Dichotomous Classifications Research Articles

Más allá del partido: empresarios, tecnócratas y agentes políticos en los gabinetes ministeriales dominicanos

Objective/context: This study analyzes the partisan connections of individuals who attain ministerial positions in the Dominican Republic, identifying the influence of political parties, economic elites, and technical profiles in the formation of presidential cabinets. Methodology: Following the typology proposed by Camerlo and Castaldo, we categorize the partisan profiles of the governments of the Dominican Liberation Party (PLD) from 2016 to 2020, and the Modern Revolutionary Party (PRM) from 2020 to 2024. This aims to characterize their internal variation in scenarios of low formal institutionalization that are not captured by traditional dichotomous classifications. Conclusions: The heterogeneity in the influence of party leadership illustrates how Dominican parties diverge from the party government model. The predominance of non-partisan profiles in the core planning ministries, along with the presence of politician- businessmen in the rest of the portfolios, highlights the risk of political capture in this country. Originality: These results call into question the influence of the party as the center of power in dominant presidentialism.

Do uncontrolled processes contribute to evaluative learning? Insights from a new two-US process dissociation procedure and ambivalence measures.

The contribution of uncontrolled processes to evaluative learning has been examined in evaluative conditioning procedures by comparing evaluations of conditioned stimuli between tasks or within tasks but between learning instruction conditions. In the present research, we introduced a new procedure that keeps both tasks and instructions constant. In addition, we introduced ambivalence measures to address this uncontrollability question. The new procedure involves forming an impression of conditioned stimuli based on their pairing with one unconditioned stimulus while attending but discarding the influence of another unconditioned stimulus holding the same (congruent trials) versus a different (incongruent trials) valence. When the to-be-used and to-be-discarded unconditioned stimuli share the same (vs. a different) valence, controlled and uncontrolled processes should support the same (vs. opposite) responses. We used this approach in two preregistered experiments (Ntotal = 467) using dichotomous evaluative classifications (Experiments 1 and 2), evaluative ratings, and two measures of attitudinal ambivalence: mouse trajectories and felt ambivalence (Experiment 2). While we failed to find evidence for uncontrolled processes in evaluative classification frequencies separately in Experiments 1 and 2, analyses of aggregated classification frequencies across Experiments 1 and 2 suggested a small contribution of uncontrolled processes. In addition, we found larger felt ambivalence for incongruent than congruent trials. Overall, the present findings are mixed but support the possibility of a contribution of uncontrolled processes to evaluative learning, even when control is applied to a focal stimulus and additional influences come from a to-be-disregarded stimulus.

Incorporating algorithmic uncertainty into a clinical machine deep learning algorithm for urgent head CTs.

Machine learning (ML) algorithms to detect critical findings on head CTs may expedite patient management. Most ML algorithms for diagnostic imaging analysis utilize dichotomous classifications to determine whether a specific abnormality is present. However, imaging findings may be indeterminate, and algorithmic inferences may have substantial uncertainty. We incorporated awareness of uncertainty into an ML algorithm that detects intracranial hemorrhage or other urgent intracranial abnormalities and evaluated prospectively identified, 1000 consecutive noncontrast head CTs assigned to Emergency Department Neuroradiology for interpretation. The algorithm classified the scans into high (IC+) and low (IC-) probabilities for intracranial hemorrhage or other urgent abnormalities. All other cases were designated as No Prediction (NP) by the algorithm. The positive predictive value for IC+ cases (N = 103) was 0.91 (CI: 0.84-0.96), and the negative predictive value for IC- cases (N = 729) was 0.94 (0.91-0.96). Admission, neurosurgical intervention, and 30-day mortality rates for IC+ was 75% (63-84), 35% (24-47), and 10% (4-20), compared to 43% (40-47), 4% (3-6), and 3% (2-5) for IC-. There were 168 NP cases, of which 32% had intracranial hemorrhage or other urgent abnormalities, 31% had artifacts and postoperative changes, and 29% had no abnormalities. An ML algorithm incorporating uncertainty classified most head CTs into clinically relevant groups with high predictive values and may help accelerate the management of patients with intracranial hemorrhage or other urgent intracranial abnormalities.

INTERFERENTI ENDOCRINI: VALUTAZIONE DEL RISCHIO DI EFFETTI SULLA RIPRODUZIONE E SVILUPPO EMBRIONALE

The definition of endocrine disruptor includes those compounds that cause adverse effects by a mechanism of action involving one, or rarely, more components of the complex of hormones that regulate the life of a higher organism. This classification differs from other toxicological classifications because it considers a mode of action rather than an effect. Like all quality classifications, and not based on quantitative data such as the dose-response relationship and the estimation of exposure, typical of risk assessment, it is not very useful for the management of substances so classified. In fact, decisions based on dichotomous classifications, interfering/non-interfering, can only be dichotomous, approved/non-approved use. Toxicity studies performed on the experimental animal identify the apical effects, including those that can result from a mechanism involving the hormonal system. On the basis of the dose response relationship for these effects, it is possible to identify the dose without effect (No Observable Adverse Effect Level, NOAEL, generally expressed in mg/kg body weight) and from this, dividing by appropriate factors, called safety or uncertainty factors, the exposure limit is defined (for example the Acceptable Daily Intake, ADI). If effects possibly related to endocrine disruption are observed, specific in vitro, in vivo or even computational studies may be conducted to understand the mechanism underlying the observed effect and, possibly, to a more accurate definition of the dose response relationship. Therefore, the simple classification as endocrine disruptor should not preclude the quantitative approach to risk assessment, and the classification should not be use alone to take risk management decisions.

Observational Measurement of Attachment in Toddlers with Disruptive Behavior Using the Strange Situation Procedure and Attachment Q-Set

Child-caregiver attachment is important for healthy child development and is often targeted by relationship-based parenting interventions for young children. To assess the efficacy of these interventions, attachment must be measured accurately at multiple timepoints across the toddler years, coinciding with different stages of development. Among others, populations referred for treatment of externalizing behavior problems are of particular importance here. The Strange Situation Procedure (SSP) and Attachment Q-Set (AQS) are empirically-validated measures of child-caregiver attachment with unique strengths and weaknesses. However, there are no published investigations on concurrent relations between the two measures using clinically-referred, mental health populations. Previous research has reached mixed conclusions when comparing the observer-report AQS and SSP for children from other populations and based on child age. Using a clinical sample of 69 Australian mother-toddler dyads referred for disruptive behavior problems, this study examined associations among behavior problems, dichotomous SSP classifications of security and organization, AQS security scores, and child age. In line with hypotheses, a small to medium negative correlation between AQS security and externalizing behavior was found. Unexpectedly, no significant associations were found between dichotomous SSP security and externalizing behavior nor between SSP organization and externalizing behavior. Although AQS security scores and SSP classifications were not significantly correlated for the sample as a whole, there was a moderate positive correlation between the two measures for children aged 19–25 months. Implications for future research measuring attachment in this population, with relevance for relationship-based parenting intervention outcome studies are discussed.

The diagnostic accuracy of MRI in determining the relations between paraclinoid aneurysms and the cavernous sinus

PurposeThe location of paraclinoid aneurysms is determinant for evaluation of its intradural compartment and risk of SAH after rupture. Advanced MRI techniques have provided clear visualization of the distal dural ring (DDR) to determine whether an aneurysm is intracavernous, transitional or intradural for decision-making. We analyzed the diagnostic accuracy of MRI in predicting whether a paraclinoid aneurysm is intracavernous, transitional or intradural.MethodsWe conducted a prospective cohort between January 2014 and December 2018. Patients with paraclinoid aneurysms underwent 3D fast spin-echo MRI sequence before surgical treatment. The DDR was the landmark for MRI characterization of the aneurysms as follow: (i) Intradural; (ii) Transitional; and (iii) Intracavernous. The MRI sensitivity, specificity, positive and negative likelihood ratios were determined compared to the intraoperative findings. We also evaluated the intertechnique agreement using the Cohen’s kappa coefficient (κ) for dichotomous classifications (cavernous vs non-cavernous).ResultsTwenty patients were included in the cohort. The accuracy of MRI showed a sensitivity of 86.7% (95%CI:59.5–98.3) and specificity of 90.0% (95%CI:55.5–99.8). Analyzing only patients without history of SAH, accuracy test improved with a sensitivity of 92.3% (95%CI:63.9–99.8) and specificity reached 100% (95%CI: 63–100). Values of Cohen’s kappa (κ), intertechnique agreement was considered substantial for dichotomous classifications (κ = 0.754; p < 0.001). For patients without previous SAH, intertechnique agreement was even more coincident for the dichotomous classification (κ = 0.901; p < 0.001).Conclusion3D fast spin-echo MRI sequence is a reliable and useful technique for determining the location of paraclinoid aneurysms in relation to the cavernous sinus, particularly for patients with no history of SAH.

Quantifying prediction of pathogenicity for within-codon concordance (PM5) using 7541 functional classifications of BRCA1 and MSH2 missense variants

PurposeConditions and thresholds applied for evidence weighting of within-codon concordance (PM5) for pathogenicity vary widely between laboratories and expert groups. Because of the sparseness of available clinical classifications, there is little evidence for variation in practice. MethodsWe used as a truthset 7541 dichotomous functional classifications of BRCA1 and MSH2, spanning 311 codons of BRCA1 and 918 codons of MSH2, generated from large-scale functional assays that have been shown to correlate excellently with clinical classifications. We assessed PM5 at 5 stringencies with incorporation of 8 in silico tools. For each analysis, we quantified a positive likelihood ratio (pLR, true positive rate/false positive rate), the predictive value of PM5-lookup in ClinVar compared with the functional truthset. ResultspLR was 16.3 (10.6-24.9) for variants for which there was exactly 1 additional colocated deleterious variant on ClinVar, and the variant under examination was equally or more damaging when analyzed using BLOSUM62. pLR was 71.5 (37.8-135.3) for variants for which there were 2 or more colocated deleterious ClinVar variants, and the variant under examination was equally or more damaging than at least 1 colocated variant when analyzed using BLOSUM62. ConclusionThese analyses support the graded use of PM5, with potential to use it at higher evidence weighting where more stringent criteria are met.

A framework for investigating the land degradation neutrality – Disaster risk reduction nexus at the sub-national scales

Specific guidelines are needed to overcome dichotomous classifications of lands into degraded or not for leveraging the Land Degradation Neutrality (LDN) concept. Overlooking degrading lands or those at risk of degradation can block LDN. Therefore, this paper proposes a detailed land classification method, and complements LDN with an indicator α (wildfires, landslides and insights on aridity). Indicator α taps the rarely studied LDN-natural hazards nexus. For separating degrading, degraded and non-degraded lands, twelve categories were defined, and indicators were then established. Subsequently, a land potential-hazard informed LDN intervention was planned. These methods target sub-national scales via the Lebanese/Mediterranean Aley district. Findings first revealed that Aley's land cover developed without considering land potential or hazard potentiality. Second, land status categories are distributed as 65% stable (of which 20.18 are lightly used), 8.14% non-degraded (adequately used, recovered and improving), 13.67% degraded, and 13.13% at risk of degradation. However, the district risks shifting towards less healthy land states due to unplanned development and natural hazards inconsideration. Accordingly, the LDN intervention targeted the stable/lightly used, at risk of degradation-/lightly used, overused and lightly used lands for optimization. This approach shifted 33.33% of Aley to adequately used lands, increasing the latter from 8.05% to 41.38%.

Intra- and Interobserver Agreement during the Assessment of the Different Stages of Root Development Using 4 Radiographic Classifications

IntroductionThis study analyzed intra- and interobserver agreements during radiographic assessment of the different stages of root development using the dichotomous, Moorrees, Demirjian, and Cvek classifications, as well as the effect of the observer’s level of experience on the result. MethodsTwo hundred eighty-five digital periapical radiographs were examined via visual inspection by 3 experienced and 3 nonexperienced observers (n = 6) under strict technological and viewing conditions. After observer calibration, determination of the presence or absence of an open apex and the assignment of a root development stage according to the different subdivisions of the 4 indexes were performed. This evaluation was carried out by each observer in duplicate in the first round (n = 8) and repeated in the second round (n = 8). The 16 examinations performed by each observer (N = 96) were analyzed to determine the percentage of concordance followed by intraobserver, interobserver, and global observer agreement using the kappa coefficient and a weighted kappa. Additionally, to determine the level of concordance between the visual determination of an open or closed apex and the apical foramen width measured in millimeters, a dichotomized kappa coefficient was applied. ResultsA good level of global observer agreement was found for the dichotomous, Demirjian, and Cvek classifications. However, a significantly low percentage of total concordance and global observer agreement (6.66% and 0.498, respectively) was obtained using the Moorrees classification, which was more pronounced among nonexperienced observers (0.247). Apical foramen width measurements indicated the presence of 143 roots with an open apex (50.2%) and 142 with a closed apex (49.8%), and the dichotomized kappa coefficient test revealed a good level of agreement during the visual determination of an open or closed apex (range, 0.611–0.636). ConclusionsThe classifications of Cvek and Demirjian provided reliable results when determining the different stages of root development. In contrast, the Moorrees classification provided the lowest agreement values, with a significant negative effect among nonexperienced observers. Finally, the visual estimation of the presence (or absence) of an open apex provided a good level of concordance with the radiographic apical foramen width.

Association of metabolic syndrome and cognitive function in a population‐based cross‐sectional study of adults aged 60 years or older

AbstractBackgroundMetabolic syndrome (MetS) is defined by the presence of five cardiovascular risk factors: diabetes, hypertension, high body weight, and hypercholesterolemia. Each factor has been reported to associate with cognition, but the association of MetS with cognitive function is not well understood. The current study explored the association of MetS with cognition in a nationally representative sample of elderly adults in the United States.MethodCross‐sectional data from the National Health and Nutrition Examination Survey (NHANES 2011‐2014) were obtained for participants age ≥60 years. MetS was defined per American Heart Association criteria (≥ 3/5 factors). Cognitive performance was based on components of the Consortium to Establish a Registry in Alzheimer’s disease (CERAD) neurocognitive battery. A composite z‐score was calculated for each CERAD component; z‐scores were then averaged to estimate global cognition (Figure 1). Memory complaint was based on self‐report. Linear regression models were fit to evaluate the association between global cognition and MetS, and logistic regression was used to evaluate the association of memory complaint with MetS; we used survey statistics to account for the complex NHANES sampling design.ResultIncluded participants (n=2593) were mean 69.4 years old; 54.8% (n=1318) were female. MetS was present in 60.9% (n=1633) of participants. After adjustment for age, sex, race/ethnicity, education, alcohol use, poverty, marital status, and memory complain, MetS was associated with almost 1/3 standard deviation lower mean global cognition compared to participants with no MetS factors (β= ‐0.28; 95%CI ‐0.46,‐0.10), while participants with 1‐2 MetS conditions had similarly lower cognitive scores relative to participants with none (β= ‐0.23; 95%CI ‐0.42,‐0.04) (Table 1). After adjustment for age, sex, race/ethnicity, education, alcohol use, poverty, marital status, and z‐score, MetS was not significantly associated with memory complaint (OR=0.90; 95%CI 0.33, 2.45).ConclusionOur findings suggest that MetS was associated with lower cognitive performance in older adults, but this association may be modified by participant characteristics. Participants who did not meet criteria for MetS but had 1‐2 risk factors showed similar cognitive performance to those with MetS, so focusing on dichotomous MetS classifications may obscure cognitive risks for those individuals who don’t fully meet the MetS criteria.

Does adequate physical activity attenuate the associations of alcohol and alcohol-related cancer mortality? A pooled study of 54 686 British adults.

The potential of physical activity (PA) to attenuate the effects of alcohol consumption on the risks of alcohol-related cancer mortality is unknown. We used data from participants aged 30 years and over in 10 British population-based surveys (Health Surveys for England 1994, 1997, 1998, 1999, 2003, 2004, 2006 and 2008 and the Scottish Health Surveys 1998 and 2003). Alcohol-related cancer mortality included oral cavity, throat, larynx, oesophagus, liver, colorectal, stomach and female breast (conservative definition), and additionally pancreas and lung (broad definition). Alcohol consumption was categorised into six groups based on the UK units/week: (a) never-drinkers, (b) ex-drinkers, (c) occasional drinkers, (d) within guidelines (<14 UK units/week [women]; <21 UK units/week [men]), (e) hazardous (14-35 [women]; 21-49 [men]) and (f) harmful (>35 [women]; >49 [men]). PA was categorised using two dichotomous classifications based on the lower (7.5 Metabolic Equivalent Task [MET]-hours/week) and upper (15 MET-hours/week) recommended limits. Using Cox proportional hazard models, we found a strong direct association between alcohol consumption and mortality risk of alcohol-related cancers, with a significantly higher risk among ex-drinkers (Hazard ratio [HR] = 1.46, 95% confidence interval [CI] = [1.09, 1.94]), drinkers who consumed hazardous (HR = 1.39, 95% CI = [1.06, 1.83]) and harmful amounts of alcohol (HR = 1.62, 95% CI = [1.13, 2.30]) compared to never-drinkers in the fully adjusted model. The increased mortality risks were substantially attenuated when participants in these drinking groups exercised >7.5 MET-hours/week. PA could be promoted as an adjunct risk minimisation measure for alcohol-related cancer prevention.

Ability of the United States Air Force Family Needs Screener to Predict Child Maltreatment: A Prospective Study

In the current study, we examined the extent to which the United States Air Force Family Needs Screener (FNS)—a scale that purportedly measures risk for child maltreatment–predicted future child maltreatment in a group of 87,982 mothers. Mothers’ FNS total scores predicted future child maltreatment overall (i.e., any type of maltreatment) and for individual types of child maltreatment (i.e., child physical abuse, child emotional abuse, and child neglect). Further, results did not vary across Air Force installations. Beyond the standard dichotomous FNS classifications (Low-Needs and Low-Needs), the finding that as individual FNS total scores increased so did the likelihood of future child maltreatment suggests that mothers with the highest FNS scores—even among those deemed high needs—may warrant special attention.

P249 Working with axSpA: a qualitative study using the British Society for Rheumatology Biologics Register

Abstract Background We have previously reported that axSpA patients living in rural areas report a greater impact of their disease on work productivity. Whilst rural dwellers were more likely to work in a physical job and work part-time, it is unclear how features of the disease, job type and work environment interact to influence presenteeism (work disability). We aimed to explore experiences of work and factors influencing the ability to work optimally in individuals with axSpA. Methods 30 semi-structured telephone interviews were conducted from a subset of patients drawn from the British Society for Rheumatology Biologics Register for Ankylosing Spondylitis (BSRBR-AS) registry. Individuals were purposively sampled across a range of ages, area of residence (urban and rural), occupations (sedentary and manual), employment status and stage of working life, from diverse geographical regions in the UK. The topic guide explored experiences of living with AxSpA, work, health care and impact of AxSpA on family, financial and social life over time. Interviews were audio-recorded and transcribed. Data was analysed using an iterative thematic approach, supported by NVivo 12 qualitative data analysis software. Results Factors influencing presenteeism are considered under three themes; occupation, individual and workplace. Occupation: The extent to which jobs permitted flexibility, in terms of what, when and how tasks were done, was important. Dichotomous classifications of job type as sedentary or manual were unhelpful. Participants, especially in public facing jobs, reported an obligation to attend work even when feeling unwell. Individual: Work was important in terms of self-identity and providing social interactions as well as financial security. However, fatigue, reduced mobility, chronic pain and medication affected physical and mental function at work. Individuals did not discuss work issues with their rheumatologist, who tended to focus on disease management. Workplace: Support from work colleagues and immediate line managers was critically important, over and above organisational policies. However, AxSpA was often misunderstood, for example, as ‘a bad back.’ Flexible working practices e.g. home-working enabled individuals to continue to work, when they would otherwise have been unable to. Adaptations to driving and commuting to work were common. Some employers permitted adjustments to working practices or time off for appointments, whereas others were inflexible. Sickness monitoring procedures were often perceived to be punitive, rather than supportive. Conclusion The relationship between job type, work environment and work disability is nuanced and complex. Existing measures of work do not accurately reflect what people actually do, the challenges they face, or the benefits of work. Flexibility in terms of what, when and how tasks are done is important. There is significant variation in support offered by employers. Healthcare professionals can do more to support individuals to work well and educate employers. Disclosures R.J. Hollick None.

Beyond a sedentary Other and a mobile tourist: Transgressing mobility categories in the informal tourism sector in India

Taking the informal tourism sector in India as a case study, this article demonstrates ethnographically that dichotomous classifications often taken for granted when conceptualizing human mobilities are undermined in people’s everyday practices. One of them is the binary between mobile cosmopolitan tourists (“guests” from the Global North) and local “hosts” (i.e. service providers from the Global South), who are denied the right to be mobile. The aim of the article is to overcome these outdated anthropological conceptualizations of the sedentary Other, based on ethnological naturalism and currently reproduced in the tourism marketing, in the context of global mobility regimes. The article shows that a high level of mobility is not only an attribute of tourists, but it also characterizes the “locals,” who work in the informal tourism sector in India. It also reveals the multiple ways that various forms of people’s spatial mobility – such as tourism and migration – intersect.

Relationship between Cyclic and Non-Cyclic Force-Velocity Characteristics in BMX Cyclists.

Especially for bicycle motocross (BMX) cyclists, transfer of muscular force-velocity (Fv) characteristics between common strength training exercises and cycling is important. This study investigated the relationship between Fv characteristics in a common training exercise (squat jumps) and a sport-specific task (cycling) in high-level BMX racers by exploring the degree to which Fv and torque–cadence (Tc) characteristics correspond. Twelve BMX racers performed an Fv (multiple loaded squat jump) and two Tc tests (ramp starts and flat-ground sprints). Results revealed very large correlations between and (r = 0.77) and between and (r = 0.85). On the other hand, the relationships between and (r = –0.25) and between and (r = –0.14) were small and negative. Similar results were observed for sprints. Based on dichotomous classifications (greater or less than group median), several discrepancies occurred, particularly for the profile slopes and high-speed variables. Thus, we recommend performing both jump-based and cycling-specific testing. Of additional note, characteristics on flat ground were similar to, but slightly different from those on the start ramp. Therefore, where possible, Tc tests should be carried out on a ramp.

RegulationSpotter: annotation and interpretation of extratranscriptic DNA variants.

RegulationSpotter is a web-based tool for the user-friendly annotation and interpretation of DNA variants located outside of protein-coding transcripts (extratranscriptic variants). It is designed for clinicians and researchers who wish to assess the potential impact of the considerable number of non-coding variants found in Whole Genome Sequencing runs. It annotates individual variants with underlying regulatory features in an intuitive way by assessing over 100 genome-wide annotations. Additionally, it calculates a score, which reflects the regulatory potential of the variant region. Its dichotomous classifications, ‘functional’ or ‘non-functional’, and a human-readable presentation of the underlying evidence allow a biologically meaningful interpretation of the score. The output shows key aspects of every variant and allows rapid access to more detailed information about its possible role in gene regulation. RegulationSpotter can either analyse single variants or complete VCF files. Variants located within protein-coding transcripts are automatically assessed by MutationTaster as well as by RegulationSpotter to account for possible intragenic regulatory effects. RegulationSpotter offers the possibility of using phenotypic data to focus on known disease genes or genomic elements interacting with them. RegulationSpotter is freely available at https://www.regulationspotter.org.

Evidencias de validez de constructo y de criterio de la Escala Massie-Campbell de Apego Durante Estrés (ADS)

The Massie-Campbell Attachment During Stress Scale (ADS, Massie & Campbell, 1983) is an observation guide of the interactions between mothers (or caretakers) and children from 6 to 18 months. This study sought the construct validity (convergent and discriminant) of ADS, as well as its criterion validity (sensitivity, specificity, and predictive values). To that end, child attachment was measured in a group of 32 children aged 8 to 10 months from Lima, Peru using ADS and Attachment Q-set 3.0 (AQS, Waters, 1995). Maternal sensitivity was assessed as well. It was found that ADS attachment classifications were related to AQS attachment security continuous scores ( r = .41, p = .02) and to its dichotomous classifications [secure vs. insecure; χ2 (1, N = 32) = 4.69, p = 0.03, d = 0.83]. Additionally, no significant differences between the ADS’s maternal sensitivity of mothers with children classified as secure and mothers with children classified as insecure were found. Since ADS´s sensitivity did not reach satisfactory levels (33.3 %, 95 % CI = [15.48, 56.90]), a cut-off point of 5 secure behaviors was used, which improved its sensitivity (47.6 %, 95 % CI = [26.4; 69.7]) while maintaining satisfactory levels of specificity (90.9 %, 95 % CI = [57.1; 99.5]). The instrument shows adequate convergent validity but lacks evidence of discriminant validity. Further exploration of ADS’s sensitivity, specificity, and predictive values is recommended in order to obtain a cut-off point with greater validity, given that the instrument is considered a screening test.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P137. The effects of operating room size on surgical site infection following lumbar fusion surgery

BACKGROUND CONTEXT Surgical site infection is a rare yet potentially serious complication impacting 0.3%–9% of patients undergoing surgery. While it is clear that patient and procedure-related risk factors affect the risk of infection, it is likely that environmental factors also affect rates of infection. PURPOSE To investigate the effect of operating room size on surgical site infection following lumbar fusion surgery. STUDY DESIGN/SETTING Retrospective case-control study. PATIENT SAMPLE Adult patients with a one- to three-level lumbar fusion at a single institution between January 1, 2012 and December 31, 2016. OUTCOME MEASURES Surgical site infection. METHODS Data were collected for all one- to three-level lumbar fusion surgery cases performed at a single institution by fellowship-trained spine surgeons between 2012 and 2016. Infection data was provided by the Infection Control Committee of the institution, and patients were considered to have an SSI if they met the Centers for Disease Control and Prevention's National Healthcare Safety Network definition of a surgical site infection. Data was analyzed to assess the relationship of operating room size and surgical site infection along with the effect of other medical comorbidities and covariates on infection. OR size was recorded as both floor surface area and room volume, and subsequently analyzed using dichotomous (small vs. large) classifications with a transition point as the mean measurement for each category. The mean surface area was 533.39 ft2 and volume was 5071.28ft2. These were selected as the cutoff point between small and large operating rooms as they represent the 50th percentile measurement. Of the 17 ORs analyzed, nine fit the criteria for “large” and eight fit the criteria for “small.” RESULTS A total of 1,864 patients were included and 33 were determined to have an SSI (1.77%). Demographics were not significantly different between the patient groups. OR size was not significantly associated with surgical site infection (multivariate p=.319). Laminar flow, vancomycin powder use, levels decompressed and the presence of several other covariates were also not significantly associated with surgical site infection (multivariate p>0.05). Factors that were found to increase the odds of infection included age>65, BMI>30 and smoking status (multivariate p CONCLUSIONS Operating room size is not significantly related to an increased incidence of surgical site infection following 1, 2 or 3 level lumbar fusion surgery. Conversely, this study reaffirmed that at age, BMI and smoking are risk factors for infection.

NIH Toolbox Picture Sequence Memory Test for Assessing Clinical Memory Function: Diagnostic Relationship to the Rey Auditory Verbal Learning Test.

The NIH Cognitive Toolbox Picture Sequence Memory Test (PSMT) was developed as a measure of learning ability. PSMT use in clinical populations is only beginning to be investigated. PSMT performance was analyzed in a retrospective series of 221 patients referred to either the Deep Brain Stimulation Clinic (n = 128) for presurgical evaluation, or to the Cognitive Screening Clinic (n = 93). Patients were also administered the Rey Verbal Auditory Verbal Learning test (AVLT). In addition to correlation between measures, classification agreement was examined based upon performance ratings of normal (>16th percentile), borderline (5-16th percentile), or impaired (<5th percentile). Correlation between measures was significant (r = 0.48, p < .0001), with classification agreement of 62% (weighted Kappa = 0.43). For patients with valid PVT scores (n = 147), correlation between tests was 0.67 (p < .0001) with a classification agreement of 72% (weighted Kappa = 0.44). Multiple level likelihood ratios (LRs) relating PSMT to various dichotomous AVLT learning classifications were modest, with the largest group LR obtained for impaired PSMT increasing the likelihood of obtaining impaired AVLT by 7.62 (95% CI = 3.54-16.42). Despite significant correlations between measures, the NIH Toolbox PSMT and AVLT learning score often generate different interpretive results. Impaired PSMT appears better at predicting impaired AVLT performance rather than predicting combined borderline/impaired AVLT performance. Ultimately, individual clinicians will need to determine whether the PSMT can be used independently without other memory tests in the clinical environment in which they practice while further validation studies are performed.

FDG-PET and CSF biomarker accuracy in prediction of conversion to different dementias in a large multicentre MCI cohort.

Background/aimsIn this multicentre study in clinical settings, we assessed the accuracy of optimized procedures for FDG-PET brain metabolism and CSF classifications in predicting or excluding the conversion to Alzheimer's disease (AD) dementia and non-AD dementias.MethodsWe included 80 MCI subjects with neurological and neuropsychological assessments, FDG-PET scan and CSF measures at entry, all with clinical follow-up. FDG-PET data were analysed with a validated voxel-based SPM method. Resulting single-subject SPM maps were classified by five imaging experts according to the disease-specific patterns, as “typical-AD”, “atypical-AD” (i.e. posterior cortical atrophy, asymmetric logopenic AD variant, frontal-AD variant), “non-AD” (i.e. behavioural variant FTD, corticobasal degeneration, semantic variant FTD; dementia with Lewy bodies) or “negative” patterns. To perform the statistical analyses, the individual patterns were grouped either as “AD dementia vs. non-AD dementia (all diseases)” or as “FTD vs. non-FTD (all diseases)”. Aβ42, total and phosphorylated Tau CSF-levels were classified dichotomously, and using the Erlangen Score algorithm. Multivariate logistic models tested the prognostic accuracy of FDG-PET-SPM and CSF dichotomous classifications. Accuracy of Erlangen score and Erlangen Score aided by FDG-PET SPM classification was evaluated.ResultsThe multivariate logistic model identified FDG-PET “AD” SPM classification (Expβ = 19.35, 95% C.I. 4.8–77.8, p < 0.001) and CSF Aβ42 (Expβ = 6.5, 95% C.I. 1.64–25.43, p < 0.05) as the best predictors of conversion from MCI to AD dementia. The “FTD” SPM pattern significantly predicted conversion to FTD dementias at follow-up (Expβ = 14, 95% C.I. 3.1–63, p < 0.001). Overall, FDG-PET-SPM classification was the most accurate biomarker, able to correctly differentiate either the MCI subjects who converted to AD or FTD dementias, and those who remained stable or reverted to normal cognition (Expβ = 17.9, 95% C.I. 4.55–70.46, p < 0.001).ConclusionsOur results support the relevant role of FDG-PET-SPM classification in predicting progression to different dementia conditions in prodromal MCI phase, and in the exclusion of progression, outperforming CSF biomarkers.