We recruited 228 individuals with chronic nonspecific neck pain from an integrated health care system and the general population , and randomized them to 5 groups receiving various doses of massage ( a 4-week course consisting of 30-minute visits 2 or 3 times weekly or 60-minute visits 1 , 2 , or 3 times weekly ) or to a single control group ( a 4-week period on a wait list ) .