1. 2.

On its website, the National Center for Complementary and Alternative Medicine (NCCAM, a branch of NIH) offers comprehensive information about various complementary and alternative healing practices, including a summary of research findings for each practice. Echinacea is a flowering plant related to daisies with a long history of medicinal use, starting with Native Americans. Today it is the top-selling herbal remedy in the United States, mainly used against the common cold. In a double-blind experiment, healthy volunteers agreed to be exposed to common-cold-causing rhinovirus type 39. Three types of echinacea extracts were produced (labeled E1, E2, and E3 in the table). Subjects received either an echinacea extract or a placebo ("P") over two different periods: for seven consecutive days before viral exposure (infection and symptom prevention) and for seven consecutive days following exposure (symptom treatment). Among the variables studied were whether or not a subject became infected following viral exposure and whether or not infected subjects developed cold symptoms. The results are provided: Infected Not infected Cold symptoms No symptoms Treatment El then El E2 then E2 E3 then E3 P then E1 P then E2 P then E3 P then P To access the complete data set, click the link for your preferred software format: Excel Minitab JMP SPSS TI R Mac-TXT PC-TXT CSV CrunchIt! Running a chi-square test for each variable separately gave x2 = 4.745 and x2 = 7.120 for the first variable and the second variable, respectively. Select the correct summary of the overall findings from this study. O The study found no statistical evidence that any of the echinacea extract helps prevent the apparition of cold symptoms, nor that it helps ease cold symptoms. The study found evidence of an association between treatment and becoming infected following viral exposure, and also between treatment and developing cold symptoms after being infected. The study found no statistical evidence that any of the echinacea extract helps prevent the apparition of cold symptoms, but some of them help ease cold symptoms. The study provides proof that echinacea extracts are not useful in preventing the apparition of cold symptoms, nor do they help ease cold symptoms. Treatments Infected Not infected Cold symptoms No symptom E1 E1 5 15 18 2 E2 E2 3 E3 E3 PE1 PE2 6 PE3 7 PP Question 15 of 15 > Acne is a common skin disease that affects most adolescents and can continue into adulthood. A study compared the effectiveness of three acne treatments and a placebo, all in gel form, applied twice daily for twelve weeks. The study's 517 teenage volunteers were randomly assigned to one of the four treatments. Success was assessed as clear or almost clear skin at the end of the twelve-week period. The Minitab output gives counts and chi-square output for this study. E Session Chi-Square Test: epiduo, adapalene, benzoyl peroxide, placebo Expected counts are printed below observed counts Chi-Square contributions are printed below expected counts epiduo adapalene placebo Total Success 32 18 benzoy2 peroxide 18 20.75 0.365 20.75 6.099 20.61 0.331 9.89 3.506 Failure 117 128.25 0.987 130 127.39 0.054 131 128.25 0.059 67 61.11 0.567 Total 149 148 149 71 Chi-Sq - 11.967, DF - 3, P-Value - 0.007 Is there significant evidence that the four treatments perform differently? Use the four-step process for your analysis. STATE: Is type of acne treatment associated with clearer skin? PLAN: Choose the hypotheses that we should test. O H : Acne treatments do not work versus H,: The acne treatment outcome is random O H,: There is an association between acne treatment type and outcome versus H, H, is not true Ho: There is no association between acne treatment type and outcome versus HQ: H, is not true O Ho: There is no association between acne treatment type and outcome versus H,: The acne treatment outcome is random SOLVE: The Minitab output for the xtest is given. Find the success rate for cach of the four treatments. (Enter your answers as a percentage rounded to one decimal place.) successepiduo = success adapalene = succesShenzoyl perogide success placebo Choose the best explanation from the output results, O The largest x components are for the count of success in the epiduo group and the adapalene group: Subjects in the cpiduo group had less successes than expected, whereas subjects in the placebo group had more successes than expected The largest x? component is for the count of success in the epiduo group: Subjects in the placebo group had less successes than expected, whereas subjects in the benzoyl peroxide group had fewer successes than expected. The largest xcomponents are for the count of success in the epiduo group and the placebo group: Subjects in the epiduo group had more successes than expected, whereas subjects in the placebo group had fewer successes than expected. The largest x? components are for the count of success in the adapalenc group and the placcbo group: Subjects in the adapalene group had more successes than expected, whereas subjects in the placebo group had fewer successes than expected. O CONCLUDE: What conclusion can we make? Select the best explanation. O O There is strong evidence of a relationship between treatment type and outcome. Adapalene has the highest success rate, whereas the placebo group had the lowest success rate. There is strong evidence of a relationship between treatment type and outcome. Epiduo has the highest success rate, whereas the placebo group had the lowest success rate. There is weak evidence of a relationship between treatment type and outcome. Epiduo has the highest success rate, whereas the placebo group had the lowest success rate. There is weak evidence of a relationship between treatment type and outcome. Benzoyl peroxide has the highest success rate, whereas the adapalene group had the lowest success rate. O O On its website, the National Center for Complementary and Alternative Medicine (NCCAM, a branch of NIH) offers comprehensive information about various complementary and alternative healing practices, including a summary of research findings for each practice. Echinacea is a flowering plant related to daisies with a long history of medicinal use, starting with Native Americans. Today it is the top-selling herbal remedy in the United States, mainly used against the common cold. In a double-blind experiment, healthy volunteers agreed to be exposed to common-cold-causing rhinovirus type 39. Three types of echinacea extracts were produced (labeled E1, E2, and E3 in the table). Subjects received either an echinacea extract or a placebo ("P") over two different periods: for seven consecutive days before viral exposure (infection and symptom prevention) and for seven consecutive days following exposure (symptom treatment). Among the variables studied were whether or not a subject became infected following viral exposure and whether or not infected subjects developed cold symptoms. The results are provided: Infected Not infected Cold symptoms No symptoms Treatment El then El E2 then E2 E3 then E3 P then E1 P then E2 P then E3 P then P To access the complete data set, click the link for your preferred software format: Excel Minitab JMP SPSS TI R Mac-TXT PC-TXT CSV CrunchIt! Running a chi-square test for each variable separately gave x2 = 4.745 and x2 = 7.120 for the first variable and the second variable, respectively. Select the correct summary of the overall findings from this study. O The study found no statistical evidence that any of the echinacea extract helps prevent the apparition of cold symptoms, nor that it helps ease cold symptoms. The study found evidence of an association between treatment and becoming infected following viral exposure, and also between treatment and developing cold symptoms after being infected. The study found no statistical evidence that any of the echinacea extract helps prevent the apparition of cold symptoms, but some of them help ease cold symptoms. The study provides proof that echinacea extracts are not useful in preventing the apparition of cold symptoms, nor do they help ease cold symptoms. Treatments Infected Not infected Cold symptoms No symptom E1 E1 5 15 18 2 E2 E2 3 E3 E3 PE1 PE2 6 PE3 7 PP Question 15 of 15 > Acne is a common skin disease that affects most adolescents and can continue into adulthood. A study compared the effectiveness of three acne treatments and a placebo, all in gel form, applied twice daily for twelve weeks. The study's 517 teenage volunteers were randomly assigned to one of the four treatments. Success was assessed as clear or almost clear skin at the end of the twelve-week period. The Minitab output gives counts and chi-square output for this study. E Session Chi-Square Test: epiduo, adapalene, benzoyl peroxide, placebo Expected counts are printed below observed counts Chi-Square contributions are printed below expected counts epiduo adapalene placebo Total Success 32 18 benzoy2 peroxide 18 20.75 0.365 20.75 6.099 20.61 0.331 9.89 3.506 Failure 117 128.25 0.987 130 127.39 0.054 131 128.25 0.059 67 61.11 0.567 Total 149 148 149 71 Chi-Sq - 11.967, DF - 3, P-Value - 0.007 Is there significant evidence that the four treatments perform differently? Use the four-step process for your analysis. STATE: Is type of acne treatment associated with clearer skin? PLAN: Choose the hypotheses that we should test. O H : Acne treatments do not work versus H,: The acne treatment outcome is random O H,: There is an association between acne treatment type and outcome versus H, H, is not true Ho: There is no association between acne treatment type and outcome versus HQ: H, is not true O Ho: There is no association between acne treatment type and outcome versus H,: The acne treatment outcome is random SOLVE: The Minitab output for the xtest is given. Find the success rate for cach of the four treatments. (Enter your answers as a percentage rounded to one decimal place.) successepiduo = success adapalene = succesShenzoyl perogide success placebo Choose the best explanation from the output results, O The largest x components are for the count of success in the epiduo group and the adapalene group: Subjects in the cpiduo group had less successes than expected, whereas subjects in the placebo group had more successes than expected The largest x? component is for the count of success in the epiduo group: Subjects in the placebo group had less successes than expected, whereas subjects in the benzoyl peroxide group had fewer successes than expected. The largest xcomponents are for the count of success in the epiduo group and the placebo group: Subjects in the epiduo group had more successes than expected, whereas subjects in the placebo group had fewer successes than expected. The largest x? components are for the count of success in the adapalenc group and the placcbo group: Subjects in the adapalene group had more successes than expected, whereas subjects in the placebo group had fewer successes than expected. O CONCLUDE: What conclusion can we make? Select the best explanation. O O There is strong evidence of a relationship between treatment type and outcome. Adapalene has the highest success rate, whereas the placebo group had the lowest success rate. There is strong evidence of a relationship between treatment type and outcome. Epiduo has the highest success rate, whereas the placebo group had the lowest success rate. There is weak evidence of a relationship between treatment type and outcome. Epiduo has the highest success rate, whereas the placebo group had the lowest success rate. There is weak evidence of a relationship between treatment type and outcome. Benzoyl peroxide has the highest success rate, whereas the adapalene group had the lowest success rate. O O