Always ask yourself if the study targeted individuals with similar presentations to your target population
Individuals with speech, language, communication or swallowing difficulties vary in many ways. They may vary in age, underlying diagnosis, severity of difficulty and how the difficulty was caused (e.g. congenital or acquired).
Some intervention strategies/treatments work differently in people who have speech, language, communication or swallowing difficulties as part of an underlying medical diagnosis since birth, or who have acquired these difficulties through brain injury.
REMEMBER: Ask whether the individual is very different from the people in fair comparisons of treatments.