Colorimetric caries activity test was developed by?
LACTOBACILLUS COLONY COUNT TEST 
This caries activity test was introduced by Hadley in 1933. 
COLORIMETRIC SNYDER TEST 
Snyder devised this Colorimetric caries activity test in 1951.
THE SWAB TEST 
Grainger et al developed this test in 1965. It has an advantage over other tests in that no collection of saliva is necessary. So it is valuable in evaluating caries activity in very young children. 
ORA TEST 
This test was developed by Rosenberg et al in 1989 for estimating oral microbial levels.
Essentials of preventive and community dentistry 
Soben Peter 
5th edition
Snyder
Hadley
Grainger
Rosenberg