975 resultados para Chi-square test
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Student retention is a primary goal in all higher education institutions. Students who are more adjusted to college life are more likely to persist. The purpose of this research was to determine the effects of an outdoor experiential team-building program on the college adjustment of first-semester freshmen in learning communities at a diverse, urban university. The participants in this quasi-experimental study were first-semester freshmen enrolled in learning communities. A total of 123 students participated, with 61 students in the experimental group and 62 students in the comparison group. There were no significant differences between the two groups in relation to age, gender, or ethnicity. The students in the experimental group participated in the team-building program, which consisted of three events spaced three and four weeks apart. At the end of the semester, students in both the experimental and comparison groups completed the Student Adaptation to College Questionnaire (SACQ), a 67-item self-report survey. ^ Independent samples t-test of the SACQ scores (for attachment to the institution, social adjustment, and overall adaptation to college) between groups was done, and the analyses revealed no statistically significant differences. Chi-square analyses revealed no significant difference in the enrollment pattern between the two groups over a four-year period. Repeated measures ANOVAs revealed that from the first semester of enrollment to the second semester there was a significant drop in GPA for students from the comparison group and no such drop in GPA for students from the experimental group who had participated in at least two of the team building activities. A repeated measures ANOVA was conducted for the first year by semester and ethnicity. No ethnic differences were found, and no interaction was found by ethnicity and semester. ^ Should colleges and universities continue to utilize outdoor experiential team-building programs as a creative way to influence students' connection to the institution they should further investigate its value on students' adjustment to college. Future studies should also consider other variables influenced by team-building programs that affect students' college adjustment, such as collaborative learning. Faculty should be included in the planning process to increase their participation. ^
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The purpose of this study was to examine the hypothesis that no differences existed in the upper division performance of academically excellent community college transfer students when compared to native university students. The relationship of enrollment patterns such as skipped terms, dropped terms, summer session utilization, college of major, credits attempted, credits received, test scores, and current status were also studied.^ The data were collected through a hand analysis of 673 student transcripts which provided the information for a database designed specifically for this study. The subjects were 229 transfers from Miami-Dade Community College and 444 natives from Florida International University. The students all began their studies in the lower division in the Fall term of 1982, 1983 or 1984 and eventually transferred to the upper division at FIU. This longitudinal study followed the upper division performance and enrollment patterns through the Spring term of 1991.^ Data analysis included chi-square for all categorical and numerical variables; t-tests were performed for the numerical variables. Correlation coefficients, Two-Way Analysis of Variance and Three-Way Crosstabulations were also used when indicated. There were significant differences among the upper division performance of community college transfer students and native university students for the graduation rate and the GPA range. A significant difference was also found between the math and essay CLAST scores, number of summer terms utilized, number of terms to graduation, current enrollment status, and credits attempted and received for the groups. ^
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Prior to 2000, there were less than 1.6 million students enrolled in at least one online course. By fall 2010, student enrollment in online distance education showed a phenomenal 283% increase to 6.1 million. Two years later, this number had grown to 7.1 million. In light of this significant growth and skepticism about quality, there have been calls for greater oversight of this format of educational delivery. Accrediting bodies tasked with this oversight have developed guidelines and standards for online education. There is a lack of empirical studies that examine the relationship between accrediting standards and student success. The purpose of this study was to examine the relationship between the presence of Southern Association of Colleges and Schools Commission on College (SACSCOC) standards for online education in online courses, (a) student support services and (b) curriculum and instruction, and student success. An original 24-item survey with an overall reliability coefficient of .94 was administered to students (N=464) at Florida International University, enrolled in 24 university-wide undergraduate online courses during fall 2014, who rated the presence of these standards in their online courses. The general linear model was utilized to analyze the data. The results of the study indicated that the two standards, student support services and curriculum and instruction were both significantly and positively correlated with student success but with small R2 and strengths of association less than .35 and .20 respectively. Mixed results were produced from Chi-square tests for differences in student success between higher and lower rated online courses when controlling for various covariates such as discipline, gender, race/ethnicity, GPA, age, and number of online courses previously taken. A multiple linear regression analysis revealed that the curriculum and instruction standard was the only variable that accounted for a significant amount of unique variance in student success. Another regression test revealed that no significant interaction effect exists between the two SACSCOC standards and GPA in predicting student success. The results of this study are useful for administrators, faculty, and researchers who are interested in accreditation standards for online education and how these standards relate to student success.
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The purpose of this dissertation was to examine the effect of academic integration, defined in terms of instructor/student contact, on the persistence of under-prepared college students and the achievement of those who persist. The overall design of this study compared instructor-initiated contact with conventional contact. The dependent variables were persistence, achievement, motivation and anxiety. Information was collected by administering the College-Level Mathematics Test (CLM), the Perceived Affective Contact Questionnaire (PAC), the expectancy and anxiety components of the Motivated Strategies for Learning Questionnaire (MSLQ), a departmental final examination, and by accessing university records. The sample consisted of 130 college algebra students at a large, public university with a Hispanic majority. The main analyses consisted of a 2x2x2 ANOVA (treatment by ethnicity by gender) to test for differences in achievement, t-tests to compare motivation, anxiety and perceived affective contact scores for the two groups, Chi-square tests to assess differences in persistence, and Pearson Product-Moment Correlation to determine the relationship between pretest scores and achievement variables. Results indicated that neither instructor-initiated contact, gender nor ethnicity is related to persistence, motivation or anxiety. A significant disordinal interaction of treatment and ethnicity was observed, with Hispanic experimental students scoring significantly higher on a test of algebra achievement than Hispanic control students. Academic integration, defined in terms of instructor/student contact, has a positive influence on the achievement of Hispanic students. This may imply their positive responsiveness to the relational aspect of contact due to traditional cultural values of interdependence, acquiescence to authority and physical closeness. Such interactive feedback is a means by which students with these values are recognized as members of the university academic community, prompting increased academic effort. Training in contact initiation to promote academic integration is implied, by the results of this study, for instructors dealing with first year students, especially instructors at institutions accommodating instructional methods to the needs of diverse groups.
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The purpose of this study was to investigate the effect of multimedia instruction on achievement of college students in AMH 2010 from exploration and discovery to1865. A non-equivalent control group design was used. The dependent variable was achievement. The independent variables were learning styles method of instruction, and visual clarifiers (notes). The study was conducted using two history sections from Palm Beach Community College, in Boca Raton, Florida, between August and December, 1998. Data were obtained by means of placement scores, posttests, the Productivity Environmental Preference Survey (PEPS), and a researcher-developed student survey. Statistical analysis of the data was done using SPSS statistical software. Demographic variables were compared using Chi square. T tests were run on the posttests to determine the equality of variances. The posttest scores of the groups were compared using the analysis of covariance (ANCOVA) at the .05 level of significance. The first hypothesis there is a significant difference in students' learning of U.S. History when students receive multimedia instruction was supported, F = (1, 52)= 688, p < .0005, and F = (1, 53) = 8.52, p < .005for Tests 2 and 3, respectively. The second hypothesis there is a significant difference on the effectiveness of multimedia instruction based on students' various learning preferences was not supported. The last hypotheses there is a significant difference on students' learning of U.S. History when students whose first language is other than English and students who need remediation receive visual clarifiers were not supported. Analysis of covariance (ANCOVA) indicated no difference between the groups on Test 1, Test 2, or Test 3: F (1, 4 5)= .01, p < .940, F (l, 52) = .77, p < .385, and F (1,53) =.17, p > .678, respectively, for language. Analysis of covariance (ANCOVA) indicated no significant difference on Test 1, Test 2, or Test 3, between the groups on the variable remediation: F (1, 45) = .31, p < .580, F (1, 52) = 1.44, p < .236, and F (1, 53) = .21, p < .645, respectively.
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This work has the main objective to obtain nano and microcrystals of cellulose, extracted from the pineapple leaf fibres (PALF), as reinforcement for the manufacture of biocomposite films with polymeric matrices of Poly(vinyl alcohol) (PVA) and Poly(lactic acid) (PLA). The polymer matrices and the nano and microcrystals of cellulose were characterised by means of TGA, FTIR and DSC. The analysis was performed on the pineapple leaves to identify the macro and micronutrients. The fibers of the leaves of the pineapple were extracted in a desfibradeira mechanical. The PALF extracted were washed to remove washable impurities and subsequently treated with sodium hydroxide (NaOH) and sodium hypochlorite (NaClO) in the removal of impurities, such as fat, grease, pectates, pectin and lignin. The processed PALF fibers were hydrolysed in sulfuric acid (H2SO4) at a concentration of 13.5 %, to obtain nano and microcrystals of cellulose. In the manufacture of biocomposite films, concentrations of cellulose, 0 %, 1 %, 3 %, 6 %, 9% and 12% were used as reinforcement to the matrices of PVA and PLA. The PVA was dissolved in distilled water at 80 ± 5 oC and the PLA was dissolved in dichloromethane at room temperature. The manufacture of biocompósitos in the form of films was carried out by "casting". Tests were carried out to study the water absorption by the films and mechanical test of resistance to traction according to ASTM D638-10 with a velocity of 50 mm/min.. Chi-square statistical test was used to check for the existence of significant differences in the level of 0.05: the lengths of the PALF, lengths of the nano and microcrystals of cellulose and the procedures used for the filtration using filter syringe of 0.2 μm or filtration and centrifugation. The hydrophilicity of biocompósitos was analysed by measuring the contact angle and the thickness of biocompósitos were compared as well as the results of tests of traction. Statistical T test - Student was also applied with the significance level (0.05). In biodegradation, Sturm test of standard D5209 was used. Nano and microcrystals of cellulose with lengths ranging from 7.33 nm to 186.17 nm were found. The PVA films showed average thicknesses of 0.153 μm and PLA 0.210 μm. There is a strong linear correlation directly proportional between the traction of the films of PVA and the concentration of cellulose in the films (composite) (0,7336), while the thickness of the film was correlated in 0.1404. Nano and microcrystals of cellulose and thickness together, correlated to 0.8740. While the correlation between the cellulose content and tensile strength was weak and inversely proportional (- 0,0057) and thickness in -0.2602, totaling -0,2659 in PLA films. This can be attributed to the nano and microcrystals of cellulose not fully adsorbed to the PLA matrix. In the comparison of the results of the traction of the two polymer matrices, the nano and microcrystals have helped in reducing the traction of the films (composite) of PLA. There was still the degradation of the film of PVA, within a period of 20 days, which was not seen in the PLA film, on the other hand, the observations made in the literature, the average time to start the degradation is above 60 days. What can be said that the films are biodegradable composites, with hydrophilicity and the nano and microcrystals of cellulose, contribute positively in the improvement of the results of polymer matrices used.
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The practices developed in the everyday life of obstetric services are sometimes out of step with the recommendations of the public health policies. Accordingly, this research had the objective of assessing the quality of the care provided to women and children during cases of natural childbirth in municipal public maternity wards of the city of Natal/RN, Brazilian Northeast. We developed a cross-sectional and quantitative study in two maternity wards that provide care actions to pregnant women at regular risk (maternity wards A and B). The participants were 314 puerperal women who were treated during the period between April and July 2014, whose children were born alive, through transpelvic way, with spontaneous or induced beginning of labor and that showed physical and emotional conditions to respond to the proposed questions. The data collection instrument was constructed on the basis of the recommendations of the World Health Organization focused on the care of normal childbirth and validated by skilled judges, and the final version has obtained optimum agreement (k = 0,96; IVC = 0,99). Associated with these recommendations, we used three indicators: percentage of women with induced labor or subjected to elective cesarean section (Indicator A); percentage of women served by a qualified health professional during labor and childbirth (Indicator B); and Bologna Index (Indicator C). The research obtained a favorable opinion of the Research Ethics Committee from the Federal University of Rio Grande do Norte, under the nº 562.313 and Certificate of Presentation for Ethics Appreciation: 25958513.0.0000.5537. The analysis of categories related to the recommendations of the World Health Organization was conducted by means of absolute and relative frequency and the Chi-square Pearson’s and Fisher’s exact tests made the comparison of the differences observed between the two maternity wards. Furthermore, we calculated the percentage of the indicators A and B and with the results of the Indicator C, the quality was assessed as follows: the closer to 5, the better will be the quality, and the closer to 0, the worst will be the quality, and the Mann-Whitney U test was used to compare the differences of the obtained averages. The significance level of 5% was considered in all statistical tests. The differences between the maternity wards were identified with regard to the provision of liquids orally (p=0,018), stimulus for non-supine positions (p=0,002), existence of partograph (p=0,001), support or welcoming by health professionals (p= 0,047), intravenous infusion (p<0,001), supine position (p<0,001), use of oxytocin (p<0,001), food and liquid restriction (p= 0,002) and, lastly, the fact of the touch is performed by more than 1 examiner (p=0,011). The indicators A and B showed percentages of 13,09% and 100%, respectively. The overall average of the Indicator C was equal to 2,07 (± 0,74). There was a statistically significant difference between the averages of the maternity wards (p<0,001). The care actions provided during the process of labor and childbirth is inappropriate, especially in the maternity ward B. It is necessary to implement improvements and redesign the obstetric model in force
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Introduction: Polycystic ovary syndrome (PCOS) whose classic features (menstrual irregularity of oligo/ amenorrhea type, chronic anovulation, infertility and hyperandrogenism clinical and/ or biochemical), is associated with aspects of metabolic syndrome (MS), as obesity and insulin resistance. The level of obesity determines different levels of inflammation, increasing cytokines participants of metabolic and endocrine functions, beyond modulate the immune response. Metabolic changes, added to the imbalance of sex hormones underlying irregular menstruation observed in (PCOS) can trigger allergic processes and elevation of total and specific IgE antibodies indicate that a sensitization process was started. Objective: To evaluate the influence of PCOS on biochemical parameters and levels of total and specific IgE to aeroallergens in obese women. Methods: After approval by the Committee of Ethics in Research, were recruited 80 volunteers with BMI ≥ 30 kg/m2 and age between 18 and 45 years. Among these, 40 with PCOS according to the Rotterdam criteria and 40 women without PCOS (control group). All participants were analysed with regard to anthropometric, clinical, gynecological parameters, interviewed using a questionnaire, and underwent blood sampling for realization of laboratory tests of clinical biochemistry: Total cholesterol, LDL-cholesterol, HDL- cholesterol, Triglycerides, Fasting glucose, Urea, Creatinine, Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and immunological: total and specific IgE to Dermatophagoides pteronyssinus, Blomia tropicalis, Dermatophagoides farinae and Dermatophagoides microceras.Statistical analysis was performed using SPSS 15.0 software through the chi-square tests, Fisher, Student t test and binary logistic regression, with significance level (p <0.05). Results: It was observed in the group of obese women with PCOS that 29 (72.5%) had menstrual cycle variable and 27 (67.5%) had difficulty getting pregnant. According to waist-hip ratio, higher average was also observed in obese PCOS (0.87). Blood level of HDL (36.9 mg/dL) and ALT (29.3 U/L) were above normal levels in obese women with PCOS, with statistically significant relationship. In the analysis of total and specific IgE to D. pteronyssinus high results were also prevalent in obese PCOS, with blood level (365,22 IU/mL) and (6.83 kU/L), respectively, also statistically significant. Conclusions: Observed predominance of cases with high levels of total IgE in the group of obese women with PCOS, 28 (70%) of the participants, whose mean blood concentration of the group was 365.22 IU/mL. In the analysis of Specific IgE between the groups, the allergen Dermatophagoides pteronyssinus showed greater dispersion and average the results of sensitization in the group of obese PCOS, whose mean blood concentration was 6.83 kU/l. Keywords: Obesity, Allergens and Polycystic Ovary Syndrome
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The sizing of nursing human resources is an essential management tool to meet the needs of the patients and the institution. Regarding to the Intensive Care Unit, where the most critical patients are treated and the most advanced life-support equipments are used, requiring a high number of skilled workers, the use of specific indicators to measure the workload of the team becomes necessary. The Nursing Activities Score is a validated instrument for measuring nursing workload in the Intensive Care Unit that has demonstrated effectiveness. It is a cross-sectional study with the primary objective of assessing the workload of nursing staff in an adult Intensive Care Unit through the application of the Nursing Activities Score. The study was conducted in a private hospital specialized in the treatment of patients with cancer, which is located in the city of Natal (Rio Grande do Norte – Brazil). The study was approved by the Research Ethics Committee of the hospital (Protocol number 558.799; CAAE 24966013.7.0000.5293). For data collection, a form of sociodemographic characteristics of the patients was used; the Nursing Activities Score was used to identify the workload of nursing staff; and the instrument of Perroca, which classifies patients and provides data related to the their need for nursing care, was also used. The collected data were analyzed using a statistical package. The categorical variables were described by absolute and relative frequency, while the number by median and interquartile range. Considering the inferential approach, the Spearman test, the Wald chi-square, Kruskal Wallis and Mann-Whitney test were used. The statistically significant variables were those with p values <0.05. The evaluation of the overall averages of NAS, considering the first 15 days of hospitalization, was performed by the analysis of Generalized Estimating Equations (GEE), with adjust for the variable length of hospitalization. The sample consisted of 40 patients, in the period of June to August 2014. The results showed a mean age of 62,1 years (±23,4) with a female predominance (57,5%). The most frequent type of treatment was clinical (60,0%), observing an average stay of 6,9 days (±6,5). Considering the origin, most patients (35%) came from the Surgical Center. There was a mortality rate of 27,5%. 277 measures of NAS score and Perroca were performed, and the averages of 69,8% (±24,1) and 22,7% (±4.2) were obtained, respectively. There was an association between clinical outcome and value of the Nursing Activities Score in 24 hours (p <0.001), and between the degree of dependency of patients and nursing workload (rp 0,653, p<0,001). The achieved workload of the nursing staff, in the analyzed period, was presented high, showing that hospitalized patients required a high demand for care. These findings create subsidies for sizing of staff and allocation of human resources in the sector, in order to achieve greater safety and patient satisfaction as a result of intensive care, as well as an environment conducive to quality of life for the professionals
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INTRODUCTION: The pregnancy and childbirth cause many changes in a woman's life, whether physical, hormonal, emotional or social. Such changes may affect the postural balance and the quality of life of women in pregnancy and may persist after delivery. To analyze changes in postural balance and quality of life in women in pregnancy and postpartum. METHODS: This study consisted of 47 women participants of the Course for Pregnant Women of the Department of Physical Therapy at UFRN, evaluated during pregnancy (2° or 3° trimester) and in the period 1-8 months postpartum. In all participants was evaluated the postural balance, the Balance Master® in five specific tests: (1) Modified Clinical Test of Sensory Interaction on Balance-MCTSIB; (2) Rhythmic Weight Shift Test - RWS (3) unilateral stance - US, (4) Sit to Stand - STS, and (5) Walk Across - WA. The quality of life (QoL) was assessed by applying the Quality Score of life Ferrans & Powers (IQVFP), both during pregnancy and in the postpartum period. For statistical analysis we used the Statistical Package for Social Sciences software for Personal Computer- SPSS (version 20.0), applying the tests: Shapiro-Wilk to assess the normality of the data; Chi-square to analyze the frequency of postural balance changes in the two groups of pregnancy and postpartum in both groups; McNemar test to analyze balance disorders frequency of related samples in the two time points; to compare the behavior of postural balance during pregnancy and postpartum, and to compare the QoL between the periods, we used the Wilcoxon test; and yet, the MannWhitney test to compare the QoL scores in the two groups of pregnancy and postpartum in both groups. We adopted p-value <0.05. RESULTS: Comparing the postural balance during pregnancy and postpartum in MSTSIB test has statistical difference in unstable surface with closed eyes (p=0.001) and in the US test, the speed of oscillation with right leg with eyes closed (p=0,03). Quality of life, there was statistical difference between the scores only among postpartum groups, the family domain (p=0.03); and to comparing pregnancy and postpartum in domain health and operation (p=0.02) and the Socioeconomic domain (p=0.01). CONCLUSIONS: It was observed that the balance changes present during pregnancy persist postpartum, and the quality of life is considered good by women, both during pregnancy and postpartum.
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Objective: Evaluate the determinants of morbidity and mortality in an obstetric intensive care unit and professional medical skills of students/residents at a university hospital. Methods: observational cross - sectional with 492 pregnant/pue rperal women and 261 students/residents. Patients were admitted to the obstetric intensive care unit during a year, being informed about the proposals of the study and a questionnaire was applied. The analysis was performed using Microsoft Excel 2013 and G raphPad6. Chi - square tests were used to evaluate risk factors and student t test evaluates resident/students' skills concerning the cognitive test and the Mini - Cex. Results: the main risk factors to near miss were: non - white race (OR = 2.527; RR = 2.342) ; marital status(married women) (OR = 7.968; RR = 7.113) , schooling (primary) (OR = 3.177 ; RR = 2.829) , from country town (OR = 4.643 ; RR = 4.087), low income (OR = 7014 ; RR = 5.554) , gestational hypertensive disorders (OR = 16.35 ; RR = 13.27) , re alization of pre - natal (OR = 5.023 ; RR = 4.254) and C - section before labor(OR = 39.21 ; RR = 31.25). In cognitive/Mini - cex analysis were noted significant difference in the performance of students on the subject (3.75 ± 0.93, 4.03 ± 0.94 and 4.88 ± 0.35). We still observed the best performance of residents, when compared to graduation students (p < 0.01). Conclusions: the prevalence of near miss was associated with socioeconomic/clinics factors and care issues, revealing the importance of interventions to improve these indicators. In addition, we suggest a better curriculum insertion of this subject in the medical Course disciplines due the importance to avoid the near miss through of adequacy of medical education.
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Currently, there is a great search for materials derived from renewable sources. The vegetable fibers as reinforcement for polymer matrixes, has been used as an alternative to replace synthetic fibres, being biodegradable and of low cost. The present work aims to develop a composite material with epoxy resin reinforced with curauá fibre with the addition of alumina trihydrate (aluminum hydroxide, Al(OH)3) as a flame retardant, which was used in proportions of 10 %, 20% and 30% of the total volume of the composite. The curauá fibers have gone through a cleaning process with an alkaline bath of sodium hydroxide (NaOH ), parallelized by hand and cut carding according to the default length . They were molded composites with fibers 30cm. Composites were molded in a Lossy Mold with unidirectional fibres in the proportion of 20% of the total volume of the composite. The composites were prepared in the Chemical Processing Laboratory of the Textile Engineering Department at UFRN. To measure the performance of the material, tests for the resistance to traction and flexion were carried out. with samples that were later analyzed in the Electronic Microscopy Apparatus (SEM ). The composites showed good mechanical properties by the addition of flame retardant and in some cases, leaving the composite more vulnerable to breakage. These mechanical results were analyzed by chi-square statistical test at the 5% significance level to check for possible differences between the composite groups. Flammability testing was conducted based on the standard Underwriters Laboratory 94 and the material showed a satisfactory result taking their average burn rate (mm / min) decreasing with increasing addition of the flame retardant composite.
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Objective Based on the system of reference and counter-reference and comprehensiveness in oral health care, we aimed to examine ways of refering users to Specialized Dental Care Centers (SDCC) and the interface between them and Primary Care. Methods This is a cross-sectional study carried out with users and dentists of SDCC in a metropolitan region of Northeast of Brazil. Analyses were descriptive, and the association test was done with chi-square. Results Six forms of entry to specialized service were identified: free demand (13.8 %) and reference by the Primary Care dentist (63.2 %) were most frequent. Users referred by the basic health unit dentist had more interest in making a counter-reference than the others (p<0.001, PR=4.65, 95 % CI: 2.74 to 7.91), while individuals without this referral had 1.49 times more difficulty obtaining care (95 % CI: 1.02 to 2.17). Referral procedures are a decisive factor for counter-references. However, the high demand for primary care services and the short supply these services can offer in the face of needs make SDCC performance difficult. Conclusion The analysis of oral health practices from the perspective of network modeling points to the service's need to establish protocols for regulation in a bid to improve access to and the quality of care provided.
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Objective Based on the system of reference and counter-reference and comprehensiveness in oral health care, we aimed to examine ways of refering users to Specialized Dental Care Centers (SDCC) and the interface between them and Primary Care. Methods This is a cross-sectional study carried out with users and dentists of SDCC in a metropolitan region of Northeast of Brazil. Analyses were descriptive, and the association test was done with chi-square. Results Six forms of entry to specialized service were identified: free demand (13.8 %) and reference by the Primary Care dentist (63.2 %) were most frequent. Users referred by the basic health unit dentist had more interest in making a counter-reference than the others (p<0.001, PR=4.65, 95 % CI: 2.74 to 7.91), while individuals without this referral had 1.49 times more difficulty obtaining care (95 % CI: 1.02 to 2.17). Referral procedures are a decisive factor for counter-references. However, the high demand for primary care services and the short supply these services can offer in the face of needs make SDCC performance difficult. Conclusion The analysis of oral health practices from the perspective of network modeling points to the service's need to establish protocols for regulation in a bid to improve access to and the quality of care provided.
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Omnibus tests of significance in contingency tables use statistics of the chi-square type. When the null is rejected, residual analyses are conducted to identify cells in which observed frequencies differ significantly from expected frequencies. Residual analyses are thus conditioned on a significant omnibus test. Conditional approaches have been shown to substantially alter type I error rates in cases involving t tests conditional on the results of a test of equality of variances, or tests of regression coefficients conditional on the results of tests of heteroscedasticity. We show that residual analyses conditional on a significant omnibus test are also affected by this problem, yielding type I error rates that can be up to 6 times larger than nominal rates, depending on the size of the table and the form of the marginal distributions. We explored several unconditional approaches in search for a method that maintains the nominal type I error rate and found out that a bootstrap correction for multiple testing achieved this goal. The validity of this approach is documented for two-way contingency tables in the contexts of tests of independence, tests of homogeneity, and fitting psychometric functions. Computer code in MATLAB and R to conduct these analyses is provided as Supplementary Material.