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The drug diflunisal is used to treat mild to moderate pain due to osteoarthritis (OA) and rheumatoid arthritis (RA). The ocular effects of diflunisal had not been considered until a study was conducted on its effect on intraocular pressure in glaucoma patients who were already receiving maximum therapy for glaucoma [5].
Compute 95% CIs for the
Suppose the change (mean ± sd ) in intraocular pressure after administration of diflunisal (follow-up – baseline) among 10 patients whose standard therapy was methazolamide and topical glaucoma medications was −1.6 ± 1.5 mm Hg. Assess the statistical significance of the results.
The change in intraocular pressure after administration of diflunisal among 30 patients whose standard therapy was topical drugs only was −0.7 ± 2.1 mm Hg. Assess the statistical significance of these results.
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- Overproduction of uric acid in the body can be an indication of cell breakdown. This may be an advance indication of illness such as gout, leukemia, or lymphoma. Over a period of months, anadult male patient has taken eight blood tests for uric acid. The mean concentration was ?̅= 5.35mg/dl. The distribution of uric acid in healthy adult males can be assumed to be normal, with σ = 1.85 mg/dl.a. Find a 90% confidence interval for the population mean concentration of uric acid in this patient’s blood. What is the margin of error?b. Find a 99% confidence interval for the population mean concentration of uric acid in this patient’s blood. What is the margin of error? Compare the lengths of the confidence intervals for parts (a) and (b). As the confidence levelsincrease, do the confidence intervals increase in length?arrow_forwardOverproduction of uric acid in the body can be an indication of cell breakdown. This may be an advance indication of illness such as gout, leukemia, or lymphoma.+ Over a period of months, an adult male patient has taken eleven blood tests for uric acid. The mean concentration was x = 5.29 mg/dl. The distribution of uric acid in healthy adult males can be assumed to be normal, with o = 1.87 mg/dl. (a) Find a 95% confidence interval for the population mean concentration of uric acid in this patient's blood. What is the margin of error? (Round your answers to two decimal places.) lower limit upper limit margin of error (b) What conditions are necessary for your calculations? (Select all that apply.) o is known o is unknown normal distribution of uric acid O uniform distribution of uric acid On is large (c) Interpret your results in the context of this problem. O We are 5% confident that the true uric acid level for this patient falls within this interval. O We are 95% confident that the…arrow_forwardRetinitis pigmentosa (RP) is a hereditary ocular diseasein which patches of pigment appear on the retina, potentially resulting in substantial vision loss and in somecases complete blindness. An important issue is how fastthe subjects decline. Visual field is an important measureof area of vision, which is measured in degree2. A visualfield area for a normal person is around 11,000 degree2.The longitudinal data in Table 11.29 were provided by anindividual patient.Table 11.29 Longitudinal visual field data forone RP patientTime Visual field area lnVisit (yr) (degree2) (visual field area)1 0 3059 8.032 1 3053 8.023 2 1418 7.264 3 1692 7.435 4 1978 7.596 5 1567 7.367 6 1919 7.568 7 1998 7.609 11 1648 7.4110 13 1721 7.4511 15 1264 7.14mean 6.09 1938 7.532sd 4.97 597 0.280Suppose the rate of change of ln (visual field) is a linearfunction of follow-up time.11.103 Write down a linear regression model that summarizes this relationship.arrow_forward
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