[R] Missing values detected when there are no missing values

[Bob Green]

I am hoping for some advice on the following matters.

I have a csv data file with 153 variables x 92 rows.   To determine what 
the variables looked like I ran the summary command.  One variable had a 
large number of missing values  54/92.  For some reason, all subsequent 74 
variables are reported as having 92 NA values, irrespective of whether the 
original csv variable was complete or not.

Below are the commands I ran:

 > study1dat <- read.csv("c:\\study1r.csv",header=T)
 > attach(study1dat)
 > names(study1dat)
 > summary(study1dat)

The second puzzling issue, is that one variable with no missing values is 
reported in R as having 3 missing values, whereas there are no missing 
values in the csv file.
The only errors in reading the data I received were:

   	The following object(s) are masked from package:stats :
          time

         The following object(s) are masked from package:graphics :
          screen

         The following object(s) are masked from package:datasets :
          sleep

         The following object(s) are masked from package:base :
	pipe

I am happy to send the csv file if required. Any advice that can offered is 
appreciated,

Bob