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PubMed1995

When comparisons arise.

People acquire information about their abilities by comparison, and research suggests that people restrict such comparisons to those whom they consider sources of diagnostic information. We suggest that diagnosticity is often considered only after comparisons are made and that people do not fail to make nondiagnostic comparisons so much as they mentally undo them. In 2 studies, participants made nondiagnostic comparisons even when they knew they should not, and quickly unmade them when they were able. These results suggest that social comparisons may be relatively spontaneous, effortless, and unintentional reactions to the performances of others and that they may occur even when people consider such reactions logically inappropriate.

Affect↗

PubMed2004

Feeling better about doing worse: social comparisons within romantic relationships.

The authors examined the role of closeness between self and partner in determining the impact of social comparisons within intimate relationships. To the extent that one's partner is a central aspect of one's identity, one may be able to restore one's positive self-regard following an upward comparison with the partner by turning to the relationship as a self-affirmational resource. Studies 1 and 2 examined reactions to imagined comparisons; Studies 3 and 4 examined reactions to actual comparison feedback. Across studies, closeness moderated the impact of upward comparisons with the partner; that is, higher closeness participants responded to a more successful partner by focusing on their relationship-related strengths. However, closeness did not moderate the impact of downward comparisons with the partner.

Adult↗

PubMed2004

The ups and downs of social comparison: mechanisms of assimilation and contrast.

Social comparisons influence self-evaluations in multiple ways. Sometimes self-evaluations are assimilated toward a given standard. At other times, they are contrasted away from the standard. On the basis of the selective accessibility model (T. Mussweiler, 2003a), the authors hypothesized that assimilation results if judges engage in the comparison process of similarity testing and selectively focus on similarities to the standard, whereas contrast occurs if judges engage in dissimilarity testing and selectively focus on differences. If these alternative comparison mechanisms are indeed at play, then assimilative and contrastive social comparisons should be accompanied by diverging informational foci on similarities versus differences. Results of 5 studies support this reasoning, demonstrating that assimilation results under conditions that foster similarity testing, whereas contrast occurs under conditions that foster dissimilarity testing. Furthermore, assimilative social comparisons are accompanied by a general informational focus on similarities, whereas contrastive comparisons are accompanied by a focus on differences.

Competitive Behavior↗

PubMed2004

Method matters: effects of explicit versus implicit social comparisons on activation, behavior, and self-views.

The authors investigated the impact of explicit versus implicit social comparisons. Simply being primed with a superior or inferior standard (implicit comparison) produced contrast as evidenced by accessibility of self-knowledge (Study 2), intellectual performance (Study 3), and self-ratings (Study 4), inconsistent with the standard. However, when participants were explicitly asked to compare, increased accessibility of a similarity focus (Study 1) and self-knowledge, behavioral performance, and self-ratings congruent with the standard were obtained more easily, indicative of assimilation. Explicit comparisons produced assimilation when the self was seen as mutable (rather than immutable; Study 4), when behavioral consequences were measured immediately after the comparison (rather than later; Study 3), and when the participants described (rather than ranked) their intelligence (Study 5). These findings support the interpretation comparison model. Implications for resolution of empirical inconsistencies in the social comparison literature are discussed.

Adult↗

PubMed2002

A randomized paired comparison trial of cutaneous treatments for acute jellyfish (Carybdea alata) stings.

The objective of the study was to compare cutaneous treatments (heat, papain and vinegar) for acute jellyfish (Carybdea alata) stings. Healthy adult volunteer subjects received a single-tentacle jellyfish sting on each forearm. One forearm was treated with hot-water immersion (40-41 degrees C). This was compared with the other forearm, which was randomized to a comparison treatment of papain meat tenderizer or vinegar. Pain was measured at 0, 2, 4, 6, 8, 10, 15, and 20 minutes using a 10-cm visual analog scale (VAS). For 25 subject runs, the average VAS scores at t = 0 were 3.6 cm (hot water) and 3.7 cm (comparison treatment). At t = 4 minutes (2 minutes after treatment had started), the differences between hot-water and comparison group VAS scores were 2.1 cm versus 3.2 cm, respectively. The mean difference between hot-water and comparison treatments was 1.1 cm (95% confidence interval, 0.6 to 1.6). At t = 20 minutes (the end of the study period), the differences between hot-water and comparison group VAS scores were 0.2 cm versus 1.8 cm, respectively. The mean difference between hot-water and comparison treatments was 1.6 cm (95% confidence interval, 0.9 to 2.3). This study suggests that the most efficacious initial treatment for C alata jellyfish envenomation is hot-water immersion to the afflicted site.

Acetic Acid↗

PubMed2001

Comparison of the effects of two early intervention strategies on the health outcomes of malnourished hemodialysis patients.

OBJECTIVE: To determine the efficacy and cost-effectiveness of providing oral supplementation early in the course of malnutrition for hemodialysis (HD) patients. DESIGN: The study design consisted of 3 groups: an experimental group, a control group of patients with mild hypoalbuminemia (HA) (serum albumin [SA] = 3.5 to 3.7 g/dL), and a comparison group of patients with moderate to severe HA (SA = 2.5 to 3.4 g/dL). SETTING: Ten outpatient hemodialysis centers in southeast lower Michigan. PATIENTS: Treatment and control groups consisted of 32 HD patients with mild HA. Fourteen HD patients with moderate to severe HA comprised the comparison group. INTERVENTION: The experimental group received diet counseling and oral supplementation, and the control group received diet counseling only. The comparison group received physician-prescribed oral supplements and dietary counseling to permit comparison of the experimental treatment with current supplementation practices. MAIN OUTCOME MEASURES: Differences between groups in the number of patients reaching nutritional repletion, change in SA levels at the end of the study, and follow-up periods, were tested using chi-square analysis. Analysis of variance was used to compare group differences in treatment duration to repletion and number of hospitalization days. RESULTS: During the study period, significantly more patients reached nutritional repletion in the experimental group and control group (50% and 57%, respectively) than in the comparison group (7%). Overall, repletion occurred more quickly in the experimental group (3.2 +/- 1.7 months) than in the control group (3.5 +/- 1.2 months), with a larger number of patients in the experimental group repleted by month 2 of the study phase. During follow-up, patients in the experimental group were far more likely to maintain nutritional repletion or continue to improve (61%) than patients in the control group (14%). Although too few patients were hospitalized to show statistical significance, there was a trend toward greater numbers of hospital days in more malnourished patients (208 days for the comparison group), followed by those with mild HA who did not receive oral supplements (107 days), and the experimental group (71 days). CONCLUSION: Although the sample size for this study was too small for the results to be conclusive, it appears that use of nutritional supplements early in the course of malnutrition may provide benefits such as, attaining nutritional repletion more quickly, which results in less product usage. It is also more likely that good nutritional status will be maintained after supplementation is discontinued.

Aged↗

PubMed2006

Exploring the use of social comparison by individuals recovering from traumatic brain injury.

OBJECTIVE: To explore if and how individuals with traumatic brain injury (TBI) use social comparison during adjustment to disability. It was hypothesized that comparison activity may change with time since injury. METHODS: Fifty-eight participants with TBI were surveyed within 1 or 6 months of discharge from inpatient rehabilitation. Group responses to instruments measuring social comparison and other measures of emotional and physical functioning were compared. RESULTS: Both groups expressed a need for social comparison at a rate comparable to non-clinical populations. The group surveyed at 6 months expressed a greater need for social comparison and scored lower on a measure of mental health, as compared to the group surveyed earlier. CONCLUSIONS: Individuals with TBI appear to successfully use social comparison, at least early in recovery, with a possible reduction in effectiveness of use with increased time from injury. Possible mediating factors and implications for adjustment and future study are discussed.

Adaptation, Psychological↗

PubMed2006

On dose distribution comparison.

In radiotherapy practice, one often needs to compare two dose distributions. Especially with the wide clinical implementation of intensity-modulated radiation therapy, software tools for quantitative dose (or fluence) distribution comparison are required for patient-specific quality assurance. Dose distribution comparison is not a trivial task since it has to be performed in both dose and spatial domains in order to be clinically relevant. Each of the existing comparison methods has its own strengths and weaknesses and there is room for improvement. In this work, we developed a general framework for comparing dose distributions. Using a new concept called maximum allowed dose difference (MADD), the comparison in both dose and spatial domains can be performed entirely in the dose domain. Formulae for calculating MADD values for various comparison methods, such as composite analysis and gamma index, have been derived. For convenience in clinical practice, a new measure called normalized dose difference (NDD) has also been proposed, which is the dose difference at a point scaled by the ratio of MADD to the predetermined dose acceptance tolerance. Unlike the simple dose difference test, NDD works in both low and high dose gradient regions because it considers both dose and spatial acceptance tolerances through MADD. The new method has been applied to a test case and a clinical example. It was found that the new method combines the merits of the existing methods (accurate, simple, clinically intuitive and insensitive to dose grid size) and can easily be implemented into any dose/intensity comparison tool.

Algorithms↗

PubMed1992

Dynamic programming algorithms for restriction map comparison.

For most sequence comparison problems there is a corresponding map comparison algorithm. While map data may appear to be incompatible with dynamic programming, we show in this paper that the rigor and efficiency of dynamic programming algorithms carry over to the map comparison algorithms. We present algorithms for restriction map comparison that deal with two types of map errors: (i) closely spaced sites for different enzymes can be ordered incorrectly, and (ii) closely spaced sites for the same enzyme can be mapped as a single site. The new algorithms are a natural extension of a previous map comparison model. Dynamic programming algorithms for computing optimal global and local alignments under the new model are described. The new algorithms take about the same order of time as previous map comparison algorithms. Programs implementing some of the new algorithms are used to find similar regions within the Escherichia coli restriction map of Kohara et al.

Algorithms↗

PubMed1986

Calf blood flow and vascular resistance in borderline hypertensives in comparison with control subjects.

A significant reduction of maximal vasodilation capacity at the calf in relation to the severity of the hypertensive state has been demonstrated in essential hypertension. The aim of this study was to evaluate the behavior of calf blood flow and vascular resistance in borderline hypertensives (BH) in comparison with normotensive control subjects (CS). We studied 32 BH, with average age of 47.31 +/- 16.78 years and blood pressure 140-160/90-95 mm/Hg, in comparison with 20 CS, with average age of 47.24 +/- 11.75 years and blood pressure values below 140/85 mm Hg. Calf rest flow (RF) and peak flow (PF) were evaluated by strain-gauge plethysmography, and basal vascular resistance (BVR) and minimal vascular resistance (MVR) were calculated by the ratio between mean blood pressure and RF and PF, respectively. Mean blood pressure was significantly higher in BH in comparison with CS. RF and PF did not differ significantly in BH in comparison with CS. BVR did not differ in BHs in comparison with CS. In contrast, MVR were significantly higher in BH in comparison with CS. These results show that in BH, arterial flow at the calf is normal, whereas MVR are higher, indicating an impairment of maximal vasodilation capacity despite the modest blood pressure elevation.

Adult↗

PubMed2006

Can Florida become like the next Florida? When metaphoric comparisons fail.

Metaphors can be understood in either of two ways: via a comparison process or via a categorization process. What determines which process will be used? According to a recent variant of comparison theory, novel metaphors must be processed as comparisons; only conventional metaphors can be processed as categorizations. We argue that choice of process is determined not by conventionality, but instead by the semantic and referential properties of the metaphor itself. We identified a type of novel metaphor that is indeed understood more quickly as a comparison than as a categorization. We then generated variants of such metaphors to make comparison difficult and found that these new novel metaphors were understood more quickly as categorizations than as comparisons. We conclude that metaphors can be processed as categorizations from the start, depending on their semantic and referential properties.

Comprehension↗

PubMed2003

Comparison of model selection for regression.

We discuss empirical comparison of analytical methods for model selection. Currently, there is no consensus on the best method for finite-sample estimation problems, even for the simple case of linear estimators. This article presents empirical comparisons between classical statistical methods - Akaike information criterion (AIC) and Bayesian information criterion (BIC) - and the structural risk minimization (SRM) method, based on Vapnik-Chervonenkis (VC) theory, for regression problems. Our study is motivated by empirical comparisons in Hastie, Tibshirani, and Friedman (2001), which claims that the SRM method performs poorly for model selection and suggests that AIC yields superior predictive performance. Hence, we present empirical comparisons for various data sets and different types of estimators (linear, subset selection, and k-nearest neighbor regression). Our results demonstrate the practical advantages of VC-based model selection; it consistently outperforms AIC for all data sets. In our study, SRM and BIC methods show similar predictive performance. This discrepancy (between empirical results obtained using the same data) is caused by methodological drawbacks in Hastie et al. (2001), especially in their loose interpretation and application of SRM method. Hence, we discuss methodological issues important for meaningful comparisons and practical application of SRM method. We also point out the importance of accurate estimation of model complexity (VC-dimension) for empirical comparisons and propose a new practical estimate of model complexity for k-nearest neighbors regression.

Bayes Theorem↗

PubMed2006

Frontal functions in young patients with essential tremor: a case comparison study.

Essential tremor (ET) is classified as a pure motor system disease. It has been previously reported that impairments in cognitive functions can be associated with ET. The authors assessed cognitive functions in a relatively young patient group with ET and comparison subjects. Correlations between tremor severity and regional cerebral blood flow (rCBF) and neuropsychological test performances of ET patients and comparison subjects were investigated. Sixteen patients with ET and 16 comparison subjects were assessed by a comprehensive neuropsychological test battery designed to assess global attention, language, memory, visuospatial functions, and executive functions. In 11 of 16 patients and in nine of 16 comparison subjects, rCBF was measured by technetium-99m-hexamethyl propylene amine oxime single photon emission computed tomography (technetium-99m-HMPAO SPECT). The tremor severity was quantified using the Clinical Rating Scale for Tremor (CRST). Findings revealed that ET patients differed significantly from comparison subjects on tests assessing visuospatial functions and verbal memory, whereas differences in other tests did not reach statistical significance. There was no significant difference between the rCBF of ET patients and comparison subjects. There were statistically significant inverse correlations between tremor severity and executive functions. Tremor severity was inversely correlated with bilateral frontal blood flow by technetium-99m-HMPAO SPECT. Conclusions suggest that the subclinical cognitive deficits characterized by visuospatial and verbal memory impairments and executive dysfunction may be a clinical feature of ET, and the cerebello-thalamo-frontal network may play a role in the pathophysiology of this disorder.

Adolescent↗

PubMed2006

Social comparison processes in autobiographies of adult cancer survivors.

Cancer survivors often compare their situations to other survivors' situations. However, types of social comparison processes used and resulting outcomes are not clearly delineated. This study explores usage and consequences of three social comparison styles (downward, upward and parallel) of adult cancer survivors in free narratives, using content analysis of 30 autobiographical books by survivors ranging in age from 30-70 (M = 54, SD = 10.04); 43 percent prostate cancer, 17 percent breast cancer and 40 percent other cancers. Overall, cancer survivors used more parallel comparisons than directional comparisons, followed by upward comparisons. Each type of comparison was associated with different kinds of positive and negative consequences.

Adaptation, Psychological↗

PubMed2006

inGeno--an integrated genome and ortholog viewer for improved genome to genome comparisons.

BACKGROUND: Systematic genome comparisons are an important tool to reveal gene functions, pathogenic features, metabolic pathways and genome evolution in the era of post-genomics. Furthermore, such comparisons provide important clues for vaccines and drug development. Existing genome comparison software often lacks accurate information on orthologs, the function of similar genes identified and genome-wide reports and lists on specific functions. All these features and further analyses are provided here in the context of a modular software tool "inGeno" written in Java with Biojava subroutines. RESULTS: InGeno provides a user-friendly interactive visualization platform for sequence comparisons (comprehensive reciprocal protein--protein comparisons) between complete genome sequences and all associated annotations and features. The comparison data can be acquired from several different sequence analysis programs in flexible formats. Automatic dot-plot analysis includes output reduction, filtering, ortholog testing and linear regression, followed by smart clustering (local collinear blocks; LCBs) to reveal similar genome regions. Further, the system provides genome alignment and visualization editor, collinear relationships and strain-specific islands. Specific annotations and functions are parsed, recognized, clustered, logically concatenated and visualized and summarized in reports. CONCLUSION: As shown in this study, inGeno can be applied to study and compare in particular prokaryotic genomes against each other (gram positive and negative as well as close and more distantly related species) and has been proven to be sensitive and accurate. This modular software is user-friendly and easily accommodates new routines to meet specific user-defined requirements.

Base Sequence↗

PubMed2006

Duloxetine compared with fluoxetine and venlafaxine: use of meta-regression analysis for indirect comparisons.

BACKGROUND: Data comparing duloxetine with existing antidepressant treatments is limited. A comparison of duloxetine with fluoxetine has been performed but no comparison with venlafaxine, the other antidepressant in the same therapeutic class with a significant market share, has been undertaken. In the absence of relevant data to assess the place that duloxetine should occupy in the therapeutic arsenal, indirect comparisons are the most rigorous way to go. We conducted a systematic review of the efficacy of duloxetine, fluoxetine and venlafaxine versus placebo in the treatment of Major Depressive Disorder (MDD), and performed indirect comparisons through meta-regressions. METHODS: The bibliography of the Agency for Health Care Policy and Research and the CENTRAL, Medline, and Embase databases were interrogated using advanced search strategies based on a combination of text and index terms. The search focused on randomized placebo-controlled clinical trials involving adult patients treated for acute phase Major Depressive Disorder. All outcomes were derived to take account for varying placebo responses throughout studies. Primary outcome was treatment efficacy as measured by Hedge's g effect size. Secondary outcomes were response and dropout rates as measured by log odds ratios. Meta-regressions were run to indirectly compare the drugs. Sensitivity analysis, assessing the influence of individual studies over the results, and the influence of patients' characteristics were run. RESULTS: 22 studies involving fluoxetine, 9 involving duloxetine and 8 involving venlafaxine were selected. Using indirect comparison methodology, estimated effect sizes for efficacy compared with duloxetine were 0.11 [-0.14;0.36] for fluoxetine and 0.22 [0.06;0.38] for venlafaxine. Response log odds ratios were -0.21 [-0.44;0.03], 0.70 [0.26;1.14]. Dropout log odds ratios were -0.02 [-0.33;0.29], 0.21 [-0.13;0.55]. Sensitivity analyses showed that results were consistent. CONCLUSION: Fluoxetine was not statistically different in either tolerability or efficacy when compared with duloxetine. Venlafaxine was significantly superior to duloxetine in all analyses except dropout rate. In the absence of relevant data from head-to-head comparison trials, results suggest that venlafaxine is superior compared with duloxetine and that duloxetine does not differentiate from fluoxetine.

Antidepressive Agents↗

PubMed2007

Detection of weakly conserved ancestral mammalian regulatory sequences by primate comparisons.

BACKGROUND: Genomic comparisons between human and distant, non-primate mammals are commonly used to identify cis-regulatory elements based on constrained sequence evolution. However, these methods fail to detect functional elements that are too weakly conserved among mammals to distinguish them from non-functional DNA. RESULTS: To evaluate a strategy for large scale genome annotation that is complementary to the commonly used distal species comparisons, we explored the potential of deep intra-primate sequence comparisons. We sequenced the orthologs of 558 kb of human genomic sequence, covering multiple loci involved in cholesterol homeostasis, in 6 non-human primates. Our analysis identified six non-coding DNA elements displaying significant conservation among primates but undetectable in more distant comparisons. In vitro and in vivo tests revealed that at least three of these six elements have regulatory function. Notably, the mouse orthologs of these three functional human sequences had regulatory activity despite their lack of significant sequence conservation, indicating that they are ancestral mammalian cis-regulatory elements. These regulatory elements could be detected even in a smaller set of three primate species including human, rhesus and marmoset. CONCLUSION: We have demonstrated that intra-primate sequence comparisons can be used to identify functional modules in large genomic regions, including cis-regulatory elements that are not detectable through comparison with non-mammalian genomes. With the available human and rhesus genomes and that of marmoset, which is being actively sequenced, this strategy can be extended to the whole genome in the near future.

Animals↗

PubMed2002

The social behaviors and peer expectation of girls with attention deficit hyperactivity disorder and comparison girls.

Investigated self-described social goals, self-generated actions, and perceived peer responses to hypothetical vignettes, as well as observed social behavior and peer sociometric status, in an ethnically and socioeconomically diverse sample of girls with attention deficit hyperactivity disorder (ADHD; n = 49) and comparison girls (n = 30). Although we found no differences between the social goals of girls with ADHD and comparison participants, girls with ADHD generated higher rates of aggressive responses to the hypothetical vignettes than did comparison girls, whereas comparison girls generated a larger number of negotiating behaviors than did the ADHD sample. The ADHD participants anticipated negative peer responses, whereas comparison girls predicted positive reactions from peers. Importantly, these perceived peer responses showed associations with girls' naturalistic social behaviors and peer sociometric status. Several pertinent predictions held with control of ADHD versus comparison status. Social cognitions appear to be relevant in the investigation of ADHD in girls.

Attention Deficit Disorder with Hyperactivity↗