Reading XLSX file

#install.packages("readxl")
library(readxl)

mydata <- read_xlsx("./Medicine.xlsx")

Calculate the average number of headaces for three groups of therapies.

library(psych)
describeBy(mydata$Headache, group = mydata$Medicine)

## 
##  Descriptive statistics by group 
## group: A
##    vars  n mean    sd median trimmed   mad min max range skew
## X1    1 10 41.5 10.56   39.5      41 11.86  28  59    31  0.3
##    kurtosis   se
## X1    -1.45 3.34
## ---------------------------------------------------- 
## group: B
##    vars  n mean    sd median trimmed  mad min max range  skew
## X1    1 10   37 10.37   40.5   37.75 5.93  18  50    32 -0.66
##    kurtosis   se
## X1     -1.1 3.28
## ---------------------------------------------------- 
## group: C
##    vars  n mean   sd median trimmed   mad min max range skew kurtosis
## X1    1 10 26.8 8.84     24   26.75 11.12  15  39    24 0.14    -1.84
##     se
## X1 2.8