eNOITasUp YOU SPIRITATZ 712 DISPLAYING DATA of the step enoftenia 3.4 EXCERPT FROM THE RESEARCH ARTICLE1 91032 risibsm ent a oloriveq vnem work Box and Whisker Plot We enrolled 99 depressed patients [in Korea]. The baseline clinical evaluation was completed in close proximity to the bio- logical studies. Blood was drawn between 0800 and 1000 hours Serotonin Transporter Gene and for genotyping and 5-HT uptake measures. Anti-Depressant Response Eighty-eight of the 99 enrolled patients (88.8 %) completed the 6-week treatment trial. . . Brisa sham Scholl's P = 0.02 noi tenoweaug beherff aston el salle tuo stiw .a STATISTICAL GUIDE brust vilsu SO a The box and whisker plot is a simple way to visualize the spread or 6 - BismA To review dispersion of a set of scores. Three box and whisker plots can be seen median and below in Figure 1. You will notice that there are three rectangles. This interquartile Vmax (pmole/10 platelets/min) is the box. The whiskers are the lines that extend out from the top and range, see Exercise 2.3. id Juode Ameli bottom of the three rectangles. Here's a guide for interpreting a box and isdanw whisker plot: 59101 AL YEW 2 yborte aint ST. Median Seslamsa 69102 Line in the rectangle 75th percentile Top of the rectangle STOM 25th percentile M/ group (n=22) s/ group (n=22) s/s group (n=44) Bottom of the rectangle 5-HTTLPR in Depressive Patients Highest score Top whisker Fig. 1 Box and whisker plot comparison of serotonin uptake rates Lowest score es-E85 (Vmax values, pmoles/10 platelets/minute) among the different var- Bottom whisker iants of 5-HTT gene promoter polymorphism in depressed patients. Each box displays the median, 75th percentile, and 25th percentile values; horizontal bars indicate the highest and lowest observed values BACKGROUND NOTE Serotonin is an important chemical in the brain. (It's a neurotransmitter to be technical about it.) It helps communicate signals between brain cells. For depressed individuals, serotonin is not as efficient in communicat- STUDY QUESTIONS ing signals between brain cells. The study below investigates serotonin genes and the uptake of serotonin in the blood when individuals are Factual Questions given a drug that boosts serotonin levels. 1. How many individuals are in 4. Which group has the widest Figure 1 has three groups: I/1, I/s, and s/s. The / stands for long, each group? whiskers for Vmax scores? and the s stands for short. Each group of the three groups has a dif- 2. What is the median Vmax rate What is that spread? ferent version of a serotonin related gene. The x-axis in Figure 1 is for each group? 5. What are the 75th percen- in the blood. the three groups. The y-axis (Vmax) is the rate of serotonin uptake 3. Which box has the smallest tile Vmax scores for the three spread in Vmax rates? What is groups? that spread? 62 63
