5. A study was performed to compare the e↵ect of dietarysupplementation with a low-ï¬bre reï¬ned wheat product on the serumcholesterol of 20 healthy participants aged 23-49 years. Eachsubject had a cholesterol level measured at baseline and then wasrandomly assigned to receive either a high-ï¬bre or lowï¬bre diet for6 weeks. A 2-week period followed during which no supplements weretaken. Participants then took the alternative supplement for a6-week period. The results are shown below:
n   Baseline   High fiber low fiberdifference(high fibre - low fibre) difference(high fibre -baseline)   difference(low fibre-baseline)
total Cholesterol(mg/dl) Â Â 20 186 +-31 Â Â 172+-28 172+-25 -1 Â Â -14 Â Â -13
(-8, +7) (-21,7) Â Â (-20,7)
(a) Does the high-ï¬bre diet change cholesterol level from baseline?Justify your answer.
(b)Does the low-ï¬bre diet change cholesterol level from baseline?Justify your answer.
(c)Is the change due to the high-ï¬bre diet di↵erent from the changedue to the low-ï¬bre diet? Justify.
