Accuracy of physical activity assessment during pregnancy: an observational study

Table 3 Single-modality predictors of moderate-vigorous physical activity

Model		True		False			P-
Modality	Cut-off	Positive	Negative	Positive	Negative	Φ	value
PAR	119	13	13	26	0	0.333	0.124
PAR	105	13	12	27	0	0.316	0.158
PAR	112	13	12	27	0	0.316	0.158
SWA	448	10	24	15	3	0.333	0.124
SWA	294	13	12	27	0	0.316	0.158
SWA	301	13	12	27	0	0.316	0.158

Model shows the modality (PAR = physical activity record, SWA = SenseWear^® armband) and the cut-off, in minutes per week of recorded moderate-to-vigorous physical activity. True/false/positive/negative data shows the number of participants in each category (out of a total of 52 participants) compared to the reference standard. Φ is the 2 × 2 contingency correlation coefficient. Significance was set at P < 0.05.

ISSN: 1471-2393