Table 3 Comparison of the size of convex hulls (CH) derived from questionnaire and CH derived from GPS (n = 23) and prompted recall data (n = 31) collected in Montreal, Canada in 2011

Questionnaire and GPS (n = 23)

Questionnaire activity locations

2. 6 (1.0, 6.3)

N.A

GPS tracks

27.8 (11.7, 186.9)

4.1 (1.2, 41. 5)

GPS activity locations

5.9 (2.1, 58.7)

27.7 (1.9, 74.0)

Questionnaire and prompted recall survey (n = 31)

Questionnaire activity locations

2.6 (1.0, 6.7)

N.A

Prompted recall activity locations

15.5 (6.0, 69.2)

10.8 (3.4, 61.1)