanto en el análisis exploratorio como en el confirmatorio. Los ítems no revelaron discrepancias en las habilidades estimadas de los participantes, y presentaron ajustes estructurales adecuados y opciones de respuestas claras. Respecto a la validez, la escala presentó asociaciones con variables externas -personalidad y bienestar psicológico-; y el análisis SEM demostró una fuerte relación entre el ebadep-a y el Beck Depression Inventory-II, así como una predicción fuerte del primero sobre el segundo (r2 = .65). Se concluye que el factor general del ebadep-a representa adecuadamente los fenómenos psicológicos subyacentes a la depresión, y que la versión final de la escala presenta propiedades psicométricas adecuadas para la población argentina.

Psychometric Properties of the Chinese Version of the Clinically Useful Depression Outcome Scale for Patients with Major Depressive Disorder

OBJECTIVE

This study aimed to evaluate the psychometric properties of the Chinese version of the Clinically Useful Depression Outcome Scale (CUDOS).

METHODS

One hundred ninety patients with major depressive disorder (MDD) according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria were recruited to the study. The English version of the CUDOS was translated into Chinese using a forward and backward translation method, which was according to the guidelines of adaptation and validation of instruments in cross-cultural health care research. The Chinese version of the CUDOS, the 17-item Hamilton Rating Scale for Depression (HRSD) and the improved Clinical Global Impression-Severity Scale (iCGI-S) were used to evaluate depressive symptoms in one hundred ninety patients with MDD. One week after the first evaluation, sixteen patients were selected randomly for a second assessment. Reliability and validity tests and receiver operating characteristic curves were performed.

RESULTS

The internal consistency of the CUDOS was 0.95, and the split-half reliability coefficient of the CUDOS was 0.92. The correlation coefficient of the retest in sixteen patients was 0.77 (P < 0.01). There was a significant difference in the total score of the Chinese version of the CUDOS between the different levels of depression severity groups (P < 0.01). The ability of the CUDOS to identify patients in remission was high (area under ROC curve= 0.97). A cut-off score of 14/15 yielded 90.20% sensitivity and 93.60% specificity when iCGI-S=1.

CONCLUSION

The Chinese version of the CUDOS is valuable as a brief and reliable instrument to assess depressive symptoms and clinical outcome. The findings suggest that the optimal cut-off score to identify patients in remission was 14/15.

Posttraumatic Embitterment Disorder in Patients with Chronic Kidney Disease

Objective

Posttraumatic embitterment disorder (PTED), a subgroup of an adjustment disorder, is a feeling with anger and helplessness. Hemodialysis may be a trigger event leading to PTED. We investigated the prevalence of PTED in patients with each categorized stages of chronic kidney disease (CKD) and the association between PTED and depression and functional impairment.

Methods

Patients were categorized into three groups according to the stages of CKD (stage I–II, III–IV, and V). CKD (I–II) group was defined as estimated glomerular filtration rate (eGFR) >60 ml/min/1.73 m², CKD (III–IV) group as eGFR <60 ml/min/1.73 m², and CKD (V) group as CKD stage V including patients ongoing hemodialysis. Patients were assessed for the prevalence of PTED, depression, and decreased quality of life by using the scale of PTED, Patient Health Questionnaire-9 (PHQ-9), and EuroQol Five Dimensional Questionnaires, Visual Analogue Scale (EQ-5D-VAS), respectively.

Results

A total of 445 patients were analyzed. The number of patients in CKD (I–II) was 166, CKD (III–IV) was 172, and CKD (V) was 107. Multivariate analysis by binomial logistic regression demonstrated that CKD (V) was significantly associated with the prevalence of PTED (odds ratio, 4.13; 95% confidence interval, 1.56–15.6; p=0.006) after adjustment for age, gender, and diabetes mellitus. Also, a significant correlation existed between PTED and EQ-5D-VAS in all stages, but the correlation was nonsignificant between PTED and PHQ-9 score in group CKD (V).

Conclusion

The findings suggest that PTED is underdiagnosed in CKD patients. Acknowledgment and diagnosis of PTED in CKD patients may lead to a better quality of life.

Gender Differences Affecting Psychiatric Distress and Tinnitus Severity

Objective

This study evaluated gender differences in the relationship between psychiatric distress and subjective tinnitus severity.

Methods

This cross-sectional study included 134 female and 114 male patients who visited the otology outpatient clinic at Seoul St. Mary's Hospital for tinnitus from February to July 2015. Patients completed a series of instruments, including the Tinnitus Handicap Inventory, Beck Depression Inventory, Korean version of Brief Encounter Psychosocial Instrument (BEPSI-K), and visual analogue scales assessing various tinnitus characteristics (loudness, awareness, annoyance, and effect on life).

Results

Tinnitus severity did not significantly differ between the gender groups (p=0.632), and it correlated significantly with tinnitus characteristics and psychiatric distress. Partial correlations between tinnitus severity and depressive symptoms were stronger in males (r=0.411, p＜0.01) than in females (r=0.304, p＜0.01) while controlling for duration of tinnitus and tinnitus characteristics. However, stress (BEPSI-K) was positively correlated with tinnitus severity in only males (r=0.463, p＜0.01). A multiple regression analysis revealed that effect of tinnitus on life, depressive symptoms, and stress were significantly associated with tinnitus severity in males, whereas only tinnitus annoyance and depressive symptoms were associated with tinnitus severity in females.

Conclusion

Tinnitus severity was significantly correlated with depressive symptoms and stress, and there were gender differences in the relationship between tinnitus severity and psychiatric components. It is necessary to be vigilant of psychiatric symptoms among patients with tinnitus who visit the otology outpatient clinic, especially for male patients.

A Pharmacogenomic-based Antidepressant Treatment for Patients with Major Depressive Disorder: Results from an 8-week, Randomized, Single-blinded Clinical Trial

Objective

Pharmacogenomic-based antidepressant treatment (PGATx) may result in more precise pharmacotherapy of major depressive disorder (MDD) with better drug therapy guidance.

Methods

An 8-week, randomized, single-blind clinical trial was conducted to evaluate the effectiveness and tolerability of PGATx in 100 patients with MDD. All recruited patients were randomly allocated either to PGATx (n=52) or treatment as usual (TAU, n=48) groups. The primary endpoint was a change of total score of the Hamilton Depression Rating Scale-17 (HAMD-17) from baseline to end of treatment. Response rate (at least 50% reduction in HAMD-17 score from baseline), remission rate (HAMD-17 score ≥7 at the end of treatment) as well as the change of total score of Frequency, Intensity, and Burden of Side Effects Ratings (FIBSER) from baseline to end of treatment were also investigated.

Results

The mean change of HAMD-17 score was significantly different between two groups favoring PGATx by −4.1 point of difference (p=0.010) at the end of treatment. The mean change in the FIBSER score from baseline was significantly different between two treatment groups favoring PGATx by −2.5 point of difference (p=0.028). The response rate (71.7 % vs. 43.6%, p=0.014) were also significantly higher in PGATx than in TAU at the end of treatment, while the remission rate was numerically higher in PGATx than in TAU groups without statistical difference (45.5% vs. 25.6%, p=0.071). The reason for early drop-out associated with adverse events was also numerically higher in TAU (n=9, 50.0%) than in PGATx (n=4, 30.8%).

Conclusion

The present study clearly demonstrate that PGATx may be a better treatment option in the treatment of MDD in terms of effectiveness and tolerability; however, study shortcomings may limit a generalization. Adequately-powered, well-designed, subsequent studies should be mandatory to prove its practicability and clinical utility for routine practice.

Improving the Screening Instrument of Bipolar Spectrum Disorders: Weighted Korean Version of the Mood Disorder Questionnaire

Objective

It is not easy to diagnose bipolar disorders accurately in the clinical setting. Although Korean version of the Mood Disorder Questionnaire (K-MDQ) is easily administered, it still has weakness regarding case finding. In this study, we suggest a new weighted version of the K-MDQ to increase its screening power.

Methods

Ninety-five patients with bipolar disorders and 346 controls (patients with schizophrenia, patients with depressive disorders, patients with anxiety disorders, and subjects without any psychiatric disease) were enrolled in this study. The subjects received brief information on the K-MDQ, and then independently completed the questionnaire.

Results

Using odds ratios, we constructed a new weighted K-MDQ (W-K-MDQ). Item 1 (feel so good or hyper) was weighted 7 times and item 4 (less sleep) 3.5 times. Item 7 (easily distracted) and item 11 (more interested in sex) were excluded. Part 2 (simultaneity) and 3 (functional impairment) were also excluded as in the original K-MDQ. The sensitivity of the W-K-MDQ with a cutoff value of 10 was enhanced to 0.789. The area under the receiver operating characteristic curve was increased to 0.837.

Conclusion

We suggested a new formula for K-MDQ using 11 of its items. The W-K-MDQ can be easily applied with good sensitivity to screen for bipolar disorders in clinical settings in Korea. Further evaluations with larger samples are needed to establish the usefulness of the W-K-MDQ.

Correlations Between Objective Behavioral Features Collected From Mobile and Wearable Devices and Depressive Mood Symptoms in Patients With Affective Disorders: Systematic Review

Background

Several studies have recently reported on the correlation between objective behavioral features collected via mobile and wearable devices and depressive mood symptoms in patients with affective disorders (unipolar and bipolar disorders). However, individual studies have reported on different and sometimes contradicting results, and no quantitative systematic review of the correlation between objective behavioral features and depressive mood symptoms has been published.

Objective

The objectives of this systematic review were to (1) provide an overview of the correlations between objective behavioral features and depressive mood symptoms reported in the literature and (2) investigate the strength and statistical significance of these correlations across studies. The answers to these questions could potentially help identify which objective features have shown most promising results across studies.

Methods

We conducted a systematic review of the scientific literature, reported according to the preferred reporting items for systematic reviews and meta-analyses guidelines. IEEE Xplore, ACM Digital Library, Web of Sciences, PsychINFO, PubMed, DBLP computer science bibliography, HTA, DARE, Scopus, and Science Direct were searched and supplemented by hand examination of reference lists. The search ended on April 27, 2017, and was limited to studies published between 2007 and 2017.

Results

A total of 46 studies were eligible for the review. These studies identified and investigated 85 unique objective behavioral features, covering 17 various sensor data inputs. These features were divided into 7 categories. Several features were found to have statistically significant and consistent correlation directionality with mood assessment (eg, the amount of home stay, sleep duration, and vigorous activity), while others showed directionality discrepancies across the studies (eg, amount of text messages [short message service] sent, time spent between locations, and frequency of mobile phone screen activity).

Conclusions

Several studies showed consistent and statistically significant correlations between objective behavioral features collected via mobile and wearable devices and depressive mood symptoms. Hence, continuous and everyday monitoring of behavioral aspects in affective disorders could be a promising supplementary objective measure for estimating depressive mood symptoms. However, the evidence is limited by methodological issues in individual studies and by a lack of standardization of (1) the collected objective features, (2) the mood assessment methodology, and (3) the statistical methods applied. Therefore, consistency in data collection and analysis in future studies is needed, making replication studies as well as meta-analyses possible.

The Present and Future of Precision Medicine in Psychiatry: Focus on Clinical Psychopharmacology of Antidepressants

Precision medicine is a concept which is recently gaining momentum in all branches of medicine. In particular in psychiatry it is greatly needed given the huge societal costs of psychiatric disorders and given the long time needed to observe benefit from treatments and the response variability. The future will be based on biological determinants, however until such an interesting but still futuristic aim will be reached, at present we may only rely on clinical features to guide our individualized prescription which is currently still frequently based on personal opinion and subjective previous experiences. The aim of this review is to offer an overview of the main aspects to take into consideration when prescribing an antidepressant treatment to reach the best precision medicine using clinical information. More than 40 compounds are available for treating depression and a similar amount of compounds for other psychiatric disorders. The process of matching the profile of the patient with all different profiles of available compounds is therefore quite complex. Our everyday prescribing procedure should take into consideration a number of factors such as the knowledge of the profile of available compounds versus the symptomatology profile of the subject, previous efficacy, medical comorbidities, tolerability profile, individual preferences, and family history. While we are waiting more complex algorithms including biological or genetic measures, it is possible to optimize our current prescription practice by using all available information in order to obtain as much as possible an evidence based precision medicine prescription.

A Korean validation study of the Clinically Useful Anxiety Outcome Scale: Comorbidity and differentiation of anxiety and depressive disorders

Background

This study aimed to evaluate the psychometric properties of the Korean version of the Clinically Useful Anxiety Outcome Scale (CUXOS) and to examine the current diagnostic comorbidity and differential severity of anxiety symptoms between major depressive disorder (MDD) and anxiety disorders.

Methodology

In total, 838 psychiatric outpatients were analyzed at their intake appointment. Diagnostic characteristics were examined using the structured clinical interview from the DSM-IV because the DSM5 was not available at the start of the study. The CUXOS score was measured and compared with that of 3 clinician rating scales and 4 self-report scales.

Principal findings

The CUXOS showed excellent results for internal consistency (Cronbach’s α = 0.90), test–retest reliability (r = 0.74), and discriminant and convergent validity. The CUXOS significantly discriminated between different levels of anxiety severity, and the measure was sensitive to change after treatment. Approximately 45% of patients with MDD were additionally diagnosed with anxiety disorders while 55% of patients with anxiety disorders additionally reported an MDD. There was a significant difference in CUXOS scores between diagnostic categories (MDD only, anxiety only, both disorders, and no MDD or anxiety disorder). The CUXOS scores differed significantly between all categories of depression (major, minor, and non-depression) except for the comparison between minor depression and non-depression groups.

Conclusions

The Korean version of the CUXOS is a reliable and valid measure of the severity of anxiety symptoms. The use of the CUXOS could broaden the understanding of coexisting and differentiating characteristics of anxiety and depression.