Punctuation marks in parentheses

[herbivorie]

Last year we conducted an international survey on XXX (survey ID, ABC2013; participating countries, Japan, the United States, and Belgium; sample size, 12,570 students in total; survey period, April 2013 to November 2013).

I know a semicolon is stronger than a comma, so I used semicolons to divide the items and I used commas after the item name and the contents of the item (in the parentheses). However, there are 3 participating countries and I used commas between the countries too, which I guess is not a correct usage of punctuations. In the above sentence, how should I use punctuation marks?

 

[Rover_KE]

You solution seems satisfactory to me.

 

[Barb_D]

Try changing the commas to colons.

(survey ID: ABC2013; participating countries: Japan, the USA, Belgium; sample size: 12,570 students; survey period: April–November 2013)

 

[MikeNewYork]

I also prefer Barb's use of colons.

 

[herbivorie]

Thank you everyone. Just to make sure one more thing.

How about this?
(survey ID; ABC2013: participating countries; Japan, the USA, Belgium: sample size; 12,570 students: survey period; April–November 2013)
I found a dictionary that says the strongness order of punctuation marks are like this: period > colon > semicolon > comma.
I thought the above might work too according to this rule, but I don't know.

 

[Barb_D]

Absolutely not. A semi-colon separates items. You need something that connects things.