Physical Activity in Vietnam: Estimates and Measurement Issues.
BACKGROUND
Our aims were to provide the first national estimates of physical activity (PA) for Vietnam, and to investigate issues affecting their accuracy.


METHODS
Measurements were made using the Global Physical Activity Questionnaire (GPAQ) on a nationally-representative sample of 14706 participants (46.5% males, response 64.1%) aged 25-64 years selected by multi-stage stratified cluster sampling.


RESULTS
Approximately 20% of Vietnamese people had no measureable PA during a typical week, but 72.9% (men) and 69.1% (women) met WHO recommendations for PA by adults for their age. On average, 52.0 (men) and 28.0 (women) Metabolic Equivalent Task (MET)-hours/week (largely from work activities) were reported. Work and total PA were higher in rural areas and varied by season. Less than 2% of respondents provided incomplete information, but an additional one-in-six provided unrealistically high values of PA. Those responsible for reporting errors included persons from rural areas and all those with unstable work patterns. Box-Cox transformation (with an appropriate constant added) was the most successful method of reducing the influence of large values, but energy-scaled values were most strongly associated with pathophysiological outcomes.


CONCLUSIONS
Around seven-in-ten Vietnamese people aged 25-64 years met WHO recommendations for total PA, which was mainly from work activities and higher in rural areas. Nearly all respondents were able to report their activity using the GPAQ, but with some exaggerated values and seasonal variation in reporting. Data transformation provided plausible summary values, but energy-scaling fared best in association analyses.
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia; Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam.
Tan Van
TV
Bui
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Christopher Leigh
CL
Blizzard
Medical Services Administration, Ministry of Health of the Socialist Republic of Vietnam, Ha Noi, Vietnam.
Khue Ngoc
KN
Luong
Medical Services Administration, Ministry of Health of the Socialist Republic of Vietnam, Ha Noi, Vietnam.
Ngoc Le Van
Nle V
Truong
Medical Services Administration, Ministry of Health of the Socialist Republic of Vietnam, Ha Noi, Vietnam.
Bao Quoc
BQ
Tran
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Petr
P
Otahal
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia; Department of Medicine, Southern Clinical School, Monash Medical Centre, Monash University, Melbourne, Victoria, Australia.
Velandai
V
Srikanth
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Mark Raymond
MR
Nelson
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Thuy Bich
TB
Au
Medical Services Administration, Ministry of Health of the Socialist Republic of Vietnam, Ha Noi, Vietnam.
Son Thai
ST
Ha
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Hai Ngoc
HN
Phung
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Mai Hoang
MH
Tran
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia; Department of Medicine, Southern Clinical School, Monash Medical Centre, Monash University, Melbourne, Victoria, Australia.
Michele
M
Callisaya
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.
Seana
S
Gall
D000328:Adult; D005260:Female; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D011795:Surveys and Questionnaires; D014744:Vietnam