Dear Hovsep Ghazaryan,

There is NO difference; they refer to the same term:

 The Cochran–Armitage test for trend, named for William Cochran and Peter Armitage, is used in categorical data analysis when the aim is to assess for the presence of an association between a variable with two categories and a variable with k categories. It modifies the Pearson chi-squared test to incorporate a suspected ordering in the effects of the k categories of the second variable.

For the calculations, please use the following links:

https://help.xlstat.com/customer/en/portal/articles/2062256

http://www.protocol-online.org/biology-forums/posts/35072.html

See answers depicted in the above link.

http://www.jmp.com/support/help/Cochran_Armitage_Trend_Test.shtml

https://stat.ethz.ch/pipermail/r-help/2005-November/083554.html

http://www.gwaspi.org/?page_id=333

http://www.ajmsewing.co.uk/se/cochran-armitage-trend-test-online-calculator.html

Hoping this will be helpful,

Rafik