Dichotomous Scale Research Articles

Measuring the Perception of Choices in the Nursing Home

The purpose of this study was to measure the perception of choices among elders who live in a nursing home. The perception of choices, defined as a subjective appraisal of alternatives as understood by the individual, includes the freedom to make decisions, individuality of judgment, and availability of options. The instrument--Perception of Choices in a Nursing Home (PCL)--is a 10-item dichotomous scale designed for administration to frail elderly. A study with three phases involved 228 elderly in 19 different nursing homes. The results of principal component's factor analysis supported the presence of one dimension interpreted as having choices. The internal consistency reliability was a = .84, n = 99; and a = .74, n = 129. Low mental status did not affect internal consistency reliability but affected retest reliability, r = 67. The PCL correlated significantly with depression, r = .31, p = .0001, and powerlessness, .36, p = .005.

Statistical Implications of the Choice between a Dichotomous or Continuous Trait in Studies of Interobserver Agreement

A frequently occurring question in the planning of studies is whether to measure the trait of interest on a continuous or dichotomous scale. An issue potentially relevant to this question centers around the resulting reliability of the measure. Assuming the continuous trait has a normal distribution, we quantify the effect of this decision on the overall number of subjects required to test whether a population reliability coefficient equals a specified criterion value. Two distinct cases are explored: the choice between a continuous response and a truly dichotomous response, and the case in which an inherently continuous response is dichotomized. In both cases, and particularly in the second, the loss of power associated with measuring the trait on a dichotomous scale is shown to be always severe and frequently prohibitive.

Factors that contribute to the reduced weight gain following chronic ventromedial hypothalamic stimulation

This report follows up our earlier finding that chronic ventromedial hypothalamic stimulation caused an inhibition of weight gain. In this study we examined the contribution of stimulation-induced activity and brown adipose tissue thermogenesis to the reduced weight gain following three sessions of low-level stimulation delivered every other day to the ventromedial hypothalamus and adjacent areas. During stimulation trials, activity level was ranked on a dichotomous scale. Weight gain and food intake were subsequently monitored for an additional 4 weeks, after which the effects of a 60-s stimulation trial on the temperature of core and interscapular brown adipose tissue were evaluated. The highest activity was associated with the ventromedial hypothalamic sites and this factor contributed significantly to the difference in weight gain and food intake resulting from stimulation of the ventromedial hypothalamus and other areas. These differences largely disappeared during the follow-up period. With little exception, none of the sites elicited temperature changes in brown adipose tissue. As demonstrated in acute work, the contribution of stimulation-induced activity must be dissociated from the metabolic changes that occur in response to ventromedial hypothalmic stimulation.

Assessment of insight in psychosis.

It is frequently reported that patients with psychotic disorders have poor insight into their illness. Previous research has suggested that poor insight may have considerable power in predicting the long-term course of chronic mental disorders and an impact on patients' compliance with treatment plans. The authors, proposing that insight is best viewed as a multidimensional phenomenon, developed the Scale to Assess Unawareness of Mental Disorder, which samples discrete and global aspects of insight across a variety of manifestations of illness. This article reports on a reliability and validity study of the scale. The study subjects were 43 patients with schizophrenia and schizoaffective disorder. Various aspects of insight into illness were evaluated with the scale. In addition, ratings of psychopathology, course of illness, and compliance with treatment were made. Item variability was high and normally distributed, supporting the authors' contention that insight can be rated on a continuous rather than dichotomous scale. Results of the analyses examining the relations between the various dimensions of insight assessed and the psychopathology, course, and compliance variables were generally as hypothesized. Convergent validity with other global measures of insight was found, and aspects of poor insight were correlated with poorer compliance and course of illness. Examination of the interrelations among the four insight subscales revealed that these subscales sample independent phenomena. The Scale to Assess Unawareness of Mental Disorder has good reliability and validity and has certain advantages over previous measures of insight, suggesting the usefulness of a multidimensional view of this complex concept.

Interval Estimation under Two Study Designs for Kappa with Binary Classifications

Cornfield's test-based method of setting a confidence interval on a parameter associated with a two-by-two contingency table is adapted for use with the measure of agreement kappa. One-sided confidence intervals derived in this way are compared to other intervals proposed for kappa under two study designs. Both designs involve two ratings per subject on a dichotomous scale. In one design the same two raters make all evaluations; in the other, possibly different pairs of raters evaluate different subjects, or the same rater carries out a pair of independent assessments for each subject. It is shown through simulation that lower bounds based on Cornfield's test-based method attain the nominal coverage probability more often than other intervals proposed in the literature.

Nerve excitability testing: technical pitfalls and threshold norms using absolute values.

Percutaneous stimulation of the facial nerve is used widely in tests to judge the severity and prognosis of facial paralysis. Several test paradigms are used including nerve excitability threshold (NET), the maximum stimulation test (MST), and electroneuronography (EnoG). Consistent technique and careful control of variables are essential to achieve accurate test results. The sources of variability examined in this study were age, gender, body weight, and the use of electrode paste; the NET was used as the test method. The facial NET in 120 adults without a history of facial paralysis increased linearly with age (P = .0004) and with body weight (P < .0001) and was higher in men than in women adjusted for age and weight (P = .0001). The mean NET +/- SD was 0.7 +/- 0.27 mA in the upper division using the eyelid twitch as an end point, and 1.2 +/- 0.40 mA in the lower division. There was no statistically significant difference in the results between sides. The NET was falsely elevated by the use of electrode paste, presumably due to current shunting away from the nerve. Based on the technique described herein, an absolute NET of > or = 1.25 mA in the upper division or an absolute NET > or = 2.0 mA in the lower division of the human facial nerve is statistically abnormal. These norms are not applicable to grossly obese patients or patients with facial edema or inflammation. Statistical norms allow the NET results to be reported on a continuous scale rather than the dichotomous scale used in the past. The predictive power of the NET will be greatly enhanced by basing test interpretation on both statistical and clinical significance.

Department of Veterans Affairs Cooperative Studies Project number 147: level of examiner reliability over seven years.

In 1980 the Veterans Administration Cooperative Studies Program No. 147 initiated a multicenter, multidisciplinary clinical study to evaluate the use of alternative alloys for porcelain-fused-to-metal restorations. An investigation of interexaminer agreement was conducted after seven years utilizing three measures of reliability: percentage of exact agreement using a five-point scale, percentage of agreement using a dichotomous (satisfactory-unsatisfactory) scale, and [kappa], a statistic which is intended to measure agreement beyond what would be expected to occur by chance. Exact agreement on the five-point scale ranged from 77 to 99 percent. Percent agreement on the dichotomous scale was above 99 percent for all of the criteria. Kappa ranged from 0.56 to 0.91, indicating moderate to near perfect agreement among examiners. Reliability of the study evaluations reinforced the validity and significance of the findings.

Scales for assessing perceptions of health hazard susceptibility.

Two studies examined the effectiveness of a variety of commonly used likelihood scales (dichotomous scale, five-point verbally-labeled scale, odds scale, percentage scale, etc.) for assessing perceptions of personal susceptibility to health and safety risks. Two direct evaluation criteria (subjects' ratings of how easy it was to use a scale and of how well the scale reflected their feelings) and three additional measures of validity and reliability (the agreement of scale-derived ranks with a direct ranking, the magnitude of correlations between risk perceptions and appropriate risk factors, and the stability of scores over time) were used to compare the scales. Increasing the number of scale categories did not necessarily improve performance. In fact, a scale with seven verbally-labeled categories performed as well as or better than other scales on all evaluation criteria. These data may help health education researchers in selecting scales to measure perceptions of susceptibility to harm.

Educational Level and Professional Activities of Occupational Therapists: A Case Study

Alumni of the three educational tracks of the University of Southern California were surveyed to examine the influence of level and type of educational preparation on professional activities. The entry-level and postprofessional master's groups scored higher than the baccalaureate group in 6 of 10 activity categories investigated—education, leadership, administration and supervision, oral presentations, publications, and research. The entry-level master's group differed from the postprofessional master's group only in education, leadership, and professional recognition. The results confirm that programmatic differences between basic and advanced professional education yield different outcomes in terms of involvement in professional activities. They also suggest that some activity categories are more amenable to educational influences than others. Limitations of the study include use of a self-report instrument, reliance on a dichotomous scale involving only activity participation and non-participation, and consideration of the influence of education on professional activities in isolation from other factors known to influence involvement.

A quality assessment system: the search for validity

Quality assessment and assurance should involve all of dentistry, not just third party payment plans. One evaluation system is described and a draft outline of guidelines for criteria and standards is presented. An important, and usually neglected, aspect of the use of the system is illustrated by the presentation of some quantitative data from the review of a dental care program. Concerns about the validity of various elements are discussed, together with the difficulty of establishing such validity. Nevertheless, there are indications that the system is able to distinguish among different levels of quality using a dichotomous scale. More research in the field is urged.

Ibuprofen and Acetaminophen in the Relief of Acute Pain: A Randomized, Double‐Blind, Placebo‐Controlled Study

To determine the relative analgesic efficacy of ibuprofen 400 mg and acetaminophen 1000 mg, we conducted a single-dose, double-blind, placebo-controlled, randomized clinical trial using a standard assay for analgesic agents, the dental pain model. At regular intervals over 6 hours, 184 patients who had undergone dental impaction surgery rated pain intensity and relief on categorical scales and pain half-gone on a dichotomous nominal scale; a categorical overall evaluation was completed at the end of 6 hours. Both active agents were effective compared to placebo. Ibuprofen 400 mg was more effective than acetaminophen 1000 mg for Sum Pain Intensity Difference (SPID), Total Pain Relief (TOTPAR), sum pain half-gone, and overall evaluation (P less than .05 to P less than .001). The time-effect curves demonstrated a greater peak effect and longer duration of action for ibuprofen 400 mg compared to acetaminophen 1000 mg. Side effects were reported in five ibuprofen patients, 11 acetaminophen-treated patients, and seven placebo patients. Based on the results of this clinical study, we conclude that ibuprofen 400 mg is a safe and more effective analgesic than acetaminophen 1000 mg for patients with acute pain.

順序性をもつデータ構造と因子分析

A Γ-shaped scatter diagram of factor scores has been reported previously in common with the data relating to cerebral and neural diseases; language tests of aphasia, finger function tests of hemiplegia, and symptoms in mild disturbance of consciousness. The factors were inter pretable as situated successively on severity continuum of the diseases. Scale analysis suggested a data structure based on Guttman perfect scale. Then Guttman perfect scale and quasi-scale models were investigated in respect to attributes of correlation matrices of dichotomous scale variables. Eigenvalues and eigenvectors were obtained in case of the perfect scale that subjects had a uniform distribution on the continuum. According to the number of eigenvalues greater than 1, the number of factors is expected as √t-½in the perfect scale, where t is the number of variables. The score of the 2-nd factor before factor rotation is represented by a parabola of the 1-st factor. The oscillation law of eigenvectors has a characteristic manifestation on the factor loadings after rotation, and on the Γ-shaped distribution of factor scores. Successive factors have high loadings on successive groups of variables located in the order determined by Guttman scale. In quasi-scale models, these properties undergo certain changes, so that the Γ-shape becomes ambiguous depending on the size of deviation from the perfect scale.

An Improvement Over Guttman Scalogram Analysis: A Computer Program for Evaluating Cumulative, Nonparametric Scales of Dichotomous Items

This article mentions some of the problems associated with the criteria of reproducibility and scalability as they are commonly used in Guttman scalogram analysis to evaluate cumulative, non-parametric scales of dichotomous items. It then describes the advantages of criteria developed by Loevinger (1948) and Mokken (1971) to evaluate such scales. A short SAS computer program is presented which analyzes response patterns elicited by dichotomous scales designed to be cumulative. The program computes Loevinger's H as index of the scalability (cumulativeness) of a set of items as well as Mokken's Hi for each item indicating the degree of scalability of each item with respect to the other items of a given scale.

Measuring disability—Do self-ratings and service provider ratings compare?

The assessment of disability in open care is often made by questionnaire-based ratings. In using such ratings, researchers should be aware of the similarities and differences between these criteria and those used by the health care personnel. This report shows that the level of agreement between the questionnaire-based and the provider ratings was not very high for housework. In using dichotomous scales, the overall percentage of cases in which there was matching was 77% for cooking activity and 64% for cleaning activity. The levels of agreement between the questionnaire-based and the provider ratings were high for the more basic self-care activities. In using quadritomous scales, the percentage of cases in which there was total agreement between these two measurements were 94–97% for the activities of dressing, eating and daily washing. The more complex self-care activities, i.e. bathing and sauna, showed a lower proportion of complete agreement than the three basic activities. The level of total agreement for bathing and sauna was 84%.

Dichotomous and Multipoint Scales Using Bipolar Adjectives

Subjects responded to a set of self-descnptive bipo lar adjectives in either a dichotomous format or a 7-point bipolar rating scale format. In addition, each subject answered a measure of social desirability re sponding rate The responses of over 400 subjects in each format were factor analyzed, followed by a vari max rotation The factor structure for the formats were strikingly similar and closely reflected the traits repre sented by the adjectives. Social desirability was found to be of minimal influence for either format. However, the factors derived from the multipoint format were slightly clearer and accounted for more variance. In addition, trait measures produced by the sum of four adjective scales from a common content dimension were more internally consistent using the multipoint format.

Easing the Process: A Strategy for Evaluating Compositions

Several years ago I resolved to devise a method of evaluating compositions which would actually help students learn to write rather than alienate or discourage them. What I came up with was an evaluative strategy enabling me to support students at critical points in the composing process: the pre-writing or thinking stage, the rough draft, the final draft, and the revision. My idea rested on the assumption that at each of these stages students face different problems, and that their successes in solving these problems need to be measured separately if they are to develop as writers. The four-part method of evaluation has been received enthusiastically by my students, and has enabled me to spend less time assigning grades and more time helping students to clarify and develop their thoughts. Evaluation, in other words, has become an integral part of teaching composition. To help students get a running start on composition, I require selfevaluation at the pre-writing and rough draft stage. Many students resist writing because they are unable to choose a subject, establish a thesis, discover ways of developing ideas and invent an audience. Self-evaluation helps them accomplish these tasks and bolsters confidence when it is most needed. A simple list of questions requiring a yes and no response (a dichotomous scale) serves for self-evaluation. Questions make the scale other than a merely prescriptive device; they engage the class in actively thinking about the relationship of writer to subject and audience. The scale is broken into two parts, each fitted to a different set of tasks (see A). The first part facilitates students' discovery of audience and topoi. The list of rhetorical methods, in particular, aids their memory, so that ideas generate other ideas. Then, after students have composed a rough draft, they evaluate its content and organization by responding to the second set of questions. To do this, they must empathize with their fictionalized audience and anticipate its needs. In so doing, they are more likely to be self-motivated than students who set out to please the instructor. Self-evaluation in the pre-writing and rough draft stages is thus designed to help students move from thought to expression.

A general caxedorical data memddology for evaluating medical diagnostic tests

Measures of sensitivity, predictive accuracy, and agreement are currently used to evaluate the efficiency of diagnostic tests reported on dichotomous scales. This paper presents a unified approach to the evaluation of diagnostic tests in terns of generalized Lnuices of sensitivity, misclassification, predictive accuracy and inaccuracy, classification agreement and prediction agreement for polytomous measurement scales. It Is sufficiently general to accommodate additional complications of study design factors such as multiple testing, known and unknown disease prevalence distributions, and multiple subpopulations defined by the cross-classification of independent factors. Estimation and hypothesis testing are developed within a general linear models approach to the analysis of categorical data from repeated measurement lesigns using weighted least squares computations. This methodology is illustrated within the context of data from a. large cotmiunity-based epidemiologic study of obstructive airways diseas...

Abusive and nonabusive parental treatment from the child's perspective.

Abusive and nonabusive parental treatment from the child's perspective.

Evaluating Student Multiple-Choice Responses

The effects of coded (type K) and free (type X) formats on student responses to identical multiple-choice items were com pared. Two subtests (A and B) each of 20 multiple-response items were emplo ved The items of the two subtests were placed in both K and X response formats pro ducing two examinations (i.e., exam I subtest A in type K format and subtest B in type X format; exam II. subtest A in type X format and subtest B in type K format) which were randomly distributed to 155 premedical students enrolled in an advanced human physiology course. Analyses of student performance led to four observanons. (1) the type K items significantly elevated student achievement scores due to a cueing effect inherent in the format, (2) the "poorer" students' scores were elevated more than the "better" students' scores, as evidence by a signifi cant negative relationship between the degree of cueing and examinee perfor mance; (3) the item format and scoring system (dichotomous or semicontinuous scales) affected the mean and variance of examinee scores; (4) the reliability (alpha coefficient) of items in the type X format tended to be statistically higher than that of items in the type K format. It was con cluded that an examination constructed in the type X format is a superior evalua tion instrument when compared to its parallel type K format

Comparison of different measurements of development of plaque and gingivitis in man

The purpose of the present study was to compare efficiency of measurements commonly used to study the development of plaque and gingivitis in short-term clinical trials. Data from a recent experiment on the effect of mutanase on accumulation of plaque and development of gingivitis were used. Efficiency was compared using 1) level of significance and 2) minimum number of individuals necessary to obtain a statistically significant result at a given level of significance and with a given power of the test. Of all the measurements used, the gingival exudate measurement was the most efficient. Among the nonparametric indices, Plaque Index was the most efficient, especially on proximal surfaces in the mandible. Reduction of the scales for the nonparametric indices from a four-point scale to a two-point (dichotomous) scale slightly reduced experimental efficiency.