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The main aim of the current study was to present the abilities of widely used crop models to simulate four different field crops (winter wheat, spring barley, silage maize and winter oilseed rape). The 13 models were tested under Central European conditions represented by three locations in the Czech Republic, selected using temperature and precipitation gradients for the target crops in this region. Based on observed crop phenology and yield from 1991 to 2010, performances of individual models and their ensemble were analyzed. Modelling of anthesis and maturity was generally best simulated by the ensemble median (EnsMED) compared to the ensemble mean and individual models. The yield was better simulated by the best models than estimated by an ensemble. Higher accuracy was achieved for spring crops, with the best results for silage maize, while the lowest accuracy was for winter oilseed rape according to the index of agreement (IA). Based on EnsMED, the root mean square errors (RMSEs) for yield was 1365 kg/ha for winter wheat, 1105 kg/ha for spring barley, 1861 kg/ha for silage maize and 969 kg/ha for winter oilseed rape. The AQUACROP and EPIC models performed best in terms of spread around the line of best fit (RMSE, IA). In some cases, the individual models failed. For crop rotation simulations, only models with reasonable accuracy (i.e. without failures) across all included crops within the target environment should be selected. Application crop models ensemble is one way to increase the accuracy of predictions, but lower variability of ensemble outputs was confirmed.
Estuarine habitats are major nurseries for the European flounder Platichthys flesus, with different year classes sharing food and space resources. Hence, an understanding of feeding strategies that optimize resource use and maintain carrying capacity is fundamental for sustainable and successful ecosystem management. The main feeding areas of juvenile European flounder (including 0-group and 1-group age classes) in the Lima estuary (northern Portugal) nursery ground were investigated by integrating stomach content analyses with stable isotopic values (δ13C and δ15N) and fish condition indices (Fulton K and RNA:DNA ratio). The 0-group flounder that were associated with the upstream section of the estuary presented the lowest δ13C value (−25.58 ± 1.86‰), while 1-group flounder exhibited a higher δ13C value (−22.59 ± 2.51‰), indicating use of the more saline areas of the estuary (lower and middle sections). The two age groups did not differ in terms of δ15N (0-group: 13.93 ± 0.29‰; 1-group: 13.50 ± 0.96‰), indicating similar trophic levels. The low salinity upper estuary was the main feeding area of 0-group flounder (74%), while 1-group flounder fed along the estuary both upstream (52%) and downstream (48%). Juvenile flounder showed high individual condition based on the Fulton K index (0-group: 1.05 ± 0.08; 1-group: 1.07 ± 0.05) and RNA:DNA (0-group: 1.70 ± 0.70; 1-group: 1.41 ± 0.47). These indices deal with fish health, and hence indicate nursery habitat quality. It is concluded that in this temperate nursery habitat, different feeding strategies sustained the condition of the European flounder juveniles, compared with other flounder populations.
We consider Stavskaya’s process, which is a two-state probabilistic cellular automaton defined on a one-dimensional lattice. The state of any vertex depends only on itself and on the state of its right-adjacent neighbour. This process was one of the first multicomponent systems with local interaction for which the existence of a kind of phase transition has been rigorously proved. However, the exact localisation of its critical value remains as an open problem. We provide a new lower bound for the critical value.
Implementation of genome-scale sequencing in clinical care has significant challenges: the technology is highly dimensional with many kinds of potential results, results interpretation and delivery require expertise and coordination across multiple medical specialties, clinical utility may be uncertain, and there may be broader familial or societal implications beyond the individual participant. Transdisciplinary consortia and collaborative team science are well poised to address these challenges. However, understanding the complex web of organizational, institutional, physical, environmental, technologic, and other political and societal factors that influence the effectiveness of consortia is understudied. We describe our experience working in the Clinical Sequencing Evidence-Generating Research (CSER) consortium, a multi-institutional translational genomics consortium.
A key aspect of the CSER consortium was the juxtaposition of site-specific measures with the need to identify consensus measures related to clinical utility and to create a core set of harmonized measures. During this harmonization process, we sought to minimize participant burden, accommodate project-specific choices, and use validated measures that allow data sharing.
Identifying platforms to ensure swift communication between teams and management of materials and data were essential to our harmonization efforts. Funding agencies can help consortia by clarifying key study design elements across projects during the proposal preparation phase and by providing a framework for data sharing data across participating projects.
In summary, time and resources must be devoted to developing and implementing collaborative practices as preparatory work at the beginning of project timelines to improve the effectiveness of research consortia.
Nowadays several authors defend the existence of an obsessive-compulsive (OC) spectrum in which eating disorders (ED), especially anorexia nervosa, would be include. We investigated the presence of OC symptoms in bulimic and anorexic patients and its relationships with personality traits.
The Maudsley Obsessive Compulsive Questionnaire (MOCQ) and the revised version of the Temperament and Character Inventory (TCI-R) were administered to patients and healthy controls.
Patients show higher scores than controls in the global punctuation of de MOCQ, and in the checking and doubt subscales. Cases also score higher in harm avoidance (dimension associated with personality disorders of cluster C) and in its subscale anticipatory worry. No differences were found between patients subgroups.
Restricting Anorexia Nervosa (RAN, n = 21)
Binging-Purging Anorexia Nervosa (BPAN, n = 29)
Bulimia Nervosa (BN, n = 34)
Control (C, n = 52)
RAN, BPAN, BN > C
Checking subscale (MOCQ)
BPAN, BN > C
RAN, BPAN, BN > C
Harm avoidance (TCI-R)
BPAN, BN > C
Anticipatory worry vs optimism (TCI-R)
RAN, BPAN, BN > C
Patients present more OC behaviours in comparison with healthy population but measures of obsessivity do not differ between the types of ED. Traits of personality characteristically associated to cluster C and to anxiety disorders seem to be also common features. These results do not support a separated classification of RAN into the OC spectrum.
To determine the clinical profile of patients diagnosed of delusional disorder (DD) admitted to a psychiatric ward.
Retrospective chart review of inpatients with diagnoses of delusional disorder (DD) according ICD-10 criteria admitted to a psychiatric ward (Hospital de Conxo, Santiago de Compostela) between January 1998 and December 2008. Sociodemographic and clinical variables were collected, with special attention to comorbidity and presumed risk factors.
The sample consisted in 56 inpatients (30 women, mean age 54 ± 11). 64.3% were single including never married (33.9%), divorced, separated and widowed and 33.9% lived alone. The most frequent type of DD was persecutory (67%) followed by mixed type (16%). 16.1% presented hallucinations (most frequent auditory). In comparison with the other types, patients with persecutory delusions usually lived alone (p < 0.05). Most frequent comorbidities were substance abuse and affective disorders. Familiar background of psychoses was recorded in 21.4% and history of emigration in 12.5%. 5.4% suffered deafness. During the period studied 53.6% were admitted two or more times. After the most recent admission 32.1% were on depot antipsychotic.
In concordance with other previous reports, DD seemed to be more prevalent in women in middle or late adulthood and persecutory were the most frequent delusions. In our sample, most patients were not married and high prevalence of family antecedents of psychoses was found. It could be related with its hospital origin; then it could be hypothesized living alone and having familiar background of psychoses to be risk factors of hospitalization.
The aim of this study is to assess the personality traits in a sample of Spanish anorexic and bulimic outpatients.
The revised version of the Temperament and Character Inventory was administered to 76 women attended in an Eating Disorders Unit and to 46 healthy controls. Both groups were matched by gender, age and instruction.
Diagnoses in the sample were distributed as follows: bulimia nervosa (BN) 33, binging-purging type anorexia nervosa (BPAN) 23 and restricting anorexia nervosa (RAN) 18. RAN patients were significantly younger (21.6 vs. 26.3 p < 0.01). Differences in the harm avoidance, persistence and selfdirectedness subscales of the TCI were found (see table).
BPAN, BN > C
RAN > C
C > RAN, BPAN, BN
In concordance with previous reports, compared with healthy controls, patients show lower scores in self-directedness. Persistence seems to be associated with restricting behaviours, whereas harm avoidance with binging and purging. RAN trends to have low scores in novelty seeking items and BN shows lower reward dependence, but this differences are not statistically significant, perhaps because of sample size.
To compare the efficacy and safety of the intramuscular formulations of ziprasidone and haloperidol in treating agitation in schizophrenic patients attended in an emergency room.
Consecutive patients were alternatively assigned to receive 20 mg of IM ziprasidone or 10 mg of IM haloperidol. Efficacy measures were improvement in Behavioral Activity Rating Scale (BARS), in the sum of five items of the Positive and Negative Syndrome Scale that focused on agitation (PANSS-A) and scores on the Clinical Global Impression improvement scale (CGI-I), obtained 45 minutes and 2 hours after the IM medication. Tolerability assessments included changes in ECG, monitoring of vital signs and register of adverse events.
Finally 18 patients (13 men, mean age 40.8 ±10.2) were included in the analysis of data. At arrival in the emergency room, there were no differences between ziprasidone (Z) and haloperidol (H) groups in age, mean QTc length, mean BARS and mean PANSS-A scores. Analyzing the global sample there was an improvement in agitation scores. No significant differences were found between the groups in change of BARS and PANSS-A scores, in CGI-I scores or in the variation of the length of QTc interval at two hours. No serious adverse events were reported.
In spite of the small sample size, both treatments ziprasidone IM and haloperidol IM seems to be similarly effective for the management of psychotic agitation in the emergency room. Both were well tolerated. Lengthening of QTc interval due to ziprasidone IM had not been found in our sample.
To explore the relationship between symptomatic and functional outcomes in adults (age 18-65 years) with ADHD during open label treatment with PR OROS MPH.
Post hoc analyses of a 7-week open-label extension (OLE) (N=370) of a 5 week, placebo controlled double-blind study (DB) which explored safety, efficacy, functional and quality of life outcomes in subjects with a diagnosis of ADHD (DSM-IV). Medication was flexibly dosed (18-90 mg/day) and adjusted individually to best effect during OLE. Regression analyses were performed on the change from DB baseline at OL endpoint in functionality and quality of life as measured by the Sheehan Disability Scale (SDS) and Quality of Life (Q-LES-Q). Baseline score, country, randomization group, sex, change from baseline in CAARS Hyperactivity / Impulsivity, CAARS Inattention and CGI-S at DB endpoint were included as covariates in the analyses.
337 / 370 patients completed the 7-week open label treatment. Improvement on CAARS Hyperactivity / Impulsivity at DB endpoint was significantly related with improvement in SDS “work”, “social life”, “family life” (at least p< 0.005) and “total score” as well as quality of life (p< 0.05) at the end of open label treatment. Change in CGI-S and CAARS Inattention at DB endpoint vs. DB baseline were not related with improvements in any of the functional or quality of life scales at OL endpoint (p>0.05).
These results indicate that improvement in daily functioning and QOL under active treatment may be particularly related to improvement in hyperactivity symptoms.
Adult attention deficit hyperactivity disorder (ADHD) has a prevalence up to 4% of the general adult population, however in Spain adult ADHD is underdiagnosed. Screening instruments can help clinicians to detect adult ADHD. The World Health Organization Adult ADHD Self-Report Scale-Version 1.1 (ASRS v1.1) is a 6-question scale designed to screen for adult ADHD.
A validation of Spanish version of the ASRS v1.1 was performed.
A case control study was carry out (adult ADHD vs non ADHD) in the Adult ADHD Program of the Hospital Universitari Vall d'Hebron (Barcelona). ADHD evaluation was performed using Conners Adult ADHD Diagnostic Interview for DSM-IV (CAADID-Part II) and the diagnosis was compared with the ASRS v1.1 responses. Logistic regression study was made to evaluate the sensitivity, specificity, positive and negative predictive values (PPV and NPV). Kappa coefficient of classification accuracy and area under curve (AUC) were calculated.
Sample consisted of 90 adult ADHD and 90 controls. Average age was 31.6 (SD=10.09) and 57.8% of subjects were men (there were no significant differences between the two groups). Logistic regression analysis showed that the score model proposed by the authors of scale is significant (c2 =129.36, p=.0005): Sensitivity (82.2%), specificity (95.6%), PPV (94.8%), NPV (84.3%), Kappa coefficient 0.78 and AUC 0.89.
The Spanish version of the ASRS v1.1 6-question shows adequate psychometric characteristics and it is a valid scale to screen ADHD for adults in a clinical setting.
Immigration to Spain is a recent but rapidly growing fenomena. The prevalence of psychiatric disorders in the immigrants relative to natives is an inconclusive theme, given that several studies have found contradictory results.
This study presents sociodemographic characteristics and the prevalence of mood disorders (detected with MINI) of 842 adults (411 Latinos and 431 Natives), attending primary care in the greater Barcelona metropolitan area.
Most of the sample was female (n=591; 70.2%), the mean age was 34.7 (±9.8) years, range 18-65. Significant (p< 0,001) differences were found between the two groups in: scholarization, housing, work status, income and percived social network.
The prevalence of actual major depresssive disorder (MDD) was 12.7% in the total sample, with a higer prevalence in the Latinos (n=68; 16.5%) than Natives (n=39; 9.0%); p=0.001 X2=10.57.There was no difference in total prevalences of other mood disorders between the two groups. Analysis -through logistic regression- of only those patients with complete data, (n=613; 307 Latinos and 306 Natives) showed that the probability of MDD was higer in Latinos than in Native patients (OR= 2.4; 95% CI= 1.5-4.0). After adjusting for gender and all the significantly different variables, the higer risk of MDD in Latinos disappeared (OR= 1.3; 95% CI= 0.7-2.4).
From these data we can conlude that the relation between immigrant status and depression is not direct but rather mediated by disadvantaged social conditions. In further similar studies social variables should be considered.
Attention Deficit Hyperactivity Disorder (ADHD)presents high levels of life-long comorbidity. Several studies demonstrate an elevated coocurrence between ADHD and Substance Use Disorder (SUD) as well as personality disorders.
The objective of this poster is to demonstrate differential characteristics between ADHD with SUD patients versus ADHD without SUD, in relation to Axis II comorbidity, ADHD symptoms severity and childhood behavioural disorders (conduct disorder and oppositional defiant disorder).
Another objective is to identify differences in the prevalence of SUD relative to gender and ADHD subtype (Inattentive, Hyperactive/Impulsive and Combined).
This will be done using a comparative-descriptive study that was carried out with a sample of 125 adults diagnosed with ADHD using the CAADID in the Adult ADHD Integral Programme (PIDAA) of Vall d'Hebron Universitari Hospital; 53 subjects presented associated SUD (DSM-IV). All the subjects were evaluated with ADHD Rating Scale, SCID-I, SCID-II and K-SADS.
Relative to ADHD group, subjects ADHD with SUD subjects showed higher comorbidity with Axis–II Disorders, especially with antisocial, schizoid and paranoid personality disorders, as well as major prevalence of conductual disorder and oppositional defiant disorder in childhood. There were no significant differences respect to ADHD symptoms severity nor ADHD subtype between both groups. A major proportion of men were observed in ADHD with SUD group compared to ADHD patients.
Impulsive behaviours (impulse control deficit) and compulsive behaviours (over control) have been considered at the core of different disorders, but patients often present with mixed features of impulsive and compulsive behaviours (i.e. patients with OCD and borderline personality disorder). Therefore, a clinical spectrum from impulsivity to compulsivity could exist, in which obsessive compulsive disorder (OCD) and impulsive personality disorders (borderline personality disorder, antisocial personality disorder…) would be the endpoints.
Regarding treatment, SSRI have demonstrated high efficacy in the treatment of both impulsive and obsessive-compulsive symptoms. On the other hand, topiramate has been described as an effective agent in treating impulsive behavior.
The aim of this study is to test the hypothesis that coadjuvant treatment with SSRI and topiramate would improve the outcome of patients with comorbid OCD and impulsive behaviour disorders.
We will describe two clinical cases admitted to our Psychiatric Hospitalization Unit. Case 1 is a 39 years old female diagnosed with OCD, borderline personality disorder and alcohol dependence and case 2 is a 38 years old male with OCD, mixed personality disorder and cocaine abuse.
Treatment with topiramate (range dosage: 250-400 mg/daily) as well as SSRI (paroxetine 40 mg/daily- case 1; sertraline 200 mg/daily-case 2) improved affective instability and impulsive symptoms in both patients. Topiramate was well tolerated without important side effects.
Topiramate could be an interesting alternative in the coadjuvant treatment of OCD with impulsive features.
Musical hallucinations are a rare phenomenon in clinical practice. The purpose of this study was to analyze the clinical spectrum of musical hallucinations.
We analysed demographic and clinical features of cases published in English, Italian, French or Spanish between 1991 and 2006 registered in MEDLINE, including three of our own cases. The cases were separated into four groups according to their main diagnoses (hearing impairment; psychiatric disorder; neurological disorder; toxic or metabolic disorder).
115 patients with musical hallucinations were included, of which 63.5% were female. The mean age was 57,25 years. Main diagnoses were: psychiatric disorder (46.1%; schizophrenia 30.4%), neurological disorder (21,7%), hearing impairment (17,4%), toxic or metabolic disorder (12.2%) and 2.6% other diagnoses.
61.7% patients presented simple diagnoses while 36.5% presented two or more diagnoses. 2.1% of patients didn't receive any diagnoses. 35.7% of patients and 60.9% of non psychiatric patients presented hearing impairment.
Both instrumental and vocal were the more frequent musical hallucinations and most of the patients had insight about the abnormality of their perceptions. Another kind of hallucinations was present in 40.9% of patients, auditory hallucinations being the most common. Also, 38,3% of the global sample had abnormalities in brain structural image (MRI, CT).
Musical hallucinations are a heterogeneous phenomenon in clinical practice. published cases describe them as more common in women and in psychiatric and neurological patients. Hearing impairment seem to be an important risk factor in the development of musical hallucinations.
Psychiatric and psychological testing are used extensively in both clinical and research contexts, with the goal of providing an objective indication of the construct being measured. At the same time, it has long been recognized that there is no such thing as a culture free or even fair test, to the extent that cultural bias-the constant and systematic statistical error due not to chance but to ethnic group membership-can seriously undermine the validity of a psychological or psychiatric test. The very construct being measured may not have a culturally compatible equivalent, or, relatedly, the behavior sampled in a given item or combination of items may not be associated with the construct in question in the same way across all cultures. In addition the means by which the behavior is sampled-the instrument construction, the sorts of questions or their structure, for example-can vary in familiarity across cultures. Finally, the individual items themselves may be poorly or ambiguously translated, may be predicated on specific cutlural norms, or, indeed, the meaning of the item can vary cross-culturally. Finally, sampling bias pertains to the representativeness of the sample, however, this is all the more complex given that constructs such as “race”, “ethnic group” and so forth are often poorly defined and ambiguous, and thus who is and who is not included in a given group may further undermine the validity of the test. Despite these difficulties, concrete steps can be taken to increase the cultural validity of the test used.
Auditory and musical hallucinations have been reported in patients as an adverse effect of the use of opioids. Hearing loss, old age, and female gender are considered risk factors in the development of musical hallucinations. The aim of this report is to describe a case of a patient with auditory and musical hallucinations and to discuss the role of an opioid –tramadol- in the origin of those.
An 80 years old woman experiencing auditory hallucinations was referred to our hospital from an emergency room. The patient had bilateral mild hearing loss and was receiving tramadol 112.5 mg/daily during the last year for cervical pain. In the last ten months, she had been gradually noticing the voice of her dead husband coming from under her pillow, as well as intermittently hearing popular songs being played inside her head. The patient had good insight on both types of abnormal perceptions, which were reported as increasingly unpleasant through time.
Tramadol was discontinued and pimocide (range 1-4 mg/day) and loracepam (2.5 mg/day) were introduced, achieving the improvement of the hallucinations and the anxiety associated with them.
The outcome of this case supports the hypotheses that Opioids could induce musical hallucinations. Hearing impairment, old age, and gender could be underlying risk factors on the development of musical hallucinations.
The relationship between immigration and psychopathology is increasingly understood to be indirect and moderated by the stressors related to the migratory process. Empirical study of acculturative stress has been hindered by the lack of an instrument sensitive to the local immigration context. The Barcelona Immigration Stress Scale (BISS) was developed for as a response to this lack. A four factor model is hypothesized as constituting acculturative stress: (1) stress related to the migratory process (homesickness); (2) stress related to the acculturative process (culture shock); (3) stress related to perceived discrimination; and (4) general psychosocial stress. The objective of this study was to evaluate the internal validity of the BISS.
The BISS was administered to 500 immigrant patients who participated in a study concerned with psychopathology and immigration. Internal consistency was estimated on the basis of the Cronbach alpha and a maximum likelihood factor analysis was carried out with a prior direct oblim rotation.
The BISS has satisfactory internal consistency. Preliminary findings confirmed the four factor model which explained a significant proportion of the common variance.
The BISS is internally valid and supports the hypothesized model of acculturative stress. Future studies will establish the external validity of the BISS comparing the scale to related instruments and to determine if acculturative stress is predictive of psychopathology.
Once daily (q.d.) osmotic release oral system (OROS) methylphenidate has demonstrated to be as efficacious as three times a day (t.i.d.) immediate release (IR) methylphenidate in children with attention deficit hyperactivity disorder (ADHD) but with superior adherence. However, although ADHD continues into adulthood, data in adults are lacking. Effectiveness, adherence to treatment and patient's satisfaction were studied in adults with ADHD before and after switching from methylphenidate IR to OROS presentation.
Seventy newly diagnosed adults with ADHD were treated with t.i.d. methylphenidate IR and, after 3 months, were switched to q.d. OROS formulation and were followed up during 3 additional months. Effectiveness was evaluated with the ADHD Rating Scale (ADHD-RS) and the Clinical Global Impression Improvement (CGI-I) Scale, adherence to treatment with the Simplified Medication Adherence Questionnaire (SMAQ) and patient satisfaction with the treatment. Effectiveness, adherence and satisfaction were compared before and after treatment switch.
ADHD-RS score changed from 34.6 (10.9) at baseline to 25.1 (9.1) while receiving IR methylphenidate and to 15.1 (7.2) while on OROS formulation. Furthermore, methylphenidate switch was associated with an increase of the rate of patients repondents to treatment, from 28.6% to 91.4%. The administration of methylphenidate OROS was associated with better scores in all items of the SMAQ. Methylphenidate OROS was preferred by 97% of patients. All differences were statistically significant. In conclusion, switch from t.i.d. IR to q.d. OROS methylphenidate was associated with an improvement in adherence, patient's satisfaction, and effectiveness.
A small subset of patients with above average admissions to psychiatric inpatient units is recognized in clinical practice. These frequent users tend to be younger and to have a diagnosis of schizophrenia or affective disorder. Social conditions and the severity of the illness seem to be associated with this increased number of admissions.
To study demographic and clinical characteristics of frequent and non-frequent users of a psychiatric inpatient unit.
Retrospective data of all the patients admitted to a psychiatric inpatient unit from January 2004 to December 2008 were reviewed. Frequent-users were defined as patients with 3 or more admissions over that period of time, and non-frequent users as those with less than 3 admissions. The two groups were compared in terms of age, gender, ethnicity, psychiatric diagnosis and compulsory admissions
In a total of 2018 admissions and 1348 patients, the frequent-user group represented 10.2% (n = 137) of the patients and 28.9%(n = 584) of the admissions. Frequent-users were significantly younger (39.5 vs. 44.5 years, p = .001), more frequently black (22.6 vs. 19.4%, p < .001) and compulsorily admitted (27.7 vs. 14%, p < .001) than non-frequent users. Patients with bipolar disorder (p = .001), schizophrenia (p = .003) belonged significantly more to frequent-users group, while unipolar depressive patients (p = .016) and other diagnosis (p = .011) was more significantly represented in the non-frequent users group. Frequency of admission did not differ with gender.
The results concerning age and psychiatric diagnosis are consistent with previous studies. Compulsory admissions and black ethnicity were significantly higher among frequent- users.
Verbal working memory span is decreased in patients with schizophrenia, and this might contribute to impairment in higher cognitive functions as well as to the formation of certain clinical symptoms. Processing speed has been identified as a crucial factor in cognitive efficiency in this population. We tested the hypothesis that decreased processing speed underlies the verbal working memory deficit in patients and mediates the associations between working memory span and clinical symptoms.
Forty-nine schizophrenia inpatients recruited from units for chronic and acute patients, and forty-five healthy participants, were involved in the study. Verbal working memory span was assessed by means of the letter-number span. The Digit Copy test was used to assess motor speed, and the Digit Symbol Substitution Test to assess cognitive speed.
The working memory span was significantly impaired in patients (F(1,90) = 4.6, P < 0.05). However, the group difference was eliminated when either the motor or the cognitive speed measure was controlled (F(1,89) = 0.03, P = 0.86, and F(1,89) = 0.03, P = 0.88). In the patient group, working memory span was significantly correlated with negative symptoms (r = –0.52, P < 0.0001) and thought disorganisation (r = –0.34, P < 0.025) scores. Regression analyses showed that the association with negative symptoms was no longer significant when the motor speed measure was controlled (β = –0.12, P = 0.20), while the association with thought disorganisation was no longer significant when the cognitive speed measure was controlled (β = –0.10, P = 0.26).
Decrement in motor and cognitive speed plays a significant role in both the verbal working memory impairment observed in patients and the associations between verbal working memory impairment and clinical symptoms.