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Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Icequakes at or near the bed of a glacier have the potential to allow us to investigate the interaction of ice with the underlying till or bedrock. Understanding this interaction is important for studying basal sliding of glaciers and ice streams, a critical process in ice dynamics models used to constrain future sea-level rise projections. However, seismic observations on glaciers can be dominated by seismic energy from surface crevassing. We present a method of automatically detecting basal icequakes and discriminating them from surface crevassing, comparing this method to a commonly used spectrum-based method of detecting icequakes. We use data from Skeidararjökull, an outlet glacier of the Vatnajökull Ice Cap, South-East Iceland, to demonstrate that our method outperforms the commonly used spectrum-based method. Our method detects a higher number of basal icequakes, has a lower rate of incorrectly identifying crevassing as basal icequakes and detects an additional, spatially independent basal icequake cluster. We also show independently that the icequakes do not originate from near the glacier surface. We conclude that the method described here is more effective than currently implemented methods for detecting and discriminating basal icequakes from surface crevassing.
Previous research suggests that CBT focusing on worry in those with persecutory delusions reduces paranoia, severity of delusions and associated distress. This preliminary case series aimed to see whether it is feasible and acceptable to deliver worry-focused CBT in a group setting to those with psychosis. A secondary aim was to examine possible clinical changes. Two groups totalling 11 participants were run for seven sessions using the Worry Intervention Trial manual. Qualitative and quantitative data about the experience of being in the group was also collected via questionnaires, as was data on number of sessions attended. Measures were delivered pre- and post-group and at 3-month follow-up. These included a worry scale, a measure of delusional belief and associated distress and quality of life measures. Of the 11 participants who started the group, nine completed the group. Qualitative and quantitative feedback indicated that most of the participants found it acceptable and helpful, and that discussing these issues in a group setting was not only tolerable but often beneficial. Reliable Change Index indicated that 6/7 of the group members showed reliable reductions in their levels of worry post-group and 5/7 at follow-up. There were positive changes on other measures, which appeared to be more pronounced at follow-up. Delivering a worry intervention in a group format appears to be acceptable and feasible. Further research with a larger sample and control group is indicated to test the clinical effectiveness of this intervention.
Key learning aims
(1)To understand the role of worry in psychosis.
(2)To learn about the possible feasibility of working on worry in a group setting.
(3)To be aware of potential clinical changes from the group.
(4)To consider acceptability for participants of working on worries in a group setting.
Previous research has shown that psychoeducation for bipolar disorder (BD) improves symptoms and reduces relapse risk, but there is little research on how this impacts stigma, perceived recovery and views about diagnosis. The aim of this study was to explore whether a cognitive behaviour therapy (CBT)-based 12-week BD psychoeducation group conducted in a community mental health team for adults impacted perceived stigma, diagnosis-related self-esteem, recovery and views about diagnosis. The case series pre- and post-group had 23 participants across three groups. The Brief Illness Perception Questionnaire, views on Manic Depression Questionnaire, Bipolar Recovery Questionnaire and author-constructed questions were completed pre and post. Twenty participants completed the group. An intent-to-treat repeated measures multiple analysis of variance showed significantly improved perceived recovery and improvements in sense of control and understanding around their diagnosis. Other specific questions such as understanding of triggers and impact of thinking patterns also improved. However, there was no change in the perceived stigma or self-esteem associated with living with BD. CBT-based psychoeducation groups may help improve perceived recovery and factors such as sense of control in BD. However, there appears to be no impact on stigma and self-esteem, and the role of non-specific factors needs to be examined further.
Key learning aims
(1)To raise awareness of the impact of stigma and self-esteem in bipolar disorder.
(2)To understand the content and structure of CBT-based psychoeducation groups.
(3)To consider the potential benefits of CBT-based psychoeducation groups beyond symptoms and relapse reduction on factors such as perceived recovery.
Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.
To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.
Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.
A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).
The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.
Declaration of interest
Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.
There is growing interest in linking vitamin D deficiency with autism spectrum disorders (ASDs). The association between vitamin D deficiency during gestation, a critical period in neurodevelopment, and ASD is not well understood.
To determine the association between gestational vitamin D status and ASD.
Based on a birth cohort (n=4334), we examined the association between 25-hydroxyvitamin D (25OHD), assessed from both maternal mid-gestation sera and neonatal sera, and ASD (defined by clinical records; n=68 cases).
Individuals in the 25OHD-deficient group at mid-gestation had more than twofold increased risk of ASD (odds ratio (OR)=2.42, 95% confidence interval (CI) 1.09 to 5.07, P=0.03) compared with the sufficient group. The findings persisted in analyses including children of European ethnicity only.
Mid-gestational vitamin D deficiency was associated with an increased risk of ASD. Because gestational vitamin D deficiency is readily preventable with safe, inexpensive and readily available supplementation, this risk factor warrants closer scrutiny.
Computerised cognitive–behavioural therapy (cCBT) for depression has the potential to be efficient therapy but engagement is poor in primary care trials.
We tested the benefits of adding telephone support to cCBT.
We compared telephone-facilitated cCBT (MoodGYM) (n = 187) to minimally supported cCBT (MoodGYM) (n = 182) in a pragmatic randomised trial (trial registration: ISRCTN55310481). Outcomes were depression severity (Patient Health Questionnaire (PHQ)-9), anxiety (Generalized Anxiety Disorder Questionnaire (GAD)-7) and somatoform complaints (PHQ-15) at 4 and 12 months.
Use of cCBT increased by a factor of between 1.5 and 2 with telephone facilitation. At 4 months PHQ-9 scores were 1.9 points lower (95% CI 0.5–3.3) for telephone-supported cCBT. At 12 months, the results were no longer statistically significant (0.9 PHQ-9 points, 95% CI −0.5 to 2.3). There was improvement in anxiety scores and for somatic complaints.
Telephone facilitation of cCBT improves engagement and expedites depression improvement. The effect was small to moderate and comparable with other low-intensity psychological interventions.
Social network analysis is the study of how links between a set of actors are formed. Typically, it is believed that links are formed in a structured manner, which may be due to, for example, political or material incentives, and which often may not be directly observable. The stochastic blockmodel represents this structure using latent groups which exhibit different connective properties, so that conditional on the group membership of two actors, the probability of a link being formed between them is represented by a connectivity matrix. The mixed membership stochastic blockmodel extends this model to allow actors membership to different groups, depending on the interaction in question, providing further flexibility.
Attribute information can also play an important role in explaining network formation. Network models which do not explicitly incorporate covariate information require the analyst to compare fitted network models to additional attributes in a post-hoc manner. We introduce the mixed membership of experts stochastic blockmodel, an extension to the mixed membership stochastic blockmodel which incorporates covariate actor information into the existing model. The method is illustrated with application to the Lazega Lawyers dataset. Model and variable selection methods are also discussed.
The excavations of Frans Blom and Clarence Weiant at the small hilltop site of Moxviquil in the early 1950s represent one of the pioneering archaeological projects in highland Chiapas. The results of their excavations, which were minimally published, provide important data on one of the largest Late Classic-Early Postclassic communities in the region. In this paper, we reconsider Moxviquil in light of recent scholarship on Maya urbanism, and present new interpretations of the site as a small city that fulfilled a diversified set of urban functions for residents both within the monumental zone itself, and in the surrounding hinterland areas. Consistent with its likely role as the administrative center of a small, independent highland polity, the monumental center of Moxviquil likely served political, economic, and ritual functions; was an important nucleus of residential settlement; and supported a wide range of household-based craft production and food preparation activities.
A kinetic model of the Boltzmann equation for non-vibrating polyatomic gases is proposed, based on the Rykov model for diatomic gases. We adopt two velocity distribution functions (VDFs) to describe the system state; inelastic collisions are the same as in the Rykov model, but elastic collisions are modelled by the Boltzmann collision operator (BCO) for monatomic gases, so that the overall kinetic model equation reduces to the Boltzmann equation for monatomic gases in the limit of no translational–rotational energy exchange. The free parameters in the model are determined by comparing the transport coefficients, obtained by a Chapman–Enskog expansion, to values from experiment and kinetic theory. The kinetic model equations are solved numerically using the fast spectral method for elastic collision operators and the discrete velocity method for inelastic ones. The numerical results for normal shock waves and planar Fourier/Couette flows are in good agreement with both conventional direct simulation Monte Carlo (DSMC) results and experimental data. Poiseuille and thermal creep flows of polyatomic gases between two parallel plates are also investigated. Finally, we find that the spectra of both spontaneous and coherent Rayleigh–Brillouin scattering (RBS) compare well with DSMC results, and the computational speed of our model is approximately 300 times faster. Compared to the Rykov model, our model greatly improves prediction accuracy, and reveals the significant influence of molecular models. For coherent RBS, we find that the Rykov model could overpredict the bulk viscosity by a factor of two.