The CTR consumer panel previously focused on local clients, while TNS Worldpanel China concentrated on global clients based overseas but with operations in mainland China.
The services have now merged under the TNS Worldpanel brand and will be led by Jason Yu, who has been appointed general manager of TNS Worldpanel China.
Following the merger, TNS Worldpanel China now continuously measures household consumption across a variety of product categories including cosmetics, food and beverages, and the toiletry/household sector.
It has built its services on its national urban panel, a pre-recruited sample of families covering 20 provinces and four cities: Beijing; Tianjin; Shanghai; and Chongquing.
David Lowden, chief executive of TNS, said: "Unifying these two panels under the TNS Worldpanel brand means a bright new future for our clients. China's consumption is growing rapidly and many brands require continuous research to measure their share as buying power grows and as brands build their market position."
Madam Chen Ruoyu, president of CTR Market Research, said: "This is a big event in China's market research industry and will bring significant benefits for clients. TNS Worldpanel has an excellent reputation and it makes sense to develop our continuous research service under the highly regarded brand of TNS Worldpanel."