Dysexecutive difficulty and subtle everyday functional disabilities: the digital Trail Making Test

Background

Digital neuropsychological tests reliably capture real-time, process-based behavior that traditional paper/pencil tests cannot detect, enabling earlier detection of neurodegenerative illness. We assessed relations between informant-based subtle and mild functional decline and process-based features extracted from the digital Trail Making Test-Part B (dTMT-B).

Methods

A total of 321 community-dwelling participants (56.0% female) were assessed with the Functional Activities Questionnaire (FAQ) and the dTMT-B. Three FAQ groups were constructed: FAQ = 0 (unimpaired); FAQ = 1-4 (subtle impairment); FAQ = 5-8 (mild impairment).

Results

Compared to the FAQ-unimpaired group, other groups required longer pauses inside target circles (p < 0.050) and produced more total pen strokes to complete the test (p < 0.016). FAQ-subtle participants required more time to complete the entire test (p < 0.002) and drew individual lines connecting successive target circles slower (p < 0.001) than FAQ-unimpaired participants. Lines connecting successive circle targets were less straight among FAQ-mild, compared to FAQ-unimpaired participants (p < 0.044). Using stepwise nominal regression (reference group = FAQ-unimpaired), pauses inside target circles classified other participants into their respective groups (p < 0.015, respectively). Factor analysis using six dTMT-B variables (oblique rotation) yielded a two-factor solution related to impaired motor/cognitive operations (48.96% variance explained) and faster more efficient motor/cognitive operations (28.88% variance explained).

Conclusion

Digital assessment technology elegantly quantifies occult, nuanced behavior not previously appreciated, operationally defines critical underlying neurocognitive constructs related to functional abilities, and yields selected process-based scores that outperform traditional paper/pencil test scores for participant classification. When brought to scale, the dTMT-B test could be a sensitive tool to detect subtle-to-mild functional deficits in emergent neurodegenerative illnesses.

Estimating dementia risk in an African American population using the DCTclock

The prevalence of Alzheimer's disease (AD) and related dementias (ADRD) is increasing. African Americans are twice as likely to develop dementia than other ethnic populations. Traditional cognitive screening solutions lack the sensitivity to independently identify individuals at risk for cognitive decline. The DCTclock is a 3-min AI-enabled adaptation of the well-established clock drawing test. The DCTclock can estimate dementia risk for both general cognitive impairment and the presence of AD pathology. Here we performed a retrospective analysis to assess the performance of the DCTclock to estimate future conversion to ADRD in African American participants from the Rush Alzheimer's Disease Research Center Minority Aging Research Study (MARS) and African American Clinical Core (AACORE). We assessed baseline DCTclock scores in 646 participants (baseline median age = 78.0 ± 6.4, median years of education = 14.0 ± 3.2, 78% female) and found significantly lower baseline DCTclock scores in those who received a dementia diagnosis within 3 years. We also found that 16.4% of participants with a baseline DCTclock score less than 60 were significantly more likely to develop dementia in 5 years vs. those with the highest DCTclock scores (75-100). This research demonstrates the DCTclock's ability to estimate the 5-year risk of developing dementia in an African American population. Early detection of elevated dementia risk using the DCTclock could provide patients, caregivers, and clinicians opportunities to plan and intervene early to improve cognitive health trajectories. Early detection of dementia risk can also enhance participant selection in clinical trials while reducing screening costs.

Digital Clock and Recall is superior to the Mini-Mental State Examination for the detection of mild cognitive impairment and mild dementia

BACKGROUND

Disease-modifying treatments for Alzheimer's disease highlight the need for early detection of cognitive decline. However, at present, most primary care providers do not perform routine cognitive testing, in part due to a lack of access to practical cognitive assessments, as well as time and resources to administer and interpret the tests. Brief and sensitive digital cognitive assessments, such as the Digital Clock and Recall (DCR™), have the potential to address this need. Here, we examine the advantages of DCR over the Mini-Mental State Examination (MMSE) in detecting mild cognitive impairment (MCI) and mild dementia.

METHODS

We studied 706 participants from the multisite Bio-Hermes study (age mean ± SD = 71.5 ± 6.7; 58.9% female; years of education mean ± SD = 15.4 ± 2.7; primary language English), classified as cognitively unimpaired (CU; n = 360), mild cognitive impairment (MCI; n = 234), or probable mild Alzheimer's dementia (pAD; n = 111) based on a review of medical history with selected cognitive and imaging tests. We evaluated cognitive classifications (MCI and early dementia) based on the DCR and the MMSE against cohorts based on the results of the Rey Auditory Verbal Learning Test (RAVLT), the Trail Making Test-Part B (TMT-B), and the Functional Activities Questionnaire (FAQ). We also compared the influence of demographic variables such as race (White vs. Non-White), ethnicity (Hispanic vs. Non-Hispanic), and level of education (≥ 15 years vs. < 15 years) on the DCR and MMSE scores.

RESULTS

The DCR was superior on average to the MMSE in classifying mild cognitive impairment and early dementia, AUC = 0.70 for the DCR vs. 0.63 for the MMSE. DCR administration was also significantly faster (completed in less than 3 min regardless of cognitive status and age). Among 104 individuals who were labeled as "cognitively unimpaired" by the MMSE (score ≥ 28) but actually had verbal memory impairment as confirmed by the RAVLT, the DCR identified 84 (80.7%) as impaired. Moreover, the DCR score was significantly less biased by ethnicity than the MMSE, with no significant difference in the DCR score between Hispanic and non-Hispanic individuals.

CONCLUSIONS

DCR outperforms the MMSE in detecting and classifying cognitive impairment-in a fraction of the time-while being not influenced by a patient's ethnicity. The results support the utility of DCR as a sensitive and efficient cognitive assessment in primary care settings.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04733989.

Clinical classification of memory and cognitive impairment with multimodal digital biomarkers

INTRODUCTION

Early detection of Alzheimer's disease and cognitive impairment is critical to improving the healthcare trajectories of aging adults, enabling early intervention and potential prevention of decline.

METHODS

To evaluate multi-modal feature sets for assessing memory and cognitive impairment, feature selection and subsequent logistic regressions were used to identify the most salient features in classifying Rey Auditory Verbal Learning Test-determined memory impairment.

RESULTS

Multimodal models incorporating graphomotor, memory, and speech and voice features provided the stronger classification performance (area under the curve = 0.83; sensitivity = 0.81, specificity = 0.80). Multimodal models were superior to all other single modality and demographics models.

DISCUSSION

The current research contributes to the prevailing multimodal profile of those with cognitive impairment, suggesting that it is associated with slower speech with a particular effect on the duration, frequency, and percentage of pauses compared to normal healthy speech.

Challenges and prerequisites of risk management program in the operating rooms of Iranian hospitals: A qualitative study

BACKGROUND

The World Health Organization (WHO) considers a safe operating room as one of the necessities of hospitals that support patients. Achieving safety in surgical operations in all countries of the world is the basic goal of healthcare centers and organizations; hence, the present study investigated the challenges and prerequisites for the implementation of an active risk management program in the operating rooms of Iranian hospitals.

MATERIALS AND METHODS

This qualitative-phenomenological study was conducted in 2022. Data were collected using semi-structured interviews, targeted sampling, and the participation of 20 experts (health policy and management experts and academic officials and faculty members of universities) and executive staff (nurses and operating room technicians, doctors and surgical specialists, and officials of surgical departments) and were analyzed using the framework analysis method.

RESULTS

In the resulting qualitative study, the challenges and prerequisites for active risk management in the operating room from the point of view of experts and executive staff were divided into three sub-themes. These three themes include managerial challenges and prerequisites, organizational resources (financial resources, human resources, equipment, and facilities), and cultural issues.

CONCLUSION

Considering managerial prerequisites, organizational resources (financial, human, equipment, and facilities), cultural issues, and removing challenges, an active risk management program in the operating room can be implemented correctly. With the correct implementation of this program, injuries in the operating room for personnel and patients will be greatly reduced, and the satisfaction of beneficiaries and the productivity of the hospital will be greatly increased.

Shortened Motor Evoked Potential Latency in the Epileptic Hemisphere of Children With Focal Epilepsy

PURPOSE

Motor evoked potential (MEP) amplitude and latency are acquired routinely during neuronavigated transcranial magnetic stimulation, a method of functional mapping of the motor cortex before epilepsy surgery. Although MEP amplitude is routinely used to generate a motor map, MEP latency in patients with focal epilepsy has not been studied systematically. Given that epilepsy may alter myelination, we tested whether intrinsic hand muscle MEPs obtained from the hemisphere containing a seizure focus differ in latency from MEPs collected from the opposite hemisphere.

METHODS

Latencies of abductor pollicis brevis MEPs were obtained during routine motor mapping by neuronavigated transcranial magnetic stimulation in children with intractable, unihemispheric focal epilepsy. The primary motor cortex was stimulated bilaterally in all cases. Only data from patients without a lesion involving the corticospinal tract were included. We tested whether abductor pollicis brevis MEP latency varied as a function of seizure focus lateralization.

RESULTS

In the 17 patients who met the inclusion criteria, the mean latency of MEPs with amplitudes in the top and bottom quartiles was shorter in the epileptic hemisphere. Interhemispheric latency difference was greater in patients with lesional epilepsy than in those with nonlesional epilepsy (0.7 ± 0.4 vs. 0.1 ± 0.6 milliseconds, P = 0.02).

CONCLUSIONS

Motor evoked potential latency was shortened in the epileptic hemisphere of children with focal epilepsy.

N-acetylcysteine treatment mitigates loss of cortical parvalbumin-positive interneuron and perineuronal net integrity resulting from persistent oxidative stress in a rat TBI model

Traumatic brain injury (TBI) increases cerebral reactive oxygen species production, which leads to continuing secondary neuronal injury after the initial insult. Cortical parvalbumin-positive interneurons (PVIs; neurons responsible for maintaining cortical inhibitory tone) are particularly vulnerable to oxidative stress and are thus disproportionately affected by TBI. Systemic N-acetylcysteine (NAC) treatment may restore cerebral glutathione equilibrium, thus preventing post-traumatic cortical PVI loss. We therefore tested whether weeks-long post-traumatic NAC treatment mitigates cortical oxidative stress, and whether such treatment preserves PVI counts and related markers of PVI integrity and prevents pathologic electroencephalographic (EEG) changes, 3 and 6 weeks after fluid percussion injury in rats. We find that moderate TBI results in persistent oxidative stress for at least 6 weeks after injury and leads to the loss of PVIs and the perineuronal net (PNN) that surrounds them as well as of per-cell parvalbumin expression. Prolonged post-TBI NAC treatment normalizes the cortical redox state, mitigates PVI and PNN loss, and - in surviving PVIs - increases per-cell parvalbumin expression. NAC treatment also preserves normal spectral EEG measures after TBI. We cautiously conclude that weeks-long NAC treatment after TBI may be a practical and well-tolerated treatment strategy to preserve cortical inhibitory tone post-TBI.

Assessing the mechanisms of brain plasticity by transcranial magnetic stimulation

Transcranial magnetic stimulation (TMS) is a non-invasive technique for focal brain stimulation based on electromagnetic induction where a fluctuating magnetic field induces a small intracranial electric current in the brain. For more than 35 years, TMS has shown promise in the diagnosis and treatment of neurological and psychiatric disorders in adults. In this review, we provide a brief introduction to the TMS technique with a focus on repetitive TMS (rTMS) protocols, particularly theta-burst stimulation (TBS), and relevant rTMS-derived metrics of brain plasticity. We then discuss the TMS-EEG technique, the use of neuronavigation in TMS, the neural substrate of TBS measures of plasticity, the inter- and intraindividual variability of those measures, effects of age and genetic factors on TBS aftereffects, and then summarize alterations of TMS-TBS measures of plasticity in major neurological and psychiatric disorders including autism spectrum disorder, schizophrenia, depression, traumatic brain injury, Alzheimer's disease, and diabetes. Finally, we discuss the translational studies of TMS-TBS measures of plasticity and their therapeutic implications.

Discrepant expressive language lateralization in children and adolescents with epilepsy

Neuronavigated transcranial magnetic stimulation (nTMS) has emerged as a presurgical language mapping tool distinct from the widely used functional magnetic resonance imaging (fMRI). We report fMRI and nTMS language-mapping results in 19 pediatric-epilepsy patients and compare those to definitive testing by electrical cortical stimulation, Wada test, and/or neuropsychological testing. Most discordant results occurred when fMRI found right-hemispheric language. In those cases, when nTMS showed left-hemispheric or bilateral language representation, left-hemispheric language was confirmed by definitive testing. Therefore, we propose nTMS should be considered for pediatric presurgical language-mapping when fMRI shows right-hemispheric language, with nTMS results superseding fMRI results in those scenarios.

Biomarkers Obtained by Transcranial Magnetic Stimulation in Neurodevelopmental Disorders

SUMMARY

Transcranial magnetic stimulation (TMS) is a method for focal brain stimulation that is based on the principle of electromagnetic induction where small intracranial electric currents are generated by a powerful fluctuating magnetic field. Over the past three decades, TMS has shown promise in the diagnosis, monitoring, and treatment of neurological and psychiatric disorders in adults. However, the use of TMS in children has been more limited. We provide a brief introduction to the TMS technique; common TMS protocols including single-pulse TMS, paired-pulse TMS, paired associative stimulation, and repetitive TMS; and relevant TMS-derived neurophysiological measurements including resting and active motor threshold, cortical silent period, paired-pulse TMS measures of intracortical inhibition and facilitation, and plasticity metrics after repetitive TMS. We then discuss the biomarker applications of TMS in a few representative neurodevelopmental disorders including autism spectrum disorder, fragile X syndrome, attention-deficit hyperactivity disorder, Tourette syndrome, and developmental stuttering.

Large-scale analysis of interindividual variability in single and paired-pulse TMS data

OBJECTIVE

This study brought together over 60 transcranial magnetic stimulation (TMS) researchers to create the largest known sample of individual participant single and paired-pulse TMS data to date, enabling a more comprehensive evaluation of factors driving response variability.

METHODS

Authors of previously published studies were contacted and asked to share deidentified individual TMS data. Mixed-effects regression investigated a range of individual and study level variables for their contribution to variability in response to single and paired-pulse TMS data.

RESULTS

687 healthy participant's data were pooled across 35 studies. Target muscle, pulse waveform, neuronavigation use, and TMS machine significantly predicted an individual's single-pulse TMS amplitude. Baseline motor evoked potential amplitude, motor cortex hemisphere, and motor threshold (MT) significantly predicted short-interval intracortical inhibition response. Baseline motor evoked potential amplitude, test stimulus intensity, interstimulus interval, and MT significantly predicted intracortical facilitation response. Age, hemisphere, and TMS machine significantly predicted MT.

CONCLUSIONS

This large-scale analysis has identified a number of factors influencing participants' responses to single and paired-pulse TMS. We provide specific recommendations to minimise interindividual variability in single and paired-pulse TMS data.

SIGNIFICANCE

This study has used large-scale analyses to give clarity to factors driving variance in TMS data. We hope that this ongoing collaborative approach will increase standardisation of methods and thus the utility of single and paired-pulse TMS.

Modulation of motor cortical excitability by continuous theta-burst stimulation in adults with autism spectrum disorder

OBJECTIVE

To test whether change in motor evoked potential (ΔMEP) induced by continuous theta-burst stimulation (cTBS) of motor cortex (M1) distinguishes adults with autism spectrum disorder (ASD) from neurotypicals, and to explore the contribution of two common polymorphisms related to neuroplasticity.

METHODS

44 adult neurotypical (NT) participants (age 21-65, 34 males) and 19 adults with ASD (age 21-58, 17 males) prospectively underwent M1 cTBS. Their data were combined with previously obtained results from 35 NT and 35 ASD adults.

RESULTS

ΔMEP at 15 minutes post-cTBS (T15) was a significant predictor of diagnosis (p = 0.04) in the present sample (n=63). T15 remained a significant predictor in a larger sample (n=91) and when partially imputed based on T10-T20 from a yet-greater sample (N=133). T15 also remained a significant predictor of diagnosis among brain-derived neurotrophic factor (BDNF) Met+ and apolipoprotein E (APOE) ε4- subjects (p's < 0.05), but not among Met- or ε4+ subjects (p's > 0.19).

CONCLUSIONS

ΔMEP at T15 post-cTBS is a significant biomarker for adults with ASD, and its utility is modulated by BDNF and APOE polymorphisms.

SIGNIFICANCE

M1 cTBS response is a physiologic biomarker for adults with ASD in large samples, and controlling for BDNF and APOE polymorphisms can improve its diagnostic utility.

Reproducibility of cortical response modulation induced by intermittent and continuous theta-burst stimulation of the human motor cortex

Background:

Over the past decade, the number of experimental and clinical studies using theta-burststimulation (TBS) protocols of transcranial magnetic stimulation (TMS) to modulate brain activity has risen substantially. The use of TBS is motivated by the assumption that these protocols can reliably and lastingly modulate cortical excitability despite their short duration and low number of stimuli. However, this assumption, and thus the experimental validity of studies using TBS, is challenged by recent work showing large inter- and intra-subject variability in response to TBS protocols.

Objectives:

To date, the reproducibility of TBS effects in humans has been exclusively assessed with motor evoked potentials (MEPs), which provide an indirect and limited measure of cortical excitability. Here we combined TMS with electroencephalography (TMS-EEG) and report the first comprehensive investigation of (1) direct TMS-evoked cortical responses to intermittent (iTBS) and continuous TBS (cTBS) of the human motor cortex, and (2) reproducibility of both iTBS- and cTBS-induced cortical response modulation against a robust sham control across repeat visits with commonly used cortical responsivity metrics.

Results:

We show that although single pulse TMS generates stable and reproducible cortical responses across visits, the modulatory effects of TBS vary substantially both between and within individuals. Overall, at the group level, most measures of the iTBS and cTBS-induced effects were not significantly different from sham-TBS. Most importantly, none of the significant TBS-induced effects observed in visit1 were reproduced in visit-2.

Conclusions:

Our findings suggest that the generally accepted mechanisms of TBS-induced neuromodulation, i.e. through changes in cortical excitability, may not be accurate. Future research is needed to determine the mechanisms underlying the established therapeutic effects of TBS in neuropsychiatry and examine reproducibility of TBS-induced neuromodulation through oscillatory response dynamics.

Personality in Autism Spectrum Disorder: Associations With Face Memory Deficit and Theory of Mind

OBJECTIVE

To examine the personality profiles of adults with autism spectrum disorder (ASD) using a standard personality assessment and to investigate the association between personality, ASD-related face memory deficit (FMD), and theory of mind (ToM). In a broader context, to examine whether there are distinct clinical phenotypes in the ASD population that have implications for personality development and treatment.

METHOD

Fifty-five adults with ASD and 22 neurotypical (NT) adults underwent a battery of neuropsychological tests, including measures of personality, face memory, and ToM. We compared ASD and NT groups in terms of their Personality Assessment Inventory (PAI) profiles. Additional analyses focused on the association between specific PAI scales and FMD. Performance on the Eyes Test was compared across groups and was examined in relation to FMD.

RESULTS

Adults with ASD demonstrated significant elevations on several PAI scales compared with NT adults. The presence of FMD was associated with differing PAI profiles among the ASD adults. The ASD adults with FMD scored significantly higher on scales that are sensitive to positive impression management and treatment rejection and significantly lower on scales that are sensitive to borderline personality, anxiety, depression, schizophrenia, and stress. There was a significant association between performance on the Eyes Test and FMD in the ASD group.

CONCLUSION

Adults with ASD have a unique personality profile. Further, ASD adults with FMD have reduced insight into their difficulties with emotional processing and may not be as sensitive as ASD adults without FMD to the emotions of others.

Large-scale analysis of interindividual variability in theta-burst stimulation data: Results from the 'Big TMS Data Collaboration'

BACKGROUND

Many studies have attempted to identify the sources of interindividual variability in response to theta-burst stimulation (TBS). However, these studies have been limited by small sample sizes, leading to conflicting results.

OBJECTIVE/HYPOTHESIS

This study brought together over 60 TMS researchers to form the 'Big TMS Data Collaboration', and create the largest known sample of individual participant TBS data to date. The goal was to enable a more comprehensive evaluation of factors driving TBS response variability.

METHODS

118 corresponding authors of TMS studies were emailed and asked to provide deidentified individual TMS data. Mixed-effects regression investigated a range of individual and study level variables for their contribution to iTBS and cTBS response variability.

RESULTS

430 healthy participants' TBS data was pooled across 22 studies (mean age = 41.9; range = 17-82; females = 217). Baseline MEP amplitude, age, target muscle, and time of day significantly predicted iTBS-induced plasticity. Baseline MEP amplitude and timepoint after TBS significantly predicted cTBS-induced plasticity.

CONCLUSIONS

This is the largest known study of interindividual variability in TBS. Our findings indicate that a significant portion of variability can be attributed to the methods used to measure the modulatory effects of TBS. We provide specific methodological recommendations in order to control and mitigate these sources of variability.

Targeting Gamma-Related Pathophysiology in Autism Spectrum Disorder Using Transcranial Electrical Stimulation: Opportunities and Challenges

A range of scalp electroencephalogram (EEG) abnormalities correlates with the core symptoms of autism spectrum disorder (ASD). Among these are alterations of brain oscillations in the gamma-frequency EEG band in adults and children with ASD, whose origin has been linked to dysfunctions of inhibitory interneuron signaling. While therapeutic interventions aimed to modulate gamma oscillations are being tested for neuropsychiatric disorders such as schizophrenia, Alzheimer's disease, and frontotemporal dementia, the prospects for therapeutic gamma modulation in ASD have not been extensively studied. Accordingly, we discuss gamma-related alterations in the setting of ASD pathophysiology, as well as potential interventions that can enhance gamma oscillations in patients with ASD. Ultimately, we argue that transcranial electrical stimulation modalities capable of entraining gamma oscillations, and thereby potentially modulating inhibitory interneuron circuitry, are promising methods to study and mitigate gamma alterations in ASD. Autism Res 2020, 13: 1051-1071. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Brain functions are mediated by various oscillatory waves of neuronal activity, ranging in amplitude and frequency. In certain neuropsychiatric disorders, such as schizophrenia and Alzheimer's disease, reduced high-frequency oscillations in the "gamma" band have been observed, and therapeutic interventions to enhance such activity are being explored. Here, we review and comment on evidence of reduced gamma activity in ASD, arguing that modalities used in other disorders may benefit individuals with ASD as well.

Continuous Theta-Burst Stimulation in Children With High-Functioning Autism Spectrum Disorder and Typically Developing Children

Objectives: A neurophysiologic biomarker for autism spectrum disorder (ASD) is highly desirable and can improve diagnosis, monitoring, and assessment of therapeutic response among children with ASD. We investigated the utility of continuous theta-burst stimulation (cTBS) applied to the motor cortex (M1) as a biomarker for children and adolescents with high-functioning (HF) ASD compared to their age- and gender-matched typically developing (TD) controls. We also compared the developmental trajectory of long-term depression- (LTD-) like plasticity in the two groups. Finally, we explored the influence of a common brain-derived neurotrophic factor (BDNF) polymorphism on cTBS aftereffects in a subset of the ASD group. Methods: Twenty-nine children and adolescents (age range 10-16) in ASD (n = 11) and TD (n = 18) groups underwent M1 cTBS. Changes in MEP amplitude at 5-60 min post-cTBS and their cumulative measures in each group were calculated. We also assessed the relationship between age and maximum cTBS-induced MEP suppression (ΔMEP_Max) in each group. Finally, we compared cTBS aftereffects in BDNF Val/Val (n = 4) and Val/Met (n = 4) ASD participants. Results: Cumulative cTBS aftereffects were significantly more facilitatory in the ASD group than in the TD group (P _FDR's < 0.03). ΔMEP_Max was negatively correlated with age in the ASD group (r = -0.67, P = 0.025), but not in the TD group (r = -0.12, P = 0.65). Cumulative cTBS aftereffects were not significantly different between the two BDNF subgroups (P-values > 0.18). Conclusions: The results support the utility of cTBS measures of cortical plasticity as a biomarker for children and adolescents with HF-ASD and an aberrant developmental trajectory of LTD-like plasticity in ASD.

Aftereffects of Intermittent Theta-Burst Stimulation in Adjacent, Non-Target Muscles

To assess motor cortex neurophysiology, including the mechanisms of neuroplasticity, transcranial magnetic stimulation (TMS) is typically applied to the motor "hotspot"- the optimal site for inducing a twitch in a given target muscle. It is known that the effects of suprathreshold repetitive TMS (rTMS) spread along functional connections beyond the specific cortical stimulation target, and yet, it is unknown whether the aftereffects of subthreshold intermittent theta-burst stimulation (iTBS), an ultra-high frequency patterned rTMS protocol, extend beyond the targeted muscle. We investigated whether and to what extent iTBS induces changes in the cortical output to other intrinsic hand muscles with adjacent cortical representation to the target. Sixteen healthy adults underwent neuronavigated TMS-iTBS targeting the first dorsal interosseus (FDI) hotspot. Proportion of motor evoked potentials (MEPs) at the resting motor threshold (RMT), baseline MEP amplitude, and iTBS-induced changes in MEP amplitude were compared between FDI, abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles. MEP amplitudes recorded from the three muscles at RMT and suprathreshold intensities indicated the chosen hotspots were relatively selective for FDI. Nevertheless, iTBS induced significant facilitation of MEPs recorded from both FDI and APB, but not ADM. Surprisingly, the MEP modulation was greater in APB, even when controlling for the baseline MEP amplitude. These results indicate that iTBS modulation of cortico-spinal excitability extends beyond the representation of the targeted muscle. Results have implications both for how iTBS may be used in clinical treatment and for the safety guidelines for the application of iTBS.

Test-Retest Reliability of the Effects of Continuous Theta-Burst Stimulation

OBJECTIVES

The utility of continuous theta-burst stimulation (cTBS) as index of cortical plasticity is limited by inadequate characterization of its test-retest reliability. We thus evaluated the reliability of cTBS aftereffects, and explored the roles of age and common single-nucleotide polymorphisms in the brain-derived neurotrophic factor (BDNF) and apolipoprotein E (APOE) genes.

METHODS

Twenty-eight healthy adults (age range 21-65) underwent two identical cTBS sessions (median interval = 9.5 days) targeting the motor cortex. Intraclass correlation coefficients (ICCs) of the log-transformed, baseline-corrected amplitude of motor evoked potentials (ΔMEP) at 5-60 min post-cTBS (T5-T60) were calculated. Adjusted effect sizes for cTBS aftereffects were then calculated by taking into account the reliability of each cTBS measure.

RESULTS

ΔMEP at T50 was the most-reliable cTBS measure in the whole sample (ICC = 0.53). Area under-the-curve (AUC) of ΔMEPs was most reliable when calculated over the full 60 min post-cTBS (ICC = 0.40). cTBS measures were substantially more reliable in younger participants (< 35 years) and in those with BDNF Val66Val and APOE ε4- genotypes.

CONCLUSION

cTBS aftereffects are most reliable when assessed 50 min post-cTBS, or when cumulative ΔMEP measures are calculated over 30-60 min post-cTBS. Reliability of cTBS aftereffects is influenced by age, and BDNF and APOE polymorphisms. Reliability coefficients are used to adjust effect-size calculations for interpretation and planning of cTBS studies.

Effective coverage as a new approach to health system performance assessment: a scoping review

Background

Delivering interventions is the main task of health systems whose accurate measurement is an essential input into tracking performance. Recently, the concept of effective coverage was introduced by World Health Organization to incorporate into health system performance assessment. The aim of present scoping review was mapping the key elements and steps of effective coverage assessment in practical efforts including kinds of interventions, criteria for selecting them and the need, use and quality estimation approaches and strategies of each intervention.

Methods

We conducted a scoping review of health system/program assessments which assessed effective coverage till May 2017. Seven databases were systematically searched with no time and language restriction through applying combined keyword of “effective coverage”.

Results

Eighteen studies contributed findings on monitoring effective coverage of health interventions and they all were included in the review. Only 4 contributed findings on health system and the others were related to specific intervention(s) assessment. The interventions monitored by effective coverage were mainly in child health, prenatal and antenatal care and delivery, and chronic conditions areas. Potential impact on the burden of disease, leading causes of mortality and morbidity, and high occurrence and prevalence rate were among the main intervention selection criteria. Availability of data was the critical prerequisite, especially, in all of the studies applied ex post approach in estimating effective coverage. Estimation based on a norm, self- reporting from surveys and biomarkers were the main strategies and methods of need, utilization and quality measurement, respectively.

Conclusions

More studies are needed to contribute to the ongoing improvement in the development of effective coverage concept and increasing practical efforts, especially through defining prospective approaches and strategies into estimation of composite measures based on the effective coverage framework. Also, further attention needs to be paid to quality measures of effective coverage in a manner that better conceptualizes and measures the connection between coverage rates and interventions’ effectiveness. At the administrative system level, more innovation is needed to develop data systems in order to enhance capacity of routine health service information.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3692-7) contains supplementary material, which is available to authorized users.

Age-related differences in default-mode network connectivity in response to intermittent theta-burst stimulation and its relationships with maintained cognition and brain integrity in healthy aging

The default-mode network (DMN) is affected by advancing age, where particularly long-range connectivity has been consistently reported to be reduced as compared to young individuals. We examined whether there were any differences in the effects of intermittent theta-burst stimulation (iTBS) in DMN connectivity between younger and older adults, its associations with cognition and brain integrity, as well as with long-term cognitive status. Twenty-four younger and 27 cognitively normal older adults were randomly assigned to receive real or sham iTBS over the left inferior parietal lobule between two resting-state functional magnetic resonance imaging (rs-fMRI) acquisitions. Three years later, those older adults who had received real iTBS underwent a cognitive follow-up assessment. Among the younger adults, functional connectivity increased following iTBS in distal DMN areas from the stimulation site. In contrast, older adults exhibited increases in connectivity following iTBS in proximal DMN regions. Moreover, older adults with functional responses to iTBS resembling those of the younger participants exhibited greater brain integrity and higher cognitive performance at baseline and at the 3-year follow-up, along with less cognitive decline. Finally, we observed that 'young-like' functional responses to iTBS were also related to the educational background attained amongst older adults. The present study reveals that functional responses of the DMN to iTBS are modulated by age. Furthermore, combining iTBS and rs-fMRI in older adults may allow characterizing distinctive cognitive profiles in aging and its progression, probably reflecting network plasticity systems that may entail a neurobiological substrate of cognitive reserve.

Stewardship as a Fundamental Challenge in Strategic Purchasing of Health Services: A Case Study of Iran

OBJECTIVE

To understand the stewardship challenges in strategic purchasing of health care in Iran's health system from the viewpoints of experts, policy makers, and decision makers.

STUDY DESIGN

This was a qualitative study.

METHODS

Researchers used interviews and FGDs for collecting and framework analysis for analyzing data.

RESULTS

Stewardship challenges were classified into three themes and nine subthemes. A lack of management information systems, a lack of enforcement for rules and laws, a lack of stewardship units, and the conflict of interest between the Ministry of Health and insurers as care purchasers in the health system are among the main challenges identified in the implementation of the strategic purchasing of health care in Iran.

CONCLUSION

A strong stewardship is needed for implementing strategic purchasing of health care, which requires participation of all stakeholders.

Modelling the prevalence of diabetes mellitus risk factors based on artificial neural network and multiple regression

Background

Type 2 diabetes mellitus (T2DM) is a metabolic disease with complex causes, manifestations, complications and management. Understanding the wide range of risk factors for T2DM can facilitate diagnosis, proper classification and cost-effective management of the disease.

Aims

To compare the power of an artificial neural network (ANN) and logistic regression in identifying T2DM risk factors.

Methods

This descriptive and analytical study was conducted in 2013. The study samples were all residents aged 15-64 years of rural and urban areas in East Azerbaijan, Islamic Republic of Iran, who consented to participate (n = 990). The latest data available were collected from the Noncommunicable Disease Surveillance System of East Azerbaijan Province (2007). Data were analysed using SPSS version 19.

Results

Based on multiple logistic regression, age, family history of T2DM and residence were the most important risk factors for T2DM. Based on ANN, age, body mass index and current smoking were most important. To test for generalization, ANN and logistic regression were evaluated using the area under the receiver operating characteristic curve (AUC). The AUC was 0.726 (SE = 0.025) and 0.717 (SE = 0.026) for logistic regression and ANN, respectively (P < 0.001).

Conclusions

The logistic regression model is better than ANN and it is clinically more comprehensible.

The Effects of Waveform and Current Direction on the Efficacy and Test-Retest Reliability of Transcranial Magnetic Stimulation

The pulse waveform and current direction of transcranial magnetic stimulation (TMS) influence its interactions with the neural substrate; however, their role in the efficacy and reliability of single- and paired-pulse TMS measures is not fully understood. We investigated how pulse waveform and current direction affect the efficacy and test-retest reliability of navigated, single- and paired-pulse TMS measures. 23 healthy adults (aged 18-35 years) completed two identical TMS sessions, assessing resting motor threshold (RMT), motor-evoked potentials (MEPs), cortical silent period (cSP), short- and long-interval intra-cortical inhibition (SICI and LICI), and intracortical facilitation (ICF) using either monophasic posterior-anterior (mono_PA; n = 9), monophasic anterior-posterior (mono_AP; n = 7), or biphasic (bi_AP-PA; n = 7) pulses. Averages of each TMS measure were compared across the three groups and intraclass correlation coefficients were calculated to assess test-retest reliability. RMT was the lowest and cSP was the longest with bi_AP-PA pulses, whereas MEP latency was the shortest with mono_PA pulses. SICI and LICI had the largest effect with mono_PA pulses, whereas only mono_AP and bi_AP-PA pulses resulted in significant ICF. MEP amplitude was more reliable with either mono_PA or mono_AP than with bi_AP-PA pulses. LICI was the most reliable with mono_AP pulses, whereas ICF was the most reliable with bi_AP-PA pulses. Waveform/current direction influenced RMT, MEP latency, cSP, SICI, LICI, and ICF, as well as the reliability of MEP amplitude, LICI, and ICF. These results show the importance of considering TMS pulse parameters for optimizing the efficacy and reliability of TMS neurophysiologic measures.

A Successful implementation of an idea to a nationally approved plan: Analyzing Iran's National Health Roadmap using the Kingdon model of policymaking

Introduction: Hospital beds, human resources, and medical equipment are the costliest elements in the health system and play an essential role at the time of treatment. In this paper, different phases of the NEDA 2026 project and its methodological approach were presented and its formulation process was analysed using the Kingdon model of policymaking. Methods: Iran Health Roadmap (NEDA 2026) project started in March 2016 and ended in March 2017. The main components of this project were hospital beds, clinical human resources, specialist personnel, capital medical equipment, laboratory facilities, emergency services, and service delivery model. Kingdon model of policymaking was used to evaluate NEDA 2026 development and implementation. In this study, all activities to accomplish each step in the Kingdon model was described. Results: The followings were done to accomplish the goals of each step: collecting experts' viewpoint (problem identification and definition), systematic review of the literature, analysis of previous experiences, stakeholder analysis, economic analysis, and feasibility study (solution appropriateness analysis), three-round Delphi survey (policy survey and scrutinization), and intersectoral and interasectoral agreement (policy legislation). Conclusion: In the provision of an efficient health service, various components affect each other and the desired outcome, so they need to be considered as parts of an integrated system in developing a roadmap for the health system. Thus, this study demonstrated the cooperation process at different levels of Iran's health system to formulate a roadmap to provide the necessary resources for the health sector for the next 10 years and to ensure its feasibility using the Kingdon policy framework.

Interindividual variability in response to continuous theta-burst stimulation in healthy adults

OBJECTIVE

We used complete-linkage cluster analysis to identify healthy subpopulations with distinct responses to continuous theta-burst stimulation (cTBS).

METHODS

21 healthy adults (age±SD, 36.9±15.2years) underwent cTBS of left motor cortex. Natural log-transformed motor evoked potentials (LnMEPs) at 5-50min post-cTBS (T5-T50) were calculated.

RESULTS

Two clusters were found; Group 1 (n=12) that showed significant MEP facilitation at T15, T20, and T50 (p's<0.006), and Group 2 (n=9) that showed significant suppression at T5-T15 (p's<0.022). LnMEPs at T10 and T40 were best predictors of, and together accounted for 80% of, cluster assignment. In an exploratory analysis, we examined the roles of brain-derived neurotrophic factor (BDNF) and apolipoprotein E (APOE) polymorphisms in the cTBS response. Val66Met participants showed greater facilitation at T10 than Val66Val participants (p=0.025). BDNF and cTBS intensity predicted 59% of interindividual variability in LnMEP at T10. APOE did not significantly affect LnMEPs at any time point (p's>0.32).

CONCLUSIONS

Data-driven cluster analysis can identify healthy subpopulations with distinct cTBS responses. T10 and T40 LnMEPs were best predictors of cluster assignment. T10 LnMEP was influenced by BDNF polymorphism and cTBS intensity.

SIGNIFICANCE

Healthy adults can be sorted into subpopulations with distinct cTBS responses that are influenced by genetics.

Reproducibility of Single-Pulse, Paired-Pulse, and Intermittent Theta-Burst TMS Measures in Healthy Aging, Type-2 Diabetes, and Alzheimer's Disease

Background: Transcranial magnetic stimulation (TMS) can be used to assess neurophysiology and the mechanisms of cortical brain plasticity in humans in vivo. As the use of these measures in specific populations (e.g., Alzheimer’s disease; AD) increases, it is critical to understand their reproducibility (i.e., test–retest reliability) in the populations of interest.

Objective: Reproducibility of TMS measures was evaluated in older adults, including healthy, AD, and Type-2 diabetes mellitus (T2DM) groups.

Methods: Participants received two identical neurophysiological assessments within a year including motor thresholds, baseline motor evoked potentials (MEPs), short- and long-interval intracortical inhibition (SICI, LICI) and intracortical facilitation (ICF), and MEP changes following intermittent theta-burst stimulation (iTBS). Cronbach’s α coefficients were calculated to assess reproducibility. Multiple linear regression analyses were used to investigate factors related to intraindividual variability.

Results: Reproducibility was highest for motor thresholds, followed by baseline MEPs, SICI and LICI, and was lowest for ICF and iTBS aftereffects. The AD group tended to show higher reproducibility than T2DM or controls. Intraindividual variability of baseline MEPs was related to age and variability of RMT, while the intraindividual variability in post-iTBS measures was related to baseline MEP variability, intervisit duration, and Brain-derived neurotrophic factor (BDNF) polymorphism.

Conclusion: Increased reproducibility in AD may reflect pathophysiological declines in the efficacy of neuroplastic mechanisms. Reproducibility of iTBS aftereffects can be improved by keeping baseline MEPs consistent, controlling for BDNF genotype, and waiting at least a week between visits.

Significance: These findings provide the first direct assessment of reproducibility of TMS measures in older clinical populations. Reproducibility coefficients may be used to adjust effect- and sample size calculations for future studies.

The effects of exercise on cognitive function and brain plasticity - a feasibility trial

BACKGROUND

Exercise-mediated cognitive improvements can be at least partly attributed to neuroplastic changes in the nervous system, and may be influenced by the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene. Transcranial magnetic stimulation (TMS) can be used to assess mechanisms of plasticity in humans noninvasively.

OBJECTIVES

To assess the feasibility of evaluating the effects of short-term regular exercise on cognitive performance, and to evaluate the relationship between these effects, TMS measures of plasticity, and BDNF Met carrier status in young healthy sedentary adults.

METHODS

Of the 19 participants who enrolled in the study, 14 sedentary adults (12 females, age mean±SD, 27±12.3 yr), with less than two sessions of physical exercise in the preceding 2 months, completed an aerobic exercise regimen including four 30-min daily sessions per week for 4 weeks (for a total of 16 sessions) delivered at 55-64% of age-predicted maximal heart rate. Prior to and following the exercise regimen, participants performed a neuropsychological test battery and an intermittent theta-burst TMS plasticity protocol.

RESULTS

All participants completed the various measures and adhered to the exercise regimen. There were no complications and the results obtained were reliable. The feasibility of the approach is thus well established. Between-group comparisons of pre-post change revealed trends toward increased performance on the Stroop and faster reaction times in the CPT detectability in the Val66Val subgroup (p = 0.07 and p = 0.08), and a reduction in TBS-induced modulation of TMS responses in Met carriers (p = 0.07).

CONCLUSION

Acute exercise interventions in sedentary adults can be meaningfully conducted along with cognitive and neurophysiologic measures to assess behavioral and neurobiological effects and assessment of BDNF polymorphism. TMS measures of plasticity can be used to evaluate the effects of exercise on brain plasticity, and relate them to neuropsychological measures of cognition.

Optimal number of pulses as outcome measures of neuronavigated transcranial magnetic stimulation

OBJECTIVE

Identify the optimal number of pulses necessary to achieve reliable measures of motor evoked potentials (MEPs) in transcranial magnetic stimulation (TMS) studies.

METHODS

Retrospective data was obtained from 54 healthy volunteers (30 men, mean age 61.7±13.1years) who as part of prior studies had completed three blocks of 30 consecutive TMS stimuli using neuronavigation. Data from four protocols were assessed: single-pulse TMS for measures of amplitude and latency of MEPs; paired-pulse TMS for short-interval intracortical inhibition (sICI) and intracortical facilitation (ICF); and single-pulse TMS to assess the effects of intermittent theta burst stimulation (iTBS). Two statistical methods were used: an internal consistency analysis and probability of inclusion in the 95% confidence interval (CI) around the mean MEPs amplitude.

RESULTS

For single-pulse TMS, the minimum number of pulses needed to achieve reliable amplitude and latency MEPs measures was 21 and 23, respectively. For paired-pulse TMS, the minimum number of pulses needed to achieve reliable sICI and ICF measures was 20 and 25, respectively. Finally, the minimum number of pulses needed to achieve reliable amplitude and latency MEPs measures after iTBS was 22 and 23, respectively.

CONCLUSIONS

This study provides guidelines regarding the minimum number of pulses needed to achieve reliable MEPs measurements in various study protocols using neuronavigated TMS.

SIGNIFICANCE

Results from this study have the potential to increase the reliability and quality of future neuronavigated TMS studies.

Escape from temporal-integration masking: the roles of visible persistence and input filtering

A brief target embedded in—and coterminating with—a noise mask is identified easily when the duration of the mask is long but not when it is short (Di Lollo, 1980; inverse-duration effect). Identification has been said to be mediated by the visible persistence of the target, which outlasted that of the mask. We tested an alternative account based on input filtering triggered by the onset and offset of the target, relative to those of the mask, without recourse to visible persistence. The results of Experiment 1 could not be explained wholly in terms of visible persistence but were entirely consistent with input filtering. Identification suffered in Experiment 2 when transient responses were attenuated by "ramping." In Experiment 3, accuracy improved gradually as a function of leading-mask duration. All results were consistent with a modified version of von Holst's (1954) hypothesis that a new stimulus (e.g., the present mask) establishes an input filter within the system. Any sudden onsets or offsets then lead to the perception of a new object only when they do not match the input filter, thus becoming segregated from the temporally leading stimulus.

An Innovative Method to Enhance the Modified DOTS for TB Patients

BACKGROUND

Nowadays establishing communication and educating patients to enhance their knowledge regarding disease and treatment process at home is one of the most important principles in providing patient care.

MATERIALS AND METHODS

A semi-experimental study was done on 57 patients with active pulmonary tuberculosis in two care groups namely professional - family mix directly observed treatment short- course (PFM-DOTS) and family based-DOTS (FB-DOTS). The patients were referred to the tuberculosis and lung diseases research center for diagnosis and treatment of pulmonary tuberculosis. Both the patient and a family supervisor were evaluated regarding their level of knowledge of the disease and the treatment regimen.

RESULTS

A significant difference between the degree of knowledge of groups of patients and the groups of family relatives before and after the intervention was indicated, with a higher increase in PFM-DOTS group than in F-B-DOTS group (P< 0.001). In PFM- DOTS group 100% of the patients, and in the FB-DOTS group 86.8% of the patients followed the recommended drug regimen (P<0.001).

CONCLUSION

According to the treatment recommendations by the World Health Organization (WHO) for appropriate implementation of DOTS project combating TB, it seems the PFM-DOTS implementation is a more suitable method with greater effects on correct care and treatment of tuberculosis patients.

The Effectiveness of Family-Based DOTS versus Professional-Family Mix DOTS in Treating Smears Positive Tuberculosis

BACKGROUND

The present study compared the effectiveness of Family-Based DOTS (FB-DOTS) versus Professional-Family Mix DOTS (PFM-DOTS) in smear positive tuberculosis (TB) patients.

METHODS

This semi-experimental study was performed in Tuberculosis and Lung Diseases Research Center of Tabriz in 2011-2012, among 57 TB patients recruited into either FB-DOTS or PFM-DOTS groups. At the baseline of the study, knowledge of both patients and their supervisors were assessed while at the end point, smear and culture of sputum, quality of life, knowledge and satisfaction of the patients along with the knowledge and satisfaction of their supervisors were assessed.

RESULTS

The difference for sputum smear negative (culture) was 16.2 (4.8%) and 7.7(6.9%) for the PFM-DOTS in comparison with FB DOTS by the end of the second and forth months of treatment, respectively. A significant difference was observed between the two groups in relation to knowledge, satisfaction (patients and supervisors) and all four domains of quality of life: physical health (P=0.036), psychological health (P<0.001), social relations (P=0.026) and environmental health (P<0.001).

CONCLUSION

The PFM-DOTS treatment strategy in which health experts follow the patients in their homes seems to be among most appropriate strategies in treating TB.

Challenges in developing health promoting schools' project: application of global traits in local realm

BACKGROUND

Despite the importance of student health and school hygiene as an aspect of the infrastructure of community health, few feasibility studies have been conducted on school health programs in developing countries. This study examined possible barriers to and challenges of such programs from the executive perspective in East Azerbaijan Province in Iran.

METHODS

This qualitative study used the content analysis approach to recognize barriers to and challenges of health promoting school program from the executive perspective. Fourteen experts were selected in the areas of children and adolescents and school health, physical education and school headmasters. Data were collected using semi-structured interviews and analyzed using the content analysis method.

RESULTS

Five themes were extracted as major barriers and challenges: 1. Intraand inter-sectorial collaboration; 2. Policy and rule formulation; 3. Infrastructure and capacity; 4. Human resources; 5. Community involvement.

CONCLUSION

The localized version of the current health promoting school program had major faults. If this program is considered to be a healthcare system priority, it should be revised to set effective policies for implementation and to sustain school health programs based on the capacities and objectives of each country.

Perception and expectation of iran neonatal transport expert regard to developing neonatal transport system in iran: a qualitative research

Introduction:

This study was aimed to reach expert's expectations of neonatal transport system for developing neonatal transport system in Iran.

Materials and Methods:

This is a qualitative study conducted by using focus group discussion (FGD) to present expert's perspectives and expectancy about neonatal transport system. Participants was selected from all experts and specialist about neonatal transport in Iran countryside. Finally 48 experts, participate in this study. To data collection 4 FGD were conducted, data were analyzed by content analyses. All subthemes were categorized in main themes according to conceptual relationship as an expert panels opinions. In order to comply with the ethical issues involved in the study was voluntary, also permission for the recording session were taken and confidentiality was also ensured.

Result:

According to FGD results, 11 themes and 90 subthemes were founded related to neonatal transport system, the main identified themes included: Aims, necessity and models of neonatal transport system, organizing the transport system, management and quality of instruments in the transport system, Neonatal transport system staff, Human resource management and issue related to human resources, conditions and requirements of neonatal transport system, facilitating factors in neonatal transport system, information management and communication system and weakness of neonatal transport system.

Conclusion:

Neonatal transport systems in different countries must adapted according to situation and component of each country have different strength and weakness and in implementing a system must attend to geographical conditions, financial ability and access to professionals, health system structure, facilities related to neonatal health care, antenatal services in regain, health care related, health care program about neonates and pregnant women and epidemiological status and mortality and morbidity in deferent locals and regains in countryside.

Advantages and disadvantages of different methods of hospitals' downsizing: a narrative systematic review

BACKGROUND

Hospitals as key actors in health systems face growing pres-sures especially cost cutting and search for costeffective ways to resources management. Downsizing is one of these ways. This study was conducted to identify advantages and disadvantages of different methods of hospital' downsizing.

METHODS

The search was conducted in databases of Medlib, SID, Pub Med, Science Direct and Google Scholar Meta search engine by keywords of Downsizing, Hospital Downsizing, Hospital Rightsizing, Hospital Restructuring, Staff Downsizing, Hospital Merging, Hospital Reorganization and the Persian equivalents. Resulted 815 articles were studied and refined step by step. Finally, 27 articles were selected for analysis.

RESULTS

Five hospital downsizing methods were identified during searching. These methods were reducing the number of employees and beds, outsourcing, integration of hospital units, and the combination of these methods. The most important benefits were cost reduction, increasing patient satisfaction, increasing home care and outpatient services. The most important disadvantage included reducing access, reducing the rate of hospital admissions and increasing employees' workload and dissatisfaction.

CONCLUSION

Each downsizing method has strengths and weaknesses. Using different methods of downsizing, according to circumstances and applying appropriate interventions after implementation, is necessary for promotion.

Tracking target and distractor processing in fixed-feature visual search: evidence from human electrophysiology

Salient distractors delay visual search for less salient targets in additional-singleton tasks, even when the features of the stimuli are fixed across trials. According to the salience-driven selection hypothesis, this delay is due to an initial attentional deployment to the distractor. Recent event-related potential (ERP) studies found no evidence for salience-driven selection in fixed-feature search, but the methods employed were not optimized to isolate distractor ERP components such as the N2pc and distractor positivity (PD; indices of selection and suppression, respectively). Here, we isolated target and distractor ERPs in two fixed-feature search experiments. Participants searched for a shape singleton in the presence of a more-salient color singleton (Experiment 1) or for a color singleton in the presence of a less-salient shape singleton (Experiment 2). The salient distractor did not elicit an N2pc, but it did elicit a PD on fast-response trials. Furthermore, distractors had no effect on the timing of the target N2pc. These results indicate that (a) the distractor was prevented from engaging the attentional mechanism associated with N2pc, (b) the distractor did not interrupt the deployment of attention to the target, and (c) competition for attention can be resolved by suppressing locations of irrelevant items on a salience-based priority map.

Prioritizing public- private partnership models for public hospitals of iran based on performance indicators

BACKGROUND

The present study was conducted to scrutinize Public- Private Partnership (PPP) models in public hospitals of different countries based on performance indicators in order to se-lect appropriated models for Iran hospitals.

METHODS

In this mixed (quantitative-qualitative) study, systematic review and expert panel has been done to identify varied models of PPP as well as performance indicators. In the second step we prioritized performance indicator and PPP models based on selected performance indicators by Analytical Hierarchy process (AHP) technique. The data were analyzed by Excel 2007 and Expert Choice11 software's.

RESULTS

In quality - effectiveness area, indicators like the rate of hospital infections (100%), hospital accidents prevalence rate (73%), pure rate of hospital mortality (63%), patient satisfaction percentage (53%), in accessibility equity area indicators such as average inpatient waiting time (100%) and average outpatient waiting time (74%), and in financial - efficiency area, indicators including average length of stay (100%), bed occupation ratio (99%), specific income to total cost ratio (97%) have been chosen to be the most key performance indicators. In the pri¬oritization of the PPP models clinical outsourcing, management, privatization, BOO (build, own, operate) and non-clinical outsourcing models, achieved high priority for various performance in¬dicator areas.

CONCLUSION

This study had been provided the most common PPP options in the field of public hospitals and had gathered suitable evidences from experts for choosing appropriate PPP option for public hospitals. Effect of private sector presence in public hospital performance, based on which PPP options undertaken, will be different.