Analysis of Contingency Tables with Sparse Values

1979 ◽  
Vol 16 (3) ◽  
pp. 382-386 ◽  
Author(s):  
William S. Shields ◽  
Roger M. Heeler
Keyword(s):  
Contingency Tables ◽  
Fisher Exact Test ◽  
Financial Cost ◽  
Chi Square ◽  
Exact Test ◽  
Loss Of Information ◽  
Cell Counts ◽  
Chi Square Analysis ◽  
The Cost

In the chi square analysis of cross-tabulated variables, the problem of low cell counts is usually solved by combining categories, at the cost of a loss of information, or by using larger samples, at added financial cost. Use of a chi square statistic based on an extension of the Fisher Exact Test can provide a third, less costly, alternative.

scholarly journals Comparison of Transmissibility of Coronavirus Between Symptomatic and Asymptomatic Patients: Reanalysis of the Ningbo COVID-19 Data (Preprint)

2020 ◽  
Author(s):  
Guosheng Yin ◽  
Huaqing Jin
Keyword(s):  
Permutation Test ◽  
Fisher Exact Test ◽  
Chi Square ◽  
Exact Test ◽  
Transmission Rates ◽  
Cell Counts ◽  
Asymptomatic Patients ◽  
Original Analysis ◽  
Novel Coronavirus ◽  
The City

BACKGROUND Since the outbreak of the novel coronavirus disease (COVID-19) in December 2019, the coronavirus has spread all over the world at an unprecedented rate. The transmissibility of the coronavirus from asymptomatic patients to healthy individuals has received enormous attention. An important study using COVID-19 data from the city of Ningbo, China, was carried out to estimate and compare the transmission rates of the coronavirus by the symptomatic and asymptomatic patients. However, in the original analysis, the usual chi-square tests were unduly used for some contingency tables with small cell counts including zero, which may violate the assumptions for the chi-square test. OBJECTIVE We reanalyze the data from the city of Ningbo with more appropriate statistical methods to draw more reliable and sound conclusions on the transmission rates of the coronavirus by the symptomatic and asymptomatic patients. METHODS We excluded the cases associated with the super-spreader and adopted a more appropriate statistical method, including the permutation test and the Fisher exact test, to reanalyze the COVID-19 data from the city of Ningbo. RESULTS After excluding the cases related to the super-spreader, the Fisher exact test yields a <i>P</i> value of .84, which indicates stronger evidence of no difference in the transmission rates compared with the original analysis. The odds ratio of the coronavirus transmission rates between the symptomatic and asymptomatic patients is 1.2 with a 95% confidence interval 0.5-2.8. CONCLUSIONS Through a more in-depth and comprehensive statistical analysis of the Ningbo data, we concluded that there is no difference in the transmission rates of coronavirus between symptomatic and asymptomatic patients.

IIB or not IIB, part 1: retrospective evaluation of Kenney–Doig categorization of equine endometrial biopsies at a veterinary diagnostic laboratory and comparison with published reports

2021 ◽  
pp. 104063872110622
Author(s):  
Jane Westendorf ◽  
Bruce Wobeser ◽  
Tasha Epp
Keyword(s):  
Observer Variation ◽  
Fisher Exact Test ◽  
Observer Variability ◽  
Retrospective Evaluation ◽  
Review Of The Literature ◽  
Rater Agreement ◽  
Chi Square ◽  
Diagnostic Laboratory ◽  
Exact Test ◽  
Chi Square Analysis

The Kenney–Doig scale is a histopathology categorization (grading) system often used as the standard for assessing endometrial disease and communicating prognostic fertility information for equine breeding prospects. We investigated how Kenney–Doig categories compared within the same institution and across different institutions to determine if observer variability may contribute to category frequencies. We conducted a retrospective analysis of all equine endometrial submission records between 1998 and 2018 at the Western College of Veterinary Medicine (WCVM) and Prairie Diagnostic Services (PDS). Of 726 biopsies, we found the following category distribution: 46 of 726 (6.3%) I, 307 of 726 (42.3%) IIA, 326 of 726 (44.9%) IIB, and 47 of 726 (6.5%) III. We also conducted a review of the literature and included 6 studies reporting Kenney–Doig category distributions. Chi-square analysis showed significant differences between the category distribution found at WCVM and PDS and the category distribution reported in the 6 studies. To account for differences in mare populations, individual category distributions were generated for 5 pathologists at the WCVM and PDS. The Fisher exact test among these 5 Kenney–Doig categories revealed significant differences in category tendencies, suggesting that observer variation affects the use of the scale. Our results suggest that there is a need for prospective inter-rater and intra-rater agreement studies of the repeatability of the Kenney–Doig scale.

scholarly journals Comparison of Transmissibility of Coronavirus Between Symptomatic and Asymptomatic Patients: Reanalysis of the Ningbo COVID-19 Data

10.2196/19464 ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. e19464 ◽  
Author(s):  
Guosheng Yin ◽  
Huaqing Jin
Keyword(s):  
Permutation Test ◽  
P Value ◽  
Fisher Exact Test ◽  
Chi Square ◽  
Exact Test ◽  
Transmission Rates ◽  
Cell Counts ◽  
Asymptomatic Patients ◽  
Original Analysis ◽  
The City

Background Since the outbreak of the novel coronavirus disease (COVID-19) in December 2019, the coronavirus has spread all over the world at an unprecedented rate. The transmissibility of the coronavirus from asymptomatic patients to healthy individuals has received enormous attention. An important study using COVID-19 data from the city of Ningbo, China, was carried out to estimate and compare the transmission rates of the coronavirus by the symptomatic and asymptomatic patients. However, in the original analysis, the usual chi-square tests were unduly used for some contingency tables with small cell counts including zero, which may violate the assumptions for the chi-square test. Objective We reanalyze the data from the city of Ningbo with more appropriate statistical methods to draw more reliable and sound conclusions on the transmission rates of the coronavirus by the symptomatic and asymptomatic patients. Methods We excluded the cases associated with the super-spreader and adopted a more appropriate statistical method, including the permutation test and the Fisher exact test, to reanalyze the COVID-19 data from the city of Ningbo. Results After excluding the cases related to the super-spreader, the Fisher exact test yields a P value of .84, which indicates stronger evidence of no difference in the transmission rates compared with the original analysis. The odds ratio of the coronavirus transmission rates between the symptomatic and asymptomatic patients is 1.2 with a 95% confidence interval 0.5-2.8. Conclusions Through a more in-depth and comprehensive statistical analysis of the Ningbo data, we concluded that there is no difference in the transmission rates of coronavirus between symptomatic and asymptomatic patients.

scholarly journals Exploring Flood-Related Unintentional Fatal Drowning of Children and Adolescents Aged 0–19 Years in Australia

Safety ◽  
2019 ◽  
Vol 5 (3) ◽  
pp. 46 ◽  
Author(s):  
Amy E. Peden ◽  
Richard C. Franklin
Keyword(s):  
Children And Adolescents ◽  
Total Population ◽  
Chi Square ◽  
Exact Test ◽  
Remote Areas ◽  
Socially Disadvantaged ◽  
Cell Counts ◽  
Adult Supervision ◽  
Chi Square Analysis ◽  
Almost All

Disasters, such as flooding, are predicted to increase. Drowning is one of the leading causes of death during times of flood. This study examined the little explored topic of child drowning during floods, with the aim of identifying risk factors to inform prevention strategies. A retrospective, total population examination of cases of children and adolescents aged 0–19 years who died from unintentional flood-related drowning in Australia for the 16-year period 1 July 2002 to 30 June 2018 was undertaken. Univariate and chi-square analysis was conducted, with Fisher’s exact test used for cell counts <5. Across the study period, 44 flood-related drowning deaths occurred among children and adolescents (63.6% male; 34.1% aged 10–14 years). Almost all (84.1%) occurred in rivers, creeks, or streams in flood, with the remaining incidents occurring in storm water drains (n = 7). Leading activities immediately prior to drowning were non-aquatic transport (40.9%), swimming in floodwaters (25.0%), and falls into floodwaters (15.9%). Flood-related fatal drowning among children and adolescents is rare (0.05 per 100,000 population), however flood-drowning risk increases as remoteness increases, with children and adolescents drowning in floodwaters in very remote areas at a rate 57 times that of major cities. All drownings are preventable, and this study has identified key causal factors that must be considered in advocacy and prevention efforts. These include: the importance of adult supervision, avoiding flooded waterways when driving or for recreational purposes, and the increased risks for those residing in geographically isolated and socially disadvantaged areas. Findings must be considered when developing interventions and advocacy for the purposes of the reduction of child and adolescent drowning during times of flood.

Venous Thromboembolism and High Grade Gliomas

1993 ◽  
Vol 70 (03) ◽  
pp. 393-396 ◽  
Author(s):  
Mandeep S Dhami ◽  
Robert D Bona ◽  
John A Calogero ◽  
Richard M Hellman
Keyword(s):  
Risk Factors ◽  
Venous Thromboembolism ◽  
Medical Center ◽  
Significant Risk ◽  
Bleeding Complications ◽  
Fisher Exact Test ◽  
High Grade ◽  
Chi Square ◽  
Exact Test ◽  
High Grade Gliomas

SummaryA retrospective study was done to determine the incidence of and the risk factors predisposing to clinical venous thromboembolism (VTE) in patients treated for high grade gliomas. Medical records of 68 consecutive patients diagnosed and treated at Saint Francis Hospital and Medical Center from January 1986 to June 1991 were reviewed. The follow up was to time of death or at least 6 months (up to December 1991). All clinically suspected episodes of VTE were confirmed by objective tests. Sixteen episodes of VTE were detected in 13 patients for an overall episode rate of 23.5%. Administration of chemotherapy (p = 0.027, two tailed Fisher exact test) and presence of paresis (p = 0.031, two tailed Fisher exact test) were statistically significant risk factors for the development of VTE. Thrombotic events were more likely to occur in the paretic limb and this difference was statistically significant (p = 0.00049, chi square test, with Yates correction). No major bleeding complications were seen in the nine episodes treated with long term anticoagulation.We conclude that venous thromboembolic complications are frequently encountered in patients being treated for high grade gliomas and the presence of paresis and the administration of chemotherapy increases the risk of such complications.

A year of hepatocellular carcinoma at a glance. Demographics, biochemical and radiological characteristics and treatment modalities from a specialized facility of Pakistan

2021 ◽  
pp. 1-6
Author(s):  
Laima Alam
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cross Sectional Study ◽  
Treatment Modalities ◽  
Fisher Exact Test ◽  
Tumour Staging ◽  
Chi Square ◽  
Cross Sectional ◽  
Exact Test ◽  
Team Meetings ◽  
Contrast Enhanced Ct

Objectives:Relation of demographics of hepatocellular-carcinoma with the aetiology.Tumour characteristics in relation to anti-viral therapy and presence of viral-DNA/RNATreatment modalities offeredMethods: This cross-sectional study enrolled all the patients aged 18-70 years with diagnosed hepatocellular carcinoma either through Triphasic Contrast-Enhanced-CT scan and/or Magnetic Resonance Imaging or biopsy presenting to the Outpatient-Department or multi-disciplinary-team meetings for the year 2019. Demographic variables, biochemical analysis including liver profile and stage of cirrhosis, viral-status, tumour staging and the treatment modalities offered were all noted. ANOVA (normal) and Kruskal-Wallis (non-normal) tests were used to compare quantitative data whereas chi-square-test and fisher-exact-test were used to compare qualitative-data.Results: Out of 195 patients with hepatocellular carcinoma, 76% were males in their fifth to sixth decades of life, 96% had cirrhosis, 94% corresponded to viral hepatocellular-carcinoma (82% Hepatitis-C-Virus, 9% Hepatitis-B-Virus and 3% coinfection), 60% of the cirrhotics landed in Child-Pugh A category with tumour staging BCLC-B being the predominant one (43.6%) and single and multiple bilateral nodules were the commonest lesions encountered. Platelets and Alanine-Transaminase had a significant relation across aetiological groups. Lymph-nodes were the most common extra-hepatic organs for metastasis and the presence of viral PCR had a significant impact on the tumour aggressiveness. Thirty-two percent of the patients were amenable to curative treatment.Conclusion: Viral infection is the main cause of rising prevalence of this tumour in Pakistan. Treatment modalities are expensive and expertise are lacking. A nationwide cancer registry is required for the exact disease burden and tumour behaviour for our population. Continuous....

scholarly journals Phlebitis associated with peripheral intravenous catheters in adults admitted to hospital in the Western Brazilian Amazon

2016 ◽  
Vol 50 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Sandra Maria Sampaio Enes ◽  
Simone Perufo Opitz ◽  
André Ricardo Maia da Costa de Faro ◽  
Mavilde de Luz Gonçalves Pedreira
Keyword(s):  
Intermittent Infusion ◽  
Brazilian Amazon ◽  
Fisher Exact Test ◽  
Intravenous Therapy ◽  
Chi Square ◽  
Significance Level ◽  
Exact Test ◽  
Dorsal Hand Vein ◽  
Mean Time ◽  
Intravenous Catheters

Abstract OBJECTIVE To identify the presence of phlebitis and the factors that influence the development of this complication in adult patients admitted to hospital in the western Brazilian Amazon. METHOD Exploratory study with a sample of 122 peripheral intravenous catheters inserted in 122 patients in a medical unit. Variables related to the patient and intravenous therapy were analyzed. For the analysis, we used chi-square tests of Pearson and Fisher exact test, with 5% significance level. RESULTS Complication was the main reason for catheter removal (67.2%), phlebitis was the most frequent complication (31.1%). The mean duration of intravenous therapy use was 8.81 days in continuous and intermittent infusion (61.5%), in 20G catheter (39.3%), inserted in the dorsal hand vein arc (36.9 %), with mean time of usage of 68.4 hours. The type of infusion (p=0.044) and the presence of chronic disease (p=0.005) and infection (p=0.007) affected the development of phlebitis. CONCLUSION There was a high frequency of phlebitis in the sample, being influenced by concomitant use of continuous and intermittent infusion of drugs and solutions, and more frequent in patients with chronic diseases and infection.

scholarly journals FAKTOR-FAKTOR YANG MEMENGARUHI NEUROPATI PERIFER TERKAIT HIV DI MANADO

2018 ◽  
Vol 35 (3) ◽  
Author(s):  
Deivy Cirayow ◽  
Arthur Hendrik Philips Mawuntu ◽  
Herlyani Khosama
Keyword(s):  
Neuropathic Pain ◽  
Peripheral Neuropathy ◽  
Influencing Factors ◽  
Categorical Variables ◽  
Fisher Exact Test ◽  
Hiv Dementia ◽  
Chi Square ◽  
Exact Test ◽  
International Hiv Dementia Scale ◽  
Hiv Aids

FACTORS THAT INFLUENCE HIV ASSOCIATED PERIPHERAL NEUROPATHY IN MANADOABSTRACTIntroduction: There are  several sociodemographic and clinical factors that influence the development of HIV associated peripheral  neuropathy (HIV-PN). Manado has different sociodemographic and clinical characteristics  from other regions. However, the percentage of HIV-PN and its influencing factors are unknown.Aims: To know the percentage of HIV-PN and factors that influence this disorder in Manado.Methods: A crosssectional study conducted in HIV/AIDS clinic R.D. Kandou hospital Manado between November2016–January 2017. Neuropathy evaluation was performed using brief peripheral neuropathy screening (BPNS), neuropathic pain diagnostic questionnaire (DN4), and electroneurography. A Chi-square or Fisher exact test was done to analyze categorical variables, independent T or Mann-Whitney test was done for numerical variables, and linear regression was done in multivariate analysis.Results: 50 subjects were included, most were male (70%), and the mean age was 32.98 (±9.726) years, with HIV- NP percentage was 46%. Age >30 years old, low hemoglobin count, CD4, and low international  HIV dementia scale (IHDS) significantly associated with HIV-NP. Working subjects were 13.6 times more likely to have HIV-PN.Discussion: HIV-PN prevalence was relatively high, influenced by age >30 years old an low hemoglobin, CD4, andIHDS. As a factor, working was escalating the likelihood of NP-HIV by 13.9 times.Keywords: HIV/AIDS, influencing factors, peripheral neuropathyABSTRAKPendahuluan: Neuropati perifer terkait human immunodeficiency virus/HIV (NP-HIV) dapat dipengaruhi oleh beberapa faktor klinis dan sosiodemografis. Manado mempunyai karakteristik yang berbeda dengan daerah lain, namun belum diketahui persentase NP-HIV dan faktor-faktor yang memengaruhinya.Tujuan: Mengetahui persentase NP-HIV dan faktor-faktor yang memengaruhinya di Manado.Metode: Penelitian potong lintang terhadap pasien HIV/AIDS di poliklinik HIV/AIDS RSUP Prof. dr. R.D. Kandou, Manado, pada November 2016–Januari 2017.  Evaluasi neuropati dilakukan menggunakan brief peripheral  neuropathy screening (BPNS), neuropathic pain diagnostic questionnaire (DN4), dan elektroneurografi. Digunakan uji Chi-square atau Fisher exact untuk menganalisis variabel kategorik, uji T independen atau Mann-Whitney untuk variabel numerik, dan regresi linear untuk analisis multivariat.Hasil: Didapatkan 50 subjek yang memenuhi kriteria penelitian dengan mayoritas laki-laki (70%), rerata usia32,98±9,726 tahun, dan mengalami NP-HIV sebanyak 46%. Usia >30 tahun, kadar hemoglobin, jumlah CD4, dan skor international  HIV dementia scale (IHDS) yang rendah berhubungan secara bermakna dengan adanya NP-HIV. Adapun subjek yang bekerja berisiko 13,6 kali lebih besar mengalami NP-HIV.Diskusi: Didapatkan prevalensi NP-HIV yang cukup tinggi dengan dipengaruhi oleh usia >30 tahun serta kadar hemoglobin, CD4, dan skor IHDS yang rendah. Faktor bekerja juga meningkatkan kecenderungan 13,9 kali mengalami NP terkait HIV.Kata kunci: Faktor-faktor yang memengaruhi, HIV/AIDS, neuropati perifer

scholarly journals Status Pekerjaan Dan Pengetahuan Ibu Menyusui Terhadap Pemberian ASI Eksklusif

2018 ◽  
Vol 16 (2) ◽  
pp. 236-244
Author(s):  
Happy Marthalena Simanungkalit
Keyword(s):  
Fisher Exact Test ◽  
Chi Square ◽  
Cross Sectional ◽  
Exact Test

Latar Belakang : Air Susu Ibu (ASI) selain merupakan makanan paling baik untuk bayi, juga terbukti dapat mencegah penyakit pada bayi dan memberi manfaat bagi ibu, keluarga, dan masyarakat. Memberikan ASI selama 6 bulan dapat menyelamatkan 1,3 juta jiwa di seluruh dunia. Tahun 2016 capaian pemberian ASI eksklusif di Wilayah Kerja Puskesmas Jekan Raya masih rendah. Tujuan Penelitian: Penelitian ini merupakan crosssectional study yang bersifat analitik Populasinya adalah seluruh ibu yang memiliki anak usia 6-12 bulan. Metode Penelitian: Penelitian ini menggunakan penelitian observasional analitik dengan metode Cross Sectional. Jumlah sampel yaitu sebanyak 79 responden. Adapun cara pengumpulan data dengan wawancara. Uji statistik yang digunakan adalah uji Chi-square (X2) dan Fisher Exact Test. Hasil penelitian: Variabel yang memiliki hubungan dengan pemberian ASI eksklusif yaitu pengetahuan (p=0,000). Sedangkan untuk variabel lainnya, yaitu umur (Fisher Exact Test = 0,120), pendidikan (p = 0,075) dan pekerjaan (p = 0,976) tidak menunjukkan adanya hubungan dengan pemberian ASI eksklusif. Kesimpulan: Variabel pengetahuan menunjukkan hubungan yang bermakna dengan pemberian ASI eksklusif. Variabel umur, pendidikan dan pekerjaan menunjukkan hubungan yang tidak bermakna dengan pemberian ASI eksklusif.

scholarly journals Evaluation of toxoplasmosis risk on anxiety and perception of cat owner pregnant women

2021 ◽  
Vol 38 (2) ◽  
pp. 154-158
Author(s):  
Nur DOKUZEYLUL GÜNGÖR ◽  
Tuğba GÜRBÜZ ◽  
Selma Bozkurt ZİNCİR ◽  
Banu DOKUZEYLÜL ◽  
Erman OR ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Pregnant Women ◽  
Health Anxiety ◽  
Anxiety Level ◽  
Fisher Exact Test ◽  
Chi Square ◽  
Exact Test ◽  
Main Host ◽  
The Difference ◽  
At Home

Cats are the main host of Toxoplasma gondii and pregnant women who own cats at home may be at risk. This condition may cause anxiety and stress in pregnant women. The aim of this study is to evaluate toxoplasmosis risk on anxiety and perception of cat owner pregnant women. The study group consisted of 59 pregnant women feeding cats in the home and 369 pregnant women not feeding cats. A Health Anxiety Inventory (HAI-18) was used to measure the anxiety of all participants. Age and anxiety variables were analyzed using a two-sample independent t-test. Gravida, education, and job status were analyzed using chi-square tests, and live to abort ratio & pregnancy number were analyzed using Fisher exact test. Measurement of the anxiety level between the two groups showed that anxiety is significantly higher among the pregnant women who feed cats in their house with an average of 32.03±8.72. The average anxiety level among the pregnant women who don't have cats in their house was 25.94±8.99. The difference between the Health Anxiety Inventory of the two groups was significant (p= 0.0001) It was shown in the literature that pets can reduce anxiety but not studied in pregnant women, yet. Our results showed that pregnant women who own cats at home had more environmental anxiety than women who don’t feed cats at home which is possibly associated with fear of Toxoplasma gondii transmission. This anxiety may also cause unfavorable pregnancy outcomes like eclampsia, preterm birth, low birth weight and high incidence of cesarean delivery.

Sign in / Sign up

Export Citation Format

Share Document