The overall adequate medical approach rate in emergency cases was very low (3.9 of 10 cases) in pre-test evaluation.
In any case, both groups already had good knowledge about the illness, according to pre-test evaluation.
Data from the pre-test evaluation were not included in the final analysis.
Before any instruction was given, all 27 physicians completed a pre-test evaluation for both applications (pulmonary edema and pneumothorax).
Of the total Berlin sample, 519 persons (26.0%) had initially been contacted for preceding pre-test evaluation, leaving a total of n = 1481 persons for the main study.
It consisted of a pre-test evaluation of the students' prior knowledge and understanding of two topics followed by a tutorial on each topic.
We confirmed content validity at the pre-test evaluation in that the original questionnaire items were relevant for young active individuals undergoing ACLR in Poland.
Subsequently MSUS was performed by one sono-rheumatologist (HR) and the results, given descriptively as morphological and vascularization data of the studied joints were presented for post-test assessment to the same rheumatologist who had performed the pre-test evaluation.
A pre-test evaluation included measurement of height (cm) and body mass (kg) using a stadiometer (Seca 206, Seca, Hamburg, Germany) and a scale (Beurer PS-16, Beurer, Ulm, Germany), respectively.
For preceding pre-test evaluation, a random sample of n = 100 stratified by sex and five age groups (65-69, 75-79, 75-79, 85+84, 85+ years) was drawn from the German Telephone Health Survey sample 2007 [ 25].
Anticipating an overall response rate of about 20% and an overall proportion of unverifiable contacts of 5-10%, the total sample size was sufficiently large to achieve a study population of n = 300 for the main study and of n = 100 for preceding pre-test evaluation.
