Vitacca et al. (A-51) conducted a study to determine whether the supine position or sitting position worsens static, forced expiratory flows and measurements of lung mechanics. Subjects were aged persons living in a nursing home who were clinically stable and without clinical evidence of cardiorespiratory diseases. Among the data collected were the following FEV1 percent values for subjects in sitting and supine postures:

(a) Perform a statistical analysis of the data (including hypothesis testing and confidence interval construction) that you think would yield useful information for the researchers.

(b) State all assumptions that are necessary to validate your analysis.

(c) Find p values for all computed test statistics

(d) Describe the population(s) about which you think inferences based on your analysis would be applicable.

Sitting Supine Sitting Supine 64 56 103 94 44 37 109 92 44 39 -99 -99 40 43 169 165 32 32 73 66 70 61 95 94 82 58 -99 -99 74 48 73 58 91 63 Source: Data provided courtesy of Dr. M. Vitacca