randomized using the drawing of lots and concealed
from the investigator who took the outcome measurements.
Following the application, outcome measures
were again taken. Participant blinding was facilitated by
recruitment of people who had no experience of the
manipulative therapy techniques applied to the shoulder
and by careful instruction that did not refer to the
study’s aims of evaluation of a treatment technique.
Subjects were informed that the study was investigating
the effects of manual handling on shoulder pain. An exit
questionnaire assessed the adequacy of patient blinding.
Results of the exit questionnaire showed that three
participants (12%) correctly guessed they had only
received active treatment and none had correctly
guessed that they had received either a sham or control.