Difference Score Method Research Articles

Does Perceived Similarity Between Present and Future Self Predict Well-Being? A Reanalysis and Replication of Reiff et al. (2020)

Reiff and colleagues found that perceived similarity between one’s present and future self is positively associated with life satisfaction 10 years later, using a difference-score approach to operationalize similarity. This study further evaluated the similarity effect by reproducing the original longitudinal association with a difference-score method, by using more sophisticated analyses (i.e., polynomial regression and response surface analyses), and by replicating the association in a newly collected sample. We were able to reproduce and replicate the findings based on a difference-score approach. However, we did not find a similarity effect in either sample using more sophisticated approaches. The current results show that previously reported support for the association between perceived similarity and well-being is driven by the statistical main effects of personality reports.

Quotient Types from Mahabharata & Ramayana

Purpose: Our world is shifting at an exponential rate. Difficulties are more complicated. Uncertainty is the norm. Improving our Qs is seen as one of the most commanding quotients for success. The quotients in today’s concern are ones that will have a predominant influence on life and business. Quotients are the degree or expanse of a specified quality/characteristic. We know there are several quotients used to portray specific characteristics of an individual. For example, most individuals have heard of IQ, also known as the Intelligence Quotient, which consists of a score designed to gauge the overall intelligence of a human being. However, not everyone knows other quotient types exist and represent much more about an individual, including their spiritualness, level of creativity, and ability to communicate and learn in specific ways. The researcher’s paper also throws light on how it works and how to recharge Qs tests & training at a workplace if one tries it as his/her daily menu. Which of these Qs is most essential for a leader? or which combination? Does a leader need to score strongly in all areas, or to employ those with the necessary scores to complement their own deficiencies? Are the questions to be answered? Thus, linking mythological themes & management with the present-day materialistic world is not easy. The present research links and contextualizes the concepts of Qs through Mahabharata & Ramayana with the ancient Mythology. Objectives: The researchers have set the undermentioned primary objectives and the existing study investigates 3 broad research questions: (1) To evaluate quotients types that have an impact on individual from Mahabharata & Ramayana characters. (2) To examine the need for Qs for workplace tests & training. (3) To identify the Q's impact on individual behaviour. Design/Methodology/Approach: The study is based on both secondary & primary evidence. Hypotheses are stated for the various variables selected and analyzed to prove or disprove the same without any errors. Findings/Result: Qs tests & training are a leading light in the corporate learning and team building industries with large and small organizations to assist team members in better understanding one another while effectively collaborating and boosting individual and team morale and productivity in the workplace with Qs test. Trying workplace Qs tests & training is a new catchword. Researchers have found when co-workers participate in Qs-related training programs, it may help improve their: teamwork, conflict management abilities, job performance & general job satisfaction. Qs also gives you a chance to submerge yourself in the know-how of other people whether those people really exist or are fictional characters. Studies show that Qs may help improve your social thinking skills, which researchers think is noteworthy for building empathy. Researchers have found that when people practice Qs between ideas and objects, scores on measures of general intelligence tend to improve. Research Limitations/Implications: There’s no proof that cognitive training raises overall Qs. Though, you can and should continue to learn throughout your life. The keys to learning tend to encompass curiosity and being receptive to new information. With those qualities Qs, you can enhance your ability to: Concentrate, remember details, empathize, grasp new concepts, enrich your imagination, research & add to your knowledge base. Originality/New Knowledge/Interpretation/Value: Qs tests have gone through substantial changes through the decades to correct racial, gender, and social biases, as well as cultural norms. Today, there are several versions in use. They may have different methods of scoring, but they all are used in one way or the other. Qs tests can gauge language, processing, memory, and reasoning and can tend to check whether Qs remain consistent from childhood to adulthood in an individual. Paper Type: The study is based on both secondary & primary evidence.

Contrasting speed and accuracy approaches to measure executive functions in three low-and middle-income countries.

Executive functions (EF) can be measured by tests assessing accuracy, reaction times and by computing scores which combine these two components. Interpretation issues can arise from the use of different scoring methods across studies. Given that EF measures and their scoring methods are predominantly developed and validated in high income countries, little is known about the generalisability of such methods cross- culturally. The current paper compares two different established scoring approaches for measures of inhibition and cognitive flexibility: difference scores (which utilise reaction time only) and computed scores (combining accuracy and reaction time). We utilised data collected in adulthood from three low- and middle-income birth cohorts (Guatemala, Philippines, South Africa). Non-normal distributions were observed for both scoring methods in all three samples; however, this was more pronounced for the difference score method. Differing distribution patterns were observed across the three cohorts, which was especially evident in the Guatemala cohort, highlighting potential issues with using these methods across diverse populations. The data suggest that the computed scores may be a reliable measure of EF. However, the different ways of scoring and interpreting EF instruments need to be considered carefully for each population before use.

P479 Reliability and responsiveness of histologic disease activity indices in Crohn’s Disease

Abstract Background The operating properties of histologic indices are poorly characterized in Crohn’s disease (CD) and no validated index exists. We assessed the reliability and responsiveness of histologic indices/items, developed an exploratory index, and compared different methods of scoring. Methods Using baseline and week 12 histologic image sets from the EXTEND placebo-controlled trial, blinded central readers scored 4 histologic indices (the Global Histologic Activity Score [GHAS], Geboes Score [GS], Robarts Histopathology Index [RHI], and Nancy Index [NHI]) and 3 additional novel items identified by an expert panel (mucin depletion, basal plasmacytosis, and pyloric gland metaplasia in the ileum). Reliability and responsiveness were evaluated for a global score (4 colonic segments + ileum), colonic score (4 colonic segments) and ileal score (ileum only) using the intraclass correlation coefficient (ICC) and area under the receiver operating curve (AUC), respectively. Change was defined using treatment assignment and improvement in histologic disease activity as measured on a 100-mm visual analogue scale (VAS) in responsiveness testing. Exploratory indices were developed using backward stepwise linear regression analysis. Candidate independent variables were items with an ICC ≥0.4 and AUC ≥0.56. The VAS served as the dependent variable. Results Paired histologic images were analysed from 55 subjects. Inter-rater reliability was substantial to almost perfect (ICC=0.73-0.85) and responsiveness was small to large (treatment assignment AUC=0.50-0.65; VAS AUC=0.71-0.94). The GHAS, GS, RHI, and NHI reached the minimum threshold for reliability (ICC ≥0.4) and responsiveness (AUC ≥0.56) regardless of whether the global and colonic scores were calculated using the worst affected segment, average of the included segments, or sum of the included segments (Table 1-3). Five items were tested as candidate predictors. Three exploratory indices were developed, each consisting of 3 items: a global index (neutrophils in the lamina propria, neutrophils in the epithelium, and erosion/ulceration), colonic index (chronic inflammatory infiltrate, neutrophils in the lamina propria, and erosion/ulceration) and ileal index (chronic inflammatory infiltrate, neutrophils in the epithelium, and erosion/ulceration). The novel indices highly correlated with the GHAS, GS, RHI, and NHI, with correlation coefficients ≥0.80 (Table 4). Conclusion The 4 existing indices were similarly reliable and responsive in measuring CD histologic activity, regardless of the method for calculating global and colonic scores and could be used in clinical trials. Attempts at novel index development did not offer benefit over current histologic indices.

Couples’ self-control and marital conflict: Does similarity, complementarity, or totality matter more?

Research that approached self-control as a dyad-level predictor of relationship outcomes is hitherto scarce. To address this research gap, this study investigates three configurations of couples’ level of self-control on marital conflict. We test three competing hypotheses suggested in the literature: similarity hypothesis, complementarity hypothesis, and totality hypothesis. The data used to test these hypotheses is a unique couple data (N = 1698 individuals from 894 married couples) of husbands and wives from a representative sample in Hong Kong. Two-level random-intercept models were employed. Based on our analysis with the difference-score method and response surface analysis, we find evidence to support the similarity hypothesis. The similarity of self-control between husband and wife is important in predicting marital conflict. In contrast, the total level of self-control is not predictive of marital conflict. This study highlights that marital conflict is strongly associated with the mismatch of self-control between partners.

A comparison of metric scoring and health status classification methods to evaluate benthic macroinvertebrate-based index of biotic integrity performance in Poyang Lake wetland

Methods for metric scoring and health status classification in development of index of biotic integrity (IBI) vary considerably across published studies. The difference between ecosystem health assessment results from these alternative methods for scoring and classification has rarely been studied systematically. Poyang Lake in China has experienced severe degradation over recent decades. Here, we aimed to develop a benthic macroinvertebrate-based index of biotic integrity (B-IBI) to assess the wetland health of Poyang Lake, and to evaluate the difference in assessment results using different methods of scoring and classification. Data on benthic macroinvertebrate assemblages, water quality and human-induced disturbances were collected at 30 sampling sites. Forty-nine attributes of macroinvertebrate assemblages were tested, and only the attributes that were significantly correlated with disturbance gradients or showed strong discriminatory power between reference and impaired sites were selected as the B-IBI metrics. Two scoring, two thresholding and three classification methods were applied for metric scoring and health status classification. Five assemblage attributes, i.e. the number of taxa, Shannon-Wiener diversity index, % Diptera, ASPT index and the number of predator taxa, were selected as the B-IBI metrics. Health status assessments varied considerably among the various metric scoring and classification methods, suggesting the importance of standardizing the methods for scoring and classification to be able to compare assessment results across different areas and time periods. The wetland health of Poyang Lake was rated as fair, which indicates that the wetland has experienced anthropogenic pressure and substantial changes in macroinvertebrate assemblage structure. Further, sample sites adjacent to tributary river mouths were in poor or very poor condition, suggesting that pollutant input by rivers has strong negative impacts on wetland health. Effective management of the entire lake basin and its watershed is therefore important for the wetland conservation.

Construct Validity of Two Different Methods of Scoring and Performing Push-ups.

Clemons, J. Construct validity of two different methods of scoring and performing push-ups. J Strength Cond Res 33(11): 2971-2980, 2019-The purpose of this investigation was to determine the construct validity of the standard push-ups (STPUs) and hand-release push-ups (HRPUs) by comparing them to the criterion measures of absolute strength (i.e., 1 repetition maximum [RM] bench press [BP]) and relative strength (1RM·body mass). Thirty-one, college-age males were recruited for the study. The HRPU was performed by lifting the palms from the floor between each push-up (PU), whereas the STPU only required chest contact at the bottom before returning to the support position. Push-up rate was controlled by metronome. A counter-balanced, cross-over design was used with 1 week between each test. Correlations were conducted on push-up scores and criterion measures. In addition, STPU and HRPU scores were compared to determine whether there was a difference in the maximum number of push-ups executed. Multiple regression analysis was used to determine whether 1RM BP (i.e., absolute strength) might be predicted from push-up performance: 1RM Bench Press kg = 48.675 + (0.8832·body mass) + (1.318·# of standard push-ups executed) + (-157.82·PU distance m). Results indicated significantly more HRPUs than STPUs were executed. Push-up raw scores were found to be unrelated to absolute strength. Standard push-up raw scores were found to be significantly correlated with relative strength (r = 0.71, prob. = 0.0001). Multiple regression analysis also indicated that absolute strength may be reasonably estimated if the predictor variables of body mass and vertical push-up distance are considered along with push-up score (R = 0.791, R = 0.62.5%).

An incremental training method with automated, extendable maze for training spatial behavioral tasks in rodents

We present a training procedure and maze equipped with sensors and automated feeders for training spatial behavioral tasks in rodents. The maze can be transformed from an enclosed box to a maze of variable dimensions. The modularity of the protocol and setup makes it highly flexible and suitable for training a wide variety of spatial tasks, and facilitates incremental training stages of increasing maze size for more efficient learning. The apparatus, in its software and hardware, is able to adapt to animal performance, adjusting task challenges and difficulty. Two different methods of automatic behavioral scoring are evaluated against manual methods. Sensors embedded in the maze provide information regarding the order of reward locations visited and the time between the activation of the cue via the nose-poke and the activation of the reward location sensors. The distributions of these reaction times differ between correct and incorrect trials, providing an index of behavior and motivation. The automated maze system allows the trainer to operate and monitor the task away from the experimental set-up, minimizing human interference and improving the reproducibility of the experiment. We show that our method succeeds in training a binary forced-choice task in rats.

A deep neural network for real-time detection of falling humans in naturally occurring scenes

We introduce a novel approach to the problem of human fall detection in naturally occurring scenes. This is important because falling incidents cause thousands of deaths every year and vision-based approaches offer a promising and effective way to detect falls. To address this challenging issue, we regard it as an example of action detection and propose to also locate its temporal extent. We achieve this by exploiting the effectiveness of deep networks. In the training stage, the trimmed video clips of four phases (standing, falling, fallen and not moving) in a fall are converted to four categories of so-called dynamic image to train a deep ConvNet that scores and predicts the label of each dynamic image. In the testing stage, a set of sub-videos is generated using a sliding window on an untrimmed video that converts it to multiple dynamic images. Based on the predicted label of each dynamic image by the trained deep ConvNet, the videos are classified as falling or not by a “standing watch” for a situation consisting of the four sequential phases. In order to localize the temporal extent of the event, we propose a difference score method (DSM) based on adjacent dynamic images in the temporal sequence. We collect a new dataset, called the YouTube Fall Dataset (YTFD), which contains 430 falling incidents and 176 normal activities and use it to learn the deep network to detect falling humans. We perform experiments on datasets of varying complexity: Le2i fall detection dataset, multiple cameras fall dataset, high quality fall simulation dataset and our own YouTube Fall Dataset. The results demonstrate the effectiveness and efficiency of our approach.

The ISIS-TTRRx-CS2 phase 3 study in patients with familial amyloid polyneuropathy: Baseline results of the first 100 patients for the NIS, NIS+7 and mNIS+7 using different methods of scoring: identification of consistencies and key differences

Background Familial amyloid polyneuropathy (FAP) is a devastating disease with continuous progression over time leading to complete disability, bedridden status, and ultimately death within 10 to 15 years from symptom onset. In order to document disease progression, it is necessary to have valid instruments which allow assessment of the severity of the sensory, motor and autonomic neuropathy components of the disease. Over the last decades, multiple related instruments have been used and modifications developed to measure disease progression in FAP patients in clinical trial settings. These include the Neuropathy Impairment Score (NIS), originally called Neuropathy Disability Score, the Neuropathy Impairment Score for the Lower Limbs (NIS-LL), the Neuropathy Impairment Score +7 (NIS+7) and the modified NIS +7 (mNIS+7). The NIS scores were first used to quantitate neuropathic impairment in a series of therapeutic trials in chronic inflammatory demyelinating polyradiculoneuropathy and were also used as primary endpoints in clinical trials for FAP in the completed diflunisal (NIS+7) and tafamidis (NIS-LL) Phase 3 trials. Building on experience from these trials, modifications to the NIS+7 were developed (Suanprasert et al, 2014, J Neurol Sci) and are currently being applied in the ongoing ISIS-TTRRx-CS2 (mNIS+7 Isis) and patisiran (mNIS+7 ALN) Phase 3 trials. Even though the mNIS+7 Isis and mNIS+7 ALN scores are very similar, they are not identical. The details in the assessment and scoring for the various versions of the NIS based scores are described and their scoring methods applied to baseline data collected on the first 100 patients in the ISIS-TTRRx-CS2 trial to better understand and illustrate the key differences.

Wirksamkeit von Umweltzonen in der ersten Stufe: Analyse der Feinstaubkonzentrationsänderungen (PM10) in 19 deutschen Städten

It is not known/is disputed whether introduction of low emission zones (LEZs) leads to a reduction of fine dust pollutants. Data on PM10 concentrations obtained from measurement stations within and outside of LEZs from 19 German cities (Augsburg, Berlin, Dortmund, Duisburg, Düsseldorf, Essen, Frankfurt a. M., Hannover, Herrenberg, Ilsfeld, Karlsruhe, Köln, Ludwigsburg, Mannheim, München, Reutlingen, Stuttgart, Tübingen, Wuppertal) were analyzed in order to investigate the effect of banning vehicles ("tier 1") of the pollutant group 1 (without stickers) on the pollutant concentration, i.e, this study focused on LEZs that restricted cars of EURO 1 standard without appropriate retrofitting systems from entering these zones. For the period from about 2005 until the end of 2009, data from continuous half-hour measurements as well as gravimetrically determined daily measurements of PM10 were collected. The analysis consisted of four pairwise corresponding measurement values as matched quadruples of two index and two reference values (index stations are inside, and reference stations are outside the LEZs). One index value and the simultaneous reference value were measured during the active LEZ period, and the other pair of values was measured before the LEZ was introduced. The pairs of values had a difference in time of 364 days or a multiple of 364 days keeping the season, weekday and time of day constant within the quadruple. Differences in index values were regressed on differences in reference values while meteorological parameters (height of the inversion base, amount of precipitation, wind velocity), school holidays, period of environmental bonus paid, periods when trucks were banned as well as baseline data at index and reference stations were taken into account as covariates in so-called "fixed effects" regression analyses of the quadruples (difference score method in the two-period case). The statistical approach was successfully validated prior to this study in an analysis of simulated data from FU Berlin. 2,110,803 quadruples of continuous PM10 and 15,735 gravimetric quadruples were identified leading to 61,169 quadruples based on daily PM10 averages. The analyses showed that best LEZ effect estimates for fine dust reduction were (at all index stations) ≤ 0.2 μg/m3, i. e., a relative PM10 reduction ≤ 1 %. Best estimates at all index stations near traffic (excluding urban background and industry index stations) were below 1 μg/m3 (less than 5 %, respectively). Effects were smaller than predicted prior to the introduction of LEZs. This study is the first that investigated comprehensively the effectiveness of "tier 1" LEZs in Germany on PM10 reduction with a homogeneous approach in data collection and analysis and taking into account the most relevant confounding factors.

A Monte Carlo Comparison Study of the Power of the Analysis of Covariance, Simple Difference, and Residual Change Scores in Testing Two-Wave Data.

This study compares the analysis of covariance (ANCOVA), difference score, and residual change score methods in testing the group effect for pretest–posttest data in terms of statistical power and Type I error rates using a Monte Carlo simulation. Previous research has mathematically shown the effect of stability of individual scores from pretest to posttest, reliability, and nonrandomization (i.e., pretest imbalance) on the performance of the ANCOVA, difference score, and residual change score methods. However, related power issues have not been adequately addressed. The authors examined the impact of stability of measurement over time, reliability of covariate and criterion, nonrandomization, sample size, and treatment effect size on statistical power of the three methods. Across conditions, ANCOVA and residual change score methods had similar power rates. When reliability was less than perfect, ANCOVA had more power than the difference score method when there was an increase from pretest to posttest and a positive baseline imbalance (i.e., treatment group had higher pretest scores than the control group), or when there was a decrease from pretest to posttest and a negative baseline imbalance, and vice versa. In case of perfect reliability, the statistical power of ANCOVA did not differ from the difference score method. For the difference score method, when reliability was low, there was no effect of stability on power, whereas when reliability was high or perfect, power increased as stability increased for medium and large effect sizes. Difference scores may be preferred over ANCOVA under certain circumstances.

Testing the Moderating Effect of Parent–Adolescent Communication on the Acculturation Gap–Distress Relation in Korean American Families

Although the acculturation gap generally has been associated with poor mental health outcomes among Asian American children, some studies have failed to find a significant relationship between the gap and distress. Using two different methods of operationalizing the gap between mothers and their children, the current study addressed this tension in the literature by testing the following hypotheses in a sample of Korean American families. It was hypothesized that mother-adolescent discrepancies in acculturation and enculturation levels would be associated with youth internalizing and externalizing symptoms and that parent-adolescent communication would moderate the gap-distress relationship. Multi-informant questionnaires were administered to 77 Korean American mother-adolescent dyads from the Midwest. Surprisingly, results indicated that consonance in low levels of mother-adolescent enculturation was associated with the highest levels of externalizing symptoms (interaction term method). Adolescents' perception of communication with their fathers significantly moderated the relationship between the enculturation gap and internalizing symptoms, such that in dyads with a greater enculturation gap, less perceived open communication with fathers was associated with more internalizing symptoms (difference score method). Clinically, the findings indicate a potential target (i.e., parent-adolescent communication) for treatment programs that aim to improve family relations and youth adjustment in immigrant families.

Comparative Effects of Circuit Training Programme on Speed and Power of Pre- and Post- Menarcheal Girls

This study examined the Comparative Effects of Circuit Training Programme on Speed and Power of Pre- and Post-Menarcheal girls. A pre-test- posttest control group experimental design was used to carry out the study. A total of 80 Secondary School girls from St. Peter's College, Olomore, Abeokuta, in Ogun State of Nigeria, ages 10-17 years took part in the study. The subjects were not involved in competitive school sports. Stratified random sampling technique was used to select 40 pre-menarceal and 40 postmenarcheal girls who were later randomly assigned to experimental and control groups. At the end of the training programme, 40 subjects completed the post training measurements, so there were 10 subjects in each of the four study groups (pre-menarcheal experimental, pre-menarcheal control, post-menarcheal control, post-menarcheal experimental, postmenarcheal control groups). The data collected were subjected to descriptive statistics of mean and standard deviation and inferential statistics of Analysis of Covariance (ANCOVA) (2-ways) using the difference score method to test the hypotheses for the study at 0.05 level of significance. Where there was any significant F, Scheffé post-hoc analysis was used for further analysis. The result showed that in general, maturation and training accounted for a lot of the differences in the performance of the study groups. There was no significant difference in power of pre- and post- menacheal girls as a result of 12-weeks circuit training programme. The findings also indicated that the main effects of factor A (Status: pre- and post- menarcheal girls) and factor B (Study Conditions: Experimental and Control) were statistically significant. The effects of the training on speed was significantly better for pre-menarcheal girls than for post-menarcheal girls (Post test 9.32; 9.56). Subjects in the experimental groups had better power than those in the control groups. The Implications of this study are that exercise training such as the circuit used in this study can make observable differences in speed and power of adolescents. Effective exercise training programmes should therefore be considered as an integral and inevitable aspect of school curriculum. African Journal of Educational Studies in Mathematics and Sciences Vol. 5 2007: pp. 35-42

Stroop interference and attention-deficit/hyperactivity disorder: A review and meta-analysis.

Previous reviews and meta-analyses that addressed abnormal Stroop interference in attention-deficit/hyperactivity disorder (ADHD) yielded mixed results. The authors of the present study argue that the inconsistencies may reflect the problematic nature of 2 frequently used methods to quantify Stroop interference-the difference score and Golden's method (C. J. Golden, 1978). Golden's method correction for base-word reading is inadequate, and the difference score is sensitive to the nature of the outcome variable. The latter can be remedied with a ratio score. Contrasting previous meta-analyses, this meta-analysis covers all age groups and all Stroop test variants, and it excludes studies using the Golden quantification method. Mean effect sizes for interference in ADHD as quantified by difference scores relative to control scores were 0.24 across all studies but 1.11 for time-per-item studies; outcome variable was a significant moderator variable, reflecting the sensitivity of the difference score to this variable. Consistency analysis of ratio scores across 19 studies reveals more interference for the ADHD groups relative to the control groups. It is concluded that interference control is consistently compromised in individuals with ADHD.

Measurement of lateral preferences and schizophrenia: results of the Edinburgh High-Risk Study and methodological issues

The assessment and measurement of handedness has varied across studies, limiting the comparability of results. Data from the Edinburgh High Risk for Schizophrenia Study were analyzed to investigate the effect of different methods of assessment and scoring of hand preferences on the prevalence of handedness type and on between-group differences in handedness. Handedness was measured using both the Edinburgh Handedness Inventory and the Annett Handedness Scale in 143 subjects at high risk for schizophrenia, 31 control subjects, and 27 patients with a first episode of schizophrenia. Hand preferences were identified through demonstration of items and by verbal report. No group differences were found, although the prevalence of hand preferences changed substantially depending on the definition used. Significant correlations with socio-demographic factors were found in some instances, but these correlations depended on the definition of handedness. No sex differences were identified. The magnitude of group differences remained similar, although the prevalence of handedness types varied greatly with changes in definition of handedness. Care should be taken in correlation studies to avoid spurious relationships between handedness and other factors. To allow for comparability of results across studies, researchers should adopt a standard definition of handedness.

Identification of Underachievers in Hong Kong: Do different methods select different underachievers?

Although academic underachievement is a familiar topic in educational research, there is no consensus on how underachievers should be selected. This study aimed to compare different selection methods, absolute split method, simple difference score method, regression method and nomination, in the identification of underachievers from a sample of 126 Chinese Grade 7 students. The results indicated that the three different statistical methods showed high congruence in selecting underachievers, but nomination selected a different group of underachievers. It was suggested that, depending on research or intervention purposes, information from statistical methods and nomination might combine to provide a more comprehensive identification procedure.

Effects of simple and regressed discrepancy models and cutoffs on severe discrepancy determination

Concern over the growing number of students identified as learning disabled has led school districts to examine the criteria for determination and the means by which they are operationalized. Two frequently used methods for determining a severe discrepancy between ability and achievement, a key criterion in LD determination, were applied to a sample of 344 students to determine how a change in method might influence the rates and characteristics of students meeting this criterion. The results indicate an increase in numbers when a regression method is used over a simple difference score method. When the change proposed included moving to a more severe cutoff score, the pattern reversed and a 20% decrease was observed. Although IQ correlated with the discrepancies when the simple difference score method was used, no correlation was observed when regression was employed, indicating that regression may be a more equitable method for calculating severe discrepancies. Neither method resulted in disproportionate racial representation among those meeting the severe discrepancy criterion.

The “isolated” popliteal segment: A comparative evaluation of its vascular resistance

During femoro-popliteal and femoro-distal bypass, measurement of vascular resistance (VR) at the site of graft outflow may be used to quantify "run off". Intra-operative measurements were made in 51 lower limbs to compare VR in different categories of outflow; the "isolated" popliteal segment (IPS group, n = 11), the popliteal artery in continuity with patent vessels to the pedal arch (PIC group, n = 26) and the single calf vessel (SCV group, n = 14). VR was measured both before and after intra-arterial papaverine. The values in the 37 popliteal arteries were correlated with two different methods of arteriographic scoring. Vascular resistance in the IPS group (median 1149 mPRU, P = 0.003) but not significantly different from VR in the SCV group (median 1014 mPRU, range 743-1541 mPRU). VR in the SCV group was significantly greater than that in the PIC group (P = 0.006). After papaverine administration, the same relationships were observed between the IPS, PIC and SCV groups. Both before and after papaverine, VR in the popliteal artery correlated significantly with both arteriographic scores. In terms of VR, the isolated popliteal segment provides an outflow comparable to that of a single calf artery but less favourable than a popliteal artery wtih patent run off.

Besonderheiten des Schlafes bei abstinenten Alkoholikern Vergleich alkohol- und alterungsbedingter Tiefschlafreduktion

Polygraphic sleep recordings were performed in 12 sober alcoholic patients, 8 young normals and 12 healthy elderly subjects. An automatic sleep analysis including two different methods (standard and adaptive) of SWS scoring was used