Basic statistics and the inconsistency of multiple comparison procedures.

This paper has two main themes. First, the various statistical measures used in this journal are summarized and their interrelationships described by way of a flow chart. These are the pooled standard deviation, the pooled variance or mean square error (MSE), the standard error of each treatment mean (SEM) and of the difference between two treatment means (SED), and the least difference between two means which is significant at (e.g.) the 5% level of significance (LSD[5%]). The last three measures can be displayed as vertical bars in graphs, and the relationship between the lengths of these bars is graphically illustrated. It is suggested that the LSD is the most useful of these three measures. Second, when the experimenter has no prior hypotheses to be tested using analysis of variance "contrasts," a multiple comparison procedure (MCP) that examines all pair-wise differences between treatment means, may be appropriate. In this paper a fictitious experimental data set is used to compare several well-known MCPs by focussing on a particular operating known characteristic, the consistency of the results between an overall analysis of all treatments and an analysis of a subset of the experimental treatments... (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two modified procedures for estimating standard deviations in utility analyses.

F. L. Schimdt et al (see record 1981-02231-001) developed a procedure for obtaining rational estimates of the standard deviation of job performance in dollars (SDy). A problem in using their procedure is that it can yield large variation in percentile point estimates across judges. Two modified procedures using consensual feedback were tested with 26 high-level managers to determine if the new procedures could reduce this variability. The normality assumption of the utility estimates yielded by the Schmidt et al and modified procedures was also investigated, and SDy estimates from the Schmidt et al and 2 modified procedures were compared to each other and to a performance and salary distribution. Results indicate that one of the modified procedures offers an improved practical means of obtaining rational SDy estimates in utility analyses. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of three procedures for classifying addicts.

2 prevalent techniques plus a 3rd technique which compared individual to group profiles were employed to analyze the profiles of 2,179 narcotic addicts, using the Sixteen Personality Factor Questionnaire. It is concluded that inferences from classification studies can be related to the techniques used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tau protein. A potential biological indicator for early detection of Alzheimer disease]

C1311 is the most active member of a new series of rationally designed anti-cancer agents, the imidazoacridinones, which has shown promising pre-clinical anti-tumour activity in vitro and in vivo against a variety of human colon cancers and is a strong candidate for clinical trials. Data are not available on the pharmacokinetic properties of this compound; therefore, the main aim of this project was to study the plasma pharmacokinetics and tissue and tumour distribution of C1311 in mice and to assess, prior to potential clinical application, whether these pharmacokinetics were linear with respect to the dose. The distribution of C1311 in whole blood was also studied. NMRI or NCR-Nu mice were used throughout the study. C1311 was given i.p. at doses of 15, 50, 100 and (the maximum tolerated dose, (MTD) 150 mg kg(-l) i.p. Plasma, tissue and tumour levels were monitored over a 24-h period using high-performance liquid chromatography (HPLC) with fluorescence detection. The distribution of C1311 in murine and human whole blood was studied using both HPLC and fluorescence microscopy. C1311 was quickly cleared from the plasma (47410 ml min kg(-1)) and rapidly distributed into the tissues at all doses. Tissue-to-plasma ratios were large, ranging from 8 in the liver (15 mg kg(-l)) to 600 (50 mg kg(-1)) in the spleen. Overall concentrations were ranked in the order of plasma < liver < kidney < fat < small intestine < spleen. Tumour concentrations were similar to those measured in the liver and kidney, with AUCs being 186 (MAC15A) and 94.4 microg h ml(-l)(HT-29). Plasma pharmacokinetics were linear at doses of 15-100 mg kg(-1), but disproportionate increases were seen in plasma and tissue concentrations at doses above 100 mg kg(-l). C1311 distributed unevenly in both mouse and human blood, with higher concentrations occurring in the cellular fraction than in plasma. Nucleated cells accounted for a large proportion of this localised drug. In conclusion, C1311 is quickly cleared from the plasma and rapidly distributed into the tissues, with tissue concentrations being far higher than plasma levels. The plasma pharmacokinetics are linear up to but not above doses of 100 mg kg(-1). Concentrations of C1311 are greater in the cellular fraction of the blood than in the plasma, with disproportionately high concentrations occurring in the nucleated fraction.     

A comparison of two procedures for testing multiple contrasts.

Scheffe's test for contrasts is frequently used when a relatively small set of contrasts is of interest. When these contrasts have been planned prior to the data analysis, the Bonferroni t statistic provides a reasonable alternative. Comparisons are made of critical values for the 2 tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quality standard for antimicrobial prophylaxis in surgical procedures. Infectious Diseases Society of America

OBJECTIVE: The objectives of this quality standard are (1) to provide an implementation mechanism that will facilitate the reliable administration of prophylactic antimicrobial agents to patients undergoing operative procedures in which such a practice is judged to be beneficial and (2) to provide a guideline that will help local hospital committees formulate policies and set up mechanisms for their implementation. Although standards in the medical literature spell out recommendations for specific procedures, agents, schedules, and doses, other reports document that these standards frequently are not followed in practice. OPTIONS: We have specified the procedures in which the administration of prophylactic antimicrobial agents has been shown to be beneficial, those in which this practice is widely thought to be beneficial but in which compelling evidence is lacking, and those in which this practice is controversial. We have examined the evidence regarding the optimal timing of drug administration, the optimal dose, and the optimal duration of prophylaxis. OUTCOMES: The intended outcome is more uniform and reliable administration of prophylactic antibiotics in those circumstances where their value has been demonstrated or their use has been judged by the local practicing medical community to be desirable. The result should be a reduction in rates of postoperative wound infection in conjunction with a limitation on the quantities of antimicrobial agents used in circumstances where they are not likely to help. EVIDENCE: Many prospective, randomized, controlled trials comparing placebo with antibiotic and comparing one antibiotic with another have been conducted. In addition, some trials have compared the efficacy of different doses or methods of administration. Other papers have reported on the apparent efficacy of administration at different times and on actual practice in specific communities. Only a small group of relevant articles found through 1993 are cited herein. When authoritative reviews are available, these--rather than an exhaustive list of original references--are cited. VALUES: We assumed that reducing rates of postoperative infection was valuable but that reducing the total amount of antimicrobial agents employed was also worthwhile. The cost of and morbidity attributable to postoperative wound infections should be weighted against the cost and potential morbidity associated with excessive use of antimicrobial agents. BENEFITS, HARMS, AND COSTS: More reliable administration of antimicrobial agents according to recognized guidelines should prevent some postoperative wound infections while lowering the total quantity of these drugs used. No harms are anticipated. The costs involved are those of the efforts needed on a local basis to design and implement the mechanism that supports uniform and reliable administration of prophylactic antibiotics. RECOMMENDATIONS: All patients for whom prophylactic antimicrobial agents are recommended should receive them. The agents given should be appropriate in light of published guidelines. A short duration of prophylaxis (usually < 24 hours) is recommended. VALIDATION: More than 50 experts in infectious diseases and 10 experts in surgical infectious diseases and surgical subspecialties reviewed the standard. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Diseases Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (P.A.G. and J.E.M.), the Society for Hospital Epidemiology of America (R.P.W.), the Surgical Infection Society (E.P.D.), the Pediatric Infectious Diseases Society (P.J.K.), the Centers for Disease Control and Prevention (W.J.M.), the Obstetrics and Gynecology Infectious Diseases Society (R.L.S.), and the Association of Practitioners of Infection Control (T.     

A comparison of error in five sorting procedures for ordinal ranking.

The effect or sorting procedures on ranking error was investigated. Different groups of Ss ranked a series of 50 stimulus cards using 5 different sorting methods. Significant differences in ranking errors among the 5 methods were observed, with a "free" procedure showing less error than "structured" procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diagnostic tools for the detection of subclinical hepatic encephalopathy: comparison of standard and computerized psychometric tests with spectral-EEG

This study examined whether students' professional perceptions of interdisciplinary practice change following participation in a planned interdisciplinary experience in the rural setting, relative to their own profession and other health related disciplines. Data were collected from students enrolled in varied academic programs who participated in planned interdisciplinary experiences in the care of patients while in the clinical area through the Idaho Rural Interdisciplinary Training Project. Repeated measures multivariate and univariate analysis of variance revealed a significant change in students' perceptions of professional competence and autonomy of other disciplines and their own following the interdisciplinary experience in the clinical area. The data also revealed a significant change in students' perceptions at the completion of their clinical rotation of actual cooperation and resource sharing within and across professions. There was a significant gender effect and pretest to post-test effect following the interdisciplinary experience in the rural setting.     

A comparison of a token economy with standard inpatient treatment.

Used the Nurses Observation Scale for Inpatient Evaluation (NOSIE-30) to evaluate a token economy ward at a large psychiatric hospital in comparison with 3 nontoken wards in the same unit. The token economy appeared to be more effective in generating a broad range of behavior changes, including both an increase in positive behaviors and a decrease in negative behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of maximum likelihood with method of moment procedures for separating individual and group effects.

Monte Carlo simulations were used to compare the Kenny and La Voie (1985) method for separating individual and group effects with a maximum likelihood estimator. Maximum likelihood estimates cannot be out of bounds; that is, sample coefficients cannot be less than –2 or larger than +1. The Kenny and La Voie estimator yielded sample correlations greater than 200. The procedure used to attenuate the range and frequency of out-of-bounds occurrences was effective, but at the cost of making Type II errors. The 2 methods were shown to be similar in bias. Overall, the maximum likelihood estimator was judged preferable because it was always at least as good and sometimes better than the Kenny and La Voie method. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of commercially available kits with standard methods for detection of Salmonella strains in foods

Six commercial kits were compared with the U.S. Food and Drug Administration (USFDA) method and the Japanese standard method for Salmonella isolation in foods. When only Salmonella serovars were tested, many of the methods performed well; however, when foods were artificially inoculated, only the USFDA method and immunomagnetic separation coupled with the xylose-lysine-brilliant green agar method (MS-XLBG) could positively detect Salmonella serovars. All seven wild-type Salmonella serovars were detected by the USFDA method, and the MS-XLBG method detected salmonellae from six samples.     

Learning basic principles of probability in student dyads: A cross-age comparison.

Explored the effectiveness of the learning cell, or student dyad, for the acquisition of principles of probability in 46 5th graders, 35 9th graders, and 40 college undergraduates. Ss read about probability, then prepared study questions which they discussed with partners in 2 class periods. Scores on objective tests increased significantly for all age groups following reading and again following discussion. The learning cell was enjoyed most by 5th graders and least by 9th-grade boys, as measured by an evaluation questionnaire. Multiple regression analysis indicated that Ss' evaluations of the learning cell and of their discussion partners were unrelated to achievement. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of midazolam with propofol for sedation in outpatient bronchoscopy

Two children are described who had microphthalmia (one with unilateral and one with bilateral) noted at birth, and whose early onset of poor linear growth and weight gain led to a diagnosis of hypopituitarism prior to two years of age. Both children had growth hormone and thyroid-stimulating hormone deficiencies, and evidence of partial ACTH deficiency. Administration of growth hormone resulted not only in rapid linear growth but it also reversed the poor weight gain and head growth noted in these children. These cases suggest that hypopituitarism and microphthalmia may be associated with each other more frequently than has been recognized previously.     

Job interview training with rehabilitation clients: A comparison of videotape and role-playing procedures.

Randomly assigned 19 clients at a rehabilitation center to 1 of 3 treatments designed to improve job interview behavior. Judges' ratings indicated that Ss in a videotape-feedback condition and those in a role-playing condition improved significantly more than those in an attention-placebo control group, but that the 2 experimental groups did not differ from each other. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selection of pairwise multiple comparison procedures for parametric and nonparametric analysis of variance models.

Discusses 2 issues that are often overlooked in the evaluation of pairwise multiple comparison procedures (MCPs): Comparisons of powers for competing MCPs are not useful unless the procedures have identical nominal experimentwise error rates; and "protected" MCPs do not control the experimentwise Type I error rate at the nominal alpha except in the complete null case. Also, procedures based on the ranks of all K groups do not test the same hypothesis as MCPs that involve reranking the data for each pairwise comparison. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of inclusive and restrictive strategies in modern missing data procedures.

Two classes of modem missing data procedures, maximum likelihood (ML) and multiple imputation (MI), tend to yield similar results when implemented in comparable ways. In either approach, it is possible to include auxiliary variables solely for the purpose of improving the missing data procedure. A simulation was presented to assess the potential costs and benefits of a restrictive strategy, which makes minimal use of auxiliary variables, versus an inclusive strategy, which makes liberal use of such variables. The simulation showed that the inclusive strategy is to be greatly preferred. With an inclusive strategy not only is there a reduced chance of inadvertently omitting an important cause of missingness, there is also the possibility of noticeable gains in terms of increased efficiency and reduced bias, with only minor costs. As implemented in currently available software, the MI approach tends to encourage the use of a restrictive strategy, whereas the MI approach makes it relatively simple to use an inclusive strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Scanning electron microscopy of the bronchial mucosa in some lung diseases using bronchoscopy specimens. A pilot study including cases of bronchial carcinoma, sarcoidosis, silicosis and tuberculosis

In order to study the lung defence mechanisms and the mucociliary transport system scanning electron microscopy was performed on biopsy specimens obtained at bronchoscopy under local anaesthesia. There were great variations in the appearance of the cilitated epithelium from the large bronchi in 40 patients with bronchial carcinoma, sarcoidosis, silicosis, tuberculosis and other lung diseases. Areas with a low frequency of cilia were observed mainly in granulomatous disorders, and in silicosis, atypical cilia occurred abundantly. Squamous metaplasia with a complete loss of cilia was found in chronic bronchitis, bronchial carcinoma, after radiotherapy and in two of seven cases of sarcoidosis. Scanning electron microscopy seems to be an excellent method for studying the surface of the bronchial epithelium in many lung diseases, and may prove to be helpful in occupational medicine.     

Combination of behaviour therapy with fluvoxamine in comparison with behaviour therapy and placebo. Results of a multicentre study

BACKGROUND: We investigated whether the combination of multi-modal behaviour therapy (BT) with fluvoxamine is superior to BT and placebo in the acute treatment of severely ill in-patients with obsessive-compulsive disorder (OCD). METHOD: In a randomised, double-blind design, 30 patients were treated for nine weeks with BT plus placebo and 30 patients with BT plus fluvoxamine (maximum dosage 300 mg, mean dose 288.1 mg). BT included exposure with response prevention, cognitive restructuring and development of alternative behaviours. RESULTS: Both groups showed a highly significant symptom reduction after treatment. There were no significant differences between the groups concerning compulsions. Obsessions were significantly more reduced in the fluvoxamine and BT group than in the placebo and BT group. Furthermore, the group BT plus fluvoxamine showed a significantly higher response rate (87.5 v. 60%) according to a previously defined response criterion. Severely depressed patients with OCD receiving BT plus placebo presented a significantly worse treatment outcome (Y-BOCS scores) than all other groups. CONCLUSIONS: The results suggest that BT should be combined with fluvoxamine when obsessions dominate the clinical picture and when a secondary depression is present.