Just days after the holidays, Statistics Canada wants to the measure the waistlines of hundreds of Ottawa residents for a national health survey. 

Statistics Canada is choosing 500 households in the nation's capital for the Canadian Health Measures Survey (CHMS), an ongoing cross-country survey to assess the health of Canadians.

The survey begins Jan. 3 and includes two phases: an in-home interview with the chosen participant and a physical exam at a mobile clinic in Ottawa at a later date. 

Statistics Canada interviewers will first ask participants about their nutrition, alcohol consumption, medical history and level of physical activity. 

The second phase of the survey will take place inside trailers in a parking lot near the Health Canada facility at Tunney's Pasture, where health measure specialists will take blood and urine samples and measure participants' height, weight, blood pressure and waistlines. 

Approximately 28,500 Canadians participated

Janine Clarke, a unit head with the CHMS, said the survey is done in cycles every two years. The first cycle started in 2007 and Ottawa is participating in the sixth cycle. Approximately 28,500 Canadians aged three to 79 have participated in the survey since its inception, according to Clarke. 

The CHMS gives Canada's statistics agency a more comprehensive and more accurate look into the health of Canadians, she said.

"The direct physical measures give us, in some cases, a more accurate picture of the health of Canadians compared to some of the other health data that's typically based on self-report measures," Clarke said.

"One thing that we've been able to do also is to make a comparison between the answers that people give to certain self-report questions, compared to some of the direct measurements that we take."

The in-house interview will take about one  hour to complete, while the follow-up examination will last around two hours. Each phase of the survey is voluntary and the information provided to Statistics Canada is kept confidential under provisions of the Statistics Act. 

Health Canada and the Public Health Agency of Canada are partnering with Statistics Canada to provide input on the survey's content.