armd: armd Data (867 x 8)
In nlmeU: Datasets and Utility Functions Enhancing Functionality of 'nlme' Package

armd	R Documentation

armd Data (867 x 8)

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.