I don't think it matters in the context of analyzing the effects of these open carry laws unless you could show that there was another variable confounding the results.
Interesting stat, got a source I could read?
I’ll let you find the individual research paper that you find determine to be most complete. Here is a list.
Studies Exploring the Effects of Shall-Issue Concealed-Carry Laws on Violent Crime, 1997–2004
Study Significant Effect Reported (Main Specification)
Lott and Mustard (1997)a Decrease in violent crime, murders, rapes, and assaults
Bartley and Cohen (1998) Decrease in violent crime robust to alternate model specifications
Black and Nagin (1998) Increase in assaults
Bronars and Lott (1998) Decrease in murders and rapes, displacement of crime to other jurisdictions
Lott (1998a)a Decrease in violent crime in most states implementing the law
Lott (1998b)a Decrease in violent crime; increase in property crime
Ludwig (1998) None detected
Ayres and Donohue (1999)a Increase in property crime
Lott and Landes (1999)a Decrease in murders and injuries from multiple-victim public shootings
Lott (2000)a Decrease in all crime categories
Benson and Mast (2001) Decrease in violent crime, murders, rapes, and robberies
Duggan (2001) Decrease in assaults
Moody (2001)a Decrease in violent crime
Olson and Maltz (2001) Decrease in firearm murders
Plassmann and Tideman (2001) Decrease in murders and rapes; increase in robberies
Lott and Whitley (2003)a Decrease in violent crime, murders, rapes, and robberies
Plassmann and Whitley (2003)b Decrease in rapes and robberies
Rubin and Dezhbakhsh (2003) Decrease in murders; increase in robberies
Ayres and Donohue (2003a)a Increase in more crime categories than saw a decrease
Ayres and Donohue (2003b)a Increase or no effect in all crime categories
Donohue (2003)a Mixed; effects were sensitive to model specifications and data
Helland and Tabarrok (2004) Increase in property crime, auto thefts, and larcenies