armd: armd Data (867 x 8)

In nlmeU: Datasets and utility functions enhancing functionality of nlme package.

Description

Data from Age-Related Macular Degeneration (ARMD) clinical trial

Format

The armd data frame has 867 rows and 8 columns. It contains data for n=234 subjects stored in a long format with up to four rows for one subject.

subject

a factor with 234 levels 1, 2, 3, 4, 6, ..., 240

treat.f

a factor with 2 levels Placebo, Active

visual0

an integer vector with values ranging from 20 to 85

miss.pat

a factor with 8 levels ----, ---X, --X-, --XX, -XX-, ..., X-XX

time.f

a factor with 4 levels 4wks, 12wks, 24wks, 52wks

time

a numeric vector with values 4, 12, 24, 52

visual

an integer vector with values ranging from 3 to 85

tp

a numeric vector with values 1, 2, 3, 4 corresponding to time points 4, 12, 24, 52, respectively

Details

The ARMD data arise from a randomized multi-center clinical trial comparing an experimental treatment (interferon-alpha) versus placebo for patients diagnosed with ARMD.

Source

Pharmacological Therapy for Macular Degeneration Study Group (1997). Interferon alpha-IIA is ineffective for patients with choroidal neovascularization secondary to age-related macular degeneration. Results of a prospective randomized placebo-controlled clinical trial. Archives of Ophthalmology, 115, 865-872.

See Also

armd0, armd.wide

Examples

summary(armd)

Example output

Attaching package: 'nlmeU'

The following object is masked from 'package:stats':

    sigma

    subject       treat.f       visual0        miss.pat     time.f   
 2      :  4   Placebo:451   Min.   :20.0   ----   :752   4wks :231  
 4      :  4   Active :416   1st Qu.:45.0   ---X   : 72   12wks:227  
 6      :  4                 Median :56.0   --XX   : 16   24wks:214  
 7      :  4                 Mean   :54.9   --X-   : 12   52wks:195  
 8      :  4                 3rd Qu.:66.0   -XXX   :  6              
 9      :  4                 Max.   :85.0   X---   :  6              
 (Other):843                                (Other):  3              
      time           visual            tp      
 Min.   : 4.00   Min.   : 3.00   Min.   :1.00  
 1st Qu.: 4.00   1st Qu.:36.00   1st Qu.:1.00  
 Median :12.00   Median :50.00   Median :2.00  
 Mean   :21.83   Mean   :48.45   Mean   :2.43  
 3rd Qu.:24.00   3rd Qu.:62.00   3rd Qu.:3.00  
 Max.   :52.00   Max.   :85.00   Max.   :4.00  
                                               

nlmeU documentation built on May 2, 2019, 6:50 p.m.