Multiple Comparison Procedures Research Articles

Generalized multiple contrast tests in dose-response studies.

In the process of developing drugs, proof-of-concept studies can be helpful in determining whether there is any evidence of a dose-response relationship. A global test for this purpose that has gained popularity is a component of the multiple comparisons procedure with modeling techniques (MCP-Mod), which involves the specification of a candidate set of several plausible dose-response models. For each model, a test is performed for significance of an optimally chosen contrast among the sample means. An overall P-value is obtained from the distribution of the maximum of the contrast statistics. This is equivalent to basing the test on the minimum of the P-values arising from these contrast statistics and, hence, can be viewed as a method for combining dependent P-values. We generalize this idea to the use of different statistics for combining the dependent P-values, such as Fisher's combination method or the inverse normal combination method. Simulation studies show that the generalized multiple contrast tests (GMCTs) based on the Fisher and inverse normal methods are generally more powerful than the MCP-Mod procedure based on the minimum of the P-values except for cases where the true dose-response model is, in a sense, near the extremes of the candidate set of dose-response models. The proposed GMCTs can also be used for model selection and dosage selection by employing a closed testing procedure.

A simple data-driven fallback procedure for multiple comparisons

We propose a data-driven fallback procedure to combine the positive aspects of both data-driven multiple comparison procedures and those relying on predetermined strategies. The proposed procedure tests the hypotheses based on the ordering of p-values, but the significance level of the test at each sequential step is accumulated in the manner of the fallback procedure. It is proven that the new procedure strongly controls the familywise error rate and is uniformly more powerful than the weighted Holm procedure for more than two hypotheses. The simulation study shows that the new procedure is more powerful than the fallback in most cases.

A multiple comparison procedure for dose‐finding trials with subpopulations

Identifying subgroups of patients with an enhanced response to a new treatment has become an area of increased interest in the last few years. When there is knowledge about possible subpopulations with an enhanced treatment effect before the start of a trial it might be beneficial to set up a testing strategy, which tests for a significant treatment effect not only in the full population, but also in these prespecified subpopulations. In this paper, we present a parametric multiple testing approach for tests in multiple populations for dose‐finding trials. Our approach is based on the MCP‐Mod methodology, which uses multiple comparison procedures (MCPs) to test for a dose–response signal, while considering multiple possible candidate dose–response shapes. Our proposed methods allow for heteroscedastic error variances between populations and control the family‐wise error rate over tests in multiple populations and for multiple candidate models. We show in simulations that the proposed multipopulation testing approaches can increase the power to detect a significant dose–response signal over the standard single‐population MCP‐Mod, when the specified subpopulation has an enhanced treatment effect.

A gate-keeping test for selecting adaptive interventions under general designs of sequential multiple assignment randomized trials

This article proposes a method to overcome limitations in current methods that address multiple comparisons of adaptive interventions embedded in sequential multiple assignment randomized trial (SMART) designs. Because a SMART typically consists of numerous adaptive interventions, inferential procedures based on pairwise comparisons of all may suffer a substantial loss in power after accounting for multiplicity. Meanwhile, traditional methods for multiplicity adjustments in comparing non-adaptive interventions require prior knowledge of correlation structures, which can be difficult to postulate when analyzing SMART data of adaptive interventions. To address the multiplicity issue, we propose a likelihood-based omnibus test that compares all adaptive interventions simultaneously, and apply it as a gate-keeping test for further decision making. Specifically, we consider a selection procedure that selects the adaptive intervention with the best observed outcome only when the proposed omnibus test reaches a pre-specified significance level, so as to control false positive selection. We derive the asymptotic distribution of the test statistic on which a sample size formula is based. Our simulation study confirms that the asymptotic approximation is accurate with a moderate sample size, and shows that the proposed test outperforms existing multiple comparison procedures in terms of statistical power. The simulation results also suggest that our selection procedure achieves a high probability of selecting a superior adaptive intervention. The application of the proposed method is illustrated with a real dataset from a depression management study.

66 Future-proofing the feedyard workforce: Survey of Texas beef cattle stockpeople indicates positive attitudes towards animals and the workplace while highlighting opportunities for improvement

Abstract A survey was administered to Texas cattle feedyard employees (n = 111) from 31 different operations measuring stockperson perception, job satisfaction, and socioeconomic status using Likert statements and multiple-choice questions. Differences among employment roles (manager, pen rider, processor, doctor) were evaluated using a Kruskal-Wallis test followed by a Multiple Comparison procedure. Managers more strongly agreed that “beef cattle are not dirty” than doctors (P = 0.03) and that “cattle behavior is affected by the way we treat them” than pen riders (P = 0.002) or processors (P = 0.01). Managers were less likely than doctors, pen riders and processors to believe they have too many cattle to look after (P = 0.05, P = 0.006 and P = 0.01, respectively). Pen riders reported less confidence in performing euthanasia than doctors (P = 0.02) and managers (P = 0.02), and, along with processors, agreed that cattle were not always euthanized in a timely manner (P = 0.02 and P = 0.02, respectively). While all roles viewed Holstein cattle unfavorably (P < 0.001), processors viewed them more positively than pen riders (P = 0.05) and managers (P = 0.001). Socioeconomic results showed that Texas feedyards have a dedicated, passionate workforce, with 43% of participants having worked in the industry for 9+ years and 49% of participants working at cattle feedyards because they enjoy working with animals. Unfortunately, it was evident that stockpeople are underpaid (57% of participants making between $10–15/hr) and overworked (76% of participants working 50+ hrs/wk). Survey responses identified critical role-dependent knowledge gaps and biases. A disconnect was observed among compensation, workload, and the duration of time stockpeople spend interacting with cattle. Increasing industry investment in feedyard employees and providing breed-specific and employee role-specific education may promote an encouraging workplace that ensures cattle experience good welfare.

15 Future-proofing the feedyard workforce: Survey of Texas beef cattle stockpeople indicates positive attitudes towards animals and the workplace while highlighting opportunities for improvement

Abstract A survey was administered to Texas cattle feedyard employees (n = 111) from 31 different operations measuring stockperson perception, job satisfaction and socioeconomic status using Likert statements and multiple-choice questions. Differences among employment roles (manager, pen rider, processor, doctor) were evaluated using a Kruskal-Wallis test followed by a Multiple Comparison procedure. Managers more strongly agreed that “beef cattle are not dirty” than doctors (P = 0.03) and that “cattle behavior is affected by the way we treat them” than pen riders (P = 0.002) or processors (P = 0.01). Managers were less likely than doctors, pen riders, and processors to believe they have too many cattle to look after (P = 0.05, P = 0.006 and P = 0.01, respectively). Pen riders reported less confidence in performing euthanasia than doctors (P = 0.02) and managers (P = 0.02), and, along with processors, agreed that cattle were not always euthanized in a timely manner (P = 0.02 and P = 0.02, respectively). While all roles viewed Holstein cattle unfavorably (P < 0.001), processors viewed them more positively than pen riders (P = 0.05) and managers (P = 0.001). Socioeconomic results showed that Texas feedyards have a dedicated, passionate work force, with 43% of participants having worked in the industry for 9+ years and 49% of participants working at cattle feedyards because they enjoy working with animals. Unfortunately, it was evident that stockpeople are underpaid (57% of participants making between $10–15/hr) and overworked (76% of participants working 50+ hrs/wk). Survey responses identified critical role-dependent knowledge gaps and biases. A disconnect was observed among compensation, workload, and the duration of time stockpeople spend interacting with cattle. Increasing industry investment in feedyard employees and providing breed-specific and employee role-specific education may promote an encouraging workplace that ensures cattle experience good welfare.

Optimization of Bayesian Multiple Comparison Tests dbayes and pbayes in R Code

A estatística experimental utiliza procedimentos de comparações múltiplas (PCM) a fim de verificar se há diferença entre os tratamentos em análise. Entretanto, a presença de dados desbalanceados e casos de heterogeneidade de variâncias influencia negativamente o desempenho dos testes mais utilizados. Os testes dbayes e pbayes foram implementados anteriormente no contexto dos delineamentos inteiramente casualizados por um dos autores. Esses testes são válidos para casos em que as pressuposições da análise de variância são atendidas ou não, com ou sem balanceamento. O presente artigo tem por objetivo realizar uma otimização da função Bayes, em código R, que permite a realização destes testes. Para validar a otimização, comparou-se o código otimizado com o código anterior e utilizou três situações reais: uma atendendo a todas as pressuposições, as outras duas com dados desbalanceados e com número diferente de tratamentos. A função Bayes otimizada propicia que os testes dbayes e pbayes tenham bons resultados em condições de atendimento das pressuposições e balanceamento. Estes testes podem ser utilizados satisfatoriamente nas situações de não atendimento das pressuposições. Nos casos de dados desbalanceados, com um pequeno número de tratamentos, o teste dbayes apresenta resultado superior ao teste de Tukey-Kramer.

Effect of Neladenoson Bialanate on Exercise Capacity Among Patients With Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) lacks effective treatments. Based on preclinical studies, neladenoson bialanate, a first-in-class partial adenosine A1 receptor agonist, has the potential to improve several heart failure-related cardiac and noncardiac abnormalities but has not been evaluated to treat HFpEF. To determine whether neladenoson improves exercise capacity, physical activity, cardiac biomarkers, and quality of life in patients with HFpEF and to find the optimal dose. Phase 2b randomized clinical trial conducted at 76 centers in the United States, Europe, and Japan. Patients (N = 305) with New York Heart Association class II or III HFpEF with elevated natriuretic peptide levels were enrolled between May 10, 2017, and December 7, 2017 (date of final follow-up: June 20, 2018). Participants were randomized (1:2:2:2:2:3) to neladenoson (n = 27 [5 mg], n = 50 [10 mg], n = 51 [20 mg], n = 50 [30 mg], and n = 51 [40 mg]) or matching placebo (n = 76) for 20 weeks of treatment. The primary end point was change in 6-minute walk test distance from baseline to 20 weeks (minimal clinically important difference, 40 m). Key safety measures included bradyarrhythmias and adverse events. To evaluate the effects of varying doses of neladenoson, a multiple comparison procedure with 5 modeling techniques (linear, Emax, 2 variations of sigmoidal Emax, and quadratic) was used to evaluate diverse dose-response profiles. Among 305 patients who were randomized (mean age, 74 years; 160 [53%] women; mean 6-minute walk test distance, 321.5 m), 261 (86%) completed the trial and were included in the primary analysis. After 20 weeks of treatment, the mean absolute changes from baseline in 6-minute walk test distance were 0.2 m (95% CI, -12.1 to 12.4 m) for the placebo group; 19.4 m (95% CI, -10.8 to 49.7 m) for the 5 mg of neladenoson group; 29.4 m (95% CI, 3.0 to 55.8 m) for 10 mg of neladenoson group; 13.8 m (95% CI, -2.3 to 29.8 m) for 20 mg of neladenoson group; 16.3 m (95% CI, -1.1 to 33.6 m) for 30 mg of neladenoson group; and 13.0 m (95% CI, -5.9 to 31.9 m) for 40 mg of neladenoson group. Because none of the neladenoson groups achieved the clinically relevant 40-m increase in 6-minute walk test distance from baseline, an optimal dose of neladenoson was not identified. There was no significant dose-response relationship for the change in 6-minute walk test distance among the 5 different dose-response models (P = .05 for Emax; P = .18 for quadratic; P = .21 for sigmoidal Emax 1; P = .39 for linear; and P = .52 for sigmoidal Emax 2). Serious adverse events were similar among the neladenoson groups (61/229 [26.6%]) and the placebo group (21/76 [27.6%]). Among patients with HFpEF, there was no significant dose-response relationship detected for neladenoson with regard to the change in exercise capacity from baseline to 20 weeks. In light of these findings, novel approaches will be needed if further development of neladenoson for the treatment of patients with HFpEF is pursued. ClinicalTrials.gov Identifier: NCT03098979.

Provision of Paid Web-Based Medical Consultation in China: Cross-Sectional Analysis of Data From a Medical Consultation Website.

BackgroundWeb-based medical consultation, which has been adopted by patients in many countries, requires a large number of doctors to provide services. However, no study has provided an overall picture of the doctors who provide online services.ObjectiveThis study sought to examine doctors’ participation in medical consultation practice in an online consultation platform. This paper aimed to address the following questions: (1) which doctors provide Web-based consultation services, (2) how many patients do the doctors get online, and (3) what price do they charge. We further explored the development of market segments in various departments and various provinces.MethodsThis study explored the dataset including all doctors providing consultation services in their spare time on a Chinese Web-based consultation platform. We also brought in statistics for doctors providing offline consultations in China. We made use of Bonferroni multiple comparison procedures and z test to compare doctors in each group.ResultsThere are 88,308 doctors providing Web-based consultation in their spare time on Haodf, accounting for 5.25% (88,308/1,680,062) of all doctors in China as of September 23, 2017. Of these online doctors, 49.9% (44,066/88,308) are high-quality doctors having a title of chief physician or associate chief physician, and 84.8% (74,899/88,308) come from the top, level 3, hospitals. Online doctors had an average workload of 0.38 patients per doctor per day, with an online and offline ratio of 1:14. The average price of online consultation is ¥32.3. The online ratios for the cancer, internal medicine, ophthalmology-otorhinolaryngology, psychiatry, gynecology-obstetrics-pediatrics, dermatology, surgery, and traditional Chinese medicine departments are 16.1% (2,983/18,481), 4.4% (16,231/372,974), 6.3% (8,389/132,725), 9.5% (1,600/16,801), 5.8% (12,955/225,128), 18.0% (3,334/18,481), 10.8% (24,030/223,448), and 3.8% (8,393/22,3448), respectively. Most provinces located in eastern China have more than 4000 doctors online. The online workloads for doctors from most provinces range from 0.3 to 0.4 patients per doctor per day. In most provinces, doctors’ charges range from ¥20 to ¥30.ConclusionsQuality doctors are more likely to provide Web-based consultation services, get more patients, and charge higher service fees in an online consultation platform. Policies and promotions could attract more doctors to provide Web-based consultation. The online submarket for the departments of dermatology, psychiatry, and gynecology-obstetrics-pediatrics developed better than other departments such as internal medicine and traditional Chinese medicine. The result could be a reference for policy making to improve the medical system both online and offline. As all the data used for analysis were from a single website, the data might be biased and might not be a representative national sample of China.

Familywise and per-family error rates of multiple comparison procedures.

In multiple testing scenarios, one of the more popular definitions of the error rate is the familywise error rate (FWER). The per-family error rate (PFER) is often not considered. The PFER deserves more attention than it currently receives. Both of these concepts were formulated by Tukey. We highlight some of the good and bad qualities of the FWER and the PFER. We find the FWER and PFER for four commonly used multiple comparison procedures.

A multi-treatment response adaptive design for ordinal categorical responses.

A multi-treatment response adaptive procedure is developed considering "comparison with the best" philosophy of multiple comparison procedures for clinical trials with ordinal categorical responses, when there is no shared control. For each response category, we arbitrarily create two outcome groups; one by combining the categories more favorable to it and the other by merging the categories at most as favorable to it and hence define the odds (i.e. cumulative odds). Pairwise ratios of such odds (i.e. cumulative odds ratios) based on pairs of treatments are combined conveniently to derive a measure of relative superiority and hence the allocation probability functions. For practical implementation, we suggest response-adaptive randomization (RAR), that is, update the allocation probabilities dynamically using the available allocation and response information to favor the treatment doing better. Empirical as well as large sample properties following the randomization are investigated in detail. Moreover, a real clinical trial with trauma patients is redesigned using the proposed RAR to envisage practical applicability.

One stage multiple comparisons with the control for exponential mean lifetimes based on doubly censored samples under heteroscedasticity

In the field of ranking and selection, the quality engineer would like to compare the mean lifetimes of several treatment populations with the control for exponential distribution. In most cases, the scale parameters are unknown and unequal. We proposed a one-stage multiple comparison procedure for comparing k-1 treatment exponential mean lifetimes with the control based on doubly censored samples under heteroscedasticity. The tables of critical values for the multiple comparison procedures are listed for the practical use. At last, one example of duration of remission for 20 patients each taking one of four drugs for the treatment of leukemia is given to demonstrate the application of our proposed method.

Multiple comparison procedures for finding non-maximum normal means

In this study, we discuss multiple comparison procedures for finding normal means which are not maximum among several normal means. Specifically, we propose the single step procedure, the sequentially rejective step down procedure and the step up procedure. For the single step procedure we determine the critical value for a specified significance level. For the sequentially rejective step down procedure and the step up procedure we determine the critical value at each step of the test for a specified significance level. For three procedures we formulate the power of the test under a specified alternative hypothesis. We give some numerical examples regarding critical values and power of the test intended to compare three procedures.

Essential Statistical Concepts for Research in Speech, Language, and Hearing Sciences.

Purpose Clinicians depend on the accuracy of research in the speech, language, and hearing sciences to improve assessment and treatment of patients with communication disorders. Although this work has contributed to great advances in clinical care, common statistical misconceptions remain, which deserve closer inspection in the field. Challenges in applying and interpreting traditional statistical methods with behavioral data from humans have led to difficulties with replication and reproducibility in other allied scientific fields, including psychology and medicine. The importance of research in our fields of study for advancing science and clinical care for our patients means that the choices of statistical methods can have far-reaching, real-world implications. Method The goal of this article is to provide an overview of fundamental statistical concepts and methods that are used in the speech, language, and hearing sciences. Results We reintroduce basic statistical terms such as the p value and effect size, as well as recommended procedures for model selection and multiple comparisons. Conclusions Research in the speech, language, and hearing sciences can have a profound positive impact on the lives of individuals with communication disorders, but the validity of scientific findings in our fields is enhanced when data are analyzed using sound statistical methods. Misunderstanding or misinterpretation of basic statistical principles may erode public trust in research findings. Recommendations for practices that can help minimize the likelihood of errors in statistical inference are provided. Supplemental Material https://doi.org/10.23641/asha.7849223.

A random decision for testing of the homogeneity of normal means against the tree order alternative

Consider the problem of testing the homogeneity of k + 1 normal means under the tree order restriction. In this paper, we propose new multiple comparisons procedures for testing of the tree order constraint. New test procedures with the corresponding simultaneous confidence intervals are motivated by some new estimation methods which are constructed based on a random decision and the Bayesian approach. Also, these procedures are developed for two-sided tree order alternatives. We compare the performance of the proposed methods with some existing test procedures, such as likelihood ratio test and some multiple comparisons tests for the tree order constraint. In some cases, the gains in power due to the proposed procedures can be substantial. The results for two sided alternative are similar to the one-sided hypotheses and two new procedures perform well for almost every configuration. We illustrate the efficiency of the proposed methods by analyzing of the two bioassay numerical examples.

Sudden gains in cognitive behavioral therapy among children and adolescents with obsessive compulsive disorder

Background and objectivesThis study examined the occurrence of sudden gains (or reversal of gains) among children with obsessive-compulsive disorder (OCD) during the course of cognitive-behavioral therapy (CBT), as well as the association of sudden gains with treatment response, treatment group, and pre-treatment clinical characteristics. MethodsThe sample consisted of 136 youth (ages 7–17) with a primary diagnosis of OCD who were randomized in a double-blinded fashion to 10 sessions of CBT with augmentation of either d-cycloserine or placebo. Sudden gain status was determined based on clinician-rated obsessive-compulsive symptom severity, which was collected on 9 occasions across the study period. Results42.6% of youth experienced at least one sudden gain, which tended to occur either after starting exposure and response prevention or towards the end of treatment. After applying the Benjamini-Hochberg procedure for multiple comparisons, there were no significant pre-treatment predictors of sudden gains and only reduced insight predicted the reversal of gains. Individuals with at least one sudden gain had improved overall treatment outcomes, measured both by reduction in OCD symptom severity, and by global illness severity. LimitationsSeveral clinical constructs were not examined. Symptomatology was not assessed at every treatment session. Differences in those who achieved sudden gains and those who did not may be obscured. There is the possibility that a sudden gain reflected a scoring error generated by an optimistic or inaccurate report. Finally, a relatively homogenous sample may limit the generalizability of results. ConclusionsThe course of CBT for pediatric OCD is variable with many children experiencing sudden gains, but a sizable percentage experience a reversal of gains which was related to reduced insight. Sudden gains tended to occur after starting exposure and response prevention and towards the end of treatment. TrialsregistrationClinicaltrialsgovRegistry:NCT00864123. https://www.clinicaltrials.gov/ct2/show/NCT00864123.

Clinical Setting Differences in Third-Year Medical Students’ Perceptions of “Ownership”

Ownership in clinical settings is a construct that be described as feelings of responsibility and accountability towards a patient, which has potential implications for patient safety and care. Researchers were interested in examining differences in students' perception of ownership across main and regional campuses. The purpose of this study is to assess third-year students' perception of "ownership" during their clerkship rotations in different clinical settings. Items from a validated instrument on psychological ownership were adopted to suit a clinical environment. Scores on each of the sub-scales of: a) Territoriality, b) Accountability, c) Self-efficacy, d) Belongingness, and e) Self-Identification were calculated by averaging the items. The survey was administered to 233 third-year medical students multiple times throughout the academic year. Responses from regional campus or community provider settings were compared to the main campus. To examine students' psychological ownership scores in different clinical settings, analysis of variance (ANOVA), was performed. A Tukey-Kramer multiple comparison procedure was used to examine post hoc pair-wise differences between two clinical settings. We received 265 of responses from 95 of responders. There were no statistically significant differences between campuses for Territoriality scores. On Self-Efficacy, Accountability, Self-Identification and Belongingness scales other community providers and regional campuses had significantly higher scores than main campus (p<0.05). Follow up ANOVA analysis were performed for all scales on individual items resulting in 1/5 for Accountability, 2/6 on Self-Efficacy, 5/5 on Belongingness, and 6/7 for Self-Identification been statistically significant.
 Ownership is considered an important aspect of patient care, patient safety, professional identity formation, etc., yet researchers have not examined how clinical settings impact students' perceptions of patient ownership during their clerkship years. Our study is the first step to operationalize and conceptualize ownership, its development over time, and differences in clinical experiences.
 
 None of the authors has a conflict of interest. This study was approved by our institution’s Institutional Review Board.

Clinical Setting Differences in Third-Year Medical Students’ Perceptions of “Ownership”

Ownership in clinical settings is a construct that be described as feelings of responsibility and accountability towards a patient, which has potential implications for patient safety and care. Researchers were interested in examining differences in students' perception of ownership across main and regional campuses. The purpose of this study is to assess third-year students' perception of "ownership" during their clerkship rotations in different clinical settings. Items from a validated instrument on psychological ownership were adopted to suit a clinical environment. Scores on each of the sub-scales of: a) Territoriality, b) Accountability, c) Self-efficacy, d) Belongingness, and e) Self-Identification were calculated by averaging the items. The survey was administered to 233 third-year medical students multiple times throughout the academic year. Responses from regional campus or community provider settings were compared to the main campus. To examine students' psychological ownership scores in different clinical settings, analysis of variance (ANOVA), was performed. A Tukey-Kramer multiple comparison procedure was used to examine post hoc pair-wise differences between two clinical settings. We received 265 of responses from 95 of responders. There were no statistically significant differences between campuses for Territoriality scores. On Self-Efficacy, Accountability, Self-Identification and Belongingness scales other community providers and regional campuses had significantly higher scores than main campus (p<0.05). Follow up ANOVA analysis were performed for all scales on individual items resulting in 1/5 for Accountability, 2/6 on Self-Efficacy, 5/5 on Belongingness, and 6/7 for Self-Identification been statistically significant.
 Ownership is considered an important aspect of patient care, patient safety, professional identity formation, etc., yet researchers have not examined how clinical settings impact students' perceptions of patient ownership during their clerkship years. Our study is the first step to operationalize and conceptualize ownership, its development over time, and differences in clinical experiences.
 
 None of the authors has a conflict of interest. This study was approved by our institution’s Institutional Review Board.

Evaluation of the Texas Feed Yard Workforce: Survey of Stockperson Attitudes and Perceptions towards Euthanasia, Animal Care and Employee Value

A survey was administered to Texas cattle feedyard employees (n =111) from 31 different operations measuring stockperson perception, job satisfaction and socioeconomic status using Likert statements and multiple-choice questions. Differences among employment roles (manager, pen rider, processor (those who vaccinate and implant incoming calves), doctor (non-veterinarians)) were evaluated using a Kruskal-Wallis test followed by a Multiple Comparison procedure. Managers strongly agreed with the statement “beef cattle are not dirty” more than doctors (P = 0.03) and that “cattle behavior is affected by the way we treat them” than pen riders (P = 0.002) or processors (P = 0.01). Managers were less likely than doctors, pen riders and processors to believe they have too many cattle to look after (P = 0.05, P = 0.006 and P = 0.01, respectively). Pen riders reported less confidence in performing euthanasia than doctors (P = 0.02) and managers (P = 0.02) and, along with processors, agreed that cattle were not always euthanized in a timely manner (P = 0.02 and P = 0.02, respectively). While all roles viewed Holstein cattle unfavorably (P < 0.001), processors viewed them more positively than pen riders (P = 0.05) and managers (P = 0.001). Socioeconomic results showed that Texas feedyards have a dedicated, passionate work force, with 43% of participants having worked in the industry for 9+ years and 49% of participants working at cattle feedyards because they enjoy working with animals. Unfortunately, it was evident that stock people are underpaid (57% of participants making between $10-15/hr) and overworked (76% of participants working 50+ hrs/week). Survey responses identified critical role-dependent knowledge gaps and biases. A disconnect was observed among compensation, workload and the duration of time stock people spend interacting with cattle. Increasing industry investment in feedyard employees and providing breed-specific and employee role-specific education may promote an encouraging workplace that ensures feedlot cattle experience good welfare.

Efecto de la fertilización de un cultivar de Medicago Sativa l. en la en la granja Santa Inés

The present investigation was carried out in the farm Santa Inés of the Academic Unit of Agricultural Sciences of the Universidad Técnica de Machala. A completely random design was used with 6 columns, each column with 40 experimental units giving a total of 240, using in each experimental unit 10 seeds of alfalfa for evaluation. The treatments were: T1 (without compost or fertilizer), T2 (with chemical fertilizer), and T3 (with compost), the evaluated variables were: weight of the biomass, number of leaves, and size of the plants. The Multivariate Variance Analysis was used for the study variables and to determine which factors have a statistically significant effect, prior to the verification of the Normality and Homogeneity assumptions. The method used to discriminate between the means was Duncan's multiple comparison procedure. The objective was to evaluate the effect of two fertilizations on M. sativa, using a chemical fertilizer and an organic fertilizer. The results show that the amount of biomass, the size of the plant and the number of leaves at the first cut after applying the respective treatment, does not differ so much with the use of YaraMila COMPLEX and compost.