brms (version 0.1.0)

inhaler: Clarity of inhaler instructions

Description

Ezzet and Whitehead (1991) analyse data from a two-treatment, two-period crossover trial to compare 2 inhalation devices for delivering the drug salbutamol in 286 asthma patients. Patients were asked to rate the clarity of leaflet instructions accompanying each device, using a 4-point ordinal scale.

Usage

inhaler

source

Ezzet, F., & Whitehead, J. (1991). A random effects model for ordinal responses from a crossover trial. Statistics in Medicine, 10(6), 901-907.

Examples

# ordinal regression with family "sratio"
fit_i1 <- brm(rating ~ treat + period + carry, data = inhaler,
              family = "sratio", prior = prior = list(b = "normal(0,5)"))
brm.plot(fit_i1)
print(fit_i1)

# ordinal regression with family "cumulative" and random intercept over subjects
fit_i2 <- brm(rating ~ treat + period + carry + (1|subject), data = inhaler,
           family = "cumulative", n.iter = 2000, prior = list(b = "normal(0,5)"))
brm.plot(fit_i2)
print(fit_i2)