Table 3.

Performance of the IPAQ-SF within specific levels of activity: Correlations between objective/fitness measures and physical activity sub-scores at different levels of intensity from 15 studies

Reference	Objective standard	Objective standard unit	IPAQ-SF intensity (min/wk) (ρ)			Re-categorization by the investigators
			Vigorous	Moderate	Walking
Ishikawa-Takata 2008 [28]	Doubly labeled water	TEE				/(3 categories)‡
		PAL				* (3 categories) ‡
Lachat 2008 [35]	accelerometer	Count	0.29	-0.01
Mader 2006 [36]1	accelerometer	Count	-0.18	0.23	0.42b	0.43 (moderate + walking)
Dinger 2006 [25]2	accelerometer	Step	0.30	0.14
Kolbe-Alexander 2006 [43]3	accelerometer	Count		0.37†	0.57†a
				0.08††	0.42††b
Rangul 2008 [23]4	accelerometer	TEE				0.09 (3 categories) ‡
		PAL				0.03 (3 categories) ‡
Kurtze 2008 [34]5	accelerometer	AEE	0.05	0.16
		PAL	0.08	0.14
Mader 2006 [36]1	accelerometer	Vigorous PA min/wk (Swartz)	-0.03
Dinger 2006 [25]2	accelerometer	Vigorous + moderate 10-min bout	0.44b	0.19
		Vigorous PA min/wk	0.47b
Cust 2009 [40]6	accelerometer	Vigorous PA min/wk	0.28#
			0.32##
Timperio 2004 [42]7	accelerometer	Vigorous PA min/wk	0.15¶
			0.28¶¶
Kolbe-Alexander 2006 [43]3	accelerometer	Vigorous count (Freedson)	0.43†b
			0.05††
Ramirez-Marrero 2010 [38]8	accelerometer	Moderate PA min/wk (Freedson)	0.23	-0.03
		Vigorous + moderate min/wk (Freedson)				0.15 (Vigorous + moderate min/wk)
Mader 2006 [36]1	accelerometer	Moderate PA min/wk (Swartz)		0.38	0.27	0.39 (moderate + walking)
Dinger 2006 [25]2	accelerometer	Moderate PA min/wk		0.23
Cust 2009 [40]6	accelerometer	Moderate PA min/wk		0.34#		0.32# (moderate + walking)
				0.01##		0.08## (moderate + walking)
Timperio 2004 [42]7	accelerometer	Moderate PA min/wk		0.13¶
				0.27¶¶
Kolbe-Alexander 2006 [43]3	accelerometer	Moderate PA min/wk		0.31†	0.56†a
				-0.09††	0.08††
Ramirez-Marrero 2010 [38]8	pedometer	Count	0.16	0.76a		0.18 (vigorous + moderate min/wk)
De Cocker 2009 [30]	pedometer	Count	0.20	0.33	0.15
Deng 2008 [20]	pedometer	Count	-0.09	0.05	0.51a
Dinger 2006 [25]2	pedometer	Count	0.38	0.17
Reference	Fitness measure	Fitness measure unit	IPAQ-SF intensity (min/wk) (ρ)			Re-categorization by the investigators
			Vigorous	Moderate	Walking
Papathanasiou 2010 [37]	Treadmill	Maximum time endured	0.43b	0.16
Rangul 2008 [25]4	VO2max	Walking distance				0.32 (3 categories)
Kurtze 2008 [34]5	VO2max	ml/kg/min	0.41b	0.19
Mader 2006 [36]1	VO2max	ml/kg/min			0.29
Fogelholm 2006 [41]	VO2max	ml/kg/min	*‡‡‡			* (5 categories) ‡‡
Egeland 2008 [44]	Body fat	Percentage	-0.26
Fogelholm 2006 [41]	Sit-ups	Maximum number	*‡‡‡			* (5 categories) ‡‡
	Push-up	Maximum number	*‡‡‡			* (5 categories) ‡‡
	Squats	Maximum number	*‡‡‡			* (5 categories) ‡‡

AEE: average energy expenditure

TEE: total energy expenditure;

PAL: physical activity level (TEE/basal metabolic rate)

MET: metabolic equivalent task

MET min/wk (Swartz): moderate PA: 574≤ count/min ≤4945, vigorous PA: count/min > 4945

MET min/wk (Freedson): moderate PA: 1952≤ count/min ≤5724, vigorous PA: count/min > 5724

Studies cited more than once have been identified with the same superscript number

3 categories‡: novel definition [23] of: low, moderate, high

5 categories‡‡: novel definition [36] of five quintiles according to IPAQ-SF total MET score (‡‡)/time spent on vigorous activity (‡‡‡)

^a: moderate effect size (0.5 - 0.79)

^b: approaching moderate effect size (0.4 - 0.49)

†/††: male/female

#/##: high/low confidence

¶/¶¶: with/without logbook

*: significant (p <0.05) between-category difference from ANOVA test

/: nonsignificant (p >0.05) between-category difference from ANOVA test