A SAS® macro implementation of a multiple comparison post hoc test for a Kruskal–Wallis analysis

2011 ◽  
Vol 102 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Alan C. Elliott ◽  
Linda S. Hynan
Keyword(s):  
Multiple Comparison ◽  
Post Hoc

Post Hoc Procedures for Some K-Sample Nonparametric Tests for Scale

1978 ◽  
Vol 3 (3) ◽  
pp. 265-282
Author(s):  
Douglas A. Penfield ◽  
Stephen L. Koffler
Keyword(s):  
Nonparametric Tests ◽  
Population Variability ◽  
Multiple Comparison ◽  
Chi Square ◽  
Bartlett Test ◽  
Nonparametric Alternatives ◽  
Post Hoc ◽  
Multiple Comparison Procedures

Post hoc multiple comparison procedures useful in assessing differences in population variability are formulated for three nonparametric alternatives to the parametric Bartlett test. The three nonparametric tests are the generalized Puri K-sample extensions of the Siegel-Tukey, Mood, and Klotz tests. Theory surrounding the development of these post hoc procedures is outlined and is based upon the chi-square analog to Scheffé’s theorem. An example illustrating an application of the methodology is presented.

Using Planned Comparisons in Management Research: A Case for the Bonferroni Procedure

1993 ◽  
Vol 19 (3) ◽  
pp. 707-724 ◽  
Author(s):  
Maria B. Castaiieda ◽  
Joel R. Levin ◽  
Randall B. Dunham
Keyword(s):  
Repeated Measures ◽  
Multivariate Analyses ◽  
A Priori ◽  
Comparison Method ◽  
Multiple Comparison ◽  
Management Research ◽  
Bonferroni Procedure ◽  
Sequential Hypothesis ◽  
Sequential Hypothesis Testing ◽  
Post Hoc

This article describes the Bonferroni multiple-comparison procedure, and makes a case for researchers’ more frequent and appropriate use of it. The procedure is discussed as a test that facilitates investigation of precise and powerful a priori multiple comparisons. Characteristics of the Bonferroni procedure are described in relation to the more familiar Scheffe post hoc multiple-comparison method, and a step-by-step guide for comparing and choosing between the two is provided. The Bonferroni procedure is discussed in detail in the context of one-factor analysis-of-variance designs. Application of the technique is then considered in the context of factorial designs, analyses of covariance, univariate repeated-measures analyses, multivariate analyses of variance, and recent sequential hypothesis-testing extensions. To aid the presentation, an example from the field of management is included.

scholarly journals Peningkatan Stabilitas Dimensi Hasil Cetakan Alginat Dengan Penambahan Pati Ubi Kayu dan Pati Sagu

2021 ◽  
Vol 2 (01) ◽  
pp. 1-7
Author(s):  
Syamsiah Syam ◽  
Risnayanti Anas ◽  
Muhammad Jayadi Abdi ◽  
Andi Tenri Biba ◽  
Chusnul Chotimah ◽  
...  
Keyword(s):  
Multiple Comparison ◽  
P Value ◽  
Cross Sectional ◽  
Post Hoc ◽  
One Way Anova

Pendahuluan: Alginat adalah bahan cetakan yang sering digunakan dalam kedokteran gigi. Bahan cetak alginat masih memiliki kelemahan dalam akurasi stabilitas dimensi, dimana alginat memiliki stabilitas dimensi yang cepat berubah. Tujuan Penelitian: Peneltian ini untuk mengetahui pengaruh penambahan pati ubi kayu dan pati sagu terhadap stabilitas dimensi hasil cetakan alginat. Bahan dan Metode: Penelitian ini menggunakan metode True Eksperimental Laboratorium dengan rancangan cross-sectional. Dimana jumlah sampel minimal diestimasikan berdasarkan rumus Federer. Penelitian ini dilakukan di laboratorium terpadu Fakultas Kedokteran Gigi Universitas Muslim Indonesia.  Hasil: Telah didapatkan berdasarkan uji one way anova diperoleh p-value sebesar 0,000 (p<0,05). Berdasarkan uji post hoc multiple comparison diperoleh perbedaan rata-rata antara pati ubi kayu ditambah alginat dengan kelompok kontrol sebesar 0,35500. Sedangkan untuk pati sagu ditambah alginat dengan kelompok kontrol sebesar 0,75500. Kesimpulan: Pada penelitian ini terdapat perubahan yang signifikan antara penambahan pati ubi kayu dan pati sagu terhadap stabilitas dimensi hasil cetakan alginat.

scholarly journals CYTOTOXIC LABDANE DITERPENOIDS FROM ANDROGRAPHIS PANICULATA (BURM.F.) NEES

2017 ◽  
Vol 10 (12) ◽  
pp. 99 ◽  
Author(s):  
Maria Carmens Tan ◽  
Glenn G Oyong ◽  
Chien Chang Shen ◽  
Consolacion Y Ragasa
Keyword(s):  
Dermal Fibroblasts ◽  
Multiple Comparison ◽  
Wild Type ◽  
Significant Difference ◽  
Hct 116 ◽  
Hct 116 Cells ◽  
Labdane Diterpenoids ◽  
Post Hoc ◽  
Ht 29 ◽  
Mcf 7

Objective: The primary objective of this study was to probe the cytotoxic capacity of the labdane diterpenoids andrographolide (1), 14-deoxyandrographolide (2), 14-deoxy-12-hydroxyandrographolide (3), and neoandrographolide (4) on mutant and wild-type immortalized cell lines.Methods: Breast adenocarcinoma (MCF-7), colon carcinomas (HCT-116 and HT-29), small cell lung carcinoma (H69PR), human acute monocytic leukemia (THP-1), and wild-type primary normal human dermal fibroblasts - neonatal cells (HDFn) were incubated with 1-4, and the degree of cytotoxicity was analyzed by employing the in vitro PrestoBlue® cell viability assay. Working solutions of 1-4 were prepared in complete cell culture medium to a final non-toxic dimethyl sulfoxide concentration of 0.2%. The plates were incubated at 37°C with 5% CO2 in a 98% humidified incubator throughout the assay. Nonlinear regression and statistical analyses were done to extrapolate the half maximal inhibitory concentration 50% (IC50). One-way ANOVA (p<0.05) and multiple comparison, Tukey’s post hoc test (p<0.05), were used to compare different pairs of data sets. Results were considered statistically significant at p<0.05.Results: The highest cytotoxicity index was exhibited by the H69PR and 1 trials which displayed the lowest IC50 value of 3.66 μg/mL, followed by HT-29 treated with 2, HCT-116 and 1 trials, and H69PR treated with 4 (IC50=3.81, 3.82, and 4.19 μg/mL, respectively). Only 1 and 4 were detrimental toward MCF-7, while 1, 3, and 4 were degenerative against H69PR. Tukey’s post hoc multiple comparison indicated no significant difference in the cytotoxicity of 1-4 on HCT-116 cells which afforded IC50 values ranging from 3.82 to 5.12 μg/mL. Evaluation of the two colon carcinoma cell lines showed that HCT-116 was categorically more susceptible to cellular damage caused by treatments with 1-4 than was HT-29. Cytotoxicity was not detected in THP-1 and HDFn cells (IC50>100 μg/mL).Conclusion: Diterpenoids 1-4 isolated from the dichloromethane extract of the leaves of A. paniculata exhibited different cytotoxic activities against MCF-7, HCT-116, HT-29, and H69PR. All constituents had comparable action on HCT-116 cells but were not found to be cytotoxic to normal HDFn cells and mutant THP-1 cells.

Scheffé’s More Powerful F-Protected Post Hoc Procedure

2000 ◽  
Vol 25 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Alan J. Klockars ◽  
Gregory R. Hancock
Keyword(s):  
Null Hypothesis ◽  
Degrees Of Freedom ◽  
Critical Value ◽  
Current Paper ◽  
Multiple Comparison ◽  
Simple Modification ◽  
Multiple Comparison Procedure ◽  
Post Hoc ◽  
Original Derivation

<italic>In 1970 Henry Scheffé proposed a more powerful version of his well known post hoc multiple comparison procedure, only to fail to recommend it by the paper's end. The point of the current paper is to bring this simple modification to a wider audience, complete with an original derivation, in hopes that the method will be embraced by researchers despite its creator's hesitations. Specifically, whereas Scheffé's original (1953) procedure advocates testing any exploratory post hoc contrast or comparison using a critical value assuming </italic>k - <italic>1 between-group degrees of freedom, Scheffé's later modification (1970) will be demonstrated here showing that a more liberal critical value assuming </italic>k - <italic>2 between-group degrees of freedom may be used if an omnibus null hypothesis across all means has been rejected. </italic>

scholarly journals The Effects of Mouthwashes on the Color Stability of Resin-Based Restorative Materials

2020 ◽  
pp. 346-357
Author(s):  
Ayşe Tuğba Ertürk-Avunduk ◽  
Seçkin Aksu ◽  
Ebru Delikan
Keyword(s):  
Analysis Of Variance ◽  
Color Change ◽  
Resin Composite ◽  
Color Stability ◽  
Multiple Comparison ◽  
Color Measurement ◽  
Distilled Water ◽  
Significant Difference ◽  
Restorative Materials ◽  
Post Hoc

Objective: This study investigated the effects of three types of mouthwash on the color stability of three resin-based restorative materials (nanohybrid resin composite, sonic-activated bulk-fill material, and compomer). Materials and Methods: To this end, 120 cylindrical disc specimens were prepared and polished, after which they were incubated in distilled water for 24 hours for post-polymerization. The baseline color values of each specimen were measured with a spectrophotometer, then the specimens were randomly divided into four groups. Following immersion in the mouthwashes for 24 hours, the specimens were rinsed with distilled water and dried before the color measurement was repeated. The values of color change (∆E₀₀) were subsequently calculated. A two-way analysis of variance and Duncan’s post hoc multiple comparison tests were conducted to determine statistically significant differences among the restorative materials. Results: All samples showed discoloration after immersion, albeit some instances of discoloration were imperceptible. In this respect, a statistically significant difference was found among the restorative materials and mouthwashes (p<0.05). Imperceptible ∆E₀₀ values were derived on the nanohybrid resin composite and compomer, but perceptible and acceptable ∆E₀₀ values were detected on the sonic-activated bulk-fill materials (p<0.05). The clinically unacceptable discoloration was observed on the sonic-activated bulk-fill composite immersed in Listerine®. Conclusions: Clinicians should make recommendations based on the potential staining capacity of mouthwashes prescribed for daily use in restorative materials. In this way, the need for renewal of restorations due to discoloration could be avoided.

scholarly journals Efektivitas Pemberian Ekstrak Buah Kersen (Muntingia Calabura) terhadap Rasio Berat Testis pada Tikus yang Dipapar Asap Rokok

2019 ◽  
Vol 1 (1) ◽  
pp. 15
Author(s):  
Ika Dyah Kurniati ◽  
Dyah Mustika Nugraheni
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen ◽  
Multiple Comparison ◽  
Oxygen Species ◽  
Sprague Dawley ◽  
Anova Test ◽  
Post Hoc ◽  
One Way Anova ◽  
Muntingia Calabura ◽  
Aromatic Hydrogen

Latar belakang : Reactive Oxygen Species (ROS) merupakan salah satu mediator terjadinya infertilitas. Produksi ROS akan meningkat dengan adanya polusi udara dan merokok. Polynuclear Aromatic Hydrogen (PAH) yang terkandung dalam asap rokok dapat menyebabkan atrofi testis, menghambat spermatogenesis, dan merusak morfologi spermatozoa. Apabila terjadi kerusakan atau atrofi sel-sel penyusun tubulus seminiferus akan terjadi penurunan berat testis. Buah kersen mengandung senyawa antioksidan yang dapat meningkatkan kualitas sperma. Tujuan penelitian ini adalah untuk mengetahui efek proteksi ekstrak buah kersen terhadap kerusakan testis tikus Sprague dawley yang terpapar asap rokok.Metode : Tikus sejumlah dibagi 4 kelompok, kemudian di papar asap rokok 7 batang perhari dan ekstrak buah kersen (EBK) selama 4 minggu. Kelompok pertama sebagai kontrol (K1) diberi plasebo, kelompok kedua (K2) dipapar asap rokok saja, sedangkan sisanya merupakan kelompok Perlakuan 1 (P1) diberi EBK 100mg/kgBB/hari dan Perlakuan 2 (P2) diberi EBK 200mg/kgBB/hari. Rasio berat testis di analisis dengan uji statistik parametrik One Way ANOVA Test dilanjutkan analisa Post Hoc Multiple Comparison Test.Hasil : Rasio berat testis pada kelompok kontrol (K1) sejumlah (0,31) kelompok perlakuan 1 (P1) sejumlah (0,24) dan kelompok perlakuan 2 (P2) sejumlah (0,28) sedangkan yang terendah yaitu pada kelompok kontrol paparan asap rokok (K2) sejumlah (0,19). Nilai P =  0,013, menunjukkan bahwa terdapat perbedaaan yang bermakna berat testis antar kelompok.Simpulan : Pemberian ekstrak buah kersen dapat meningkatkan rasio berat testis pada  tikus yang di papar asap rokok.

The Quest for α: Developments in Multiple Comparison Procedures in the Quarter Century Since

1996 ◽  
Vol 66 (3) ◽  
pp. 269-306 ◽  
Author(s):  
Gregory R. Hancock ◽  
Alan J. Klockars
Keyword(s):  
Type I Error ◽  
Reference Group ◽  
Error Rates ◽  
Multiple Comparison ◽  
Type I ◽  
Quarter Century ◽  
Homogeneity Of Variance ◽  
Current Article ◽  
Post Hoc ◽  
Multiple Comparison Procedures

In a highly regarded work, Games (1971) presented state-of-the-art multiple comparison procedures (MCPs) for a variety of research scenarios and sought to bring order to the seemingly chaotic array of MCPs being used at that time. The current article is a sequel of sorts, placing Games’s insights in the context of many of the major developments in simultaneous and sequential inference since his article’s publication. Specifically, we address the common MCP scenarios of orthogonal contrasts, nonorthogonal contrasts, comparisons against a reference group, all possible pairwise comparisons, and exploratory post hoc contrasts, all under the assumed conditions of independent scores, normality, and homogeneity of variance. In addition, discussions of the philosophical issues surrounding the control of Type I error rates are presented.

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